FFmpeg/libavformat/mov.c

/*
 * MOV demuxer
 * Copyright (c) 2001 Fabrice Bellard
 * Copyright (c) 2009 Baptiste Coudurier <baptiste dot coudurier at gmail dot com>
 *
 * first version by Francois Revol <revol@free.fr>
 * seek function by Gael Chardon <gael.dev@4now.net>
 *
 * This file is part of FFmpeg.
 *
 * FFmpeg is free software; you can redistribute it and/or
 * modify it under the terms of the GNU Lesser General Public
 * License as published by the Free Software Foundation; either
 * version 2.1 of the License, or (at your option) any later version.
 *
 * FFmpeg is distributed in the hope that it will be useful,
 * but WITHOUT ANY WARRANTY; without even the implied warranty of
 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
 * Lesser General Public License for more details.
 *
 * You should have received a copy of the GNU Lesser General Public
 * License along with FFmpeg; if not, write to the Free Software
 * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA
 */

#include <inttypes.h>
#include <limits.h>
#include <stdint.h>

#include "libavutil/attributes.h"
#include "libavutil/channel_layout.h"
#include "libavutil/internal.h"
#include "libavutil/intreadwrite.h"
#include "libavutil/intfloat.h"
#include "libavutil/mathematics.h"
#include "libavutil/time_internal.h"
#include "libavutil/avassert.h"
#include "libavutil/avstring.h"
#include "libavutil/dict.h"
#include "libavutil/display.h"
#include "libavutil/opt.h"
#include "libavutil/aes.h"
#include "libavutil/aes_ctr.h"
#include "libavutil/pixdesc.h"
#include "libavutil/sha.h"
#include "libavutil/spherical.h"
#include "libavutil/stereo3d.h"
#include "libavutil/timecode.h"
#include "libavcodec/ac3tab.h"
#include "libavcodec/flac.h"
#include "libavcodec/mpegaudiodecheader.h"
#include "avformat.h"
#include "internal.h"
#include "avio_internal.h"
#include "riff.h"
#include "isom.h"
#include "libavcodec/get_bits.h"
#include "id3v1.h"
#include "mov_chan.h"
#include "replaygain.h"

#if CONFIG_ZLIB
#include <zlib.h>
#endif

#include "qtpalette.h"

/* those functions parse an atom */
/* links atom IDs to parse functions */
typedef struct MOVParseTableEntry {
    uint32_t type;
    int (*parse)(MOVContext *ctx, AVIOContext *pb, MOVAtom atom);
} MOVParseTableEntry;

static int mov_read_default(MOVContext *c, AVIOContext *pb, MOVAtom atom);
static int mov_read_mfra(MOVContext *c, AVIOContext *f);
static int64_t add_ctts_entry(MOVStts** ctts_data, unsigned int* ctts_count, unsigned int* allocated_size,
                              int count, int duration);

static int mov_metadata_track_or_disc_number(MOVContext *c, AVIOContext *pb,
                                             unsigned len, const char *key)
{
    char buf[16];

    short current, total = 0;
    avio_rb16(pb); // unknown
    current = avio_rb16(pb);
    if (len >= 6)
        total = avio_rb16(pb);
    if (!total)
        snprintf(buf, sizeof(buf), "%d", current);
    else
        snprintf(buf, sizeof(buf), "%d/%d", current, total);
    c->fc->event_flags |= AVFMT_EVENT_FLAG_METADATA_UPDATED;
    av_dict_set(&c->fc->metadata, key, buf, 0);

    return 0;
}

static int mov_metadata_int8_bypass_padding(MOVContext *c, AVIOContext *pb,
                                            unsigned len, const char *key)
{
    /* bypass padding bytes */
    avio_r8(pb);
    avio_r8(pb);
    avio_r8(pb);

    c->fc->event_flags |= AVFMT_EVENT_FLAG_METADATA_UPDATED;
    av_dict_set_int(&c->fc->metadata, key, avio_r8(pb), 0);

    return 0;
}

static int mov_metadata_int8_no_padding(MOVContext *c, AVIOContext *pb,
                                        unsigned len, const char *key)
{
    c->fc->event_flags |= AVFMT_EVENT_FLAG_METADATA_UPDATED;
    av_dict_set_int(&c->fc->metadata, key, avio_r8(pb), 0);

    return 0;
}

static int mov_metadata_gnre(MOVContext *c, AVIOContext *pb,
                             unsigned len, const char *key)
{
    short genre;

    avio_r8(pb); // unknown

    genre = avio_r8(pb);
    if (genre < 1 || genre > ID3v1_GENRE_MAX)
        return 0;
    c->fc->event_flags |= AVFMT_EVENT_FLAG_METADATA_UPDATED;
    av_dict_set(&c->fc->metadata, key, ff_id3v1_genre_str[genre-1], 0);

    return 0;
}

static const uint32_t mac_to_unicode[128] = {
    0x00C4,0x00C5,0x00C7,0x00C9,0x00D1,0x00D6,0x00DC,0x00E1,
    0x00E0,0x00E2,0x00E4,0x00E3,0x00E5,0x00E7,0x00E9,0x00E8,
    0x00EA,0x00EB,0x00ED,0x00EC,0x00EE,0x00EF,0x00F1,0x00F3,
    0x00F2,0x00F4,0x00F6,0x00F5,0x00FA,0x00F9,0x00FB,0x00FC,
    0x2020,0x00B0,0x00A2,0x00A3,0x00A7,0x2022,0x00B6,0x00DF,
    0x00AE,0x00A9,0x2122,0x00B4,0x00A8,0x2260,0x00C6,0x00D8,
    0x221E,0x00B1,0x2264,0x2265,0x00A5,0x00B5,0x2202,0x2211,
    0x220F,0x03C0,0x222B,0x00AA,0x00BA,0x03A9,0x00E6,0x00F8,
    0x00BF,0x00A1,0x00AC,0x221A,0x0192,0x2248,0x2206,0x00AB,
    0x00BB,0x2026,0x00A0,0x00C0,0x00C3,0x00D5,0x0152,0x0153,
    0x2013,0x2014,0x201C,0x201D,0x2018,0x2019,0x00F7,0x25CA,
    0x00FF,0x0178,0x2044,0x20AC,0x2039,0x203A,0xFB01,0xFB02,
    0x2021,0x00B7,0x201A,0x201E,0x2030,0x00C2,0x00CA,0x00C1,
    0x00CB,0x00C8,0x00CD,0x00CE,0x00CF,0x00CC,0x00D3,0x00D4,
    0xF8FF,0x00D2,0x00DA,0x00DB,0x00D9,0x0131,0x02C6,0x02DC,
    0x00AF,0x02D8,0x02D9,0x02DA,0x00B8,0x02DD,0x02DB,0x02C7,
};

static int mov_read_mac_string(MOVContext *c, AVIOContext *pb, int len,
                               char *dst, int dstlen)
{
    char *p = dst;
    char *end = dst+dstlen-1;
    int i;

    for (i = 0; i < len; i++) {
        uint8_t t, c = avio_r8(pb);

        if (p >= end)
            continue;

        if (c < 0x80)
            *p++ = c;
        else if (p < end)
            PUT_UTF8(mac_to_unicode[c-0x80], t, if (p < end) *p++ = t;);
    }
    *p = 0;
    return p - dst;
}

static int mov_read_covr(MOVContext *c, AVIOContext *pb, int type, int len)
{
    AVPacket pkt;
    AVStream *st;
    MOVStreamContext *sc;
    enum AVCodecID id;
    int ret;

    switch (type) {
    case 0xd:  id = AV_CODEC_ID_MJPEG; break;
    case 0xe:  id = AV_CODEC_ID_PNG;   break;
    case 0x1b: id = AV_CODEC_ID_BMP;   break;
    default:
        av_log(c->fc, AV_LOG_WARNING, "Unknown cover type: 0x%x.\n", type);
        avio_skip(pb, len);
        return 0;
    }

    st = avformat_new_stream(c->fc, NULL);
    if (!st)
        return AVERROR(ENOMEM);
    sc = av_mallocz(sizeof(*sc));
    if (!sc)
        return AVERROR(ENOMEM);
    st->priv_data = sc;

    ret = av_get_packet(pb, &pkt, len);
    if (ret < 0)
        return ret;

    if (pkt.size >= 8 && id != AV_CODEC_ID_BMP) {
        if (AV_RB64(pkt.data) == 0x89504e470d0a1a0a) {
            id = AV_CODEC_ID_PNG;
        } else {
            id = AV_CODEC_ID_MJPEG;
        }
    }

    st->disposition              |= AV_DISPOSITION_ATTACHED_PIC;

    st->attached_pic              = pkt;
    st->attached_pic.stream_index = st->index;
    st->attached_pic.flags       |= AV_PKT_FLAG_KEY;

    st->codecpar->codec_type = AVMEDIA_TYPE_VIDEO;
    st->codecpar->codec_id   = id;

    return 0;
}

// 3GPP TS 26.244
static int mov_metadata_loci(MOVContext *c, AVIOContext *pb, unsigned len)
{
    char language[4] = { 0 };
    char buf[200], place[100];
    uint16_t langcode = 0;
    double longitude, latitude, altitude;
    const char *key = "location";

    if (len < 4 + 2 + 1 + 1 + 4 + 4 + 4) {
        av_log(c->fc, AV_LOG_ERROR, "loci too short\n");
        return AVERROR_INVALIDDATA;
    }

    avio_skip(pb, 4); // version+flags
    langcode = avio_rb16(pb);
    ff_mov_lang_to_iso639(langcode, language);
    len -= 6;

    len -= avio_get_str(pb, len, place, sizeof(place));
    if (len < 1) {
        av_log(c->fc, AV_LOG_ERROR, "place name too long\n");
        return AVERROR_INVALIDDATA;
    }
    avio_skip(pb, 1); // role
    len -= 1;

    if (len < 12) {
        av_log(c->fc, AV_LOG_ERROR,
               "loci too short (%u bytes left, need at least %d)\n", len, 12);
        return AVERROR_INVALIDDATA;
    }
    longitude = ((int32_t) avio_rb32(pb)) / (float) (1 << 16);
    latitude  = ((int32_t) avio_rb32(pb)) / (float) (1 << 16);
    altitude  = ((int32_t) avio_rb32(pb)) / (float) (1 << 16);

    // Try to output in the same format as the ?xyz field
    snprintf(buf, sizeof(buf), "%+08.4f%+09.4f",  latitude, longitude);
    if (altitude)
        av_strlcatf(buf, sizeof(buf), "%+f", altitude);
    av_strlcatf(buf, sizeof(buf), "/%s", place);

    if (*language && strcmp(language, "und")) {
        char key2[16];
        snprintf(key2, sizeof(key2), "%s-%s", key, language);
        av_dict_set(&c->fc->metadata, key2, buf, 0);
    }
    c->fc->event_flags |= AVFMT_EVENT_FLAG_METADATA_UPDATED;
    return av_dict_set(&c->fc->metadata, key, buf, 0);
}

static int mov_metadata_hmmt(MOVContext *c, AVIOContext *pb, unsigned len)
{
    int i, n_hmmt;

    if (len < 2)
        return 0;
    if (c->ignore_chapters)
        return 0;

    n_hmmt = avio_rb32(pb);
    for (i = 0; i < n_hmmt && !pb->eof_reached; i++) {
        int moment_time = avio_rb32(pb);
        avpriv_new_chapter(c->fc, i, av_make_q(1, 1000), moment_time, AV_NOPTS_VALUE, NULL);
    }
    return 0;
}

static int mov_read_udta_string(MOVContext *c, AVIOContext *pb, MOVAtom atom)
{
    char tmp_key[5];
    char key2[32], language[4] = {0};
    char *str = NULL;
    const char *key = NULL;
    uint16_t langcode = 0;
    uint32_t data_type = 0, str_size, str_size_alloc;
    int (*parse)(MOVContext*, AVIOContext*, unsigned, const char*) = NULL;
    int raw = 0;
    int num = 0;

    switch (atom.type) {
    case MKTAG( '@','P','R','M'): key = "premiere_version"; raw = 1; break;
    case MKTAG( '@','P','R','Q'): key = "quicktime_version"; raw = 1; break;
    case MKTAG( 'X','M','P','_'):
        if (c->export_xmp) { key = "xmp"; raw = 1; } break;
    case MKTAG( 'a','A','R','T'): key = "album_artist";    break;
    case MKTAG( 'a','k','I','D'): key = "account_type";
        parse = mov_metadata_int8_no_padding; break;
    case MKTAG( 'a','p','I','D'): key = "account_id"; break;
    case MKTAG( 'c','a','t','g'): key = "category"; break;
    case MKTAG( 'c','p','i','l'): key = "compilation";
        parse = mov_metadata_int8_no_padding; break;
    case MKTAG( 'c','p','r','t'): key = "copyright"; break;
    case MKTAG( 'd','e','s','c'): key = "description"; break;
    case MKTAG( 'd','i','s','k'): key = "disc";
        parse = mov_metadata_track_or_disc_number; break;
    case MKTAG( 'e','g','i','d'): key = "episode_uid";
        parse = mov_metadata_int8_no_padding; break;
    case MKTAG( 'F','I','R','M'): key = "firmware"; raw = 1; break;
    case MKTAG( 'g','n','r','e'): key = "genre";
        parse = mov_metadata_gnre; break;
    case MKTAG( 'h','d','v','d'): key = "hd_video";
        parse = mov_metadata_int8_no_padding; break;
    case MKTAG( 'H','M','M','T'):
        return mov_metadata_hmmt(c, pb, atom.size);
    case MKTAG( 'k','e','y','w'): key = "keywords";  break;
    case MKTAG( 'l','d','e','s'): key = "synopsis";  break;
    case MKTAG( 'l','o','c','i'):
        return mov_metadata_loci(c, pb, atom.size);
    case MKTAG( 'm','a','n','u'): key = "make"; break;
    case MKTAG( 'm','o','d','l'): key = "model"; break;
    case MKTAG( 'p','c','s','t'): key = "podcast";
        parse = mov_metadata_int8_no_padding; break;
    case MKTAG( 'p','g','a','p'): key = "gapless_playback";
        parse = mov_metadata_int8_no_padding; break;
    case MKTAG( 'p','u','r','d'): key = "purchase_date"; break;
    case MKTAG( 'r','t','n','g'): key = "rating";
        parse = mov_metadata_int8_no_padding; break;
    case MKTAG( 's','o','a','a'): key = "sort_album_artist"; break;
    case MKTAG( 's','o','a','l'): key = "sort_album";   break;
    case MKTAG( 's','o','a','r'): key = "sort_artist";  break;
    case MKTAG( 's','o','c','o'): key = "sort_composer"; break;
    case MKTAG( 's','o','n','m'): key = "sort_name";    break;
    case MKTAG( 's','o','s','n'): key = "sort_show";    break;
    case MKTAG( 's','t','i','k'): key = "media_type";
        parse = mov_metadata_int8_no_padding; break;
    case MKTAG( 't','r','k','n'): key = "track";
        parse = mov_metadata_track_or_disc_number; break;
    case MKTAG( 't','v','e','n'): key = "episode_id"; break;
    case MKTAG( 't','v','e','s'): key = "episode_sort";
        parse = mov_metadata_int8_bypass_padding; break;
    case MKTAG( 't','v','n','n'): key = "network";   break;
    case MKTAG( 't','v','s','h'): key = "show";      break;
    case MKTAG( 't','v','s','n'): key = "season_number";
        parse = mov_metadata_int8_bypass_padding; break;
    case MKTAG(0xa9,'A','R','T'): key = "artist";    break;
    case MKTAG(0xa9,'P','R','D'): key = "producer";  break;
    case MKTAG(0xa9,'a','l','b'): key = "album";     break;
    case MKTAG(0xa9,'a','u','t'): key = "artist";    break;
    case MKTAG(0xa9,'c','h','p'): key = "chapter";   break;
    case MKTAG(0xa9,'c','m','t'): key = "comment";   break;
    case MKTAG(0xa9,'c','o','m'): key = "composer";  break;
    case MKTAG(0xa9,'c','p','y'): key = "copyright"; break;
    case MKTAG(0xa9,'d','a','y'): key = "date";      break;
    case MKTAG(0xa9,'d','i','r'): key = "director";  break;
    case MKTAG(0xa9,'d','i','s'): key = "disclaimer"; break;
    case MKTAG(0xa9,'e','d','1'): key = "edit_date"; break;
    case MKTAG(0xa9,'e','n','c'): key = "encoder";   break;
    case MKTAG(0xa9,'f','m','t'): key = "original_format"; break;
    case MKTAG(0xa9,'g','e','n'): key = "genre";     break;
    case MKTAG(0xa9,'g','r','p'): key = "grouping";  break;
    case MKTAG(0xa9,'h','s','t'): key = "host_computer"; break;
    case MKTAG(0xa9,'i','n','f'): key = "comment";   break;
    case MKTAG(0xa9,'l','y','r'): key = "lyrics";    break;
    case MKTAG(0xa9,'m','a','k'): key = "make";      break;
    case MKTAG(0xa9,'m','o','d'): key = "model";     break;
    case MKTAG(0xa9,'n','a','m'): key = "title";     break;
    case MKTAG(0xa9,'o','p','e'): key = "original_artist"; break;
    case MKTAG(0xa9,'p','r','d'): key = "producer";  break;
    case MKTAG(0xa9,'p','r','f'): key = "performers"; break;
    case MKTAG(0xa9,'r','e','q'): key = "playback_requirements"; break;
    case MKTAG(0xa9,'s','r','c'): key = "original_source"; break;
    case MKTAG(0xa9,'s','t','3'): key = "subtitle";  break;
    case MKTAG(0xa9,'s','w','r'): key = "encoder";   break;
    case MKTAG(0xa9,'t','o','o'): key = "encoder";   break;
    case MKTAG(0xa9,'t','r','k'): key = "track";     break;
    case MKTAG(0xa9,'u','r','l'): key = "URL";       break;
    case MKTAG(0xa9,'w','r','n'): key = "warning";   break;
    case MKTAG(0xa9,'w','r','t'): key = "composer";  break;
    case MKTAG(0xa9,'x','y','z'): key = "location";  break;
    }
retry:
    if (c->itunes_metadata && atom.size > 8) {
        int data_size = avio_rb32(pb);
        int tag = avio_rl32(pb);
        if (tag == MKTAG('d','a','t','a') && data_size <= atom.size) {
            data_type = avio_rb32(pb); // type
            avio_rb32(pb); // unknown
            str_size = data_size - 16;
            atom.size -= 16;

            if (atom.type == MKTAG('c', 'o', 'v', 'r')) {
                int ret = mov_read_covr(c, pb, data_type, str_size);
                if (ret < 0) {
                    av_log(c->fc, AV_LOG_ERROR, "Error parsing cover art.\n");
                    return ret;
                }
                atom.size -= str_size;
                if (atom.size > 8)
                    goto retry;
                return ret;
            } else if (!key && c->found_hdlr_mdta && c->meta_keys) {
                uint32_t index = AV_RB32(&atom.type);
                if (index < c->meta_keys_count && index > 0) {
                    key = c->meta_keys[index];
                } else {
                    av_log(c->fc, AV_LOG_WARNING,
                           "The index of 'data' is out of range: %"PRId32" < 1 or >= %d.\n",
                           index, c->meta_keys_count);
                }
            }
        } else return 0;
    } else if (atom.size > 4 && key && !c->itunes_metadata && !raw) {
        str_size = avio_rb16(pb); // string length
        if (str_size > atom.size) {
            raw = 1;
            avio_seek(pb, -2, SEEK_CUR);
            av_log(c->fc, AV_LOG_WARNING, "UDTA parsing failed retrying raw\n");
            goto retry;
        }
        langcode = avio_rb16(pb);
        ff_mov_lang_to_iso639(langcode, language);
        atom.size -= 4;
    } else
        str_size = atom.size;

    if (c->export_all && !key) {
        snprintf(tmp_key, 5, "%.4s", (char*)&atom.type);
        key = tmp_key;
    }

    if (!key)
        return 0;
    if (atom.size < 0 || str_size >= INT_MAX/2)
        return AVERROR_INVALIDDATA;

    // Allocates enough space if data_type is a int32 or float32 number, otherwise
    // worst-case requirement for output string in case of utf8 coded input
    num = (data_type >= 21 && data_type <= 23);
    str_size_alloc = (num ? 512 : (raw ? str_size : str_size * 2)) + 1;
    str = av_mallocz(str_size_alloc);
    if (!str)
        return AVERROR(ENOMEM);

    if (parse)
        parse(c, pb, str_size, key);
    else {
        if (!raw && (data_type == 3 || (data_type == 0 && (langcode < 0x400 || langcode == 0x7fff)))) { // MAC Encoded
            mov_read_mac_string(c, pb, str_size, str, str_size_alloc);
        } else if (data_type == 21) { // BE signed integer, variable size
            int val = 0;
            if (str_size == 1)
                val = (int8_t)avio_r8(pb);
            else if (str_size == 2)
                val = (int16_t)avio_rb16(pb);
            else if (str_size == 3)
                val = ((int32_t)(avio_rb24(pb)<<8))>>8;
            else if (str_size == 4)
                val = (int32_t)avio_rb32(pb);
            if (snprintf(str, str_size_alloc, "%d", val) >= str_size_alloc) {
                av_log(c->fc, AV_LOG_ERROR,
                       "Failed to store the number (%d) in string.\n", val);
                av_free(str);
                return AVERROR_INVALIDDATA;
            }
        } else if (data_type == 22) { // BE unsigned integer, variable size
            unsigned int val = 0;
            if (str_size == 1)
                val = avio_r8(pb);
            else if (str_size == 2)
                val = avio_rb16(pb);
            else if (str_size == 3)
                val = avio_rb24(pb);
            else if (str_size == 4)
                val = avio_rb32(pb);
            if (snprintf(str, str_size_alloc, "%u", val) >= str_size_alloc) {
                av_log(c->fc, AV_LOG_ERROR,
                       "Failed to store the number (%u) in string.\n", val);
                av_free(str);
                return AVERROR_INVALIDDATA;
            }
        } else if (data_type == 23 && str_size >= 4) {  // BE float32
            float val = av_int2float(avio_rb32(pb));
            if (snprintf(str, str_size_alloc, "%f", val) >= str_size_alloc) {
                av_log(c->fc, AV_LOG_ERROR,
                       "Failed to store the float32 number (%f) in string.\n", val);
                av_free(str);
                return AVERROR_INVALIDDATA;
            }
        } else {
            int ret = ffio_read_size(pb, str, str_size);
            if (ret < 0) {
                av_free(str);
                return ret;
            }
            str[str_size] = 0;
        }
        c->fc->event_flags |= AVFMT_EVENT_FLAG_METADATA_UPDATED;
        av_dict_set(&c->fc->metadata, key, str, 0);
        if (*language && strcmp(language, "und")) {
            snprintf(key2, sizeof(key2), "%s-%s", key, language);
            av_dict_set(&c->fc->metadata, key2, str, 0);
        }
        if (!strcmp(key, "encoder")) {
            int major, minor, micro;
            if (sscanf(str, "HandBrake %d.%d.%d", &major, &minor, &micro) == 3) {
                c->handbrake_version = 1000000*major + 1000*minor + micro;
            }
        }
    }

    av_freep(&str);
    return 0;
}

static int mov_read_chpl(MOVContext *c, AVIOContext *pb, MOVAtom atom)
{
    int64_t start;
    int i, nb_chapters, str_len, version;
    char str[256+1];
    int ret;

    if (c->ignore_chapters)
        return 0;

    if ((atom.size -= 5) < 0)
        return 0;

    version = avio_r8(pb);
    avio_rb24(pb);
    if (version)
        avio_rb32(pb); // ???
    nb_chapters = avio_r8(pb);

    for (i = 0; i < nb_chapters; i++) {
        if (atom.size < 9)
            return 0;

        start = avio_rb64(pb);
        str_len = avio_r8(pb);

        if ((atom.size -= 9+str_len) < 0)
            return 0;

        ret = ffio_read_size(pb, str, str_len);
        if (ret < 0)
            return ret;
        str[str_len] = 0;
        avpriv_new_chapter(c->fc, i, (AVRational){1,10000000}, start, AV_NOPTS_VALUE, str);
    }
    return 0;
}

#define MIN_DATA_ENTRY_BOX_SIZE 12
static int mov_read_dref(MOVContext *c, AVIOContext *pb, MOVAtom atom)
{
    AVStream *st;
    MOVStreamContext *sc;
    int entries, i, j;

    if (c->fc->nb_streams < 1)
        return 0;
    st = c->fc->streams[c->fc->nb_streams-1];
    sc = st->priv_data;

    avio_rb32(pb); // version + flags
    entries = avio_rb32(pb);
    if (!entries ||
        entries >  (atom.size - 1) / MIN_DATA_ENTRY_BOX_SIZE + 1 ||
        entries >= UINT_MAX / sizeof(*sc->drefs))
        return AVERROR_INVALIDDATA;
    sc->drefs_count = 0;
    av_free(sc->drefs);
    sc->drefs_count = 0;
    sc->drefs = av_mallocz(entries * sizeof(*sc->drefs));
    if (!sc->drefs)
        return AVERROR(ENOMEM);
    sc->drefs_count = entries;

    for (i = 0; i < entries; i++) {
        MOVDref *dref = &sc->drefs[i];
        uint32_t size = avio_rb32(pb);
        int64_t next = avio_tell(pb) + size - 4;

        if (size < 12)
            return AVERROR_INVALIDDATA;

        dref->type = avio_rl32(pb);
        avio_rb32(pb); // version + flags

        if (dref->type == MKTAG('a','l','i','s') && size > 150) {
            /* macintosh alias record */
            uint16_t volume_len, len;
            int16_t type;
            int ret;

            avio_skip(pb, 10);

            volume_len = avio_r8(pb);
            volume_len = FFMIN(volume_len, 27);
            ret = ffio_read_size(pb, dref->volume, 27);
            if (ret < 0)
                return ret;
            dref->volume[volume_len] = 0;
            av_log(c->fc, AV_LOG_DEBUG, "volume %s, len %d\n", dref->volume, volume_len);

            avio_skip(pb, 12);

            len = avio_r8(pb);
            len = FFMIN(len, 63);
            ret = ffio_read_size(pb, dref->filename, 63);
            if (ret < 0)
                return ret;
            dref->filename[len] = 0;
            av_log(c->fc, AV_LOG_DEBUG, "filename %s, len %d\n", dref->filename, len);

            avio_skip(pb, 16);

            /* read next level up_from_alias/down_to_target */
            dref->nlvl_from = avio_rb16(pb);
            dref->nlvl_to   = avio_rb16(pb);
            av_log(c->fc, AV_LOG_DEBUG, "nlvl from %d, nlvl to %d\n",
                   dref->nlvl_from, dref->nlvl_to);

            avio_skip(pb, 16);

            for (type = 0; type != -1 && avio_tell(pb) < next; ) {
                if(avio_feof(pb))
                    return AVERROR_EOF;
                type = avio_rb16(pb);
                len = avio_rb16(pb);
                av_log(c->fc, AV_LOG_DEBUG, "type %d, len %d\n", type, len);
                if (len&1)
                    len += 1;
                if (type == 2) { // absolute path
                    av_free(dref->path);
                    dref->path = av_mallocz(len+1);
                    if (!dref->path)
                        return AVERROR(ENOMEM);

                    ret = ffio_read_size(pb, dref->path, len);
                    if (ret < 0) {
                        av_freep(&dref->path);
                        return ret;
                    }
                    if (len > volume_len && !strncmp(dref->path, dref->volume, volume_len)) {
                        len -= volume_len;
                        memmove(dref->path, dref->path+volume_len, len);
                        dref->path[len] = 0;
                    }
                    // trim string of any ending zeros
                    for (j = len - 1; j >= 0; j--) {
                        if (dref->path[j] == 0)
                            len--;
                        else
                            break;
                    }
                    for (j = 0; j < len; j++)
                        if (dref->path[j] == ':' || dref->path[j] == 0)
                            dref->path[j] = '/';
                    av_log(c->fc, AV_LOG_DEBUG, "path %s\n", dref->path);
                } else if (type == 0) { // directory name
                    av_free(dref->dir);
                    dref->dir = av_malloc(len+1);
                    if (!dref->dir)
                        return AVERROR(ENOMEM);

                    ret = ffio_read_size(pb, dref->dir, len);
                    if (ret < 0) {
                        av_freep(&dref->dir);
                        return ret;
                    }
                    dref->dir[len] = 0;
                    for (j = 0; j < len; j++)
                        if (dref->dir[j] == ':')
                            dref->dir[j] = '/';
                    av_log(c->fc, AV_LOG_DEBUG, "dir %s\n", dref->dir);
                } else
                    avio_skip(pb, len);
            }
        } else {
            av_log(c->fc, AV_LOG_DEBUG, "Unknown dref type 0x%08"PRIx32" size %"PRIu32"\n",
                   dref->type, size);
            entries--;
            i--;
        }
        avio_seek(pb, next, SEEK_SET);
    }
    return 0;
}

static int mov_read_hdlr(MOVContext *c, AVIOContext *pb, MOVAtom atom)
{
    AVStream *st;
    uint32_t type;
    uint32_t ctype;
    int64_t title_size;
    char *title_str;
    int ret;

    avio_r8(pb); /* version */
    avio_rb24(pb); /* flags */

    /* component type */
    ctype = avio_rl32(pb);
    type = avio_rl32(pb); /* component subtype */

    av_log(c->fc, AV_LOG_TRACE, "ctype=%s\n", av_fourcc2str(ctype));
    av_log(c->fc, AV_LOG_TRACE, "stype=%s\n", av_fourcc2str(type));

    if (c->trak_index < 0) {  // meta not inside a trak
        if (type == MKTAG('m','d','t','a')) {
            c->found_hdlr_mdta = 1;
        }
        return 0;
    }

    st = c->fc->streams[c->fc->nb_streams-1];

    if     (type == MKTAG('v','i','d','e'))
        st->codecpar->codec_type = AVMEDIA_TYPE_VIDEO;
    else if (type == MKTAG('s','o','u','n'))
        st->codecpar->codec_type = AVMEDIA_TYPE_AUDIO;
    else if (type == MKTAG('m','1','a',' '))
        st->codecpar->codec_id = AV_CODEC_ID_MP2;
    else if ((type == MKTAG('s','u','b','p')) || (type == MKTAG('c','l','c','p')))
        st->codecpar->codec_type = AVMEDIA_TYPE_SUBTITLE;

    avio_rb32(pb); /* component  manufacture */
    avio_rb32(pb); /* component flags */
    avio_rb32(pb); /* component flags mask */

    title_size = atom.size - 24;
    if (title_size > 0) {
        if (title_size > FFMIN(INT_MAX, SIZE_MAX-1))
            return AVERROR_INVALIDDATA;
        title_str = av_malloc(title_size + 1); /* Add null terminator */
        if (!title_str)
            return AVERROR(ENOMEM);

        ret = ffio_read_size(pb, title_str, title_size);
        if (ret < 0) {
            av_freep(&title_str);
            return ret;
        }
        title_str[title_size] = 0;
        if (title_str[0]) {
            int off = (!c->isom && title_str[0] == title_size - 1);
            av_dict_set(&st->metadata, "handler_name", title_str + off, 0);
        }
        av_freep(&title_str);
    }

    return 0;
}

static int mov_read_esds(MOVContext *c, AVIOContext *pb, MOVAtom atom)
{
    return ff_mov_read_esds(c->fc, pb);
}

static int mov_read_dac3(MOVContext *c, AVIOContext *pb, MOVAtom atom)
{
    AVStream *st;
    enum AVAudioServiceType *ast;
    int ac3info, acmod, lfeon, bsmod;

    if (c->fc->nb_streams < 1)
        return 0;
    st = c->fc->streams[c->fc->nb_streams-1];

    ast = (enum AVAudioServiceType*)av_stream_new_side_data(st, AV_PKT_DATA_AUDIO_SERVICE_TYPE,
                                                            sizeof(*ast));
    if (!ast)
        return AVERROR(ENOMEM);

    ac3info = avio_rb24(pb);
    bsmod = (ac3info >> 14) & 0x7;
    acmod = (ac3info >> 11) & 0x7;
    lfeon = (ac3info >> 10) & 0x1;
    st->codecpar->channels = ((int[]){2,1,2,3,3,4,4,5})[acmod] + lfeon;
    st->codecpar->channel_layout = avpriv_ac3_channel_layout_tab[acmod];
    if (lfeon)
        st->codecpar->channel_layout |= AV_CH_LOW_FREQUENCY;
    *ast = bsmod;
    if (st->codecpar->channels > 1 && bsmod == 0x7)
        *ast = AV_AUDIO_SERVICE_TYPE_KARAOKE;

#if FF_API_LAVF_AVCTX
    FF_DISABLE_DEPRECATION_WARNINGS
    st->codec->audio_service_type = *ast;
    FF_ENABLE_DEPRECATION_WARNINGS
#endif

    return 0;
}

static int mov_read_dec3(MOVContext *c, AVIOContext *pb, MOVAtom atom)
{
    AVStream *st;
    enum AVAudioServiceType *ast;
    int eac3info, acmod, lfeon, bsmod;

    if (c->fc->nb_streams < 1)
        return 0;
    st = c->fc->streams[c->fc->nb_streams-1];

    ast = (enum AVAudioServiceType*)av_stream_new_side_data(st, AV_PKT_DATA_AUDIO_SERVICE_TYPE,
                                                            sizeof(*ast));
    if (!ast)
        return AVERROR(ENOMEM);

    /* No need to parse fields for additional independent substreams and its
     * associated dependent substreams since libavcodec's E-AC-3 decoder
     * does not support them yet. */
    avio_rb16(pb); /* data_rate and num_ind_sub */
    eac3info = avio_rb24(pb);
    bsmod = (eac3info >> 12) & 0x1f;
    acmod = (eac3info >>  9) & 0x7;
    lfeon = (eac3info >>  8) & 0x1;
    st->codecpar->channel_layout = avpriv_ac3_channel_layout_tab[acmod];
    if (lfeon)
        st->codecpar->channel_layout |= AV_CH_LOW_FREQUENCY;
    st->codecpar->channels = av_get_channel_layout_nb_channels(st->codecpar->channel_layout);
    *ast = bsmod;
    if (st->codecpar->channels > 1 && bsmod == 0x7)
        *ast = AV_AUDIO_SERVICE_TYPE_KARAOKE;

#if FF_API_LAVF_AVCTX
    FF_DISABLE_DEPRECATION_WARNINGS
    st->codec->audio_service_type = *ast;
    FF_ENABLE_DEPRECATION_WARNINGS
#endif

    return 0;
}

static int mov_read_ddts(MOVContext *c, AVIOContext *pb, MOVAtom atom)
{
    const uint32_t ddts_size = 20;
    AVStream *st = NULL;
    uint8_t *buf = NULL;
    uint32_t frame_duration_code = 0;
    uint32_t channel_layout_code = 0;
    GetBitContext gb;

    buf = av_malloc(ddts_size + AV_INPUT_BUFFER_PADDING_SIZE);
    if (!buf) {
        return AVERROR(ENOMEM);
    }
    if (avio_read(pb, buf, ddts_size) < ddts_size) {
        av_free(buf);
        return AVERROR_INVALIDDATA;
    }

    init_get_bits(&gb, buf, 8*ddts_size);

    if (c->fc->nb_streams < 1) {
        av_free(buf);
        return 0;
    }
    st = c->fc->streams[c->fc->nb_streams-1];

    st->codecpar->sample_rate = get_bits_long(&gb, 32);
    if (st->codecpar->sample_rate <= 0) {
        av_log(c->fc, AV_LOG_ERROR, "Invalid sample rate %d\n", st->codecpar->sample_rate);
        av_free(buf);
        return AVERROR_INVALIDDATA;
    }
    skip_bits_long(&gb, 32); /* max bitrate */
    st->codecpar->bit_rate = get_bits_long(&gb, 32);
    st->codecpar->bits_per_coded_sample = get_bits(&gb, 8);
    frame_duration_code = get_bits(&gb, 2);
    skip_bits(&gb, 30); /* various fields */
    channel_layout_code = get_bits(&gb, 16);

    st->codecpar->frame_size =
            (frame_duration_code == 0) ? 512 :
            (frame_duration_code == 1) ? 1024 :
            (frame_duration_code == 2) ? 2048 :
            (frame_duration_code == 3) ? 4096 : 0;

    if (channel_layout_code > 0xff) {
        av_log(c->fc, AV_LOG_WARNING, "Unsupported DTS audio channel layout");
    }
    st->codecpar->channel_layout =
            ((channel_layout_code & 0x1) ? AV_CH_FRONT_CENTER : 0) |
            ((channel_layout_code & 0x2) ? AV_CH_FRONT_LEFT : 0) |
            ((channel_layout_code & 0x2) ? AV_CH_FRONT_RIGHT : 0) |
            ((channel_layout_code & 0x4) ? AV_CH_SIDE_LEFT : 0) |
            ((channel_layout_code & 0x4) ? AV_CH_SIDE_RIGHT : 0) |
            ((channel_layout_code & 0x8) ? AV_CH_LOW_FREQUENCY : 0);

    st->codecpar->channels = av_get_channel_layout_nb_channels(st->codecpar->channel_layout);
    av_free(buf);

    return 0;
}

static int mov_read_chan(MOVContext *c, AVIOContext *pb, MOVAtom atom)
{
    AVStream *st;

    if (c->fc->nb_streams < 1)
        return 0;
    st = c->fc->streams[c->fc->nb_streams-1];

    if (atom.size < 16)
        return 0;

    /* skip version and flags */
    avio_skip(pb, 4);

    ff_mov_read_chan(c->fc, pb, st, atom.size - 4);

    return 0;
}

static int mov_read_wfex(MOVContext *c, AVIOContext *pb, MOVAtom atom)
{
    AVStream *st;
    int ret;

    if (c->fc->nb_streams < 1)
        return 0;
    st = c->fc->streams[c->fc->nb_streams-1];

    if ((ret = ff_get_wav_header(c->fc, pb, st->codecpar, atom.size, 0)) < 0)
        av_log(c->fc, AV_LOG_WARNING, "get_wav_header failed\n");

    return ret;
}

static int mov_read_pasp(MOVContext *c, AVIOContext *pb, MOVAtom atom)
{
    const int num = avio_rb32(pb);
    const int den = avio_rb32(pb);
    AVStream *st;

    if (c->fc->nb_streams < 1)
        return 0;
    st = c->fc->streams[c->fc->nb_streams-1];

    if ((st->sample_aspect_ratio.den != 1 || st->sample_aspect_ratio.num) && // default
        (den != st->sample_aspect_ratio.den || num != st->sample_aspect_ratio.num)) {
        av_log(c->fc, AV_LOG_WARNING,
               "sample aspect ratio already set to %d:%d, ignoring 'pasp' atom (%d:%d)\n",
               st->sample_aspect_ratio.num, st->sample_aspect_ratio.den,
               num, den);
    } else if (den != 0) {
        av_reduce(&st->sample_aspect_ratio.num, &st->sample_aspect_ratio.den,
                  num, den, 32767);
    }
    return 0;
}

/* this atom contains actual media data */
static int mov_read_mdat(MOVContext *c, AVIOContext *pb, MOVAtom atom)
{
    if (atom.size == 0) /* wrong one (MP4) */
        return 0;
    c->found_mdat=1;
    return 0; /* now go for moov */
}

#define DRM_BLOB_SIZE 56

static int mov_read_adrm(MOVContext *c, AVIOContext *pb, MOVAtom atom)
{
    uint8_t intermediate_key[20];
    uint8_t intermediate_iv[20];
    uint8_t input[64];
    uint8_t output[64];
    uint8_t file_checksum[20];
    uint8_t calculated_checksum[20];
    struct AVSHA *sha;
    int i;
    int ret = 0;
    uint8_t *activation_bytes = c->activation_bytes;
    uint8_t *fixed_key = c->audible_fixed_key;

    c->aax_mode = 1;

    sha = av_sha_alloc();
    if (!sha)
        return AVERROR(ENOMEM);
    c->aes_decrypt = av_aes_alloc();
    if (!c->aes_decrypt) {
        ret = AVERROR(ENOMEM);
        goto fail;
    }

    /* drm blob processing */
    avio_read(pb, output, 8); // go to offset 8, absolute position 0x251
    avio_read(pb, input, DRM_BLOB_SIZE);
    avio_read(pb, output, 4); // go to offset 4, absolute position 0x28d
    avio_read(pb, file_checksum, 20);

    av_log(c->fc, AV_LOG_INFO, "[aax] file checksum == "); // required by external tools
    for (i = 0; i < 20; i++)
        av_log(c->fc, AV_LOG_INFO, "%02x", file_checksum[i]);
    av_log(c->fc, AV_LOG_INFO, "\n");

    /* verify activation data */
    if (!activation_bytes) {
        av_log(c->fc, AV_LOG_WARNING, "[aax] activation_bytes option is missing!\n");
        ret = 0;  /* allow ffprobe to continue working on .aax files */
        goto fail;
    }
    if (c->activation_bytes_size != 4) {
        av_log(c->fc, AV_LOG_FATAL, "[aax] activation_bytes value needs to be 4 bytes!\n");
        ret = AVERROR(EINVAL);
        goto fail;
    }

    /* verify fixed key */
    if (c->audible_fixed_key_size != 16) {
        av_log(c->fc, AV_LOG_FATAL, "[aax] audible_fixed_key value needs to be 16 bytes!\n");
        ret = AVERROR(EINVAL);
        goto fail;
    }

    /* AAX (and AAX+) key derivation */
    av_sha_init(sha, 160);
    av_sha_update(sha, fixed_key, 16);
    av_sha_update(sha, activation_bytes, 4);
    av_sha_final(sha, intermediate_key);
    av_sha_init(sha, 160);
    av_sha_update(sha, fixed_key, 16);
    av_sha_update(sha, intermediate_key, 20);
    av_sha_update(sha, activation_bytes, 4);
    av_sha_final(sha, intermediate_iv);
    av_sha_init(sha, 160);
    av_sha_update(sha, intermediate_key, 16);
    av_sha_update(sha, intermediate_iv, 16);
    av_sha_final(sha, calculated_checksum);
    if (memcmp(calculated_checksum, file_checksum, 20)) { // critical error
        av_log(c->fc, AV_LOG_ERROR, "[aax] mismatch in checksums!\n");
        ret = AVERROR_INVALIDDATA;
        goto fail;
    }
    av_aes_init(c->aes_decrypt, intermediate_key, 128, 1);
    av_aes_crypt(c->aes_decrypt, output, input, DRM_BLOB_SIZE >> 4, intermediate_iv, 1);
    for (i = 0; i < 4; i++) {
        // file data (in output) is stored in big-endian mode
        if (activation_bytes[i] != output[3 - i]) { // critical error
            av_log(c->fc, AV_LOG_ERROR, "[aax] error in drm blob decryption!\n");
            ret = AVERROR_INVALIDDATA;
            goto fail;
        }
    }
    memcpy(c->file_key, output + 8, 16);
    memcpy(input, output + 26, 16);
    av_sha_init(sha, 160);
    av_sha_update(sha, input, 16);
    av_sha_update(sha, c->file_key, 16);
    av_sha_update(sha, fixed_key, 16);
    av_sha_final(sha, c->file_iv);

fail:
    av_free(sha);

    return ret;
}

// Audible AAX (and AAX+) bytestream decryption
static int aax_filter(uint8_t *input, int size, MOVContext *c)
{
    int blocks = 0;
    unsigned char iv[16];

    memcpy(iv, c->file_iv, 16); // iv is overwritten
    blocks = size >> 4; // trailing bytes are not encrypted!
    av_aes_init(c->aes_decrypt, c->file_key, 128, 1);
    av_aes_crypt(c->aes_decrypt, input, input, blocks, iv, 1);

    return 0;
}

/* read major brand, minor version and compatible brands and store them as metadata */
static int mov_read_ftyp(MOVContext *c, AVIOContext *pb, MOVAtom atom)
{
    uint32_t minor_ver;
    int comp_brand_size;
    char* comp_brands_str;
    uint8_t type[5] = {0};
    int ret = ffio_read_size(pb, type, 4);
    if (ret < 0)
        return ret;

    if (strcmp(type, "qt  "))
        c->isom = 1;
    av_log(c->fc, AV_LOG_DEBUG, "ISO: File Type Major Brand: %.4s\n",(char *)&type);
    av_dict_set(&c->fc->metadata, "major_brand", type, 0);
    minor_ver = avio_rb32(pb); /* minor version */
    av_dict_set_int(&c->fc->metadata, "minor_version", minor_ver, 0);

    comp_brand_size = atom.size - 8;
    if (comp_brand_size < 0)
        return AVERROR_INVALIDDATA;
    comp_brands_str = av_malloc(comp_brand_size + 1); /* Add null terminator */
    if (!comp_brands_str)
        return AVERROR(ENOMEM);

    ret = ffio_read_size(pb, comp_brands_str, comp_brand_size);
    if (ret < 0) {
        av_freep(&comp_brands_str);
        return ret;
    }
    comp_brands_str[comp_brand_size] = 0;
    av_dict_set(&c->fc->metadata, "compatible_brands", comp_brands_str, 0);
    av_freep(&comp_brands_str);

    return 0;
}

/* this atom should contain all header atoms */
static int mov_read_moov(MOVContext *c, AVIOContext *pb, MOVAtom atom)
{
    int ret;

    if (c->found_moov) {
        av_log(c->fc, AV_LOG_WARNING, "Found duplicated MOOV Atom. Skipped it\n");
        avio_skip(pb, atom.size);
        return 0;
    }

    if ((ret = mov_read_default(c, pb, atom)) < 0)
        return ret;
    /* we parsed the 'moov' atom, we can terminate the parsing as soon as we find the 'mdat' */
    /* so we don't parse the whole file if over a network */
    c->found_moov=1;
    return 0; /* now go for mdat */
}

static MOVFragmentStreamInfo * get_frag_stream_info(
    MOVFragmentIndex *frag_index,
    int index,
    int id)
{
    int i;
    MOVFragmentIndexItem * item;

    if (index < 0 || index >= frag_index->nb_items)
        return NULL;
    item = &frag_index->item[index];
    for (i = 0; i < item->nb_stream_info; i++)
        if (item->stream_info[i].id == id)
            return &item->stream_info[i];

    // This shouldn't happen
    return NULL;
}

static void set_frag_stream(MOVFragmentIndex *frag_index, int id)
{
    int i;
    MOVFragmentIndexItem * item;

    if (frag_index->current < 0 ||
        frag_index->current >= frag_index->nb_items)
        return;

    item = &frag_index->item[frag_index->current];
    for (i = 0; i < item->nb_stream_info; i++)
        if (item->stream_info[i].id == id) {
            item->current = i;
            return;
        }

    // id not found.  This shouldn't happen.
    item->current = -1;
}

static MOVFragmentStreamInfo * get_current_frag_stream_info(
    MOVFragmentIndex *frag_index)
{
    MOVFragmentIndexItem *item;
    if (frag_index->current < 0 ||
        frag_index->current >= frag_index->nb_items)
        return NULL;

    item = &frag_index->item[frag_index->current];
    if (item->current >= 0 && item->current < item->nb_stream_info)
        return &item->stream_info[item->current];

    // This shouldn't happen
    return NULL;
}

static int search_frag_moof_offset(MOVFragmentIndex *frag_index, int64_t offset)
{
    int a, b, m;
    int64_t moof_offset;

    // Optimize for appending new entries
    if (!frag_index->nb_items ||
        frag_index->item[frag_index->nb_items - 1].moof_offset < offset)
        return frag_index->nb_items;

    a = -1;
    b = frag_index->nb_items;

    while (b - a > 1) {
        m = (a + b) >> 1;
        moof_offset = frag_index->item[m].moof_offset;
        if (moof_offset >= offset)
            b = m;
        if (moof_offset <= offset)
            a = m;
    }
    return b;
}

static int64_t get_stream_info_time(MOVFragmentStreamInfo * frag_stream_info)
{

    if (frag_stream_info) {
        if (frag_stream_info->sidx_pts != AV_NOPTS_VALUE)
            return frag_stream_info->sidx_pts;
        if (frag_stream_info->first_tfra_pts != AV_NOPTS_VALUE)
            return frag_stream_info->first_tfra_pts;
        if (frag_stream_info->tfdt_dts != AV_NOPTS_VALUE)
            return frag_stream_info->tfdt_dts;
    }
    return AV_NOPTS_VALUE;
}

static int64_t get_frag_time(MOVFragmentIndex *frag_index,
                             int index, int track_id)
{
    MOVFragmentStreamInfo * frag_stream_info;
    int64_t timestamp;
    int i;

    if (track_id >= 0) {
        frag_stream_info = get_frag_stream_info(frag_index, index, track_id);
        return frag_stream_info->sidx_pts;
    }

    for (i = 0; i < frag_index->item[index].nb_stream_info; i++) {
        frag_stream_info = &frag_index->item[index].stream_info[i];
        timestamp = get_stream_info_time(frag_stream_info);
        if (timestamp != AV_NOPTS_VALUE)
            return timestamp;
    }
    return AV_NOPTS_VALUE;
}

static int search_frag_timestamp(MOVFragmentIndex *frag_index,
                                 AVStream *st, int64_t timestamp)
{
    int a, b, m;
    int64_t frag_time;
    int id = -1;

    if (st) {
        // If the stream is referenced by any sidx, limit the search
        // to fragments that referenced this stream in the sidx
        MOVStreamContext *sc = st->priv_data;
        if (sc->has_sidx)
            id = st->id;
    }

    a = -1;
    b = frag_index->nb_items;

    while (b - a > 1) {
        m = (a + b) >> 1;
        frag_time = get_frag_time(frag_index, m, id);
        if (frag_time != AV_NOPTS_VALUE) {
            if (frag_time >= timestamp)
                b = m;
            if (frag_time <= timestamp)
                a = m;
        }
    }
    return a;
}

static int update_frag_index(MOVContext *c, int64_t offset)
{
    int index, i;
    MOVFragmentIndexItem * item;
    MOVFragmentStreamInfo * frag_stream_info;

    // If moof_offset already exists in frag_index, return index to it
    index = search_frag_moof_offset(&c->frag_index, offset);
    if (index < c->frag_index.nb_items &&
        c->frag_index.item[index].moof_offset == offset)
        return index;

    // offset is not yet in frag index.
    // Insert new item at index (sorted by moof offset)
    item = av_fast_realloc(c->frag_index.item,
                           &c->frag_index.allocated_size,
                           (c->frag_index.nb_items + 1) *
                           sizeof(*c->frag_index.item));
    if(!item)
        return -1;
    c->frag_index.item = item;

    frag_stream_info = av_realloc_array(NULL, c->fc->nb_streams,
                                        sizeof(*item->stream_info));
    if (!frag_stream_info)
        return -1;

    for (i = 0; i < c->fc->nb_streams; i++) {
        // Avoid building frag index if streams lack track id.
        if (c->fc->streams[i]->id < 0)
            return AVERROR_INVALIDDATA;

        frag_stream_info[i].id = c->fc->streams[i]->id;
        frag_stream_info[i].sidx_pts = AV_NOPTS_VALUE;
        frag_stream_info[i].tfdt_dts = AV_NOPTS_VALUE;
        frag_stream_info[i].first_tfra_pts = AV_NOPTS_VALUE;
        frag_stream_info[i].index_entry = -1;
    }

    if (index < c->frag_index.nb_items)
        memmove(c->frag_index.item + index + 1, c->frag_index.item + index,
                (c->frag_index.nb_items - index) * sizeof(*c->frag_index.item));

    item = &c->frag_index.item[index];
    item->headers_read = 0;
    item->current = 0;
    item->nb_stream_info = c->fc->nb_streams;
    item->moof_offset = offset;
    item->stream_info = frag_stream_info;
    c->frag_index.nb_items++;

    return index;
}

static void fix_frag_index_entries(MOVFragmentIndex *frag_index, int index,
                                   int id, int entries)
{
    int i;
    MOVFragmentStreamInfo * frag_stream_info;

    if (index < 0)
        return;
    for (i = index; i < frag_index->nb_items; i++) {
        frag_stream_info = get_frag_stream_info(frag_index, i, id);
        if (frag_stream_info && frag_stream_info->index_entry >= 0)
            frag_stream_info->index_entry += entries;
    }
}

static int mov_read_moof(MOVContext *c, AVIOContext *pb, MOVAtom atom)
{
    // Set by mov_read_tfhd(). mov_read_trun() will reject files missing tfhd.
    c->fragment.found_tfhd = 0;

    if (!c->has_looked_for_mfra && c->use_mfra_for > 0) {
        c->has_looked_for_mfra = 1;
        if (pb->seekable & AVIO_SEEKABLE_NORMAL) {
            int ret;
            av_log(c->fc, AV_LOG_VERBOSE, "stream has moof boxes, will look "
                    "for a mfra\n");
            if ((ret = mov_read_mfra(c, pb)) < 0) {
                av_log(c->fc, AV_LOG_VERBOSE, "found a moof box but failed to "
                        "read the mfra (may be a live ismv)\n");
            }
        } else {
            av_log(c->fc, AV_LOG_VERBOSE, "found a moof box but stream is not "
                    "seekable, can not look for mfra\n");
        }
    }
    c->fragment.moof_offset = c->fragment.implicit_offset = avio_tell(pb) - 8;
    av_log(c->fc, AV_LOG_TRACE, "moof offset %"PRIx64"\n", c->fragment.moof_offset);
    c->frag_index.current = update_frag_index(c, c->fragment.moof_offset);
    return mov_read_default(c, pb, atom);
}

static void mov_metadata_creation_time(AVDictionary **metadata, int64_t time)
{
    if (time) {
        if(time >= 2082844800)
            time -= 2082844800;  /* seconds between 1904-01-01 and Epoch */

        if ((int64_t)(time * 1000000ULL) / 1000000 != time) {
            av_log(NULL, AV_LOG_DEBUG, "creation_time is not representable\n");
            return;
        }

        avpriv_dict_set_timestamp(metadata, "creation_time", time * 1000000);
    }
}

static int mov_read_mdhd(MOVContext *c, AVIOContext *pb, MOVAtom atom)
{
    AVStream *st;
    MOVStreamContext *sc;
    int version;
    char language[4] = {0};
    unsigned lang;
    int64_t creation_time;

    if (c->fc->nb_streams < 1)
        return 0;
    st = c->fc->streams[c->fc->nb_streams-1];
    sc = st->priv_data;

    if (sc->time_scale) {
        av_log(c->fc, AV_LOG_ERROR, "Multiple mdhd?\n");
        return AVERROR_INVALIDDATA;
    }

    version = avio_r8(pb);
    if (version > 1) {
        avpriv_request_sample(c->fc, "Version %d", version);
        return AVERROR_PATCHWELCOME;
    }
    avio_rb24(pb); /* flags */
    if (version == 1) {
        creation_time = avio_rb64(pb);
        avio_rb64(pb);
    } else {
        creation_time = avio_rb32(pb);
        avio_rb32(pb); /* modification time */
    }
    mov_metadata_creation_time(&st->metadata, creation_time);

    sc->time_scale = avio_rb32(pb);
    if (sc->time_scale <= 0) {
        av_log(c->fc, AV_LOG_ERROR, "Invalid mdhd time scale %d, defaulting to 1\n", sc->time_scale);
        sc->time_scale = 1;
    }
    st->duration = (version == 1) ? avio_rb64(pb) : avio_rb32(pb); /* duration */

    lang = avio_rb16(pb); /* language */
    if (ff_mov_lang_to_iso639(lang, language))
        av_dict_set(&st->metadata, "language", language, 0);
    avio_rb16(pb); /* quality */

    return 0;
}

static int mov_read_mvhd(MOVContext *c, AVIOContext *pb, MOVAtom atom)
{
    int i;
    int64_t creation_time;
    int version = avio_r8(pb); /* version */
    avio_rb24(pb); /* flags */

    if (version == 1) {
        creation_time = avio_rb64(pb);
        avio_rb64(pb);
    } else {
        creation_time = avio_rb32(pb);
        avio_rb32(pb); /* modification time */
    }
    mov_metadata_creation_time(&c->fc->metadata, creation_time);
    c->time_scale = avio_rb32(pb); /* time scale */
    if (c->time_scale <= 0) {
        av_log(c->fc, AV_LOG_ERROR, "Invalid mvhd time scale %d, defaulting to 1\n", c->time_scale);
        c->time_scale = 1;
    }
    av_log(c->fc, AV_LOG_TRACE, "time scale = %i\n", c->time_scale);

    c->duration = (version == 1) ? avio_rb64(pb) : avio_rb32(pb); /* duration */
    // set the AVCodecContext duration because the duration of individual tracks
    // may be inaccurate
    if (c->time_scale > 0 && !c->trex_data)
        c->fc->duration = av_rescale(c->duration, AV_TIME_BASE, c->time_scale);
    avio_rb32(pb); /* preferred scale */

    avio_rb16(pb); /* preferred volume */

    avio_skip(pb, 10); /* reserved */

    /* movie display matrix, store it in main context and use it later on */
    for (i = 0; i < 3; i++) {
        c->movie_display_matrix[i][0] = avio_rb32(pb); // 16.16 fixed point
        c->movie_display_matrix[i][1] = avio_rb32(pb); // 16.16 fixed point
        c->movie_display_matrix[i][2] = avio_rb32(pb); //  2.30 fixed point
    }

    avio_rb32(pb); /* preview time */
    avio_rb32(pb); /* preview duration */
    avio_rb32(pb); /* poster time */
    avio_rb32(pb); /* selection time */
    avio_rb32(pb); /* selection duration */
    avio_rb32(pb); /* current time */
    avio_rb32(pb); /* next track ID */

    return 0;
}

static int mov_read_enda(MOVContext *c, AVIOContext *pb, MOVAtom atom)
{
    AVStream *st;
    int little_endian;

    if (c->fc->nb_streams < 1)
        return 0;
    st = c->fc->streams[c->fc->nb_streams-1];

    little_endian = avio_rb16(pb) & 0xFF;
    av_log(c->fc, AV_LOG_TRACE, "enda %d\n", little_endian);
    if (little_endian == 1) {
        switch (st->codecpar->codec_id) {
        case AV_CODEC_ID_PCM_S24BE:
            st->codecpar->codec_id = AV_CODEC_ID_PCM_S24LE;
            break;
        case AV_CODEC_ID_PCM_S32BE:
            st->codecpar->codec_id = AV_CODEC_ID_PCM_S32LE;
            break;
        case AV_CODEC_ID_PCM_F32BE:
            st->codecpar->codec_id = AV_CODEC_ID_PCM_F32LE;
            break;
        case AV_CODEC_ID_PCM_F64BE:
            st->codecpar->codec_id = AV_CODEC_ID_PCM_F64LE;
            break;
        default:
            break;
        }
    }
    return 0;
}

static int mov_read_colr(MOVContext *c, AVIOContext *pb, MOVAtom atom)
{
    AVStream *st;
    char color_parameter_type[5] = { 0 };
    uint16_t color_primaries, color_trc, color_matrix;
    int ret;

    if (c->fc->nb_streams < 1)
        return 0;
    st = c->fc->streams[c->fc->nb_streams - 1];

    ret = ffio_read_size(pb, color_parameter_type, 4);
    if (ret < 0)
        return ret;
    if (strncmp(color_parameter_type, "nclx", 4) &&
        strncmp(color_parameter_type, "nclc", 4)) {
        av_log(c->fc, AV_LOG_WARNING, "unsupported color_parameter_type %s\n",
               color_parameter_type);
        return 0;
    }

    color_primaries = avio_rb16(pb);
    color_trc = avio_rb16(pb);
    color_matrix = avio_rb16(pb);

    av_log(c->fc, AV_LOG_TRACE,
           "%s: pri %d trc %d matrix %d",
           color_parameter_type, color_primaries, color_trc, color_matrix);

    if (!strncmp(color_parameter_type, "nclx", 4)) {
        uint8_t color_range = avio_r8(pb) >> 7;
        av_log(c->fc, AV_LOG_TRACE, " full %"PRIu8"", color_range);
        if (color_range)
            st->codecpar->color_range = AVCOL_RANGE_JPEG;
        else
            st->codecpar->color_range = AVCOL_RANGE_MPEG;
    }

    if (!av_color_primaries_name(color_primaries))
        color_primaries = AVCOL_PRI_UNSPECIFIED;
    if (!av_color_transfer_name(color_trc))
        color_trc = AVCOL_TRC_UNSPECIFIED;
    if (!av_color_space_name(color_matrix))
        color_matrix = AVCOL_SPC_UNSPECIFIED;

    st->codecpar->color_primaries = color_primaries;
    st->codecpar->color_trc       = color_trc;
    st->codecpar->color_space     = color_matrix;
    av_log(c->fc, AV_LOG_TRACE, "\n");

    return 0;
}

static int mov_read_fiel(MOVContext *c, AVIOContext *pb, MOVAtom atom)
{
    AVStream *st;
    unsigned mov_field_order;
    enum AVFieldOrder decoded_field_order = AV_FIELD_UNKNOWN;

    if (c->fc->nb_streams < 1) // will happen with jp2 files
        return 0;
    st = c->fc->streams[c->fc->nb_streams-1];
    if (atom.size < 2)
        return AVERROR_INVALIDDATA;
    mov_field_order = avio_rb16(pb);
    if ((mov_field_order & 0xFF00) == 0x0100)
        decoded_field_order = AV_FIELD_PROGRESSIVE;
    else if ((mov_field_order & 0xFF00) == 0x0200) {
        switch (mov_field_order & 0xFF) {
        case 0x01: decoded_field_order = AV_FIELD_TT;
                   break;
        case 0x06: decoded_field_order = AV_FIELD_BB;
                   break;
        case 0x09: decoded_field_order = AV_FIELD_TB;
                   break;
        case 0x0E: decoded_field_order = AV_FIELD_BT;
                   break;
        }
    }
    if (decoded_field_order == AV_FIELD_UNKNOWN && mov_field_order) {
        av_log(NULL, AV_LOG_ERROR, "Unknown MOV field order 0x%04x\n", mov_field_order);
    }
    st->codecpar->field_order = decoded_field_order;

    return 0;
}

static int mov_realloc_extradata(AVCodecParameters *par, MOVAtom atom)
{
    int err = 0;
    uint64_t size = (uint64_t)par->extradata_size + atom.size + 8 + AV_INPUT_BUFFER_PADDING_SIZE;
    if (size > INT_MAX || (uint64_t)atom.size > INT_MAX)
        return AVERROR_INVALIDDATA;
    if ((err = av_reallocp(&par->extradata, size)) < 0) {
        par->extradata_size = 0;
        return err;
    }
    par->extradata_size = size - AV_INPUT_BUFFER_PADDING_SIZE;
    return 0;
}

/* Read a whole atom into the extradata return the size of the atom read, possibly truncated if != atom.size */
static int64_t mov_read_atom_into_extradata(MOVContext *c, AVIOContext *pb, MOVAtom atom,
                                        AVCodecParameters *par, uint8_t *buf)
{
    int64_t result = atom.size;
    int err;

    AV_WB32(buf    , atom.size + 8);
    AV_WL32(buf + 4, atom.type);
    err = ffio_read_size(pb, buf + 8, atom.size);
    if (err < 0) {
        par->extradata_size -= atom.size;
        return err;
    } else if (err < atom.size) {
        av_log(c->fc, AV_LOG_WARNING, "truncated extradata\n");
        par->extradata_size -= atom.size - err;
        result = err;
    }
    memset(buf + 8 + err, 0, AV_INPUT_BUFFER_PADDING_SIZE);
    return result;
}

/* FIXME modify QDM2/SVQ3/H.264 decoders to take full atom as extradata */
static int mov_read_extradata(MOVContext *c, AVIOContext *pb, MOVAtom atom,
                              enum AVCodecID codec_id)
{
    AVStream *st;
    uint64_t original_size;
    int err;

    if (c->fc->nb_streams < 1) // will happen with jp2 files
        return 0;
    st = c->fc->streams[c->fc->nb_streams-1];

    if (st->codecpar->codec_id != codec_id)
        return 0; /* unexpected codec_id - don't mess with extradata */

    original_size = st->codecpar->extradata_size;
    err = mov_realloc_extradata(st->codecpar, atom);
    if (err)
        return err;

    err =  mov_read_atom_into_extradata(c, pb, atom, st->codecpar,  st->codecpar->extradata + original_size);
    if (err < 0)
        return err;
    return 0; // Note: this is the original behavior to ignore truncation.
}

/* wrapper functions for reading ALAC/AVS/MJPEG/MJPEG2000 extradata atoms only for those codecs */
static int mov_read_alac(MOVContext *c, AVIOContext *pb, MOVAtom atom)
{
    return mov_read_extradata(c, pb, atom, AV_CODEC_ID_ALAC);
}

static int mov_read_avss(MOVContext *c, AVIOContext *pb, MOVAtom atom)
{
    return mov_read_extradata(c, pb, atom, AV_CODEC_ID_AVS);
}

static int mov_read_jp2h(MOVContext *c, AVIOContext *pb, MOVAtom atom)
{
    return mov_read_extradata(c, pb, atom, AV_CODEC_ID_JPEG2000);
}

static int mov_read_dpxe(MOVContext *c, AVIOContext *pb, MOVAtom atom)
{
    return mov_read_extradata(c, pb, atom, AV_CODEC_ID_R10K);
}

static int mov_read_avid(MOVContext *c, AVIOContext *pb, MOVAtom atom)
{
    int ret = mov_read_extradata(c, pb, atom, AV_CODEC_ID_AVUI);
    if(ret == 0)
        ret = mov_read_extradata(c, pb, atom, AV_CODEC_ID_DNXHD);
    return ret;
}

static int mov_read_targa_y216(MOVContext *c, AVIOContext *pb, MOVAtom atom)
{
    int ret = mov_read_extradata(c, pb, atom, AV_CODEC_ID_TARGA_Y216);

    if (!ret && c->fc->nb_streams >= 1) {
        AVCodecParameters *par = c->fc->streams[c->fc->nb_streams-1]->codecpar;
        if (par->extradata_size >= 40) {
            par->height = AV_RB16(&par->extradata[36]);
            par->width  = AV_RB16(&par->extradata[38]);
        }
    }
    return ret;
}

static int mov_read_ares(MOVContext *c, AVIOContext *pb, MOVAtom atom)
{
    if (c->fc->nb_streams >= 1) {
        AVCodecParameters *par = c->fc->streams[c->fc->nb_streams-1]->codecpar;
        if (par->codec_tag == MKTAG('A', 'V', 'i', 'n') &&
            par->codec_id == AV_CODEC_ID_H264 &&
            atom.size > 11) {
            int cid;
            avio_skip(pb, 10);
            cid = avio_rb16(pb);
            /* For AVID AVCI50, force width of 1440 to be able to select the correct SPS and PPS */
            if (cid == 0xd4d || cid == 0xd4e)
                par->width = 1440;
            return 0;
        } else if ((par->codec_tag == MKTAG('A', 'V', 'd', '1') ||
                    par->codec_tag == MKTAG('A', 'V', 'j', '2') ||
                    par->codec_tag == MKTAG('A', 'V', 'd', 'n')) &&
                   atom.size >= 24) {
            int num, den;
            avio_skip(pb, 12);
            num = avio_rb32(pb);
            den = avio_rb32(pb);
            if (num <= 0 || den <= 0)
                return 0;
            switch (avio_rb32(pb)) {
            case 2:
                if (den >= INT_MAX / 2)
                    return 0;
                den *= 2;
            case 1:
                c->fc->streams[c->fc->nb_streams-1]->display_aspect_ratio.num = num;
                c->fc->streams[c->fc->nb_streams-1]->display_aspect_ratio.den = den;
            default:
                return 0;
            }
        }
    }

    return mov_read_avid(c, pb, atom);
}

static int mov_read_aclr(MOVContext *c, AVIOContext *pb, MOVAtom atom)
{
    int ret = 0;
    int length = 0;
    uint64_t original_size;
    if (c->fc->nb_streams >= 1) {
        AVCodecParameters *par = c->fc->streams[c->fc->nb_streams-1]->codecpar;
        if (par->codec_id == AV_CODEC_ID_H264)
            return 0;
        if (atom.size == 16) {
            original_size = par->extradata_size;
            ret = mov_realloc_extradata(par, atom);
            if (!ret) {
                length =  mov_read_atom_into_extradata(c, pb, atom, par, par->extradata + original_size);
                if (length == atom.size) {
                    const uint8_t range_value = par->extradata[original_size + 19];
                    switch (range_value) {
                    case 1:
                        par->color_range = AVCOL_RANGE_MPEG;
                        break;
                    case 2:
                        par->color_range = AVCOL_RANGE_JPEG;
                        break;
                    default:
                        av_log(c, AV_LOG_WARNING, "ignored unknown aclr value (%d)\n", range_value);
                        break;
                    }
                    ff_dlog(c, "color_range: %d\n", par->color_range);
                } else {
                  /* For some reason the whole atom was not added to the extradata */
                  av_log(c, AV_LOG_ERROR, "aclr not decoded - incomplete atom\n");
                }
            } else {
                av_log(c, AV_LOG_ERROR, "aclr not decoded - unable to add atom to extradata\n");
            }
        } else {
            av_log(c, AV_LOG_WARNING, "aclr not decoded - unexpected size %"PRId64"\n", atom.size);
        }
    }

    return ret;
}

static int mov_read_svq3(MOVContext *c, AVIOContext *pb, MOVAtom atom)
{
    return mov_read_extradata(c, pb, atom, AV_CODEC_ID_SVQ3);
}

static int mov_read_wave(MOVContext *c, AVIOContext *pb, MOVAtom atom)
{
    AVStream *st;
    int ret;

    if (c->fc->nb_streams < 1)
        return 0;
    st = c->fc->streams[c->fc->nb_streams-1];

    if ((uint64_t)atom.size > (1<<30))
        return AVERROR_INVALIDDATA;

    if (st->codecpar->codec_id == AV_CODEC_ID_QDM2 ||
        st->codecpar->codec_id == AV_CODEC_ID_QDMC ||
        st->codecpar->codec_id == AV_CODEC_ID_SPEEX) {
        // pass all frma atom to codec, needed at least for QDMC and QDM2
        av_freep(&st->codecpar->extradata);
        ret = ff_get_extradata(c->fc, st->codecpar, pb, atom.size);
        if (ret < 0)
            return ret;
    } else if (atom.size > 8) { /* to read frma, esds atoms */
        if (st->codecpar->codec_id == AV_CODEC_ID_ALAC && atom.size >= 24) {
            uint64_t buffer;
            ret = ffio_ensure_seekback(pb, 8);
            if (ret < 0)
                return ret;
            buffer = avio_rb64(pb);
            atom.size -= 8;
            if (  (buffer & 0xFFFFFFFF) == MKBETAG('f','r','m','a')
                && buffer >> 32 <= atom.size
                && buffer >> 32 >= 8) {
                avio_skip(pb, -8);
                atom.size += 8;
            } else if (!st->codecpar->extradata_size) {
#define ALAC_EXTRADATA_SIZE 36
                st->codecpar->extradata = av_mallocz(ALAC_EXTRADATA_SIZE + AV_INPUT_BUFFER_PADDING_SIZE);
                if (!st->codecpar->extradata)
                    return AVERROR(ENOMEM);
                st->codecpar->extradata_size = ALAC_EXTRADATA_SIZE;
                AV_WB32(st->codecpar->extradata    , ALAC_EXTRADATA_SIZE);
                AV_WB32(st->codecpar->extradata + 4, MKTAG('a','l','a','c'));
                AV_WB64(st->codecpar->extradata + 12, buffer);
                avio_read(pb, st->codecpar->extradata + 20, 16);
                avio_skip(pb, atom.size - 24);
                return 0;
            }
        }
        if ((ret = mov_read_default(c, pb, atom)) < 0)
            return ret;
    } else
        avio_skip(pb, atom.size);
    return 0;
}

/**
 * This function reads atom content and puts data in extradata without tag
 * nor size unlike mov_read_extradata.
 */
static int mov_read_glbl(MOVContext *c, AVIOContext *pb, MOVAtom atom)
{
    AVStream *st;
    int ret;

    if (c->fc->nb_streams < 1)
        return 0;
    st = c->fc->streams[c->fc->nb_streams-1];

    if ((uint64_t)atom.size > (1<<30))
        return AVERROR_INVALIDDATA;

    if (atom.size >= 10) {
        // Broken files created by legacy versions of libavformat will
        // wrap a whole fiel atom inside of a glbl atom.
        unsigned size = avio_rb32(pb);
        unsigned type = avio_rl32(pb);
        avio_seek(pb, -8, SEEK_CUR);
        if (type == MKTAG('f','i','e','l') && size == atom.size)
            return mov_read_default(c, pb, atom);
    }
    if (st->codecpar->extradata_size > 1 && st->codecpar->extradata) {
        av_log(c, AV_LOG_WARNING, "ignoring multiple glbl\n");
        return 0;
    }
    av_freep(&st->codecpar->extradata);
    ret = ff_get_extradata(c->fc, st->codecpar, pb, atom.size);
    if (ret < 0)
        return ret;

    return 0;
}

static int mov_read_dvc1(MOVContext *c, AVIOContext *pb, MOVAtom atom)
{
    AVStream *st;
    uint8_t profile_level;
    int ret;

    if (c->fc->nb_streams < 1)
        return 0;
    st = c->fc->streams[c->fc->nb_streams-1];

    if (atom.size >= (1<<28) || atom.size < 7)
        return AVERROR_INVALIDDATA;

    profile_level = avio_r8(pb);
    if ((profile_level & 0xf0) != 0xc0)
        return 0;

    avio_seek(pb, 6, SEEK_CUR);
    av_freep(&st->codecpar->extradata);
    ret = ff_get_extradata(c->fc, st->codecpar, pb, atom.size - 7);
    if (ret < 0)
        return ret;

    return 0;
}

/**
 * An strf atom is a BITMAPINFOHEADER struct. This struct is 40 bytes itself,
 * but can have extradata appended at the end after the 40 bytes belonging
 * to the struct.
 */
static int mov_read_strf(MOVContext *c, AVIOContext *pb, MOVAtom atom)
{
    AVStream *st;
    int ret;

    if (c->fc->nb_streams < 1)
        return 0;
    if (atom.size <= 40)
        return 0;
    st = c->fc->streams[c->fc->nb_streams-1];

    if ((uint64_t)atom.size > (1<<30))
        return AVERROR_INVALIDDATA;

    avio_skip(pb, 40);
    av_freep(&st->codecpar->extradata);
    ret = ff_get_extradata(c->fc, st->codecpar, pb, atom.size - 40);
    if (ret < 0)
        return ret;

    return 0;
}

static int mov_read_stco(MOVContext *c, AVIOContext *pb, MOVAtom atom)
{
    AVStream *st;
    MOVStreamContext *sc;
    unsigned int i, entries;

    if (c->fc->nb_streams < 1)
        return 0;
    st = c->fc->streams[c->fc->nb_streams-1];
    sc = st->priv_data;

    avio_r8(pb); /* version */
    avio_rb24(pb); /* flags */

    entries = avio_rb32(pb);

    if (!entries)
        return 0;

    if (sc->chunk_offsets)
        av_log(c->fc, AV_LOG_WARNING, "Duplicated STCO atom\n");
    av_free(sc->chunk_offsets);
    sc->chunk_count = 0;
    sc->chunk_offsets = av_malloc_array(entries, sizeof(*sc->chunk_offsets));
    if (!sc->chunk_offsets)
        return AVERROR(ENOMEM);
    sc->chunk_count = entries;

    if      (atom.type == MKTAG('s','t','c','o'))
        for (i = 0; i < entries && !pb->eof_reached; i++)
            sc->chunk_offsets[i] = avio_rb32(pb);
    else if (atom.type == MKTAG('c','o','6','4'))
        for (i = 0; i < entries && !pb->eof_reached; i++)
            sc->chunk_offsets[i] = avio_rb64(pb);
    else
        return AVERROR_INVALIDDATA;

    sc->chunk_count = i;

    if (pb->eof_reached) {
        av_log(c->fc, AV_LOG_WARNING, "reached eof, corrupted STCO atom\n");
        return AVERROR_EOF;
    }

    return 0;
}

static int mov_codec_id(AVStream *st, uint32_t format)
{
    int id = ff_codec_get_id(ff_codec_movaudio_tags, format);

    if (id <= 0 &&
        ((format & 0xFFFF) == 'm' + ('s' << 8) ||
         (format & 0xFFFF) == 'T' + ('S' << 8)))
        id = ff_codec_get_id(ff_codec_wav_tags, av_bswap32(format) & 0xFFFF);

    if (st->codecpar->codec_type != AVMEDIA_TYPE_VIDEO && id > 0) {
        st->codecpar->codec_type = AVMEDIA_TYPE_AUDIO;
    } else if (st->codecpar->codec_type != AVMEDIA_TYPE_AUDIO &&
               /* skip old ASF MPEG-4 tag */
               format && format != MKTAG('m','p','4','s')) {
        id = ff_codec_get_id(ff_codec_movvideo_tags, format);
        if (id <= 0)
            id = ff_codec_get_id(ff_codec_bmp_tags, format);
        if (id > 0)
            st->codecpar->codec_type = AVMEDIA_TYPE_VIDEO;
        else if (st->codecpar->codec_type == AVMEDIA_TYPE_DATA ||
                    (st->codecpar->codec_type == AVMEDIA_TYPE_SUBTITLE &&
                    st->codecpar->codec_id == AV_CODEC_ID_NONE)) {
            id = ff_codec_get_id(ff_codec_movsubtitle_tags, format);
            if (id > 0)
                st->codecpar->codec_type = AVMEDIA_TYPE_SUBTITLE;
        }
    }

    st->codecpar->codec_tag = format;

    return id;
}

static void mov_parse_stsd_video(MOVContext *c, AVIOContext *pb,
                                 AVStream *st, MOVStreamContext *sc)
{
    uint8_t codec_name[32] = { 0 };
    int64_t stsd_start;
    unsigned int len;

    /* The first 16 bytes of the video sample description are already
     * read in ff_mov_read_stsd_entries() */
    stsd_start = avio_tell(pb) - 16;

    avio_rb16(pb); /* version */
    avio_rb16(pb); /* revision level */
    avio_rb32(pb); /* vendor */
    avio_rb32(pb); /* temporal quality */
    avio_rb32(pb); /* spatial quality */

    st->codecpar->width  = avio_rb16(pb); /* width */
    st->codecpar->height = avio_rb16(pb); /* height */

    avio_rb32(pb); /* horiz resolution */
    avio_rb32(pb); /* vert resolution */
    avio_rb32(pb); /* data size, always 0 */
    avio_rb16(pb); /* frames per samples */

    len = avio_r8(pb); /* codec name, pascal string */
    if (len > 31)
        len = 31;
    mov_read_mac_string(c, pb, len, codec_name, sizeof(codec_name));
    if (len < 31)
        avio_skip(pb, 31 - len);

    if (codec_name[0])
        av_dict_set(&st->metadata, "encoder", codec_name, 0);

    /* codec_tag YV12 triggers an UV swap in rawdec.c */
    if (!strncmp(codec_name, "Planar Y'CbCr 8-bit 4:2:0", 25)) {
        st->codecpar->codec_tag = MKTAG('I', '4', '2', '0');
        st->codecpar->width &= ~1;
        st->codecpar->height &= ~1;
    }
    /* Flash Media Server uses tag H.263 with Sorenson Spark */
    if (st->codecpar->codec_tag == MKTAG('H','2','6','3') &&
        !strncmp(codec_name, "Sorenson H263", 13))
        st->codecpar->codec_id = AV_CODEC_ID_FLV1;

    st->codecpar->bits_per_coded_sample = avio_rb16(pb); /* depth */

    avio_seek(pb, stsd_start, SEEK_SET);

    if (ff_get_qtpalette(st->codecpar->codec_id, pb, sc->palette)) {
        st->codecpar->bits_per_coded_sample &= 0x1F;
        sc->has_palette = 1;
    }
}

static void mov_parse_stsd_audio(MOVContext *c, AVIOContext *pb,
                                 AVStream *st, MOVStreamContext *sc)
{
    int bits_per_sample, flags;
    uint16_t version = avio_rb16(pb);
    AVDictionaryEntry *compatible_brands = av_dict_get(c->fc->metadata, "compatible_brands", NULL, AV_DICT_MATCH_CASE);

    avio_rb16(pb); /* revision level */
    avio_rb32(pb); /* vendor */

    st->codecpar->channels              = avio_rb16(pb); /* channel count */
    st->codecpar->bits_per_coded_sample = avio_rb16(pb); /* sample size */
    av_log(c->fc, AV_LOG_TRACE, "audio channels %d\n", st->codecpar->channels);

    sc->audio_cid = avio_rb16(pb);
    avio_rb16(pb); /* packet size = 0 */

    st->codecpar->sample_rate = ((avio_rb32(pb) >> 16));

    // Read QT version 1 fields. In version 0 these do not exist.
    av_log(c->fc, AV_LOG_TRACE, "version =%d, isom =%d\n", version, c->isom);
    if (!c->isom ||
        (compatible_brands && strstr(compatible_brands->value, "qt  "))) {

        if (version == 1) {
            sc->samples_per_frame = avio_rb32(pb);
            avio_rb32(pb); /* bytes per packet */
            sc->bytes_per_frame = avio_rb32(pb);
            avio_rb32(pb); /* bytes per sample */
        } else if (version == 2) {
            avio_rb32(pb); /* sizeof struct only */
            st->codecpar->sample_rate = av_int2double(avio_rb64(pb));
            st->codecpar->channels    = avio_rb32(pb);
            avio_rb32(pb); /* always 0x7F000000 */
            st->codecpar->bits_per_coded_sample = avio_rb32(pb);

            flags = avio_rb32(pb); /* lpcm format specific flag */
            sc->bytes_per_frame   = avio_rb32(pb);
            sc->samples_per_frame = avio_rb32(pb);
            if (st->codecpar->codec_tag == MKTAG('l','p','c','m'))
                st->codecpar->codec_id =
                    ff_mov_get_lpcm_codec_id(st->codecpar->bits_per_coded_sample,
                                             flags);
        }
        if (version == 0 || (version == 1 && sc->audio_cid != -2)) {
            /* can't correctly handle variable sized packet as audio unit */
            switch (st->codecpar->codec_id) {
            case AV_CODEC_ID_MP2:
            case AV_CODEC_ID_MP3:
                st->need_parsing = AVSTREAM_PARSE_FULL;
                break;
            }
        }
    }

    if (sc->format == 0) {
        if (st->codecpar->bits_per_coded_sample == 8)
            st->codecpar->codec_id = mov_codec_id(st, MKTAG('r','a','w',' '));
        else if (st->codecpar->bits_per_coded_sample == 16)
            st->codecpar->codec_id = mov_codec_id(st, MKTAG('t','w','o','s'));
    }

    switch (st->codecpar->codec_id) {
    case AV_CODEC_ID_PCM_S8:
    case AV_CODEC_ID_PCM_U8:
        if (st->codecpar->bits_per_coded_sample == 16)
            st->codecpar->codec_id = AV_CODEC_ID_PCM_S16BE;
        break;
    case AV_CODEC_ID_PCM_S16LE:
    case AV_CODEC_ID_PCM_S16BE:
        if (st->codecpar->bits_per_coded_sample == 8)
            st->codecpar->codec_id = AV_CODEC_ID_PCM_S8;
        else if (st->codecpar->bits_per_coded_sample == 24)
            st->codecpar->codec_id =
                st->codecpar->codec_id == AV_CODEC_ID_PCM_S16BE ?
                AV_CODEC_ID_PCM_S24BE : AV_CODEC_ID_PCM_S24LE;
        else if (st->codecpar->bits_per_coded_sample == 32)
             st->codecpar->codec_id =
                st->codecpar->codec_id == AV_CODEC_ID_PCM_S16BE ?
                AV_CODEC_ID_PCM_S32BE : AV_CODEC_ID_PCM_S32LE;
        break;
    /* set values for old format before stsd version 1 appeared */
    case AV_CODEC_ID_MACE3:
        sc->samples_per_frame = 6;
        sc->bytes_per_frame   = 2 * st->codecpar->channels;
        break;
    case AV_CODEC_ID_MACE6:
        sc->samples_per_frame = 6;
        sc->bytes_per_frame   = 1 * st->codecpar->channels;
        break;
    case AV_CODEC_ID_ADPCM_IMA_QT:
        sc->samples_per_frame = 64;
        sc->bytes_per_frame   = 34 * st->codecpar->channels;
        break;
    case AV_CODEC_ID_GSM:
        sc->samples_per_frame = 160;
        sc->bytes_per_frame   = 33;
        break;
    default:
        break;
    }

    bits_per_sample = av_get_bits_per_sample(st->codecpar->codec_id);
    if (bits_per_sample) {
        st->codecpar->bits_per_coded_sample = bits_per_sample;
        sc->sample_size = (bits_per_sample >> 3) * st->codecpar->channels;
    }
}

static void mov_parse_stsd_subtitle(MOVContext *c, AVIOContext *pb,
                                    AVStream *st, MOVStreamContext *sc,
                                    int64_t size)
{
    // ttxt stsd contains display flags, justification, background
    // color, fonts, and default styles, so fake an atom to read it
    MOVAtom fake_atom = { .size = size };
    // mp4s contains a regular esds atom
    if (st->codecpar->codec_tag != AV_RL32("mp4s"))
        mov_read_glbl(c, pb, fake_atom);
    st->codecpar->width  = sc->width;
    st->codecpar->height = sc->height;
}

static uint32_t yuv_to_rgba(uint32_t ycbcr)
{
    uint8_t r, g, b;
    int y, cb, cr;

    y  = (ycbcr >> 16) & 0xFF;
    cr = (ycbcr >> 8)  & 0xFF;
    cb =  ycbcr        & 0xFF;

    b = av_clip_uint8((1164 * (y - 16)                     + 2018 * (cb - 128)) / 1000);
    g = av_clip_uint8((1164 * (y - 16) -  813 * (cr - 128) -  391 * (cb - 128)) / 1000);
    r = av_clip_uint8((1164 * (y - 16) + 1596 * (cr - 128)                    ) / 1000);

    return (r << 16) | (g << 8) | b;
}

static int mov_rewrite_dvd_sub_extradata(AVStream *st)
{
    char buf[256] = {0};
    uint8_t *src = st->codecpar->extradata;
    int i;

    if (st->codecpar->extradata_size != 64)
        return 0;

    if (st->codecpar->width > 0 &&  st->codecpar->height > 0)
        snprintf(buf, sizeof(buf), "size: %dx%d\n",
                 st->codecpar->width, st->codecpar->height);
    av_strlcat(buf, "palette: ", sizeof(buf));

    for (i = 0; i < 16; i++) {
        uint32_t yuv = AV_RB32(src + i * 4);
        uint32_t rgba = yuv_to_rgba(yuv);

        av_strlcatf(buf, sizeof(buf), "%06"PRIx32"%s", rgba, i != 15 ? ", " : "");
    }

    if (av_strlcat(buf, "\n", sizeof(buf)) >= sizeof(buf))
        return 0;

    av_freep(&st->codecpar->extradata);
    st->codecpar->extradata_size = 0;
    st->codecpar->extradata = av_mallocz(strlen(buf) + AV_INPUT_BUFFER_PADDING_SIZE);
    if (!st->codecpar->extradata)
        return AVERROR(ENOMEM);
    st->codecpar->extradata_size = strlen(buf);
    memcpy(st->codecpar->extradata, buf, st->codecpar->extradata_size);

    return 0;
}

static int mov_parse_stsd_data(MOVContext *c, AVIOContext *pb,
                                AVStream *st, MOVStreamContext *sc,
                                int64_t size)
{
    int ret;

    if (st->codecpar->codec_tag == MKTAG('t','m','c','d')) {
        if ((int)size != size)
            return AVERROR(ENOMEM);

        ret = ff_get_extradata(c->fc, st->codecpar, pb, size);
        if (ret < 0)
            return ret;
        if (size > 16) {
            MOVStreamContext *tmcd_ctx = st->priv_data;
            int val;
            val = AV_RB32(st->codecpar->extradata + 4);
            tmcd_ctx->tmcd_flags = val;
            st->avg_frame_rate.num = st->codecpar->extradata[16]; /* number of frame */
            st->avg_frame_rate.den = 1;
#if FF_API_LAVF_AVCTX
FF_DISABLE_DEPRECATION_WARNINGS
            st->codec->time_base = av_inv_q(st->avg_frame_rate);
FF_ENABLE_DEPRECATION_WARNINGS
#endif
            /* adjust for per frame dur in counter mode */
            if (tmcd_ctx->tmcd_flags & 0x0008) {
                int timescale = AV_RB32(st->codecpar->extradata + 8);
                int framedur = AV_RB32(st->codecpar->extradata + 12);
                st->avg_frame_rate.num *= timescale;
                st->avg_frame_rate.den *= framedur;
#if FF_API_LAVF_AVCTX
FF_DISABLE_DEPRECATION_WARNINGS
                st->codec->time_base.den *= timescale;
                st->codec->time_base.num *= framedur;
FF_ENABLE_DEPRECATION_WARNINGS
#endif
            }
            if (size > 30) {
                uint32_t len = AV_RB32(st->codecpar->extradata + 18); /* name atom length */
                uint32_t format = AV_RB32(st->codecpar->extradata + 22);
                if (format == AV_RB32("name") && (int64_t)size >= (int64_t)len + 18) {
                    uint16_t str_size = AV_RB16(st->codecpar->extradata + 26); /* string length */
                    if (str_size > 0 && size >= (int)str_size + 26) {
                        char *reel_name = av_malloc(str_size + 1);
                        if (!reel_name)
                            return AVERROR(ENOMEM);
                        memcpy(reel_name, st->codecpar->extradata + 30, str_size);
                        reel_name[str_size] = 0; /* Add null terminator */
                        /* don't add reel_name if emtpy string */
                        if (*reel_name == 0) {
                            av_free(reel_name);
                        } else {
                            av_dict_set(&st->metadata, "reel_name", reel_name,  AV_DICT_DONT_STRDUP_VAL);
                        }
                    }
                }
            }
        }
    } else {
        /* other codec type, just skip (rtp, mp4s ...) */
        avio_skip(pb, size);
    }
    return 0;
}

static int mov_finalize_stsd_codec(MOVContext *c, AVIOContext *pb,
                                   AVStream *st, MOVStreamContext *sc)
{
    if (st->codecpar->codec_type == AVMEDIA_TYPE_AUDIO &&
        !st->codecpar->sample_rate && sc->time_scale > 1)
        st->codecpar->sample_rate = sc->time_scale;

    /* special codec parameters handling */
    switch (st->codecpar->codec_id) {
#if CONFIG_DV_DEMUXER
    case AV_CODEC_ID_DVAUDIO:
        c->dv_fctx = avformat_alloc_context();
        if (!c->dv_fctx) {
            av_log(c->fc, AV_LOG_ERROR, "dv demux context alloc error\n");
            return AVERROR(ENOMEM);
        }
        c->dv_demux = avpriv_dv_init_demux(c->dv_fctx);
        if (!c->dv_demux) {
            av_log(c->fc, AV_LOG_ERROR, "dv demux context init error\n");
            return AVERROR(ENOMEM);
        }
        sc->dv_audio_container = 1;
        st->codecpar->codec_id    = AV_CODEC_ID_PCM_S16LE;
        break;
#endif
    /* no ifdef since parameters are always those */
    case AV_CODEC_ID_QCELP:
        st->codecpar->channels = 1;
        // force sample rate for qcelp when not stored in mov
        if (st->codecpar->codec_tag != MKTAG('Q','c','l','p'))
            st->codecpar->sample_rate = 8000;
        // FIXME: Why is the following needed for some files?
        sc->samples_per_frame = 160;
        if (!sc->bytes_per_frame)
            sc->bytes_per_frame = 35;
        break;
    case AV_CODEC_ID_AMR_NB:
        st->codecpar->channels    = 1;
        /* force sample rate for amr, stsd in 3gp does not store sample rate */
        st->codecpar->sample_rate = 8000;
        break;
    case AV_CODEC_ID_AMR_WB:
        st->codecpar->channels    = 1;
        st->codecpar->sample_rate = 16000;
        break;
    case AV_CODEC_ID_MP2:
    case AV_CODEC_ID_MP3:
        /* force type after stsd for m1a hdlr */
        st->codecpar->codec_type = AVMEDIA_TYPE_AUDIO;
        break;
    case AV_CODEC_ID_GSM:
    case AV_CODEC_ID_ADPCM_MS:
    case AV_CODEC_ID_ADPCM_IMA_WAV:
    case AV_CODEC_ID_ILBC:
    case AV_CODEC_ID_MACE3:
    case AV_CODEC_ID_MACE6:
    case AV_CODEC_ID_QDM2:
        st->codecpar->block_align = sc->bytes_per_frame;
        break;
    case AV_CODEC_ID_ALAC:
        if (st->codecpar->extradata_size == 36) {
            st->codecpar->channels    = AV_RB8 (st->codecpar->extradata + 21);
            st->codecpar->sample_rate = AV_RB32(st->codecpar->extradata + 32);
        }
        break;
    case AV_CODEC_ID_AC3:
    case AV_CODEC_ID_EAC3:
    case AV_CODEC_ID_MPEG1VIDEO:
    case AV_CODEC_ID_VC1:
    case AV_CODEC_ID_VP8:
    case AV_CODEC_ID_VP9:
        st->need_parsing = AVSTREAM_PARSE_FULL;
        break;
    default:
        break;
    }
    return 0;
}

static int mov_skip_multiple_stsd(MOVContext *c, AVIOContext *pb,
                                  int codec_tag, int format,
                                  int64_t size)
{
    int video_codec_id = ff_codec_get_id(ff_codec_movvideo_tags, format);

    if (codec_tag &&
         (codec_tag != format &&
          // AVID 1:1 samples with differing data format and codec tag exist
          (codec_tag != AV_RL32("AV1x") || format != AV_RL32("AVup")) &&
          // prores is allowed to have differing data format and codec tag
          codec_tag != AV_RL32("apcn") && codec_tag != AV_RL32("apch") &&
          // so is dv (sigh)
          codec_tag != AV_RL32("dvpp") && codec_tag != AV_RL32("dvcp") &&
          (c->fc->video_codec_id ? video_codec_id != c->fc->video_codec_id
                                 : codec_tag != MKTAG('j','p','e','g')))) {
        /* Multiple fourcc, we skip JPEG. This is not correct, we should
         * export it as a separate AVStream but this needs a few changes
         * in the MOV demuxer, patch welcome. */

        av_log(c->fc, AV_LOG_WARNING, "multiple fourcc not supported\n");
        avio_skip(pb, size);
        return 1;
    }

    return 0;
}

int ff_mov_read_stsd_entries(MOVContext *c, AVIOContext *pb, int entries)
{
    AVStream *st;
    MOVStreamContext *sc;
    int pseudo_stream_id;

    av_assert0 (c->fc->nb_streams >= 1);
    st = c->fc->streams[c->fc->nb_streams-1];
    sc = st->priv_data;

    for (pseudo_stream_id = 0;
         pseudo_stream_id < entries && !pb->eof_reached;
         pseudo_stream_id++) {
        //Parsing Sample description table
        enum AVCodecID id;
        int ret, dref_id = 1;
        MOVAtom a = { AV_RL32("stsd") };
        int64_t start_pos = avio_tell(pb);
        int64_t size    = avio_rb32(pb); /* size */
        uint32_t format = avio_rl32(pb); /* data format */

        if (size >= 16) {
            avio_rb32(pb); /* reserved */
            avio_rb16(pb); /* reserved */
            dref_id = avio_rb16(pb);
        } else if (size <= 7) {
            av_log(c->fc, AV_LOG_ERROR,
                   "invalid size %"PRId64" in stsd\n", size);
            return AVERROR_INVALIDDATA;
        }

        if (mov_skip_multiple_stsd(c, pb, st->codecpar->codec_tag, format,
                                   size - (avio_tell(pb) - start_pos))) {
            sc->stsd_count++;
            continue;
        }

        sc->pseudo_stream_id = st->codecpar->codec_tag ? -1 : pseudo_stream_id;
        sc->dref_id= dref_id;
        sc->format = format;

        id = mov_codec_id(st, format);

        av_log(c->fc, AV_LOG_TRACE,
               "size=%"PRId64" 4CC=%s codec_type=%d\n", size,
               av_fourcc2str(format), st->codecpar->codec_type);

        if (st->codecpar->codec_type==AVMEDIA_TYPE_VIDEO) {
            st->codecpar->codec_id = id;
            mov_parse_stsd_video(c, pb, st, sc);
        } else if (st->codecpar->codec_type==AVMEDIA_TYPE_AUDIO) {
            st->codecpar->codec_id = id;
            mov_parse_stsd_audio(c, pb, st, sc);
            if (st->codecpar->sample_rate < 0) {
                av_log(c->fc, AV_LOG_ERROR, "Invalid sample rate %d\n", st->codecpar->sample_rate);
                return AVERROR_INVALIDDATA;
            }
        } else if (st->codecpar->codec_type==AVMEDIA_TYPE_SUBTITLE){
            st->codecpar->codec_id = id;
            mov_parse_stsd_subtitle(c, pb, st, sc,
                                    size - (avio_tell(pb) - start_pos));
        } else {
            ret = mov_parse_stsd_data(c, pb, st, sc,
                                      size - (avio_tell(pb) - start_pos));
            if (ret < 0)
                return ret;
        }
        /* this will read extra atoms at the end (wave, alac, damr, avcC, hvcC, SMI ...) */
        a.size = size - (avio_tell(pb) - start_pos);
        if (a.size > 8) {
            if ((ret = mov_read_default(c, pb, a)) < 0)
                return ret;
        } else if (a.size > 0)
            avio_skip(pb, a.size);

        if (sc->extradata && st->codecpar->extradata) {
            int extra_size = st->codecpar->extradata_size;

            /* Move the current stream extradata to the stream context one. */
            sc->extradata_size[pseudo_stream_id] = extra_size;
            sc->extradata[pseudo_stream_id] = av_malloc(extra_size + AV_INPUT_BUFFER_PADDING_SIZE);
            if (!sc->extradata[pseudo_stream_id])
                return AVERROR(ENOMEM);
            memcpy(sc->extradata[pseudo_stream_id], st->codecpar->extradata, extra_size);
            av_freep(&st->codecpar->extradata);
            st->codecpar->extradata_size = 0;
        }
        sc->stsd_count++;
    }

    if (pb->eof_reached) {
        av_log(c->fc, AV_LOG_WARNING, "reached eof, corrupted STSD atom\n");
        return AVERROR_EOF;
    }

    return 0;
}

static int mov_read_stsd(MOVContext *c, AVIOContext *pb, MOVAtom atom)
{
    AVStream *st;
    MOVStreamContext *sc;
    int ret, entries;

    if (c->fc->nb_streams < 1)
        return 0;
    st = c->fc->streams[c->fc->nb_streams - 1];
    sc = st->priv_data;

    avio_r8(pb); /* version */
    avio_rb24(pb); /* flags */
    entries = avio_rb32(pb);

    /* Each entry contains a size (4 bytes) and format (4 bytes). */
    if (entries <= 0 || entries > atom.size / 8) {
        av_log(c->fc, AV_LOG_ERROR, "invalid STSD entries %d\n", entries);
        return AVERROR_INVALIDDATA;
    }

    if (sc->extradata) {
        av_log(c->fc, AV_LOG_ERROR,
               "Duplicate stsd found in this track.\n");
        return AVERROR_INVALIDDATA;
    }

    /* Prepare space for hosting multiple extradata. */
    sc->extradata = av_mallocz_array(entries, sizeof(*sc->extradata));
    if (!sc->extradata)
        return AVERROR(ENOMEM);

    sc->extradata_size = av_mallocz_array(entries, sizeof(*sc->extradata_size));
    if (!sc->extradata_size) {
        ret = AVERROR(ENOMEM);
        goto fail;
    }

    ret = ff_mov_read_stsd_entries(c, pb, entries);
    if (ret < 0)
        goto fail;

    /* Restore back the primary extradata. */
    av_freep(&st->codecpar->extradata);
    st->codecpar->extradata_size = sc->extradata_size[0];
    if (sc->extradata_size[0]) {
        st->codecpar->extradata = av_mallocz(sc->extradata_size[0] + AV_INPUT_BUFFER_PADDING_SIZE);
        if (!st->codecpar->extradata)
            return AVERROR(ENOMEM);
        memcpy(st->codecpar->extradata, sc->extradata[0], sc->extradata_size[0]);
    }

    return mov_finalize_stsd_codec(c, pb, st, sc);
fail:
    if (sc->extradata) {
        int j;
        for (j = 0; j < sc->stsd_count; j++)
            av_freep(&sc->extradata[j]);
    }

    av_freep(&sc->extradata);
    av_freep(&sc->extradata_size);
    return ret;
}

static int mov_read_stsc(MOVContext *c, AVIOContext *pb, MOVAtom atom)
{
    AVStream *st;
    MOVStreamContext *sc;
    unsigned int i, entries;

    if (c->fc->nb_streams < 1)
        return 0;
    st = c->fc->streams[c->fc->nb_streams-1];
    sc = st->priv_data;

    avio_r8(pb); /* version */
    avio_rb24(pb); /* flags */

    entries = avio_rb32(pb);
    if ((uint64_t)entries * 12 + 4 > atom.size)
        return AVERROR_INVALIDDATA;

    av_log(c->fc, AV_LOG_TRACE, "track[%u].stsc.entries = %u\n", c->fc->nb_streams - 1, entries);

    if (!entries)
        return 0;
    if (sc->stsc_data)
        av_log(c->fc, AV_LOG_WARNING, "Duplicated STSC atom\n");
    av_free(sc->stsc_data);
    sc->stsc_count = 0;
    sc->stsc_data = av_malloc_array(entries, sizeof(*sc->stsc_data));
    if (!sc->stsc_data)
        return AVERROR(ENOMEM);

    for (i = 0; i < entries && !pb->eof_reached; i++) {
        sc->stsc_data[i].first = avio_rb32(pb);
        sc->stsc_data[i].count = avio_rb32(pb);
        sc->stsc_data[i].id = avio_rb32(pb);
    }

    sc->stsc_count = i;
    for (i = sc->stsc_count - 1; i < UINT_MAX; i--) {
        int64_t first_min = i + 1;
        if ((i+1 < sc->stsc_count && sc->stsc_data[i].first >= sc->stsc_data[i+1].first) ||
            (i > 0 && sc->stsc_data[i].first <= sc->stsc_data[i-1].first) ||
            sc->stsc_data[i].first < first_min ||
            sc->stsc_data[i].count < 1 ||
            sc->stsc_data[i].id < 1) {
            av_log(c->fc, AV_LOG_WARNING, "STSC entry %d is invalid (first=%d count=%d id=%d)\n", i, sc->stsc_data[i].first, sc->stsc_data[i].count, sc->stsc_data[i].id);
            if (i+1 >= sc->stsc_count) {
                sc->stsc_data[i].first = FFMAX(sc->stsc_data[i].first, first_min);
                if (i > 0 && sc->stsc_data[i].first <= sc->stsc_data[i-1].first)
                    sc->stsc_data[i].first = FFMIN(sc->stsc_data[i-1].first + 1LL, INT_MAX);
                sc->stsc_data[i].count = FFMAX(sc->stsc_data[i].count, 1);
                sc->stsc_data[i].id    = FFMAX(sc->stsc_data[i].id, 1);
                continue;
            }
            av_assert0(sc->stsc_data[i+1].first >= 2);
            // We replace this entry by the next valid
            sc->stsc_data[i].first = sc->stsc_data[i+1].first - 1;
            sc->stsc_data[i].count = sc->stsc_data[i+1].count;
            sc->stsc_data[i].id    = sc->stsc_data[i+1].id;
        }
    }

    if (pb->eof_reached) {
        av_log(c->fc, AV_LOG_WARNING, "reached eof, corrupted STSC atom\n");
        return AVERROR_EOF;
    }

    return 0;
}

static inline int mov_stsc_index_valid(unsigned int index, unsigned int count)
{
    return index < count - 1;
}

/* Compute the samples value for the stsc entry at the given index. */
static inline int64_t mov_get_stsc_samples(MOVStreamContext *sc, unsigned int index)
{
    int chunk_count;

    if (mov_stsc_index_valid(index, sc->stsc_count))
        chunk_count = sc->stsc_data[index + 1].first - sc->stsc_data[index].first;
    else {
        // Validation for stsc / stco  happens earlier in mov_read_stsc + mov_read_trak.
        av_assert0(sc->stsc_data[index].first <= sc->chunk_count);
        chunk_count = sc->chunk_count - (sc->stsc_data[index].first - 1);
    }

    return sc->stsc_data[index].count * (int64_t)chunk_count;
}

static int mov_read_stps(MOVContext *c, AVIOContext *pb, MOVAtom atom)
{
    AVStream *st;
    MOVStreamContext *sc;
    unsigned i, entries;

    if (c->fc->nb_streams < 1)
        return 0;
    st = c->fc->streams[c->fc->nb_streams-1];
    sc = st->priv_data;

    avio_rb32(pb); // version + flags

    entries = avio_rb32(pb);
    if (sc->stps_data)
        av_log(c->fc, AV_LOG_WARNING, "Duplicated STPS atom\n");
    av_free(sc->stps_data);
    sc->stps_count = 0;
    sc->stps_data = av_malloc_array(entries, sizeof(*sc->stps_data));
    if (!sc->stps_data)
        return AVERROR(ENOMEM);

    for (i = 0; i < entries && !pb->eof_reached; i++) {
        sc->stps_data[i] = avio_rb32(pb);
    }

    sc->stps_count = i;

    if (pb->eof_reached) {
        av_log(c->fc, AV_LOG_WARNING, "reached eof, corrupted STPS atom\n");
        return AVERROR_EOF;
    }

    return 0;
}

static int mov_read_stss(MOVContext *c, AVIOContext *pb, MOVAtom atom)
{
    AVStream *st;
    MOVStreamContext *sc;
    unsigned int i, entries;

    if (c->fc->nb_streams < 1)
        return 0;
    st = c->fc->streams[c->fc->nb_streams-1];
    sc = st->priv_data;

    avio_r8(pb); /* version */
    avio_rb24(pb); /* flags */

    entries = avio_rb32(pb);

    av_log(c->fc, AV_LOG_TRACE, "keyframe_count = %u\n", entries);

    if (!entries)
    {
        sc->keyframe_absent = 1;
        if (!st->need_parsing && st->codecpar->codec_type == AVMEDIA_TYPE_VIDEO)
            st->need_parsing = AVSTREAM_PARSE_HEADERS;
        return 0;
    }
    if (sc->keyframes)
        av_log(c->fc, AV_LOG_WARNING, "Duplicated STSS atom\n");
    if (entries >= UINT_MAX / sizeof(int))
        return AVERROR_INVALIDDATA;
    av_freep(&sc->keyframes);
    sc->keyframe_count = 0;
    sc->keyframes = av_malloc_array(entries, sizeof(*sc->keyframes));
    if (!sc->keyframes)
        return AVERROR(ENOMEM);

    for (i = 0; i < entries && !pb->eof_reached; i++) {
        sc->keyframes[i] = avio_rb32(pb);
    }

    sc->keyframe_count = i;

    if (pb->eof_reached) {
        av_log(c->fc, AV_LOG_WARNING, "reached eof, corrupted STSS atom\n");
        return AVERROR_EOF;
    }

    return 0;
}

static int mov_read_stsz(MOVContext *c, AVIOContext *pb, MOVAtom atom)
{
    AVStream *st;
    MOVStreamContext *sc;
    unsigned int i, entries, sample_size, field_size, num_bytes;
    GetBitContext gb;
    unsigned char* buf;
    int ret;

    if (c->fc->nb_streams < 1)
        return 0;
    st = c->fc->streams[c->fc->nb_streams-1];
    sc = st->priv_data;

    avio_r8(pb); /* version */
    avio_rb24(pb); /* flags */

    if (atom.type == MKTAG('s','t','s','z')) {
        sample_size = avio_rb32(pb);
        if (!sc->sample_size) /* do not overwrite value computed in stsd */
            sc->sample_size = sample_size;
        sc->stsz_sample_size = sample_size;
        field_size = 32;
    } else {
        sample_size = 0;
        avio_rb24(pb); /* reserved */
        field_size = avio_r8(pb);
    }
    entries = avio_rb32(pb);

    av_log(c->fc, AV_LOG_TRACE, "sample_size = %u sample_count = %u\n", sc->sample_size, entries);

    sc->sample_count = entries;
    if (sample_size)
        return 0;

    if (field_size != 4 && field_size != 8 && field_size != 16 && field_size != 32) {
        av_log(c->fc, AV_LOG_ERROR, "Invalid sample field size %u\n", field_size);
        return AVERROR_INVALIDDATA;
    }

    if (!entries)
        return 0;
    if (entries >= (UINT_MAX - 4) / field_size)
        return AVERROR_INVALIDDATA;
    if (sc->sample_sizes)
        av_log(c->fc, AV_LOG_WARNING, "Duplicated STSZ atom\n");
    av_free(sc->sample_sizes);
    sc->sample_count = 0;
    sc->sample_sizes = av_malloc_array(entries, sizeof(*sc->sample_sizes));
    if (!sc->sample_sizes)
        return AVERROR(ENOMEM);

    num_bytes = (entries*field_size+4)>>3;

    buf = av_malloc(num_bytes+AV_INPUT_BUFFER_PADDING_SIZE);
    if (!buf) {
        av_freep(&sc->sample_sizes);
        return AVERROR(ENOMEM);
    }

    ret = ffio_read_size(pb, buf, num_bytes);
    if (ret < 0) {
        av_freep(&sc->sample_sizes);
        av_free(buf);
        return ret;
    }

    init_get_bits(&gb, buf, 8*num_bytes);

    for (i = 0; i < entries && !pb->eof_reached; i++) {
        sc->sample_sizes[i] = get_bits_long(&gb, field_size);
        sc->data_size += sc->sample_sizes[i];
    }

    sc->sample_count = i;

    av_free(buf);

    if (pb->eof_reached) {
        av_log(c->fc, AV_LOG_WARNING, "reached eof, corrupted STSZ atom\n");
        return AVERROR_EOF;
    }

    return 0;
}

static int mov_read_stts(MOVContext *c, AVIOContext *pb, MOVAtom atom)
{
    AVStream *st;
    MOVStreamContext *sc;
    unsigned int i, entries, alloc_size = 0;
    int64_t duration=0;
    int64_t total_sample_count=0;

    if (c->fc->nb_streams < 1)
        return 0;
    st = c->fc->streams[c->fc->nb_streams-1];
    sc = st->priv_data;

    avio_r8(pb); /* version */
    avio_rb24(pb); /* flags */
    entries = avio_rb32(pb);

    av_log(c->fc, AV_LOG_TRACE, "track[%u].stts.entries = %u\n",
            c->fc->nb_streams-1, entries);

    if (sc->stts_data)
        av_log(c->fc, AV_LOG_WARNING, "Duplicated STTS atom\n");
    av_freep(&sc->stts_data);
    sc->stts_count = 0;
    if (entries >= INT_MAX / sizeof(*sc->stts_data))
        return AVERROR(ENOMEM);

    for (i = 0; i < entries && !pb->eof_reached; i++) {
        int sample_duration;
        unsigned int sample_count;
        unsigned int min_entries = FFMIN(FFMAX(i + 1, 1024 * 1024), entries);
        MOVStts *stts_data = av_fast_realloc(sc->stts_data, &alloc_size,
                                             min_entries * sizeof(*sc->stts_data));
        if (!stts_data) {
            av_freep(&sc->stts_data);
            sc->stts_count = 0;
            return AVERROR(ENOMEM);
        }
        sc->stts_count = min_entries;
        sc->stts_data = stts_data;

        sample_count=avio_rb32(pb);
        sample_duration = avio_rb32(pb);

        sc->stts_data[i].count= sample_count;
        sc->stts_data[i].duration= sample_duration;

        av_log(c->fc, AV_LOG_TRACE, "sample_count=%d, sample_duration=%d\n",
                sample_count, sample_duration);

        if (   i+1 == entries
            && i
            && sample_count == 1
            && total_sample_count > 100
            && sample_duration/10 > duration / total_sample_count)
            sample_duration = duration / total_sample_count;
        duration+=(int64_t)sample_duration*(uint64_t)sample_count;
        total_sample_count+=sample_count;
    }

    sc->stts_count = i;

    if (duration > 0 &&
        duration <= INT64_MAX - sc->duration_for_fps &&
        total_sample_count <= INT64_MAX - sc->nb_frames_for_fps
    ) {
        sc->duration_for_fps  += duration;
        sc->nb_frames_for_fps += total_sample_count;
    }

    if (pb->eof_reached) {
        av_log(c->fc, AV_LOG_WARNING, "reached eof, corrupted STTS atom\n");
        return AVERROR_EOF;
    }

    st->nb_frames= total_sample_count;
    if (duration)
        st->duration= duration;
    sc->track_end = duration;
    return 0;
}

static void mov_update_dts_shift(MOVStreamContext *sc, int duration)
{
    if (duration < 0) {
        if (duration == INT_MIN) {
            av_log(NULL, AV_LOG_WARNING, "mov_update_dts_shift(): dts_shift set to %d\n", INT_MAX);
            duration++;
        }
        sc->dts_shift = FFMAX(sc->dts_shift, -duration);
    }
}

static int mov_read_ctts(MOVContext *c, AVIOContext *pb, MOVAtom atom)
{
    AVStream *st;
    MOVStreamContext *sc;
    unsigned int i, entries, ctts_count = 0;

    if (c->fc->nb_streams < 1)
        return 0;
    st = c->fc->streams[c->fc->nb_streams-1];
    sc = st->priv_data;

    avio_r8(pb); /* version */
    avio_rb24(pb); /* flags */
    entries = avio_rb32(pb);

    av_log(c->fc, AV_LOG_TRACE, "track[%u].ctts.entries = %u\n", c->fc->nb_streams - 1, entries);

    if (!entries)
        return 0;
    if (entries >= UINT_MAX / sizeof(*sc->ctts_data))
        return AVERROR_INVALIDDATA;
    av_freep(&sc->ctts_data);
    sc->ctts_data = av_fast_realloc(NULL, &sc->ctts_allocated_size, entries * sizeof(*sc->ctts_data));
    if (!sc->ctts_data)
        return AVERROR(ENOMEM);

    for (i = 0; i < entries && !pb->eof_reached; i++) {
        int count    =avio_rb32(pb);
        int duration =avio_rb32(pb);

        if (count <= 0) {
            av_log(c->fc, AV_LOG_TRACE,
                   "ignoring CTTS entry with count=%d duration=%d\n",
                   count, duration);
            continue;
        }

        add_ctts_entry(&sc->ctts_data, &ctts_count, &sc->ctts_allocated_size,
                       count, duration);

        av_log(c->fc, AV_LOG_TRACE, "count=%d, duration=%d\n",
                count, duration);

        if (FFNABS(duration) < -(1<<28) && i+2<entries) {
            av_log(c->fc, AV_LOG_WARNING, "CTTS invalid\n");
            av_freep(&sc->ctts_data);
            sc->ctts_count = 0;
            return 0;
        }

        if (i+2<entries)
            mov_update_dts_shift(sc, duration);
    }

    sc->ctts_count = ctts_count;

    if (pb->eof_reached) {
        av_log(c->fc, AV_LOG_WARNING, "reached eof, corrupted CTTS atom\n");
        return AVERROR_EOF;
    }

    av_log(c->fc, AV_LOG_TRACE, "dts shift %d\n", sc->dts_shift);

    return 0;
}

static int mov_read_sbgp(MOVContext *c, AVIOContext *pb, MOVAtom atom)
{
    AVStream *st;
    MOVStreamContext *sc;
    unsigned int i, entries;
    uint8_t version;
    uint32_t grouping_type;

    if (c->fc->nb_streams < 1)
        return 0;
    st = c->fc->streams[c->fc->nb_streams-1];
    sc = st->priv_data;

    version = avio_r8(pb); /* version */
    avio_rb24(pb); /* flags */
    grouping_type = avio_rl32(pb);
    if (grouping_type != MKTAG( 'r','a','p',' '))
        return 0; /* only support 'rap ' grouping */
    if (version == 1)
        avio_rb32(pb); /* grouping_type_parameter */

    entries = avio_rb32(pb);
    if (!entries)
        return 0;
    if (sc->rap_group)
        av_log(c->fc, AV_LOG_WARNING, "Duplicated SBGP atom\n");
    av_free(sc->rap_group);
    sc->rap_group_count = 0;
    sc->rap_group = av_malloc_array(entries, sizeof(*sc->rap_group));
    if (!sc->rap_group)
        return AVERROR(ENOMEM);

    for (i = 0; i < entries && !pb->eof_reached; i++) {
        sc->rap_group[i].count = avio_rb32(pb); /* sample_count */
        sc->rap_group[i].index = avio_rb32(pb); /* group_description_index */
    }

    sc->rap_group_count = i;

    if (pb->eof_reached) {
        av_log(c->fc, AV_LOG_WARNING, "reached eof, corrupted SBGP atom\n");
        return AVERROR_EOF;
    }

    return 0;
}

/**
 * Get ith edit list entry (media time, duration).
 */
static int get_edit_list_entry(MOVContext *mov,
                               const MOVStreamContext *msc,
                               unsigned int edit_list_index,
                               int64_t *edit_list_media_time,
                               int64_t *edit_list_duration,
                               int64_t global_timescale)
{
    if (edit_list_index == msc->elst_count) {
        return 0;
    }
    *edit_list_media_time = msc->elst_data[edit_list_index].time;
    *edit_list_duration = msc->elst_data[edit_list_index].duration;

    /* duration is in global timescale units;convert to msc timescale */
    if (global_timescale == 0) {
      avpriv_request_sample(mov->fc, "Support for mvhd.timescale = 0 with editlists");
      return 0;
    }
    *edit_list_duration = av_rescale(*edit_list_duration, msc->time_scale,
                                     global_timescale);
    return 1;
}

/**
 * Find the closest previous frame to the timestamp_pts, in e_old index
 * entries. Searching for just any frame / just key frames can be controlled by
 * last argument 'flag'.
 * Note that if ctts_data is not NULL, we will always search for a key frame
 * irrespective of the value of 'flag'. If we don't find any keyframe, we will
 * return the first frame of the video.
 *
 * Here the timestamp_pts is considered to be a presentation timestamp and
 * the timestamp of index entries are considered to be decoding timestamps.
 *
 * Returns 0 if successful in finding a frame, else returns -1.
 * Places the found index corresponding output arg.
 *
 * If ctts_old is not NULL, then refines the searched entry by searching
 * backwards from the found timestamp, to find the frame with correct PTS.
 *
 * Places the found ctts_index and ctts_sample in corresponding output args.
 */
static int find_prev_closest_index(AVStream *st,
                                   AVIndexEntry *e_old,
                                   int nb_old,
                                   MOVStts* ctts_data,
                                   int64_t ctts_count,
                                   int64_t timestamp_pts,
                                   int flag,
                                   int64_t* index,
                                   int64_t* ctts_index,
                                   int64_t* ctts_sample)
{
    MOVStreamContext *msc = st->priv_data;
    AVIndexEntry *e_keep = st->index_entries;
    int nb_keep = st->nb_index_entries;
    int64_t i = 0;
    int64_t index_ctts_count;

    av_assert0(index);

    // If dts_shift > 0, then all the index timestamps will have to be offset by
    // at least dts_shift amount to obtain PTS.
    // Hence we decrement the searched timestamp_pts by dts_shift to find the closest index element.
    if (msc->dts_shift > 0) {
        timestamp_pts -= msc->dts_shift;
    }

    st->index_entries = e_old;
    st->nb_index_entries = nb_old;
    *index = av_index_search_timestamp(st, timestamp_pts, flag | AVSEEK_FLAG_BACKWARD);

    // Keep going backwards in the index entries until the timestamp is the same.
    if (*index >= 0) {
        for (i = *index; i > 0 && e_old[i].timestamp == e_old[i - 1].timestamp;
             i--) {
            if ((flag & AVSEEK_FLAG_ANY) ||
                (e_old[i - 1].flags & AVINDEX_KEYFRAME)) {
                *index = i - 1;
            }
        }
    }

    // If we have CTTS then refine the search, by searching backwards over PTS
    // computed by adding corresponding CTTS durations to index timestamps.
    if (ctts_data && *index >= 0) {
        av_assert0(ctts_index);
        av_assert0(ctts_sample);
        // Find out the ctts_index for the found frame.
        *ctts_index = 0;
        *ctts_sample = 0;
        for (index_ctts_count = 0; index_ctts_count < *index; index_ctts_count++) {
            if (*ctts_index < ctts_count) {
                (*ctts_sample)++;
                if (ctts_data[*ctts_index].count == *ctts_sample) {
                    (*ctts_index)++;
                    *ctts_sample = 0;
                }
            }
        }

        while (*index >= 0 && (*ctts_index) >= 0 && (*ctts_index) < ctts_count) {
            // Find a "key frame" with PTS <= timestamp_pts (So that we can decode B-frames correctly).
            // No need to add dts_shift to the timestamp here becase timestamp_pts has already been
            // compensated by dts_shift above.
            if ((e_old[*index].timestamp + ctts_data[*ctts_index].duration) <= timestamp_pts &&
                (e_old[*index].flags & AVINDEX_KEYFRAME)) {
                break;
            }

            (*index)--;
            if (*ctts_sample == 0) {
                (*ctts_index)--;
                if (*ctts_index >= 0)
                  *ctts_sample = ctts_data[*ctts_index].count - 1;
            } else {
                (*ctts_sample)--;
            }
        }
    }

    /* restore AVStream state*/
    st->index_entries = e_keep;
    st->nb_index_entries = nb_keep;
    return *index >= 0 ? 0 : -1;
}

/**
 * Add index entry with the given values, to the end of st->index_entries.
 * Returns the new size st->index_entries if successful, else returns -1.
 *
 * This function is similar to ff_add_index_entry in libavformat/utils.c
 * except that here we are always unconditionally adding an index entry to
 * the end, instead of searching the entries list and skipping the add if
 * there is an existing entry with the same timestamp.
 * This is needed because the mov_fix_index calls this func with the same
 * unincremented timestamp for successive discarded frames.
 */
static int64_t add_index_entry(AVStream *st, int64_t pos, int64_t timestamp,
                               int size, int distance, int flags)
{
    AVIndexEntry *entries, *ie;
    int64_t index = -1;
    const size_t min_size_needed = (st->nb_index_entries + 1) * sizeof(AVIndexEntry);

    // Double the allocation each time, to lower memory fragmentation.
    // Another difference from ff_add_index_entry function.
    const size_t requested_size =
        min_size_needed > st->index_entries_allocated_size ?
        FFMAX(min_size_needed, 2 * st->index_entries_allocated_size) :
        min_size_needed;

    if((unsigned)st->nb_index_entries + 1 >= UINT_MAX / sizeof(AVIndexEntry))
        return -1;

    entries = av_fast_realloc(st->index_entries,
                              &st->index_entries_allocated_size,
                              requested_size);
    if(!entries)
        return -1;

    st->index_entries= entries;

    index= st->nb_index_entries++;
    ie= &entries[index];

    ie->pos = pos;
    ie->timestamp = timestamp;
    ie->min_distance= distance;
    ie->size= size;
    ie->flags = flags;
    return index;
}

/**
 * Rewrite timestamps of index entries in the range [end_index - frame_duration_buffer_size, end_index)
 * by subtracting end_ts successively by the amounts given in frame_duration_buffer.
 */
static void fix_index_entry_timestamps(AVStream* st, int end_index, int64_t end_ts,
                                       int64_t* frame_duration_buffer,
                                       int frame_duration_buffer_size) {
    int i = 0;
    av_assert0(end_index >= 0 && end_index <= st->nb_index_entries);
    for (i = 0; i < frame_duration_buffer_size; i++) {
        end_ts -= frame_duration_buffer[frame_duration_buffer_size - 1 - i];
        st->index_entries[end_index - 1 - i].timestamp = end_ts;
    }
}

/**
 * Append a new ctts entry to ctts_data.
 * Returns the new ctts_count if successful, else returns -1.
 */
static int64_t add_ctts_entry(MOVStts** ctts_data, unsigned int* ctts_count, unsigned int* allocated_size,
                              int count, int duration)
{
    MOVStts *ctts_buf_new;
    const size_t min_size_needed = (*ctts_count + 1) * sizeof(MOVStts);
    const size_t requested_size =
        min_size_needed > *allocated_size ?
        FFMAX(min_size_needed, 2 * (*allocated_size)) :
        min_size_needed;

    if((unsigned)(*ctts_count) >= UINT_MAX / sizeof(MOVStts) - 1)
        return -1;

    ctts_buf_new = av_fast_realloc(*ctts_data, allocated_size, requested_size);

    if(!ctts_buf_new)
        return -1;

    *ctts_data = ctts_buf_new;

    ctts_buf_new[*ctts_count].count = count;
    ctts_buf_new[*ctts_count].duration = duration;

    *ctts_count = (*ctts_count) + 1;
    return *ctts_count;
}

#define MAX_REORDER_DELAY 16
static void mov_estimate_video_delay(MOVContext *c, AVStream* st) {
    MOVStreamContext *msc = st->priv_data;
    int ind;
    int ctts_ind = 0;
    int ctts_sample = 0;
    int64_t pts_buf[MAX_REORDER_DELAY + 1]; // Circular buffer to sort pts.
    int buf_start = 0;
    int j, r, num_swaps;

    for (j = 0; j < MAX_REORDER_DELAY + 1; j++)
        pts_buf[j] = INT64_MIN;

    if (st->codecpar->video_delay <= 0 && msc->ctts_data &&
        st->codecpar->codec_id == AV_CODEC_ID_H264) {
        st->codecpar->video_delay = 0;
        for(ind = 0; ind < st->nb_index_entries && ctts_ind < msc->ctts_count; ++ind) {
            // Point j to the last elem of the buffer and insert the current pts there.
            j = buf_start;
            buf_start = (buf_start + 1);
            if (buf_start == MAX_REORDER_DELAY + 1)
                buf_start = 0;

            pts_buf[j] = st->index_entries[ind].timestamp + msc->ctts_data[ctts_ind].duration;

            // The timestamps that are already in the sorted buffer, and are greater than the
            // current pts, are exactly the timestamps that need to be buffered to output PTS
            // in correct sorted order.
            // Hence the video delay (which is the buffer size used to sort DTS and output PTS),
            // can be computed as the maximum no. of swaps any particular timestamp needs to
            // go through, to keep this buffer in sorted order.
            num_swaps = 0;
            while (j != buf_start) {
                r = j - 1;
                if (r < 0) r = MAX_REORDER_DELAY;
                if (pts_buf[j] < pts_buf[r]) {
                    FFSWAP(int64_t, pts_buf[j], pts_buf[r]);
                    ++num_swaps;
                } else {
                    break;
                }
                j = r;
            }
            st->codecpar->video_delay = FFMAX(st->codecpar->video_delay, num_swaps);

            ctts_sample++;
            if (ctts_sample == msc->ctts_data[ctts_ind].count) {
                ctts_ind++;
                ctts_sample = 0;
            }
        }
        av_log(c->fc, AV_LOG_DEBUG, "Setting codecpar->delay to %d for stream st: %d\n",
               st->codecpar->video_delay, st->index);
    }
}

static void mov_current_sample_inc(MOVStreamContext *sc)
{
    sc->current_sample++;
    sc->current_index++;
    if (sc->index_ranges &&
        sc->current_index >= sc->current_index_range->end &&
        sc->current_index_range->end) {
        sc->current_index_range++;
        sc->current_index = sc->current_index_range->start;
    }
}

static void mov_current_sample_dec(MOVStreamContext *sc)
{
    sc->current_sample--;
    sc->current_index--;
    if (sc->index_ranges &&
        sc->current_index < sc->current_index_range->start &&
        sc->current_index_range > sc->index_ranges) {
        sc->current_index_range--;
        sc->current_index = sc->current_index_range->end - 1;
    }
}

static void mov_current_sample_set(MOVStreamContext *sc, int current_sample)
{
    int64_t range_size;

    sc->current_sample = current_sample;
    sc->current_index = current_sample;
    if (!sc->index_ranges) {
        return;
    }

    for (sc->current_index_range = sc->index_ranges;
        sc->current_index_range->end;
        sc->current_index_range++) {
        range_size = sc->current_index_range->end - sc->current_index_range->start;
        if (range_size > current_sample) {
            sc->current_index = sc->current_index_range->start + current_sample;
            break;
        }
        current_sample -= range_size;
    }
}

/**
 * Fix st->index_entries, so that it contains only the entries (and the entries
 * which are needed to decode them) that fall in the edit list time ranges.
 * Also fixes the timestamps of the index entries to match the timeline
 * specified the edit lists.
 */
static void mov_fix_index(MOVContext *mov, AVStream *st)
{
    MOVStreamContext *msc = st->priv_data;
    AVIndexEntry *e_old = st->index_entries;
    int nb_old = st->nb_index_entries;
    const AVIndexEntry *e_old_end = e_old + nb_old;
    const AVIndexEntry *current = NULL;
    MOVStts *ctts_data_old = msc->ctts_data;
    int64_t ctts_index_old = 0;
    int64_t ctts_sample_old = 0;
    int64_t ctts_count_old = msc->ctts_count;
    int64_t edit_list_media_time = 0;
    int64_t edit_list_duration = 0;
    int64_t frame_duration = 0;
    int64_t edit_list_dts_counter = 0;
    int64_t edit_list_dts_entry_end = 0;
    int64_t edit_list_start_ctts_sample = 0;
    int64_t curr_cts;
    int64_t curr_ctts = 0;
    int64_t empty_edits_sum_duration = 0;
    int64_t edit_list_index = 0;
    int64_t index;
    int flags;
    int64_t start_dts = 0;
    int64_t edit_list_start_encountered = 0;
    int64_t search_timestamp = 0;
    int64_t* frame_duration_buffer = NULL;
    int num_discarded_begin = 0;
    int first_non_zero_audio_edit = -1;
    int packet_skip_samples = 0;
    MOVIndexRange *current_index_range;
    int i;
    int found_keyframe_after_edit = 0;

    if (!msc->elst_data || msc->elst_count <= 0 || nb_old <= 0) {
        return;
    }

    // allocate the index ranges array
    msc->index_ranges = av_malloc((msc->elst_count + 1) * sizeof(msc->index_ranges[0]));
    if (!msc->index_ranges) {
        av_log(mov->fc, AV_LOG_ERROR, "Cannot allocate index ranges buffer\n");
        return;
    }
    msc->current_index_range = msc->index_ranges;
    current_index_range = msc->index_ranges - 1;

    // Clean AVStream from traces of old index
    st->index_entries = NULL;
    st->index_entries_allocated_size = 0;
    st->nb_index_entries = 0;

    // Clean ctts fields of MOVStreamContext
    msc->ctts_data = NULL;
    msc->ctts_count = 0;
    msc->ctts_index = 0;
    msc->ctts_sample = 0;
    msc->ctts_allocated_size = 0;

    // Reinitialize min_corrected_pts so that it can be computed again.
    msc->min_corrected_pts = -1;

    // If the dts_shift is positive (in case of negative ctts values in mov),
    // then negate the DTS by dts_shift
    if (msc->dts_shift > 0) {
        edit_list_dts_entry_end -= msc->dts_shift;
        av_log(mov->fc, AV_LOG_DEBUG, "Shifting DTS by %d because of negative CTTS.\n", msc->dts_shift);
    }

    start_dts = edit_list_dts_entry_end;

    while (get_edit_list_entry(mov, msc, edit_list_index, &edit_list_media_time,
                               &edit_list_duration, mov->time_scale)) {
        av_log(mov->fc, AV_LOG_DEBUG, "Processing st: %d, edit list %"PRId64" - media time: %"PRId64", duration: %"PRId64"\n",
               st->index, edit_list_index, edit_list_media_time, edit_list_duration);
        edit_list_index++;
        edit_list_dts_counter = edit_list_dts_entry_end;
        edit_list_dts_entry_end += edit_list_duration;
        num_discarded_begin = 0;
        if (edit_list_media_time == -1) {
            empty_edits_sum_duration += edit_list_duration;
            continue;
        }

        // If we encounter a non-negative edit list reset the skip_samples/start_pad fields and set them
        // according to the edit list below.
        if (st->codecpar->codec_type == AVMEDIA_TYPE_AUDIO) {
            if (first_non_zero_audio_edit < 0) {
                first_non_zero_audio_edit = 1;
            } else {
                first_non_zero_audio_edit = 0;
            }

            if (first_non_zero_audio_edit > 0)
                st->skip_samples = msc->start_pad = 0;
        }

        // While reordering frame index according to edit list we must handle properly
        // the scenario when edit list entry starts from none key frame.
        // We find closest previous key frame and preserve it and consequent frames in index.
        // All frames which are outside edit list entry time boundaries will be dropped after decoding.
        search_timestamp = edit_list_media_time;
        if (st->codecpar->codec_type == AVMEDIA_TYPE_AUDIO) {
            // Audio decoders like AAC need need a decoder delay samples previous to the current sample,
            // to correctly decode this frame. Hence for audio we seek to a frame 1 sec. before the
            // edit_list_media_time to cover the decoder delay.
            search_timestamp = FFMAX(search_timestamp - msc->time_scale, e_old[0].timestamp);
        }

        if (find_prev_closest_index(st, e_old, nb_old, ctts_data_old, ctts_count_old, search_timestamp, 0,
                                    &index, &ctts_index_old, &ctts_sample_old) < 0) {
            av_log(mov->fc, AV_LOG_WARNING,
                   "st: %d edit list: %"PRId64" Missing key frame while searching for timestamp: %"PRId64"\n",
                   st->index, edit_list_index, search_timestamp);
            if (find_prev_closest_index(st, e_old, nb_old, ctts_data_old, ctts_count_old, search_timestamp, AVSEEK_FLAG_ANY,
                                        &index, &ctts_index_old, &ctts_sample_old) < 0) {
                av_log(mov->fc, AV_LOG_WARNING,
                       "st: %d edit list %"PRId64" Cannot find an index entry before timestamp: %"PRId64".\n",
                       st->index, edit_list_index, search_timestamp);
                index = 0;
                ctts_index_old = 0;
                ctts_sample_old = 0;
            }
        }
        current = e_old + index;
        edit_list_start_ctts_sample = ctts_sample_old;

        // Iterate over index and arrange it according to edit list
        edit_list_start_encountered = 0;
        found_keyframe_after_edit = 0;
        for (; current < e_old_end; current++, index++) {
            // check  if frame outside edit list mark it for discard
            frame_duration = (current + 1 <  e_old_end) ?
                             ((current + 1)->timestamp - current->timestamp) : edit_list_duration;

            flags = current->flags;

            // frames (pts) before or after edit list
            curr_cts = current->timestamp + msc->dts_shift;
            curr_ctts = 0;

            if (ctts_data_old && ctts_index_old < ctts_count_old) {
                curr_ctts = ctts_data_old[ctts_index_old].duration;
                av_log(mov->fc, AV_LOG_DEBUG, "stts: %"PRId64" ctts: %"PRId64", ctts_index: %"PRId64", ctts_count: %"PRId64"\n",
                       curr_cts, curr_ctts, ctts_index_old, ctts_count_old);
                curr_cts += curr_ctts;
                ctts_sample_old++;
                if (ctts_sample_old == ctts_data_old[ctts_index_old].count) {
                    if (add_ctts_entry(&msc->ctts_data, &msc->ctts_count,
                                       &msc->ctts_allocated_size,
                                       ctts_data_old[ctts_index_old].count - edit_list_start_ctts_sample,
                                       ctts_data_old[ctts_index_old].duration) == -1) {
                        av_log(mov->fc, AV_LOG_ERROR, "Cannot add CTTS entry %"PRId64" - {%"PRId64", %d}\n",
                               ctts_index_old,
                               ctts_data_old[ctts_index_old].count - edit_list_start_ctts_sample,
                               ctts_data_old[ctts_index_old].duration);
                        break;
                    }
                    ctts_index_old++;
                    ctts_sample_old = 0;
                    edit_list_start_ctts_sample = 0;
                }
            }

            if (curr_cts < edit_list_media_time || curr_cts >= (edit_list_duration + edit_list_media_time)) {
                if (st->codecpar->codec_type == AVMEDIA_TYPE_AUDIO && st->codecpar->codec_id != AV_CODEC_ID_VORBIS &&
                    curr_cts < edit_list_media_time && curr_cts + frame_duration > edit_list_media_time &&
                    first_non_zero_audio_edit > 0) {
                    packet_skip_samples = edit_list_media_time - curr_cts;
                    st->skip_samples += packet_skip_samples;

                    // Shift the index entry timestamp by packet_skip_samples to be correct.
                    edit_list_dts_counter -= packet_skip_samples;
                    if (edit_list_start_encountered == 0)  {
                        edit_list_start_encountered = 1;
                        // Make timestamps strictly monotonically increasing for audio, by rewriting timestamps for
                        // discarded packets.
                        if (frame_duration_buffer) {
                            fix_index_entry_timestamps(st, st->nb_index_entries, edit_list_dts_counter,
                                                       frame_duration_buffer, num_discarded_begin);
                            av_freep(&frame_duration_buffer);
                        }
                    }

                    av_log(mov->fc, AV_LOG_DEBUG, "skip %d audio samples from curr_cts: %"PRId64"\n", packet_skip_samples, curr_cts);
                } else {
                    flags |= AVINDEX_DISCARD_FRAME;
                    av_log(mov->fc, AV_LOG_DEBUG, "drop a frame at curr_cts: %"PRId64" @ %"PRId64"\n", curr_cts, index);

                    if (st->codecpar->codec_type == AVMEDIA_TYPE_AUDIO && edit_list_start_encountered == 0) {
                        num_discarded_begin++;
                        frame_duration_buffer = av_realloc(frame_duration_buffer,
                                                           num_discarded_begin * sizeof(int64_t));
                        if (!frame_duration_buffer) {
                            av_log(mov->fc, AV_LOG_ERROR, "Cannot reallocate frame duration buffer\n");
                            break;
                        }
                        frame_duration_buffer[num_discarded_begin - 1] = frame_duration;

                        // Increment skip_samples for the first non-zero audio edit list
                        if (first_non_zero_audio_edit > 0 && st->codecpar->codec_id != AV_CODEC_ID_VORBIS) {
                            st->skip_samples += frame_duration;
                        }
                    }
                }
            } else {
                if (msc->min_corrected_pts < 0) {
                    msc->min_corrected_pts = edit_list_dts_counter + curr_ctts + msc->dts_shift;
                } else {
                    msc->min_corrected_pts = FFMIN(msc->min_corrected_pts, edit_list_dts_counter + curr_ctts + msc->dts_shift);
                }
                if (edit_list_start_encountered == 0) {
                    edit_list_start_encountered = 1;
                    // Make timestamps strictly monotonically increasing for audio, by rewriting timestamps for
                    // discarded packets.
                    if (st->codecpar->codec_type == AVMEDIA_TYPE_AUDIO && frame_duration_buffer) {
                        fix_index_entry_timestamps(st, st->nb_index_entries, edit_list_dts_counter,
                                                   frame_duration_buffer, num_discarded_begin);
                        av_freep(&frame_duration_buffer);
                    }
                }
            }

            if (add_index_entry(st, current->pos, edit_list_dts_counter, current->size,
                                current->min_distance, flags) == -1) {
                av_log(mov->fc, AV_LOG_ERROR, "Cannot add index entry\n");
                break;
            }

            // Update the index ranges array
            if (current_index_range < msc->index_ranges || index != current_index_range->end) {
                current_index_range++;
                current_index_range->start = index;
            }
            current_index_range->end = index + 1;

            // Only start incrementing DTS in frame_duration amounts, when we encounter a frame in edit list.
            if (edit_list_start_encountered > 0) {
                edit_list_dts_counter = edit_list_dts_counter + frame_duration;
            }

            // Break when found first key frame after edit entry completion
            if ((curr_cts + frame_duration >= (edit_list_duration + edit_list_media_time)) &&
                ((flags & AVINDEX_KEYFRAME) || ((st->codecpar->codec_type == AVMEDIA_TYPE_AUDIO)))) {
                if (ctts_data_old) {
                    // If we have CTTS and this is the first keyframe after edit elist,
                    // wait for one more, because there might be trailing B-frames after this I-frame
                    // that do belong to the edit.
                    if (st->codecpar->codec_type != AVMEDIA_TYPE_AUDIO && found_keyframe_after_edit == 0) {
                        found_keyframe_after_edit = 1;
                        continue;
                    }
                    if (ctts_sample_old != 0) {
                        if (add_ctts_entry(&msc->ctts_data, &msc->ctts_count,
                                           &msc->ctts_allocated_size,
                                           ctts_sample_old - edit_list_start_ctts_sample,
                                           ctts_data_old[ctts_index_old].duration) == -1) {
                            av_log(mov->fc, AV_LOG_ERROR, "Cannot add CTTS entry %"PRId64" - {%"PRId64", %d}\n",
                                   ctts_index_old, ctts_sample_old - edit_list_start_ctts_sample,
                                   ctts_data_old[ctts_index_old].duration);
                            break;
                        }
                    }
                }
                break;
            }
        }
    }
    // If there are empty edits, then msc->min_corrected_pts might be positive
    // intentionally. So we subtract the sum duration of emtpy edits here.
    msc->min_corrected_pts -= empty_edits_sum_duration;

    // If the minimum pts turns out to be greater than zero after fixing the index, then we subtract the
    // dts by that amount to make the first pts zero.
    if (st->codecpar->codec_type == AVMEDIA_TYPE_VIDEO && msc->min_corrected_pts > 0) {
        av_log(mov->fc, AV_LOG_DEBUG, "Offset DTS by %"PRId64" to make first pts zero.\n", msc->min_corrected_pts);
        for (i = 0; i < st->nb_index_entries; ++i) {
            st->index_entries[i].timestamp -= msc->min_corrected_pts;
        }
    }

    // Update av stream length
    st->duration = edit_list_dts_entry_end - start_dts;
    msc->start_pad = st->skip_samples;

    // Free the old index and the old CTTS structures
    av_free(e_old);
    av_free(ctts_data_old);
    av_freep(&frame_duration_buffer);

    // Null terminate the index ranges array
    current_index_range++;
    current_index_range->start = 0;
    current_index_range->end = 0;
    msc->current_index = msc->index_ranges[0].start;
}

static void mov_build_index(MOVContext *mov, AVStream *st)
{
    MOVStreamContext *sc = st->priv_data;
    int64_t current_offset;
    int64_t current_dts = 0;
    unsigned int stts_index = 0;
    unsigned int stsc_index = 0;
    unsigned int stss_index = 0;
    unsigned int stps_index = 0;
    unsigned int i, j;
    uint64_t stream_size = 0;
    MOVStts *ctts_data_old = sc->ctts_data;
    unsigned int ctts_count_old = sc->ctts_count;

    if (sc->elst_count) {
        int i, edit_start_index = 0, multiple_edits = 0;
        int64_t empty_duration = 0; // empty duration of the first edit list entry
        int64_t start_time = 0; // start time of the media

        for (i = 0; i < sc->elst_count; i++) {
            const MOVElst *e = &sc->elst_data[i];
            if (i == 0 && e->time == -1) {
                /* if empty, the first entry is the start time of the stream
                 * relative to the presentation itself */
                empty_duration = e->duration;
                edit_start_index = 1;
            } else if (i == edit_start_index && e->time >= 0) {
                start_time = e->time;
            } else {
                multiple_edits = 1;
            }
        }

        if (multiple_edits && !mov->advanced_editlist)
            av_log(mov->fc, AV_LOG_WARNING, "multiple edit list entries, "
                   "Use -advanced_editlist to correctly decode otherwise "
                   "a/v desync might occur\n");

        /* adjust first dts according to edit list */
        if ((empty_duration || start_time) && mov->time_scale > 0) {
            if (empty_duration)
                empty_duration = av_rescale(empty_duration, sc->time_scale, mov->time_scale);
            sc->time_offset = start_time - empty_duration;
            sc->min_corrected_pts = start_time;
            if (!mov->advanced_editlist)
                current_dts = -sc->time_offset;
        }

        if (!multiple_edits && !mov->advanced_editlist &&
            st->codecpar->codec_id == AV_CODEC_ID_AAC && start_time > 0)
            sc->start_pad = start_time;
    }

    /* only use old uncompressed audio chunk demuxing when stts specifies it */
    if (!(st->codecpar->codec_type == AVMEDIA_TYPE_AUDIO &&
          sc->stts_count == 1 && sc->stts_data[0].duration == 1)) {
        unsigned int current_sample = 0;
        unsigned int stts_sample = 0;
        unsigned int sample_size;
        unsigned int distance = 0;
        unsigned int rap_group_index = 0;
        unsigned int rap_group_sample = 0;
        int64_t last_dts = 0;
        int64_t dts_correction = 0;
        int rap_group_present = sc->rap_group_count && sc->rap_group;
        int key_off = (sc->keyframe_count && sc->keyframes[0] > 0) || (sc->stps_count && sc->stps_data[0] > 0);

        current_dts -= sc->dts_shift;
        last_dts     = current_dts;

        if (!sc->sample_count || st->nb_index_entries)
            return;
        if (sc->sample_count >= UINT_MAX / sizeof(*st->index_entries) - st->nb_index_entries)
            return;
        if (av_reallocp_array(&st->index_entries,
                              st->nb_index_entries + sc->sample_count,
                              sizeof(*st->index_entries)) < 0) {
            st->nb_index_entries = 0;
            return;
        }
        st->index_entries_allocated_size = (st->nb_index_entries + sc->sample_count) * sizeof(*st->index_entries);

        if (ctts_data_old) {
            // Expand ctts entries such that we have a 1-1 mapping with samples
            if (sc->sample_count >= UINT_MAX / sizeof(*sc->ctts_data))
                return;
            sc->ctts_count = 0;
            sc->ctts_allocated_size = 0;
            sc->ctts_data = av_fast_realloc(NULL, &sc->ctts_allocated_size,
                                    sc->sample_count * sizeof(*sc->ctts_data));
            if (!sc->ctts_data) {
                av_free(ctts_data_old);
                return;
            }

            memset((uint8_t*)(sc->ctts_data), 0, sc->ctts_allocated_size);

            for (i = 0; i < ctts_count_old &&
                        sc->ctts_count < sc->sample_count; i++)
                for (j = 0; j < ctts_data_old[i].count &&
                            sc->ctts_count < sc->sample_count; j++)
                    add_ctts_entry(&sc->ctts_data, &sc->ctts_count,
                                   &sc->ctts_allocated_size, 1,
                                   ctts_data_old[i].duration);
            av_free(ctts_data_old);
        }

        for (i = 0; i < sc->chunk_count; i++) {
            int64_t next_offset = i+1 < sc->chunk_count ? sc->chunk_offsets[i+1] : INT64_MAX;
            current_offset = sc->chunk_offsets[i];
            while (mov_stsc_index_valid(stsc_index, sc->stsc_count) &&
                i + 1 == sc->stsc_data[stsc_index + 1].first)
                stsc_index++;

            if (next_offset > current_offset && sc->sample_size>0 && sc->sample_size < sc->stsz_sample_size &&
                sc->stsc_data[stsc_index].count * (int64_t)sc->stsz_sample_size > next_offset - current_offset) {
                av_log(mov->fc, AV_LOG_WARNING, "STSZ sample size %d invalid (too large), ignoring\n", sc->stsz_sample_size);
                sc->stsz_sample_size = sc->sample_size;
            }
            if (sc->stsz_sample_size>0 && sc->stsz_sample_size < sc->sample_size) {
                av_log(mov->fc, AV_LOG_WARNING, "STSZ sample size %d invalid (too small), ignoring\n", sc->stsz_sample_size);
                sc->stsz_sample_size = sc->sample_size;
            }

            for (j = 0; j < sc->stsc_data[stsc_index].count; j++) {
                int keyframe = 0;
                if (current_sample >= sc->sample_count) {
                    av_log(mov->fc, AV_LOG_ERROR, "wrong sample count\n");
                    return;
                }

                if (!sc->keyframe_absent && (!sc->keyframe_count || current_sample+key_off == sc->keyframes[stss_index])) {
                    keyframe = 1;
                    if (stss_index + 1 < sc->keyframe_count)
                        stss_index++;
                } else if (sc->stps_count && current_sample+key_off == sc->stps_data[stps_index]) {
                    keyframe = 1;
                    if (stps_index + 1 < sc->stps_count)
                        stps_index++;
                }
                if (rap_group_present && rap_group_index < sc->rap_group_count) {
                    if (sc->rap_group[rap_group_index].index > 0)
                        keyframe = 1;
                    if (++rap_group_sample == sc->rap_group[rap_group_index].count) {
                        rap_group_sample = 0;
                        rap_group_index++;
                    }
                }
                if (sc->keyframe_absent
                    && !sc->stps_count
                    && !rap_group_present
                    && (st->codecpar->codec_type == AVMEDIA_TYPE_AUDIO || (i==0 && j==0)))
                     keyframe = 1;
                if (keyframe)
                    distance = 0;
                sample_size = sc->stsz_sample_size > 0 ? sc->stsz_sample_size : sc->sample_sizes[current_sample];
                if (sc->pseudo_stream_id == -1 ||
                   sc->stsc_data[stsc_index].id - 1 == sc->pseudo_stream_id) {
                    AVIndexEntry *e;
                    if (sample_size > 0x3FFFFFFF) {
                        av_log(mov->fc, AV_LOG_ERROR, "Sample size %u is too large\n", sample_size);
                        return;
                    }
                    e = &st->index_entries[st->nb_index_entries++];
                    e->pos = current_offset;
                    e->timestamp = current_dts;
                    e->size = sample_size;
                    e->min_distance = distance;
                    e->flags = keyframe ? AVINDEX_KEYFRAME : 0;
                    av_log(mov->fc, AV_LOG_TRACE, "AVIndex stream %d, sample %u, offset %"PRIx64", dts %"PRId64", "
                            "size %u, distance %u, keyframe %d\n", st->index, current_sample,
                            current_offset, current_dts, sample_size, distance, keyframe);
                    if (st->codecpar->codec_type == AVMEDIA_TYPE_VIDEO && st->nb_index_entries < 100)
                        ff_rfps_add_frame(mov->fc, st, current_dts);
                }

                current_offset += sample_size;
                stream_size += sample_size;

                /* A negative sample duration is invalid based on the spec,
                 * but some samples need it to correct the DTS. */
                if (sc->stts_data[stts_index].duration < 0) {
                    av_log(mov->fc, AV_LOG_WARNING,
                           "Invalid SampleDelta %d in STTS, at %d st:%d\n",
                           sc->stts_data[stts_index].duration, stts_index,
                           st->index);
                    dts_correction += sc->stts_data[stts_index].duration - 1;
                    sc->stts_data[stts_index].duration = 1;
                }
                current_dts += sc->stts_data[stts_index].duration;
                if (!dts_correction || current_dts + dts_correction > last_dts) {
                    current_dts += dts_correction;
                    dts_correction = 0;
                } else {
                    /* Avoid creating non-monotonous DTS */
                    dts_correction += current_dts - last_dts - 1;
                    current_dts = last_dts + 1;
                }
                last_dts = current_dts;
                distance++;
                stts_sample++;
                current_sample++;
                if (stts_index + 1 < sc->stts_count && stts_sample == sc->stts_data[stts_index].count) {
                    stts_sample = 0;
                    stts_index++;
                }
            }
        }
        if (st->duration > 0)
            st->codecpar->bit_rate = stream_size*8*sc->time_scale/st->duration;
    } else {
        unsigned chunk_samples, total = 0;

        if (!sc->chunk_count)
            return;

        // compute total chunk count
        for (i = 0; i < sc->stsc_count; i++) {
            unsigned count, chunk_count;

            chunk_samples = sc->stsc_data[i].count;
            if (i != sc->stsc_count - 1 &&
                sc->samples_per_frame && chunk_samples % sc->samples_per_frame) {
                av_log(mov->fc, AV_LOG_ERROR, "error unaligned chunk\n");
                return;
            }

            if (sc->samples_per_frame >= 160) { // gsm
                count = chunk_samples / sc->samples_per_frame;
            } else if (sc->samples_per_frame > 1) {
                unsigned samples = (1024/sc->samples_per_frame)*sc->samples_per_frame;
                count = (chunk_samples+samples-1) / samples;
            } else {
                count = (chunk_samples+1023) / 1024;
            }

            if (mov_stsc_index_valid(i, sc->stsc_count))
                chunk_count = sc->stsc_data[i+1].first - sc->stsc_data[i].first;
            else
                chunk_count = sc->chunk_count - (sc->stsc_data[i].first - 1);
            total += chunk_count * count;
        }

        av_log(mov->fc, AV_LOG_TRACE, "chunk count %u\n", total);
        if (total >= UINT_MAX / sizeof(*st->index_entries) - st->nb_index_entries)
            return;
        if (av_reallocp_array(&st->index_entries,
                              st->nb_index_entries + total,
                              sizeof(*st->index_entries)) < 0) {
            st->nb_index_entries = 0;
            return;
        }
        st->index_entries_allocated_size = (st->nb_index_entries + total) * sizeof(*st->index_entries);

        // populate index
        for (i = 0; i < sc->chunk_count; i++) {
            current_offset = sc->chunk_offsets[i];
            if (mov_stsc_index_valid(stsc_index, sc->stsc_count) &&
                i + 1 == sc->stsc_data[stsc_index + 1].first)
                stsc_index++;
            chunk_samples = sc->stsc_data[stsc_index].count;

            while (chunk_samples > 0) {
                AVIndexEntry *e;
                unsigned size, samples;

                if (sc->samples_per_frame > 1 && !sc->bytes_per_frame) {
                    avpriv_request_sample(mov->fc,
                           "Zero bytes per frame, but %d samples per frame",
                           sc->samples_per_frame);
                    return;
                }

                if (sc->samples_per_frame >= 160) { // gsm
                    samples = sc->samples_per_frame;
                    size = sc->bytes_per_frame;
                } else {
                    if (sc->samples_per_frame > 1) {
                        samples = FFMIN((1024 / sc->samples_per_frame)*
                                        sc->samples_per_frame, chunk_samples);
                        size = (samples / sc->samples_per_frame) * sc->bytes_per_frame;
                    } else {
                        samples = FFMIN(1024, chunk_samples);
                        size = samples * sc->sample_size;
                    }
                }

                if (st->nb_index_entries >= total) {
                    av_log(mov->fc, AV_LOG_ERROR, "wrong chunk count %u\n", total);
                    return;
                }
                if (size > 0x3FFFFFFF) {
                    av_log(mov->fc, AV_LOG_ERROR, "Sample size %u is too large\n", size);
                    return;
                }
                e = &st->index_entries[st->nb_index_entries++];
                e->pos = current_offset;
                e->timestamp = current_dts;
                e->size = size;
                e->min_distance = 0;
                e->flags = AVINDEX_KEYFRAME;
                av_log(mov->fc, AV_LOG_TRACE, "AVIndex stream %d, chunk %u, offset %"PRIx64", dts %"PRId64", "
                       "size %u, duration %u\n", st->index, i, current_offset, current_dts,
                       size, samples);

                current_offset += size;
                current_dts += samples;
                chunk_samples -= samples;
            }
        }
    }

    if (!mov->ignore_editlist && mov->advanced_editlist) {
        // Fix index according to edit lists.
        mov_fix_index(mov, st);
    }

    mov_estimate_video_delay(mov, st);
}

static int test_same_origin(const char *src, const char *ref) {
    char src_proto[64];
    char ref_proto[64];
    char src_auth[256];
    char ref_auth[256];
    char src_host[256];
    char ref_host[256];
    int src_port=-1;
    int ref_port=-1;

    av_url_split(src_proto, sizeof(src_proto), src_auth, sizeof(src_auth), src_host, sizeof(src_host), &src_port, NULL, 0, src);
    av_url_split(ref_proto, sizeof(ref_proto), ref_auth, sizeof(ref_auth), ref_host, sizeof(ref_host), &ref_port, NULL, 0, ref);

    if (strlen(src) == 0) {
        return -1;
    } else if (strlen(src_auth) + 1 >= sizeof(src_auth) ||
        strlen(ref_auth) + 1 >= sizeof(ref_auth) ||
        strlen(src_host) + 1 >= sizeof(src_host) ||
        strlen(ref_host) + 1 >= sizeof(ref_host)) {
        return 0;
    } else if (strcmp(src_proto, ref_proto) ||
               strcmp(src_auth, ref_auth) ||
               strcmp(src_host, ref_host) ||
               src_port != ref_port) {
        return 0;
    } else
        return 1;
}

static int mov_open_dref(MOVContext *c, AVIOContext **pb, const char *src, MOVDref *ref)
{
    /* try relative path, we do not try the absolute because it can leak information about our
       system to an attacker */
    if (ref->nlvl_to > 0 && ref->nlvl_from > 0) {
        char filename[1025];
        const char *src_path;
        int i, l;

        /* find a source dir */
        src_path = strrchr(src, '/');
        if (src_path)
            src_path++;
        else
            src_path = src;

        /* find a next level down to target */
        for (i = 0, l = strlen(ref->path) - 1; l >= 0; l--)
            if (ref->path[l] == '/') {
                if (i == ref->nlvl_to - 1)
                    break;
                else
                    i++;
            }

        /* compose filename if next level down to target was found */
        if (i == ref->nlvl_to - 1 && src_path - src  < sizeof(filename)) {
            memcpy(filename, src, src_path - src);
            filename[src_path - src] = 0;

            for (i = 1; i < ref->nlvl_from; i++)
                av_strlcat(filename, "../", sizeof(filename));

            av_strlcat(filename, ref->path + l + 1, sizeof(filename));
            if (!c->use_absolute_path) {
                int same_origin = test_same_origin(src, filename);

                if (!same_origin) {
                    av_log(c->fc, AV_LOG_ERROR,
                        "Reference with mismatching origin, %s not tried for security reasons, "
                        "set demuxer option use_absolute_path to allow it anyway\n",
                        ref->path);
                    return AVERROR(ENOENT);
                }

                if(strstr(ref->path + l + 1, "..") ||
                   strstr(ref->path + l + 1, ":") ||
                   (ref->nlvl_from > 1 && same_origin < 0) ||
                   (filename[0] == '/' && src_path == src))
                    return AVERROR(ENOENT);
            }

            if (strlen(filename) + 1 == sizeof(filename))
                return AVERROR(ENOENT);
            if (!c->fc->io_open(c->fc, pb, filename, AVIO_FLAG_READ, NULL))
                return 0;
        }
    } else if (c->use_absolute_path) {
        av_log(c->fc, AV_LOG_WARNING, "Using absolute path on user request, "
               "this is a possible security issue\n");
        if (!c->fc->io_open(c->fc, pb, ref->path, AVIO_FLAG_READ, NULL))
            return 0;
    } else {
        av_log(c->fc, AV_LOG_ERROR,
               "Absolute path %s not tried for security reasons, "
               "set demuxer option use_absolute_path to allow absolute paths\n",
               ref->path);
    }

    return AVERROR(ENOENT);
}

static void fix_timescale(MOVContext *c, MOVStreamContext *sc)
{
    if (sc->time_scale <= 0) {
        av_log(c->fc, AV_LOG_WARNING, "stream %d, timescale not set\n", sc->ffindex);
        sc->time_scale = c->time_scale;
        if (sc->time_scale <= 0)
            sc->time_scale = 1;
    }
}

static int mov_read_trak(MOVContext *c, AVIOContext *pb, MOVAtom atom)
{
    AVStream *st;
    MOVStreamContext *sc;
    int ret;

    st = avformat_new_stream(c->fc, NULL);
    if (!st) return AVERROR(ENOMEM);
    st->id = -1;
    sc = av_mallocz(sizeof(MOVStreamContext));
    if (!sc) return AVERROR(ENOMEM);

    st->priv_data = sc;
    st->codecpar->codec_type = AVMEDIA_TYPE_DATA;
    sc->ffindex = st->index;
    c->trak_index = st->index;

    if ((ret = mov_read_default(c, pb, atom)) < 0)
        return ret;

    c->trak_index = -1;

    // Here stsc refers to a chunk not described in stco. This is technically invalid,
    // but we can overlook it (clearing stsc) whenever stts_count == 0 (indicating no samples).
    if (!sc->chunk_count && !sc->stts_count && sc->stsc_count) {
        sc->stsc_count = 0;
        av_freep(&sc->stsc_data);
    }

    /* sanity checks */
    if ((sc->chunk_count && (!sc->stts_count || !sc->stsc_count ||
                            (!sc->sample_size && !sc->sample_count))) ||
        (!sc->chunk_count && sc->sample_count)) {
        av_log(c->fc, AV_LOG_ERROR, "stream %d, missing mandatory atoms, broken header\n",
               st->index);
        return 0;
    }
    if (sc->stsc_count && sc->stsc_data[ sc->stsc_count - 1 ].first > sc->chunk_count) {
        av_log(c->fc, AV_LOG_ERROR, "stream %d, contradictionary STSC and STCO\n",
               st->index);
        return AVERROR_INVALIDDATA;
    }

    fix_timescale(c, sc);

    avpriv_set_pts_info(st, 64, 1, sc->time_scale);

    mov_build_index(c, st);

    if (sc->dref_id-1 < sc->drefs_count && sc->drefs[sc->dref_id-1].path) {
        MOVDref *dref = &sc->drefs[sc->dref_id - 1];
        if (c->enable_drefs) {
            if (mov_open_dref(c, &sc->pb, c->fc->url, dref) < 0)
                av_log(c->fc, AV_LOG_ERROR,
                       "stream %d, error opening alias: path='%s', dir='%s', "
                       "filename='%s', volume='%s', nlvl_from=%d, nlvl_to=%d\n",
                       st->index, dref->path, dref->dir, dref->filename,
                       dref->volume, dref->nlvl_from, dref->nlvl_to);
        } else {
            av_log(c->fc, AV_LOG_WARNING,
                   "Skipped opening external track: "
                   "stream %d, alias: path='%s', dir='%s', "
                   "filename='%s', volume='%s', nlvl_from=%d, nlvl_to=%d."
                   "Set enable_drefs to allow this.\n",
                   st->index, dref->path, dref->dir, dref->filename,
                   dref->volume, dref->nlvl_from, dref->nlvl_to);
        }
    } else {
        sc->pb = c->fc->pb;
        sc->pb_is_copied = 1;
    }

    if (st->codecpar->codec_type == AVMEDIA_TYPE_VIDEO) {
        if (!st->sample_aspect_ratio.num && st->codecpar->width && st->codecpar->height &&
            sc->height && sc->width &&
            (st->codecpar->width != sc->width || st->codecpar->height != sc->height)) {
            st->sample_aspect_ratio = av_d2q(((double)st->codecpar->height * sc->width) /
                                             ((double)st->codecpar->width * sc->height), INT_MAX);
        }

#if FF_API_R_FRAME_RATE
        if (sc->stts_count == 1 || (sc->stts_count == 2 && sc->stts_data[1].count == 1))
            av_reduce(&st->r_frame_rate.num, &st->r_frame_rate.den,
                      sc->time_scale, sc->stts_data[0].duration, INT_MAX);
#endif
    }

    // done for ai5q, ai52, ai55, ai1q, ai12 and ai15.
    if (!st->codecpar->extradata_size && st->codecpar->codec_id == AV_CODEC_ID_H264 &&
        TAG_IS_AVCI(st->codecpar->codec_tag)) {
        ret = ff_generate_avci_extradata(st);
        if (ret < 0)
            return ret;
    }

    switch (st->codecpar->codec_id) {
#if CONFIG_H261_DECODER
    case AV_CODEC_ID_H261:
#endif
#if CONFIG_H263_DECODER
    case AV_CODEC_ID_H263:
#endif
#if CONFIG_MPEG4_DECODER
    case AV_CODEC_ID_MPEG4:
#endif
        st->codecpar->width = 0; /* let decoder init width/height */
        st->codecpar->height= 0;
        break;
    }

    // If the duration of the mp3 packets is not constant, then they could need a parser
    if (st->codecpar->codec_id == AV_CODEC_ID_MP3
        && sc->stts_count > 3
        && sc->stts_count*10 > st->nb_frames
        && sc->time_scale == st->codecpar->sample_rate) {
            st->need_parsing = AVSTREAM_PARSE_FULL;
    }
    /* Do not need those anymore. */
    av_freep(&sc->chunk_offsets);
    av_freep(&sc->sample_sizes);
    av_freep(&sc->keyframes);
    av_freep(&sc->stts_data);
    av_freep(&sc->stps_data);
    av_freep(&sc->elst_data);
    av_freep(&sc->rap_group);

    return 0;
}

static int mov_read_ilst(MOVContext *c, AVIOContext *pb, MOVAtom atom)
{
    int ret;
    c->itunes_metadata = 1;
    ret = mov_read_default(c, pb, atom);
    c->itunes_metadata = 0;
    return ret;
}

static int mov_read_keys(MOVContext *c, AVIOContext *pb, MOVAtom atom)
{
    uint32_t count;
    uint32_t i;

    if (atom.size < 8)
        return 0;

    avio_skip(pb, 4);
    count = avio_rb32(pb);
    if (count > UINT_MAX / sizeof(*c->meta_keys) - 1) {
        av_log(c->fc, AV_LOG_ERROR,
               "The 'keys' atom with the invalid key count: %"PRIu32"\n", count);
        return AVERROR_INVALIDDATA;
    }

    c->meta_keys_count = count + 1;
    c->meta_keys = av_mallocz(c->meta_keys_count * sizeof(*c->meta_keys));
    if (!c->meta_keys)
        return AVERROR(ENOMEM);

    for (i = 1; i <= count; ++i) {
        uint32_t key_size = avio_rb32(pb);
        uint32_t type = avio_rl32(pb);
        if (key_size < 8) {
            av_log(c->fc, AV_LOG_ERROR,
                   "The key# %"PRIu32" in meta has invalid size:"
                   "%"PRIu32"\n", i, key_size);
            return AVERROR_INVALIDDATA;
        }
        key_size -= 8;
        if (type != MKTAG('m','d','t','a')) {
            avio_skip(pb, key_size);
        }
        c->meta_keys[i] = av_mallocz(key_size + 1);
        if (!c->meta_keys[i])
            return AVERROR(ENOMEM);
        avio_read(pb, c->meta_keys[i], key_size);
    }

    return 0;
}

static int mov_read_custom(MOVContext *c, AVIOContext *pb, MOVAtom atom)
{
    int64_t end = avio_tell(pb) + atom.size;
    uint8_t *key = NULL, *val = NULL, *mean = NULL;
    int i;
    int ret = 0;
    AVStream *st;
    MOVStreamContext *sc;

    if (c->fc->nb_streams < 1)
        return 0;
    st = c->fc->streams[c->fc->nb_streams-1];
    sc = st->priv_data;

    for (i = 0; i < 3; i++) {
        uint8_t **p;
        uint32_t len, tag;

        if (end - avio_tell(pb) <= 12)
            break;

        len = avio_rb32(pb);
        tag = avio_rl32(pb);
        avio_skip(pb, 4); // flags

        if (len < 12 || len - 12 > end - avio_tell(pb))
            break;
        len -= 12;

        if (tag == MKTAG('m', 'e', 'a', 'n'))
            p = &mean;
        else if (tag == MKTAG('n', 'a', 'm', 'e'))
            p = &key;
        else if (tag == MKTAG('d', 'a', 't', 'a') && len > 4) {
            avio_skip(pb, 4);
            len -= 4;
            p = &val;
        } else
            break;

        *p = av_malloc(len + 1);
        if (!*p) {
            ret = AVERROR(ENOMEM);
            break;
        }
        ret = ffio_read_size(pb, *p, len);
        if (ret < 0) {
            av_freep(p);
            break;
        }
        (*p)[len] = 0;
    }

    if (mean && key && val) {
        if (strcmp(key, "iTunSMPB") == 0) {
            int priming, remainder, samples;
            if(sscanf(val, "%*X %X %X %X", &priming, &remainder, &samples) == 3){
                if(priming>0 && priming<16384)
                    sc->start_pad = priming;
            }
        }
        if (strcmp(key, "cdec") != 0) {
            av_dict_set(&c->fc->metadata, key, val,
                        AV_DICT_DONT_STRDUP_KEY | AV_DICT_DONT_STRDUP_VAL);
            key = val = NULL;
        }
    } else {
        av_log(c->fc, AV_LOG_VERBOSE,
               "Unhandled or malformed custom metadata of size %"PRId64"\n", atom.size);
    }

    avio_seek(pb, end, SEEK_SET);
    av_freep(&key);
    av_freep(&val);
    av_freep(&mean);
    return ret;
}

static int mov_read_meta(MOVContext *c, AVIOContext *pb, MOVAtom atom)
{
    while (atom.size > 8) {
        uint32_t tag = avio_rl32(pb);
        atom.size -= 4;
        if (tag == MKTAG('h','d','l','r')) {
            avio_seek(pb, -8, SEEK_CUR);
            atom.size += 8;
            return mov_read_default(c, pb, atom);
        }
    }
    return 0;
}

// return 1 when matrix is identity, 0 otherwise
#define IS_MATRIX_IDENT(matrix)            \
    ( (matrix)[0][0] == (1 << 16) &&       \
      (matrix)[1][1] == (1 << 16) &&       \
      (matrix)[2][2] == (1 << 30) &&       \
     !(matrix)[0][1] && !(matrix)[0][2] && \
     !(matrix)[1][0] && !(matrix)[1][2] && \
     !(matrix)[2][0] && !(matrix)[2][1])

static int mov_read_tkhd(MOVContext *c, AVIOContext *pb, MOVAtom atom)
{
    int i, j, e;
    int width;
    int height;
    int display_matrix[3][3];
    int res_display_matrix[3][3] = { { 0 } };
    AVStream *st;
    MOVStreamContext *sc;
    int version;
    int flags;

    if (c->fc->nb_streams < 1)
        return 0;
    st = c->fc->streams[c->fc->nb_streams-1];
    sc = st->priv_data;

    // Each stream (trak) should have exactly 1 tkhd. This catches bad files and
    // avoids corrupting AVStreams mapped to an earlier tkhd.
    if (st->id != -1)
        return AVERROR_INVALIDDATA;

    version = avio_r8(pb);
    flags = avio_rb24(pb);
    st->disposition |= (flags & MOV_TKHD_FLAG_ENABLED) ? AV_DISPOSITION_DEFAULT : 0;

    if (version == 1) {
        avio_rb64(pb);
        avio_rb64(pb);
    } else {
        avio_rb32(pb); /* creation time */
        avio_rb32(pb); /* modification time */
    }
    st->id = (int)avio_rb32(pb); /* track id (NOT 0 !)*/
    avio_rb32(pb); /* reserved */

    /* highlevel (considering edits) duration in movie timebase */
    (version == 1) ? avio_rb64(pb) : avio_rb32(pb);
    avio_rb32(pb); /* reserved */
    avio_rb32(pb); /* reserved */

    avio_rb16(pb); /* layer */
    avio_rb16(pb); /* alternate group */
    avio_rb16(pb); /* volume */
    avio_rb16(pb); /* reserved */

    //read in the display matrix (outlined in ISO 14496-12, Section 6.2.2)
    // they're kept in fixed point format through all calculations
    // save u,v,z to store the whole matrix in the AV_PKT_DATA_DISPLAYMATRIX
    // side data, but the scale factor is not needed to calculate aspect ratio
    for (i = 0; i < 3; i++) {
        display_matrix[i][0] = avio_rb32(pb);   // 16.16 fixed point
        display_matrix[i][1] = avio_rb32(pb);   // 16.16 fixed point
        display_matrix[i][2] = avio_rb32(pb);   //  2.30 fixed point
    }

    width = avio_rb32(pb);       // 16.16 fixed point track width
    height = avio_rb32(pb);      // 16.16 fixed point track height
    sc->width = width >> 16;
    sc->height = height >> 16;

    // apply the moov display matrix (after the tkhd one)
    for (i = 0; i < 3; i++) {
        const int sh[3] = { 16, 16, 30 };
        for (j = 0; j < 3; j++) {
            for (e = 0; e < 3; e++) {
                res_display_matrix[i][j] +=
                    ((int64_t) display_matrix[i][e] *
                     c->movie_display_matrix[e][j]) >> sh[e];
            }
        }
    }

    // save the matrix when it is not the default identity
    if (!IS_MATRIX_IDENT(res_display_matrix)) {
        double rotate;

        av_freep(&sc->display_matrix);
        sc->display_matrix = av_malloc(sizeof(int32_t) * 9);
        if (!sc->display_matrix)
            return AVERROR(ENOMEM);

        for (i = 0; i < 3; i++)
            for (j = 0; j < 3; j++)
                sc->display_matrix[i * 3 + j] = res_display_matrix[i][j];

#if FF_API_OLD_ROTATE_API
        rotate = av_display_rotation_get(sc->display_matrix);
        if (!isnan(rotate)) {
            char rotate_buf[64];
            rotate = -rotate;
            if (rotate < 0) // for backward compatibility
                rotate += 360;
            snprintf(rotate_buf, sizeof(rotate_buf), "%g", rotate);
            av_dict_set(&st->metadata, "rotate", rotate_buf, 0);
        }
#endif
    }

    // transform the display width/height according to the matrix
    // to keep the same scale, use [width height 1<<16]
    if (width && height && sc->display_matrix) {
        double disp_transform[2];

        for (i = 0; i < 2; i++)
            disp_transform[i] = hypot(sc->display_matrix[0 + i],
                                      sc->display_matrix[3 + i]);

        if (disp_transform[0] > 0       && disp_transform[1] > 0 &&
            disp_transform[0] < (1<<24) && disp_transform[1] < (1<<24) &&
            fabs((disp_transform[0] / disp_transform[1]) - 1.0) > 0.01)
            st->sample_aspect_ratio = av_d2q(
                disp_transform[0] / disp_transform[1],
                INT_MAX);
    }
    return 0;
}

static int mov_read_tfhd(MOVContext *c, AVIOContext *pb, MOVAtom atom)
{
    MOVFragment *frag = &c->fragment;
    MOVTrackExt *trex = NULL;
    int flags, track_id, i;

    c->fragment.found_tfhd = 1;

    avio_r8(pb); /* version */
    flags = avio_rb24(pb);

    track_id = avio_rb32(pb);
    if (!track_id)
        return AVERROR_INVALIDDATA;
    frag->track_id = track_id;
    set_frag_stream(&c->frag_index, track_id);
    for (i = 0; i < c->trex_count; i++)
        if (c->trex_data[i].track_id == frag->track_id) {
            trex = &c->trex_data[i];
            break;
        }
    if (!trex) {
        av_log(c->fc, AV_LOG_ERROR, "could not find corresponding trex\n");
        return AVERROR_INVALIDDATA;
    }

    frag->base_data_offset = flags & MOV_TFHD_BASE_DATA_OFFSET ?
                             avio_rb64(pb) : flags & MOV_TFHD_DEFAULT_BASE_IS_MOOF ?
                             frag->moof_offset : frag->implicit_offset;
    frag->stsd_id  = flags & MOV_TFHD_STSD_ID ? avio_rb32(pb) : trex->stsd_id;

    frag->duration = flags & MOV_TFHD_DEFAULT_DURATION ?
                     avio_rb32(pb) : trex->duration;
    frag->size     = flags & MOV_TFHD_DEFAULT_SIZE ?
                     avio_rb32(pb) : trex->size;
    frag->flags    = flags & MOV_TFHD_DEFAULT_FLAGS ?
                     avio_rb32(pb) : trex->flags;
    av_log(c->fc, AV_LOG_TRACE, "frag flags 0x%x\n", frag->flags);

    return 0;
}

static int mov_read_chap(MOVContext *c, AVIOContext *pb, MOVAtom atom)
{
    unsigned i, num;
    void *new_tracks;

    num = atom.size / 4;
    if (!(new_tracks = av_malloc_array(num, sizeof(int))))
        return AVERROR(ENOMEM);

    av_free(c->chapter_tracks);
    c->chapter_tracks = new_tracks;
    c->nb_chapter_tracks = num;

    for (i = 0; i < num && !pb->eof_reached; i++)
        c->chapter_tracks[i] = avio_rb32(pb);

    return 0;
}

static int mov_read_trex(MOVContext *c, AVIOContext *pb, MOVAtom atom)
{
    MOVTrackExt *trex;
    int err;

    if ((uint64_t)c->trex_count+1 >= UINT_MAX / sizeof(*c->trex_data))
        return AVERROR_INVALIDDATA;
    if ((err = av_reallocp_array(&c->trex_data, c->trex_count + 1,
                                 sizeof(*c->trex_data))) < 0) {
        c->trex_count = 0;
        return err;
    }

    c->fc->duration = AV_NOPTS_VALUE; // the duration from mvhd is not representing the whole file when fragments are used.

    trex = &c->trex_data[c->trex_count++];
    avio_r8(pb); /* version */
    avio_rb24(pb); /* flags */
    trex->track_id = avio_rb32(pb);
    trex->stsd_id  = avio_rb32(pb);
    trex->duration = avio_rb32(pb);
    trex->size     = avio_rb32(pb);
    trex->flags    = avio_rb32(pb);
    return 0;
}

static int mov_read_tfdt(MOVContext *c, AVIOContext *pb, MOVAtom atom)
{
    MOVFragment *frag = &c->fragment;
    AVStream *st = NULL;
    MOVStreamContext *sc;
    int version, i;
    MOVFragmentStreamInfo * frag_stream_info;
    int64_t base_media_decode_time;

    for (i = 0; i < c->fc->nb_streams; i++) {
        if (c->fc->streams[i]->id == frag->track_id) {
            st = c->fc->streams[i];
            break;
        }
    }
    if (!st) {
        av_log(c->fc, AV_LOG_ERROR, "could not find corresponding track id %u\n", frag->track_id);
        return AVERROR_INVALIDDATA;
    }
    sc = st->priv_data;
    if (sc->pseudo_stream_id + 1 != frag->stsd_id && sc->pseudo_stream_id != -1)
        return 0;
    version = avio_r8(pb);
    avio_rb24(pb); /* flags */
    if (version) {
        base_media_decode_time = avio_rb64(pb);
    } else {
        base_media_decode_time = avio_rb32(pb);
    }

    frag_stream_info = get_current_frag_stream_info(&c->frag_index);
    if (frag_stream_info)
        frag_stream_info->tfdt_dts = base_media_decode_time;
    sc->track_end = base_media_decode_time;

    return 0;
}

static int mov_read_trun(MOVContext *c, AVIOContext *pb, MOVAtom atom)
{
    MOVFragment *frag = &c->fragment;
    AVStream *st = NULL;
    MOVStreamContext *sc;
    MOVStts *ctts_data;
    uint64_t offset;
    int64_t dts, pts = AV_NOPTS_VALUE;
    int data_offset = 0;
    unsigned entries, first_sample_flags = frag->flags;
    int flags, distance, i;
    int64_t prev_dts = AV_NOPTS_VALUE;
    int next_frag_index = -1, index_entry_pos;
    size_t requested_size;
    size_t old_ctts_allocated_size;
    AVIndexEntry *new_entries;
    MOVFragmentStreamInfo * frag_stream_info;

    if (!frag->found_tfhd) {
        av_log(c->fc, AV_LOG_ERROR, "trun track id unknown, no tfhd was found\n");
        return AVERROR_INVALIDDATA;
    }

    for (i = 0; i < c->fc->nb_streams; i++) {
        if (c->fc->streams[i]->id == frag->track_id) {
            st = c->fc->streams[i];
            break;
        }
    }
    if (!st) {
        av_log(c->fc, AV_LOG_ERROR, "could not find corresponding track id %u\n", frag->track_id);
        return AVERROR_INVALIDDATA;
    }
    sc = st->priv_data;
    if (sc->pseudo_stream_id+1 != frag->stsd_id && sc->pseudo_stream_id != -1)
        return 0;

    // Find the next frag_index index that has a valid index_entry for
    // the current track_id.
    //
    // A valid index_entry means the trun for the fragment was read
    // and it's samples are in index_entries at the given position.
    // New index entries will be inserted before the index_entry found.
    index_entry_pos = st->nb_index_entries;
    for (i = c->frag_index.current + 1; i < c->frag_index.nb_items; i++) {
        frag_stream_info = get_frag_stream_info(&c->frag_index, i, frag->track_id);
        if (frag_stream_info && frag_stream_info->index_entry >= 0) {
            next_frag_index = i;
            index_entry_pos = frag_stream_info->index_entry;
            break;
        }
    }
    av_assert0(index_entry_pos <= st->nb_index_entries);

    avio_r8(pb); /* version */
    flags = avio_rb24(pb);
    entries = avio_rb32(pb);
    av_log(c->fc, AV_LOG_TRACE, "flags 0x%x entries %u\n", flags, entries);

    if ((uint64_t)entries+sc->ctts_count >= UINT_MAX/sizeof(*sc->ctts_data))
        return AVERROR_INVALIDDATA;
    if (flags & MOV_TRUN_DATA_OFFSET)        data_offset        = avio_rb32(pb);
    if (flags & MOV_TRUN_FIRST_SAMPLE_FLAGS) first_sample_flags = avio_rb32(pb);

    frag_stream_info = get_current_frag_stream_info(&c->frag_index);
    if (frag_stream_info)
    {
        if (frag_stream_info->first_tfra_pts != AV_NOPTS_VALUE &&
            c->use_mfra_for == FF_MOV_FLAG_MFRA_PTS) {
            pts = frag_stream_info->first_tfra_pts;
            av_log(c->fc, AV_LOG_DEBUG, "found mfra time %"PRId64
                    ", using it for pts\n", pts);
        } else if (frag_stream_info->sidx_pts != AV_NOPTS_VALUE) {
            // FIXME: sidx earliest_presentation_time is *PTS*, s.b.
            // pts = frag_stream_info->sidx_pts;
            dts = frag_stream_info->sidx_pts - sc->time_offset;
            av_log(c->fc, AV_LOG_DEBUG, "found sidx time %"PRId64
                    ", using it for pts\n", pts);
        } else if (frag_stream_info->tfdt_dts != AV_NOPTS_VALUE) {
            dts = frag_stream_info->tfdt_dts - sc->time_offset;
            av_log(c->fc, AV_LOG_DEBUG, "found tfdt time %"PRId64
                    ", using it for dts\n", dts);
        } else {
            dts = sc->track_end - sc->time_offset;
            av_log(c->fc, AV_LOG_DEBUG, "found track end time %"PRId64
                    ", using it for dts\n", dts);
        }
    } else {
        dts = sc->track_end - sc->time_offset;
        av_log(c->fc, AV_LOG_DEBUG, "found track end time %"PRId64
                ", using it for dts\n", dts);
    }
    offset   = frag->base_data_offset + data_offset;
    distance = 0;
    av_log(c->fc, AV_LOG_TRACE, "first sample flags 0x%x\n", first_sample_flags);

    // realloc space for new index entries
    if((unsigned)st->nb_index_entries + entries >= UINT_MAX / sizeof(AVIndexEntry)) {
        entries = UINT_MAX / sizeof(AVIndexEntry) - st->nb_index_entries;
        av_log(c->fc, AV_LOG_ERROR, "Failed to add index entry\n");
    }
    if (entries <= 0)
        return -1;

    requested_size = (st->nb_index_entries + entries) * sizeof(AVIndexEntry);
    new_entries = av_fast_realloc(st->index_entries,
                                  &st->index_entries_allocated_size,
                                  requested_size);
    if(!new_entries)
        return AVERROR(ENOMEM);
    st->index_entries= new_entries;

    requested_size = (st->nb_index_entries + entries) * sizeof(*sc->ctts_data);
    old_ctts_allocated_size = sc->ctts_allocated_size;
    ctts_data = av_fast_realloc(sc->ctts_data, &sc->ctts_allocated_size,
                                requested_size);
    if (!ctts_data)
        return AVERROR(ENOMEM);
    sc->ctts_data = ctts_data;

    // In case there were samples without ctts entries, ensure they get
    // zero valued entries. This ensures clips which mix boxes with and
    // without ctts entries don't pickup uninitialized data.
    memset((uint8_t*)(sc->ctts_data) + old_ctts_allocated_size, 0,
           sc->ctts_allocated_size - old_ctts_allocated_size);

    if (index_entry_pos < st->nb_index_entries) {
        // Make hole in index_entries and ctts_data for new samples
        memmove(st->index_entries + index_entry_pos + entries,
                st->index_entries + index_entry_pos,
                sizeof(*st->index_entries) *
                (st->nb_index_entries - index_entry_pos));
        memmove(sc->ctts_data + index_entry_pos + entries,
                sc->ctts_data + index_entry_pos,
                sizeof(*sc->ctts_data) * (sc->ctts_count - index_entry_pos));
        if (index_entry_pos < sc->current_sample) {
            sc->current_sample += entries;
        }
    }

    st->nb_index_entries += entries;
    sc->ctts_count = st->nb_index_entries;

    // Record the index_entry position in frag_index of this fragment
    if (frag_stream_info)
        frag_stream_info->index_entry = index_entry_pos;

    if (index_entry_pos > 0)
        prev_dts = st->index_entries[index_entry_pos-1].timestamp;

    for (i = 0; i < entries && !pb->eof_reached; i++) {
        unsigned sample_size = frag->size;
        int sample_flags = i ? frag->flags : first_sample_flags;
        unsigned sample_duration = frag->duration;
        unsigned ctts_duration = 0;
        int keyframe = 0;
        int index_entry_flags = 0;

        if (flags & MOV_TRUN_SAMPLE_DURATION) sample_duration = avio_rb32(pb);
        if (flags & MOV_TRUN_SAMPLE_SIZE)     sample_size     = avio_rb32(pb);
        if (flags & MOV_TRUN_SAMPLE_FLAGS)    sample_flags    = avio_rb32(pb);
        if (flags & MOV_TRUN_SAMPLE_CTS)      ctts_duration   = avio_rb32(pb);

        mov_update_dts_shift(sc, ctts_duration);
        if (pts != AV_NOPTS_VALUE) {
            dts = pts - sc->dts_shift;
            if (flags & MOV_TRUN_SAMPLE_CTS) {
                dts -= ctts_duration;
            } else {
                dts -= sc->time_offset;
            }
            av_log(c->fc, AV_LOG_DEBUG,
                   "pts %"PRId64" calculated dts %"PRId64
                   " sc->dts_shift %d ctts.duration %d"
                   " sc->time_offset %"PRId64
                   " flags & MOV_TRUN_SAMPLE_CTS %d\n",
                   pts, dts,
                   sc->dts_shift, ctts_duration,
                   sc->time_offset, flags & MOV_TRUN_SAMPLE_CTS);
            pts = AV_NOPTS_VALUE;
        }

        if (st->codecpar->codec_type == AVMEDIA_TYPE_AUDIO)
            keyframe = 1;
        else
            keyframe =
                !(sample_flags & (MOV_FRAG_SAMPLE_FLAG_IS_NON_SYNC |
                                  MOV_FRAG_SAMPLE_FLAG_DEPENDS_YES));
        if (keyframe) {
            distance = 0;
            index_entry_flags |= AVINDEX_KEYFRAME;
        }
        // Fragments can overlap in time.  Discard overlapping frames after
        // decoding.
        if (prev_dts >= dts)
            index_entry_flags |= AVINDEX_DISCARD_FRAME;

        st->index_entries[index_entry_pos].pos = offset;
        st->index_entries[index_entry_pos].timestamp = dts;
        st->index_entries[index_entry_pos].size= sample_size;
        st->index_entries[index_entry_pos].min_distance= distance;
        st->index_entries[index_entry_pos].flags = index_entry_flags;

        sc->ctts_data[index_entry_pos].count = 1;
        sc->ctts_data[index_entry_pos].duration = ctts_duration;
        index_entry_pos++;

        av_log(c->fc, AV_LOG_TRACE, "AVIndex stream %d, sample %d, offset %"PRIx64", dts %"PRId64", "
                "size %u, distance %d, keyframe %d\n", st->index,
                index_entry_pos, offset, dts, sample_size, distance, keyframe);
        distance++;
        dts += sample_duration;
        offset += sample_size;
        sc->data_size += sample_size;

        if (sample_duration <= INT64_MAX - sc->duration_for_fps &&
            1 <= INT64_MAX - sc->nb_frames_for_fps
        ) {
            sc->duration_for_fps += sample_duration;
            sc->nb_frames_for_fps ++;
        }
    }
    if (i < entries) {
        // EOF found before reading all entries.  Fix the hole this would
        // leave in index_entries and ctts_data
        int gap = entries - i;
        memmove(st->index_entries + index_entry_pos,
                st->index_entries + index_entry_pos + gap,
                sizeof(*st->index_entries) *
                (st->nb_index_entries - (index_entry_pos + gap)));
        memmove(sc->ctts_data + index_entry_pos,
                sc->ctts_data + index_entry_pos + gap,
                sizeof(*sc->ctts_data) *
                (sc->ctts_count - (index_entry_pos + gap)));

        st->nb_index_entries -= gap;
        sc->ctts_count -= gap;
        if (index_entry_pos < sc->current_sample) {
            sc->current_sample -= gap;
        }
        entries = i;
    }

    // The end of this new fragment may overlap in time with the start
    // of the next fragment in index_entries. Mark the samples in the next
    // fragment that overlap with AVINDEX_DISCARD_FRAME
    prev_dts = AV_NOPTS_VALUE;
    if (index_entry_pos > 0)
        prev_dts = st->index_entries[index_entry_pos-1].timestamp;
    for (i = index_entry_pos; i < st->nb_index_entries; i++) {
        if (prev_dts < st->index_entries[i].timestamp)
            break;
        st->index_entries[i].flags |= AVINDEX_DISCARD_FRAME;
    }

    // If a hole was created to insert the new index_entries into,
    // the index_entry recorded for all subsequent moof must
    // be incremented by the number of entries inserted.
    fix_frag_index_entries(&c->frag_index, next_frag_index,
                           frag->track_id, entries);

    if (pb->eof_reached) {
        av_log(c->fc, AV_LOG_WARNING, "reached eof, corrupted TRUN atom\n");
        return AVERROR_EOF;
    }

    frag->implicit_offset = offset;

    sc->track_end = dts + sc->time_offset;
    if (st->duration < sc->track_end)
        st->duration = sc->track_end;

    return 0;
}

static int mov_read_sidx(MOVContext *c, AVIOContext *pb, MOVAtom atom)
{
    int64_t offset = avio_tell(pb) + atom.size, pts, timestamp;
    uint8_t version;
    unsigned i, j, track_id, item_count;
    AVStream *st = NULL;
    AVStream *ref_st = NULL;
    MOVStreamContext *sc, *ref_sc = NULL;
    AVRational timescale;

    version = avio_r8(pb);
    if (version > 1) {
        avpriv_request_sample(c->fc, "sidx version %u", version);
        return 0;
    }

    avio_rb24(pb); // flags

    track_id = avio_rb32(pb); // Reference ID
    for (i = 0; i < c->fc->nb_streams; i++) {
        if (c->fc->streams[i]->id == track_id) {
            st = c->fc->streams[i];
            break;
        }
    }
    if (!st) {
        av_log(c->fc, AV_LOG_WARNING, "could not find corresponding track id %d\n", track_id);
        return 0;
    }

    sc = st->priv_data;

    timescale = av_make_q(1, avio_rb32(pb));

    if (timescale.den <= 0) {
        av_log(c->fc, AV_LOG_ERROR, "Invalid sidx timescale 1/%d\n", timescale.den);
        return AVERROR_INVALIDDATA;
    }

    if (version == 0) {
        pts = avio_rb32(pb);
        offset += avio_rb32(pb);
    } else {
        pts = avio_rb64(pb);
        offset += avio_rb64(pb);
    }

    avio_rb16(pb); // reserved

    item_count = avio_rb16(pb);

    for (i = 0; i < item_count; i++) {
        int index;
        MOVFragmentStreamInfo * frag_stream_info;
        uint32_t size = avio_rb32(pb);
        uint32_t duration = avio_rb32(pb);
        if (size & 0x80000000) {
            avpriv_request_sample(c->fc, "sidx reference_type 1");
            return AVERROR_PATCHWELCOME;
        }
        avio_rb32(pb); // sap_flags
        timestamp = av_rescale_q(pts, st->time_base, timescale);

        index = update_frag_index(c, offset);
        frag_stream_info = get_frag_stream_info(&c->frag_index, index, track_id);
        if (frag_stream_info)
            frag_stream_info->sidx_pts = timestamp;

        offset += size;
        pts += duration;
    }

    st->duration = sc->track_end = pts;

    sc->has_sidx = 1;

    if (offset == avio_size(pb)) {
        // Find first entry in fragment index that came from an sidx.
        // This will pretty much always be the first entry.
        for (i = 0; i < c->frag_index.nb_items; i++) {
            MOVFragmentIndexItem * item = &c->frag_index.item[i];
            for (j = 0; ref_st == NULL && j < item->nb_stream_info; j++) {
                MOVFragmentStreamInfo * si;
                si = &item->stream_info[j];
                if (si->sidx_pts != AV_NOPTS_VALUE) {
                    ref_st = c->fc->streams[j];
                    ref_sc = ref_st->priv_data;
                    break;
                }
            }
        }
        for (i = 0; i < c->fc->nb_streams; i++) {
            st = c->fc->streams[i];
            sc = st->priv_data;
            if (!sc->has_sidx) {
                st->duration = sc->track_end = av_rescale(ref_st->duration, sc->time_scale, ref_sc->time_scale);
            }
        }

        c->frag_index.complete = 1;
    }

    return 0;
}

/* this atom should be null (from specs), but some buggy files put the 'moov' atom inside it... */
/* like the files created with Adobe Premiere 5.0, for samples see */
/* http://graphics.tudelft.nl/~wouter/publications/soundtests/ */
static int mov_read_wide(MOVContext *c, AVIOContext *pb, MOVAtom atom)
{
    int err;

    if (atom.size < 8)
        return 0; /* continue */
    if (avio_rb32(pb) != 0) { /* 0 sized mdat atom... use the 'wide' atom size */
        avio_skip(pb, atom.size - 4);
        return 0;
    }
    atom.type = avio_rl32(pb);
    atom.size -= 8;
    if (atom.type != MKTAG('m','d','a','t')) {
        avio_skip(pb, atom.size);
        return 0;
    }
    err = mov_read_mdat(c, pb, atom);
    return err;
}

static int mov_read_cmov(MOVContext *c, AVIOContext *pb, MOVAtom atom)
{
#if CONFIG_ZLIB
    AVIOContext ctx;
    uint8_t *cmov_data;
    uint8_t *moov_data; /* uncompressed data */
    long cmov_len, moov_len;
    int ret = -1;

    avio_rb32(pb); /* dcom atom */
    if (avio_rl32(pb) != MKTAG('d','c','o','m'))
        return AVERROR_INVALIDDATA;
    if (avio_rl32(pb) != MKTAG('z','l','i','b')) {
        av_log(c->fc, AV_LOG_ERROR, "unknown compression for cmov atom !\n");
        return AVERROR_INVALIDDATA;
    }
    avio_rb32(pb); /* cmvd atom */
    if (avio_rl32(pb) != MKTAG('c','m','v','d'))
        return AVERROR_INVALIDDATA;
    moov_len = avio_rb32(pb); /* uncompressed size */
    cmov_len = atom.size - 6 * 4;

    cmov_data = av_malloc(cmov_len);
    if (!cmov_data)
        return AVERROR(ENOMEM);
    moov_data = av_malloc(moov_len);
    if (!moov_data) {
        av_free(cmov_data);
        return AVERROR(ENOMEM);
    }
    ret = ffio_read_size(pb, cmov_data, cmov_len);
    if (ret < 0)
        goto free_and_return;

    ret = AVERROR_INVALIDDATA;
    if (uncompress (moov_data, (uLongf *) &moov_len, (const Bytef *)cmov_data, cmov_len) != Z_OK)
        goto free_and_return;
    if (ffio_init_context(&ctx, moov_data, moov_len, 0, NULL, NULL, NULL, NULL) != 0)
        goto free_and_return;
    ctx.seekable = AVIO_SEEKABLE_NORMAL;
    atom.type = MKTAG('m','o','o','v');
    atom.size = moov_len;
    ret = mov_read_default(c, &ctx, atom);
free_and_return:
    av_free(moov_data);
    av_free(cmov_data);
    return ret;
#else
    av_log(c->fc, AV_LOG_ERROR, "this file requires zlib support compiled in\n");
    return AVERROR(ENOSYS);
#endif
}

/* edit list atom */
static int mov_read_elst(MOVContext *c, AVIOContext *pb, MOVAtom atom)
{
    MOVStreamContext *sc;
    int i, edit_count, version;
    int64_t elst_entry_size;

    if (c->fc->nb_streams < 1 || c->ignore_editlist)
        return 0;
    sc = c->fc->streams[c->fc->nb_streams-1]->priv_data;

    version = avio_r8(pb); /* version */
    avio_rb24(pb); /* flags */
    edit_count = avio_rb32(pb); /* entries */
    atom.size -= 8;

    elst_entry_size = version == 1 ? 20 : 12;
    if (atom.size != edit_count * elst_entry_size) {
        if (c->fc->strict_std_compliance >= FF_COMPLIANCE_STRICT) {
            av_log(c->fc, AV_LOG_ERROR, "Invalid edit list entry_count: %d for elst atom of size: %"PRId64" bytes.\n",
                   edit_count, atom.size + 8);
            return AVERROR_INVALIDDATA;
        } else {
            edit_count = atom.size / elst_entry_size;
            if (edit_count * elst_entry_size != atom.size) {
                av_log(c->fc, AV_LOG_WARNING, "ELST atom of %"PRId64" bytes, bigger than %d entries.", atom.size, edit_count);
            }
        }
    }

    if (!edit_count)
        return 0;
    if (sc->elst_data)
        av_log(c->fc, AV_LOG_WARNING, "Duplicated ELST atom\n");
    av_free(sc->elst_data);
    sc->elst_count = 0;
    sc->elst_data = av_malloc_array(edit_count, sizeof(*sc->elst_data));
    if (!sc->elst_data)
        return AVERROR(ENOMEM);

    av_log(c->fc, AV_LOG_TRACE, "track[%u].edit_count = %i\n", c->fc->nb_streams - 1, edit_count);
    for (i = 0; i < edit_count && atom.size > 0 && !pb->eof_reached; i++) {
        MOVElst *e = &sc->elst_data[i];

        if (version == 1) {
            e->duration = avio_rb64(pb);
            e->time     = avio_rb64(pb);
            atom.size -= 16;
        } else {
            e->duration = avio_rb32(pb); /* segment duration */
            e->time     = (int32_t)avio_rb32(pb); /* media time */
            atom.size -= 8;
        }
        e->rate = avio_rb32(pb) / 65536.0;
        atom.size -= 4;
        av_log(c->fc, AV_LOG_TRACE, "duration=%"PRId64" time=%"PRId64" rate=%f\n",
               e->duration, e->time, e->rate);

        if (e->time < 0 && e->time != -1 &&
            c->fc->strict_std_compliance >= FF_COMPLIANCE_STRICT) {
            av_log(c->fc, AV_LOG_ERROR, "Track %d, edit %d: Invalid edit list media time=%"PRId64"\n",
                   c->fc->nb_streams-1, i, e->time);
            return AVERROR_INVALIDDATA;
        }
    }
    sc->elst_count = i;

    return 0;
}

static int mov_read_tmcd(MOVContext *c, AVIOContext *pb, MOVAtom atom)
{
    MOVStreamContext *sc;

    if (c->fc->nb_streams < 1)
        return AVERROR_INVALIDDATA;
    sc = c->fc->streams[c->fc->nb_streams - 1]->priv_data;
    sc->timecode_track = avio_rb32(pb);
    return 0;
}

static int mov_read_vpcc(MOVContext *c, AVIOContext *pb, MOVAtom atom)
{
    AVStream *st;
    int version, color_range, color_primaries, color_trc, color_space;

    if (c->fc->nb_streams < 1)
        return 0;
    st = c->fc->streams[c->fc->nb_streams - 1];

    if (atom.size < 5) {
        av_log(c->fc, AV_LOG_ERROR, "Empty VP Codec Configuration box\n");
        return AVERROR_INVALIDDATA;
    }

    version = avio_r8(pb);
    if (version != 1) {
        av_log(c->fc, AV_LOG_WARNING, "Unsupported VP Codec Configuration box version %d\n", version);
        return 0;
    }
    avio_skip(pb, 3); /* flags */

    avio_skip(pb, 2); /* profile + level */
    color_range     = avio_r8(pb); /* bitDepth, chromaSubsampling, videoFullRangeFlag */
    color_primaries = avio_r8(pb);
    color_trc       = avio_r8(pb);
    color_space     = avio_r8(pb);
    if (avio_rb16(pb)) /* codecIntializationDataSize */
        return AVERROR_INVALIDDATA;

    if (!av_color_primaries_name(color_primaries))
        color_primaries = AVCOL_PRI_UNSPECIFIED;
    if (!av_color_transfer_name(color_trc))
        color_trc = AVCOL_TRC_UNSPECIFIED;
    if (!av_color_space_name(color_space))
        color_space = AVCOL_SPC_UNSPECIFIED;

    st->codecpar->color_range     = (color_range & 1) ? AVCOL_RANGE_JPEG : AVCOL_RANGE_MPEG;
    st->codecpar->color_primaries = color_primaries;
    st->codecpar->color_trc       = color_trc;
    st->codecpar->color_space     = color_space;

    return 0;
}

static int mov_read_smdm(MOVContext *c, AVIOContext *pb, MOVAtom atom)
{
    MOVStreamContext *sc;
    const int chroma_den = 50000;
    const int luma_den = 10000;
    int i, j, version;

    if (c->fc->nb_streams < 1)
        return AVERROR_INVALIDDATA;

    sc = c->fc->streams[c->fc->nb_streams - 1]->priv_data;

    if (atom.size < 5) {
        av_log(c->fc, AV_LOG_ERROR, "Empty Mastering Display Metadata box\n");
        return AVERROR_INVALIDDATA;
    }

    version = avio_r8(pb);
    if (version) {
        av_log(c->fc, AV_LOG_WARNING, "Unsupported Mastering Display Metadata box version %d\n", version);
        return 0;
    }
    avio_skip(pb, 3); /* flags */

    sc->mastering = av_mastering_display_metadata_alloc();
    if (!sc->mastering)
        return AVERROR(ENOMEM);

    for (i = 0; i < 3; i++)
        for (j = 0; j < 2; j++)
            sc->mastering->display_primaries[i][j] =
                av_make_q(lrint(((double)avio_rb16(pb) / (1 << 16)) * chroma_den), chroma_den);
    for (i = 0; i < 2; i++)
        sc->mastering->white_point[i] =
            av_make_q(lrint(((double)avio_rb16(pb) / (1 << 16)) * chroma_den), chroma_den);
    sc->mastering->max_luminance =
        av_make_q(lrint(((double)avio_rb32(pb) / (1 <<  8)) * luma_den), luma_den);
    sc->mastering->min_luminance =
        av_make_q(lrint(((double)avio_rb32(pb) / (1 << 14)) * luma_den), luma_den);

    sc->mastering->has_primaries = 1;
    sc->mastering->has_luminance = 1;

    return 0;
}

static int mov_read_mdcv(MOVContext *c, AVIOContext *pb, MOVAtom atom)
{
    MOVStreamContext *sc;
    const int mapping[3] = {1, 2, 0};
    const int chroma_den = 50000;
    const int luma_den = 10000;
    int i;

    if (c->fc->nb_streams < 1)
        return AVERROR_INVALIDDATA;

    sc = c->fc->streams[c->fc->nb_streams - 1]->priv_data;

    if (atom.size < 24) {
        av_log(c->fc, AV_LOG_ERROR, "Invalid Mastering Display Color Volume box\n");
        return AVERROR_INVALIDDATA;
    }

    sc->mastering = av_mastering_display_metadata_alloc();
    if (!sc->mastering)
        return AVERROR(ENOMEM);

    for (i = 0; i < 3; i++) {
        const int j = mapping[i];
        sc->mastering->display_primaries[j][0] = av_make_q(avio_rb16(pb), chroma_den);
        sc->mastering->display_primaries[j][1] = av_make_q(avio_rb16(pb), chroma_den);
    }
    sc->mastering->white_point[0] = av_make_q(avio_rb16(pb), chroma_den);
    sc->mastering->white_point[1] = av_make_q(avio_rb16(pb), chroma_den);

    sc->mastering->max_luminance = av_make_q(avio_rb32(pb), luma_den);
    sc->mastering->min_luminance = av_make_q(avio_rb32(pb), luma_den);

    sc->mastering->has_luminance = 1;
    sc->mastering->has_primaries = 1;

    return 0;
}

static int mov_read_coll(MOVContext *c, AVIOContext *pb, MOVAtom atom)
{
    MOVStreamContext *sc;
    int version;

    if (c->fc->nb_streams < 1)
        return AVERROR_INVALIDDATA;

    sc = c->fc->streams[c->fc->nb_streams - 1]->priv_data;

    if (atom.size < 5) {
        av_log(c->fc, AV_LOG_ERROR, "Empty Content Light Level box\n");
        return AVERROR_INVALIDDATA;
    }

    version = avio_r8(pb);
    if (version) {
        av_log(c->fc, AV_LOG_WARNING, "Unsupported Content Light Level box version %d\n", version);
        return 0;
    }
    avio_skip(pb, 3); /* flags */

    sc->coll = av_content_light_metadata_alloc(&sc->coll_size);
    if (!sc->coll)
        return AVERROR(ENOMEM);

    sc->coll->MaxCLL  = avio_rb16(pb);
    sc->coll->MaxFALL = avio_rb16(pb);

    return 0;
}

static int mov_read_clli(MOVContext *c, AVIOContext *pb, MOVAtom atom)
{
    MOVStreamContext *sc;

    if (c->fc->nb_streams < 1)
        return AVERROR_INVALIDDATA;

    sc = c->fc->streams[c->fc->nb_streams - 1]->priv_data;

    if (atom.size < 4) {
        av_log(c->fc, AV_LOG_ERROR, "Empty Content Light Level Info box\n");
        return AVERROR_INVALIDDATA;
    }

    sc->coll = av_content_light_metadata_alloc(&sc->coll_size);
    if (!sc->coll)
        return AVERROR(ENOMEM);

    sc->coll->MaxCLL  = avio_rb16(pb);
    sc->coll->MaxFALL = avio_rb16(pb);

    return 0;
}

static int mov_read_st3d(MOVContext *c, AVIOContext *pb, MOVAtom atom)
{
    AVStream *st;
    MOVStreamContext *sc;
    enum AVStereo3DType type;
    int mode;

    if (c->fc->nb_streams < 1)
        return 0;

    st = c->fc->streams[c->fc->nb_streams - 1];
    sc = st->priv_data;

    if (atom.size < 5) {
        av_log(c->fc, AV_LOG_ERROR, "Empty stereoscopic video box\n");
        return AVERROR_INVALIDDATA;
    }
    avio_skip(pb, 4); /* version + flags */

    mode = avio_r8(pb);
    switch (mode) {
    case 0:
        type = AV_STEREO3D_2D;
        break;
    case 1:
        type = AV_STEREO3D_TOPBOTTOM;
        break;
    case 2:
        type = AV_STEREO3D_SIDEBYSIDE;
        break;
    default:
        av_log(c->fc, AV_LOG_WARNING, "Unknown st3d mode value %d\n", mode);
        return 0;
    }

    sc->stereo3d = av_stereo3d_alloc();
    if (!sc->stereo3d)
        return AVERROR(ENOMEM);

    sc->stereo3d->type = type;
    return 0;
}

static int mov_read_sv3d(MOVContext *c, AVIOContext *pb, MOVAtom atom)
{
    AVStream *st;
    MOVStreamContext *sc;
    int size, version, layout;
    int32_t yaw, pitch, roll;
    uint32_t l = 0, t = 0, r = 0, b = 0;
    uint32_t tag, padding = 0;
    enum AVSphericalProjection projection;

    if (c->fc->nb_streams < 1)
        return 0;

    st = c->fc->streams[c->fc->nb_streams - 1];
    sc = st->priv_data;

    if (atom.size < 8) {
        av_log(c->fc, AV_LOG_ERROR, "Empty spherical video box\n");
        return AVERROR_INVALIDDATA;
    }

    size = avio_rb32(pb);
    if (size <= 12 || size > atom.size)
        return AVERROR_INVALIDDATA;

    tag = avio_rl32(pb);
    if (tag != MKTAG('s','v','h','d')) {
        av_log(c->fc, AV_LOG_ERROR, "Missing spherical video header\n");
        return 0;
    }
    version = avio_r8(pb);
    if (version != 0) {
        av_log(c->fc, AV_LOG_WARNING, "Unknown spherical version %d\n",
               version);
        return 0;
    }
    avio_skip(pb, 3); /* flags */
    avio_skip(pb, size - 12); /* metadata_source */

    size = avio_rb32(pb);
    if (size > atom.size)
        return AVERROR_INVALIDDATA;

    tag = avio_rl32(pb);
    if (tag != MKTAG('p','r','o','j')) {
        av_log(c->fc, AV_LOG_ERROR, "Missing projection box\n");
        return 0;
    }

    size = avio_rb32(pb);
    if (size > atom.size)
        return AVERROR_INVALIDDATA;

    tag = avio_rl32(pb);
    if (tag != MKTAG('p','r','h','d')) {
        av_log(c->fc, AV_LOG_ERROR, "Missing projection header box\n");
        return 0;
    }
    version = avio_r8(pb);
    if (version != 0) {
        av_log(c->fc, AV_LOG_WARNING, "Unknown spherical version %d\n",
               version);
        return 0;
    }
    avio_skip(pb, 3); /* flags */

    /* 16.16 fixed point */
    yaw   = avio_rb32(pb);
    pitch = avio_rb32(pb);
    roll  = avio_rb32(pb);

    size = avio_rb32(pb);
    if (size > atom.size)
        return AVERROR_INVALIDDATA;

    tag = avio_rl32(pb);
    version = avio_r8(pb);
    if (version != 0) {
        av_log(c->fc, AV_LOG_WARNING, "Unknown spherical version %d\n",
               version);
        return 0;
    }
    avio_skip(pb, 3); /* flags */
    switch (tag) {
    case MKTAG('c','b','m','p'):
        layout = avio_rb32(pb);
        if (layout) {
            av_log(c->fc, AV_LOG_WARNING,
                   "Unsupported cubemap layout %d\n", layout);
            return 0;
        }
        projection = AV_SPHERICAL_CUBEMAP;
        padding = avio_rb32(pb);
        break;
    case MKTAG('e','q','u','i'):
        t = avio_rb32(pb);
        b = avio_rb32(pb);
        l = avio_rb32(pb);
        r = avio_rb32(pb);

        if (b >= UINT_MAX - t || r >= UINT_MAX - l) {
            av_log(c->fc, AV_LOG_ERROR,
                   "Invalid bounding rectangle coordinates "
                   "%"PRIu32",%"PRIu32",%"PRIu32",%"PRIu32"\n", l, t, r, b);
            return AVERROR_INVALIDDATA;
        }

        if (l || t || r || b)
            projection = AV_SPHERICAL_EQUIRECTANGULAR_TILE;
        else
            projection = AV_SPHERICAL_EQUIRECTANGULAR;
        break;
    default:
        av_log(c->fc, AV_LOG_ERROR, "Unknown projection type: %s\n", av_fourcc2str(tag));
        return 0;
    }

    sc->spherical = av_spherical_alloc(&sc->spherical_size);
    if (!sc->spherical)
        return AVERROR(ENOMEM);

    sc->spherical->projection = projection;

    sc->spherical->yaw   = yaw;
    sc->spherical->pitch = pitch;
    sc->spherical->roll  = roll;

    sc->spherical->padding = padding;

    sc->spherical->bound_left   = l;
    sc->spherical->bound_top    = t;
    sc->spherical->bound_right  = r;
    sc->spherical->bound_bottom = b;

    return 0;
}

static int mov_parse_uuid_spherical(MOVStreamContext *sc, AVIOContext *pb, size_t len)
{
    int ret = 0;
    uint8_t *buffer = av_malloc(len + 1);
    const char *val;

    if (!buffer)
        return AVERROR(ENOMEM);
    buffer[len] = '\0';

    ret = ffio_read_size(pb, buffer, len);
    if (ret < 0)
        goto out;

    /* Check for mandatory keys and values, try to support XML as best-effort */
    if (!sc->spherical &&
        av_stristr(buffer, "<GSpherical:StitchingSoftware>") &&
        (val = av_stristr(buffer, "<GSpherical:Spherical>")) &&
        av_stristr(val, "true") &&
        (val = av_stristr(buffer, "<GSpherical:Stitched>")) &&
        av_stristr(val, "true") &&
        (val = av_stristr(buffer, "<GSpherical:ProjectionType>")) &&
        av_stristr(val, "equirectangular")) {
        sc->spherical = av_spherical_alloc(&sc->spherical_size);
        if (!sc->spherical)
            goto out;

        sc->spherical->projection = AV_SPHERICAL_EQUIRECTANGULAR;

        if (av_stristr(buffer, "<GSpherical:StereoMode>") && !sc->stereo3d) {
            enum AVStereo3DType mode;

            if (av_stristr(buffer, "left-right"))
                mode = AV_STEREO3D_SIDEBYSIDE;
            else if (av_stristr(buffer, "top-bottom"))
                mode = AV_STEREO3D_TOPBOTTOM;
            else
                mode = AV_STEREO3D_2D;

            sc->stereo3d = av_stereo3d_alloc();
            if (!sc->stereo3d)
                goto out;

            sc->stereo3d->type = mode;
        }

        /* orientation */
        val = av_stristr(buffer, "<GSpherical:InitialViewHeadingDegrees>");
        if (val)
            sc->spherical->yaw = strtol(val, NULL, 10) * (1 << 16);
        val = av_stristr(buffer, "<GSpherical:InitialViewPitchDegrees>");
        if (val)
            sc->spherical->pitch = strtol(val, NULL, 10) * (1 << 16);
        val = av_stristr(buffer, "<GSpherical:InitialViewRollDegrees>");
        if (val)
            sc->spherical->roll = strtol(val, NULL, 10) * (1 << 16);
    }

out:
    av_free(buffer);
    return ret;
}

static int mov_read_uuid(MOVContext *c, AVIOContext *pb, MOVAtom atom)
{
    AVStream *st;
    MOVStreamContext *sc;
    int64_t ret;
    uint8_t uuid[16];
    static const uint8_t uuid_isml_manifest[] = {
        0xa5, 0xd4, 0x0b, 0x30, 0xe8, 0x14, 0x11, 0xdd,
        0xba, 0x2f, 0x08, 0x00, 0x20, 0x0c, 0x9a, 0x66
    };
    static const uint8_t uuid_xmp[] = {
        0xbe, 0x7a, 0xcf, 0xcb, 0x97, 0xa9, 0x42, 0xe8,
        0x9c, 0x71, 0x99, 0x94, 0x91, 0xe3, 0xaf, 0xac
    };
    static const uint8_t uuid_spherical[] = {
        0xff, 0xcc, 0x82, 0x63, 0xf8, 0x55, 0x4a, 0x93,
        0x88, 0x14, 0x58, 0x7a, 0x02, 0x52, 0x1f, 0xdd,
    };

    if (atom.size < sizeof(uuid) || atom.size >= FFMIN(INT_MAX, SIZE_MAX))
        return AVERROR_INVALIDDATA;

    if (c->fc->nb_streams < 1)
        return 0;
    st = c->fc->streams[c->fc->nb_streams - 1];
    sc = st->priv_data;

    ret = avio_read(pb, uuid, sizeof(uuid));
    if (ret < 0) {
        return ret;
    } else if (ret != sizeof(uuid)) {
        return AVERROR_INVALIDDATA;
    }
    if (!memcmp(uuid, uuid_isml_manifest, sizeof(uuid))) {
        uint8_t *buffer, *ptr;
        char *endptr;
        size_t len = atom.size - sizeof(uuid);

        if (len < 4) {
            return AVERROR_INVALIDDATA;
        }
        ret = avio_skip(pb, 4); // zeroes
        len -= 4;

        buffer = av_mallocz(len + 1);
        if (!buffer) {
            return AVERROR(ENOMEM);
        }
        ret = avio_read(pb, buffer, len);
        if (ret < 0) {
            av_free(buffer);
            return ret;
        } else if (ret != len) {
            av_free(buffer);
            return AVERROR_INVALIDDATA;
        }

        ptr = buffer;
        while ((ptr = av_stristr(ptr, "systemBitrate=\""))) {
            ptr += sizeof("systemBitrate=\"") - 1;
            c->bitrates_count++;
            c->bitrates = av_realloc_f(c->bitrates, c->bitrates_count, sizeof(*c->bitrates));
            if (!c->bitrates) {
                c->bitrates_count = 0;
                av_free(buffer);
                return AVERROR(ENOMEM);
            }
            errno = 0;
            ret = strtol(ptr, &endptr, 10);
            if (ret < 0 || errno || *endptr != '"') {
                c->bitrates[c->bitrates_count - 1] = 0;
            } else {
                c->bitrates[c->bitrates_count - 1] = ret;
            }
        }

        av_free(buffer);
    } else if (!memcmp(uuid, uuid_xmp, sizeof(uuid))) {
        uint8_t *buffer;
        size_t len = atom.size - sizeof(uuid);
        if (c->export_xmp) {
            buffer = av_mallocz(len + 1);
            if (!buffer) {
                return AVERROR(ENOMEM);
            }
            ret = avio_read(pb, buffer, len);
            if (ret < 0) {
                av_free(buffer);
                return ret;
            } else if (ret != len) {
                av_free(buffer);
                return AVERROR_INVALIDDATA;
            }
            buffer[len] = '\0';
            av_dict_set(&c->fc->metadata, "xmp", buffer, 0);
            av_free(buffer);
        } else {
            // skip all uuid atom, which makes it fast for long uuid-xmp file
            ret = avio_skip(pb, len);
            if (ret < 0)
                return ret;
        }
    } else if (!memcmp(uuid, uuid_spherical, sizeof(uuid))) {
        size_t len = atom.size - sizeof(uuid);
        ret = mov_parse_uuid_spherical(sc, pb, len);
        if (ret < 0)
            return ret;
        if (!sc->spherical)
            av_log(c->fc, AV_LOG_WARNING, "Invalid spherical metadata found\n");
    }

    return 0;
}

static int mov_read_free(MOVContext *c, AVIOContext *pb, MOVAtom atom)
{
    int ret;
    uint8_t content[16];

    if (atom.size < 8)
        return 0;

    ret = avio_read(pb, content, FFMIN(sizeof(content), atom.size));
    if (ret < 0)
        return ret;

    if (   !c->found_moov
        && !c->found_mdat
        && !memcmp(content, "Anevia\x1A\x1A", 8)
        && c->use_mfra_for == FF_MOV_FLAG_MFRA_AUTO) {
        c->use_mfra_for = FF_MOV_FLAG_MFRA_PTS;
    }

    return 0;
}

static int mov_read_frma(MOVContext *c, AVIOContext *pb, MOVAtom atom)
{
    uint32_t format = avio_rl32(pb);
    MOVStreamContext *sc;
    enum AVCodecID id;
    AVStream *st;

    if (c->fc->nb_streams < 1)
        return 0;
    st = c->fc->streams[c->fc->nb_streams - 1];
    sc = st->priv_data;

    switch (sc->format)
    {
    case MKTAG('e','n','c','v'):        // encrypted video
    case MKTAG('e','n','c','a'):        // encrypted audio
        id = mov_codec_id(st, format);
        if (st->codecpar->codec_id != AV_CODEC_ID_NONE &&
            st->codecpar->codec_id != id) {
            av_log(c->fc, AV_LOG_WARNING,
                   "ignoring 'frma' atom of '%.4s', stream has codec id %d\n",
                   (char*)&format, st->codecpar->codec_id);
            break;
        }

        st->codecpar->codec_id = id;
        sc->format = format;
        break;

    default:
        if (format != sc->format) {
            av_log(c->fc, AV_LOG_WARNING,
                   "ignoring 'frma' atom of '%.4s', stream format is '%.4s'\n",
                   (char*)&format, (char*)&sc->format);
        }
        break;
    }

    return 0;
}

static int mov_read_senc(MOVContext *c, AVIOContext *pb, MOVAtom atom)
{
    AVStream *st;
    MOVStreamContext *sc;
    size_t auxiliary_info_size;

    if (c->decryption_key_len == 0 || c->fc->nb_streams < 1)
        return 0;

    st = c->fc->streams[c->fc->nb_streams - 1];
    sc = st->priv_data;

    if (sc->cenc.aes_ctr) {
        av_log(c->fc, AV_LOG_ERROR, "duplicate senc atom\n");
        return AVERROR_INVALIDDATA;
    }

    avio_r8(pb); /* version */
    sc->cenc.use_subsamples = avio_rb24(pb) & 0x02; /* flags */

    avio_rb32(pb);        /* entries */

    if (atom.size < 8 || atom.size > FFMIN(INT_MAX, SIZE_MAX)) {
        av_log(c->fc, AV_LOG_ERROR, "senc atom size %"PRId64" invalid\n", atom.size);
        return AVERROR_INVALIDDATA;
    }

    /* save the auxiliary info as is */
    auxiliary_info_size = atom.size - 8;

    sc->cenc.auxiliary_info = av_malloc(auxiliary_info_size);
    if (!sc->cenc.auxiliary_info) {
        return AVERROR(ENOMEM);
    }

    sc->cenc.auxiliary_info_end = sc->cenc.auxiliary_info + auxiliary_info_size;
    sc->cenc.auxiliary_info_pos = sc->cenc.auxiliary_info;
    sc->cenc.auxiliary_info_index = 0;

    if (avio_read(pb, sc->cenc.auxiliary_info, auxiliary_info_size) != auxiliary_info_size) {
        av_log(c->fc, AV_LOG_ERROR, "failed to read the auxiliary info");
        return AVERROR_INVALIDDATA;
    }

    /* initialize the cipher */
    sc->cenc.aes_ctr = av_aes_ctr_alloc();
    if (!sc->cenc.aes_ctr) {
        return AVERROR(ENOMEM);
    }

    return av_aes_ctr_init(sc->cenc.aes_ctr, c->decryption_key);
}

static int mov_read_saiz(MOVContext *c, AVIOContext *pb, MOVAtom atom)
{
    AVStream *st;
    MOVStreamContext *sc;
    size_t data_size;
    int atom_header_size;
    int flags;

    if (c->decryption_key_len == 0 || c->fc->nb_streams < 1)
        return 0;

    st = c->fc->streams[c->fc->nb_streams - 1];
    sc = st->priv_data;

    if (sc->cenc.auxiliary_info_sizes || sc->cenc.auxiliary_info_default_size) {
        av_log(c->fc, AV_LOG_ERROR, "duplicate saiz atom\n");
        return AVERROR_INVALIDDATA;
    }

    atom_header_size = 9;

    avio_r8(pb); /* version */
    flags = avio_rb24(pb);

    if ((flags & 0x01) != 0) {
        atom_header_size += 8;

        avio_rb32(pb);    /* info type */
        avio_rb32(pb);    /* info type param */
    }

    sc->cenc.auxiliary_info_default_size = avio_r8(pb);
    avio_rb32(pb);    /* entries */

    if (atom.size <= atom_header_size) {
        return 0;
    }

    if (atom.size > FFMIN(INT_MAX, SIZE_MAX)) {
        av_log(c->fc, AV_LOG_ERROR, "saiz atom auxiliary_info_sizes size %"PRId64" invalid\n", atom.size);
        return AVERROR_INVALIDDATA;
    }

    /* save the auxiliary info sizes as is */
    data_size = atom.size - atom_header_size;

    sc->cenc.auxiliary_info_sizes = av_malloc(data_size);
    if (!sc->cenc.auxiliary_info_sizes) {
        return AVERROR(ENOMEM);
    }

    sc->cenc.auxiliary_info_sizes_count = data_size;

    if (avio_read(pb, sc->cenc.auxiliary_info_sizes, data_size) != data_size) {
        av_log(c->fc, AV_LOG_ERROR, "failed to read the auxiliary info sizes");
        return AVERROR_INVALIDDATA;
    }

    return 0;
}

static int mov_read_dfla(MOVContext *c, AVIOContext *pb, MOVAtom atom)
{
    AVStream *st;
    int last, type, size, ret;
    uint8_t buf[4];

    if (c->fc->nb_streams < 1)
        return 0;
    st = c->fc->streams[c->fc->nb_streams-1];

    if ((uint64_t)atom.size > (1<<30) || atom.size < 42)
        return AVERROR_INVALIDDATA;

    /* Check FlacSpecificBox version. */
    if (avio_r8(pb) != 0)
        return AVERROR_INVALIDDATA;

    avio_rb24(pb); /* Flags */

    avio_read(pb, buf, sizeof(buf));
    flac_parse_block_header(buf, &last, &type, &size);

    if (type != FLAC_METADATA_TYPE_STREAMINFO || size != FLAC_STREAMINFO_SIZE) {
        av_log(c->fc, AV_LOG_ERROR, "STREAMINFO must be first FLACMetadataBlock\n");
        return AVERROR_INVALIDDATA;
    }

    ret = ff_get_extradata(c->fc, st->codecpar, pb, size);
    if (ret < 0)
        return ret;

    if (!last)
        av_log(c->fc, AV_LOG_WARNING, "non-STREAMINFO FLACMetadataBlock(s) ignored\n");

    return 0;
}

static int mov_seek_auxiliary_info(MOVContext *c, MOVStreamContext *sc, int64_t index)
{
    size_t auxiliary_info_seek_offset = 0;
    int i;

    if (sc->cenc.auxiliary_info_default_size) {
        auxiliary_info_seek_offset = (size_t)sc->cenc.auxiliary_info_default_size * index;
    } else if (sc->cenc.auxiliary_info_sizes) {
        if (index > sc->cenc.auxiliary_info_sizes_count) {
            av_log(c, AV_LOG_ERROR, "current sample %"PRId64" greater than the number of auxiliary info sample sizes %"SIZE_SPECIFIER"\n",
                index, sc->cenc.auxiliary_info_sizes_count);
            return AVERROR_INVALIDDATA;
        }

        for (i = 0; i < index; i++) {
            auxiliary_info_seek_offset += sc->cenc.auxiliary_info_sizes[i];
        }
    }

    if (auxiliary_info_seek_offset > sc->cenc.auxiliary_info_end - sc->cenc.auxiliary_info) {
        av_log(c, AV_LOG_ERROR, "auxiliary info offset %"SIZE_SPECIFIER" greater than auxiliary info size %"SIZE_SPECIFIER"\n",
            auxiliary_info_seek_offset, (size_t)(sc->cenc.auxiliary_info_end - sc->cenc.auxiliary_info));
        return AVERROR_INVALIDDATA;
    }

    sc->cenc.auxiliary_info_pos = sc->cenc.auxiliary_info + auxiliary_info_seek_offset;
    sc->cenc.auxiliary_info_index = index;
    return 0;
}

static int cenc_filter(MOVContext *c, MOVStreamContext *sc, int64_t index, uint8_t *input, int size)
{
    uint32_t encrypted_bytes;
    uint16_t subsample_count;
    uint16_t clear_bytes;
    uint8_t* input_end = input + size;
    int ret;

    if (index != sc->cenc.auxiliary_info_index) {
        ret = mov_seek_auxiliary_info(c, sc, index);
        if (ret < 0) {
            return ret;
        }
    }

    /* read the iv */
    if (AES_CTR_IV_SIZE > sc->cenc.auxiliary_info_end - sc->cenc.auxiliary_info_pos) {
        av_log(c->fc, AV_LOG_ERROR, "failed to read iv from the auxiliary info\n");
        return AVERROR_INVALIDDATA;
    }

    av_aes_ctr_set_iv(sc->cenc.aes_ctr, sc->cenc.auxiliary_info_pos);
    sc->cenc.auxiliary_info_pos += AES_CTR_IV_SIZE;

    if (!sc->cenc.use_subsamples)
    {
        /* decrypt the whole packet */
        av_aes_ctr_crypt(sc->cenc.aes_ctr, input, input, size);
        return 0;
    }

    /* read the subsample count */
    if (sizeof(uint16_t) > sc->cenc.auxiliary_info_end - sc->cenc.auxiliary_info_pos) {
        av_log(c->fc, AV_LOG_ERROR, "failed to read subsample count from the auxiliary info\n");
        return AVERROR_INVALIDDATA;
    }

    subsample_count = AV_RB16(sc->cenc.auxiliary_info_pos);
    sc->cenc.auxiliary_info_pos += sizeof(uint16_t);

    for (; subsample_count > 0; subsample_count--)
    {
        if (6 > sc->cenc.auxiliary_info_end - sc->cenc.auxiliary_info_pos) {
            av_log(c->fc, AV_LOG_ERROR, "failed to read subsample from the auxiliary info\n");
            return AVERROR_INVALIDDATA;
        }

        /* read the number of clear / encrypted bytes */
        clear_bytes = AV_RB16(sc->cenc.auxiliary_info_pos);
        sc->cenc.auxiliary_info_pos += sizeof(uint16_t);
        encrypted_bytes = AV_RB32(sc->cenc.auxiliary_info_pos);
        sc->cenc.auxiliary_info_pos += sizeof(uint32_t);

        if ((uint64_t)clear_bytes + encrypted_bytes > input_end - input) {
            av_log(c->fc, AV_LOG_ERROR, "subsample size exceeds the packet size left\n");
            return AVERROR_INVALIDDATA;
        }

        /* skip the clear bytes */
        input += clear_bytes;

        /* decrypt the encrypted bytes */
        av_aes_ctr_crypt(sc->cenc.aes_ctr, input, input, encrypted_bytes);
        input += encrypted_bytes;
    }

    if (input < input_end) {
        av_log(c->fc, AV_LOG_ERROR, "leftover packet bytes after subsample processing\n");
        return AVERROR_INVALIDDATA;
    }

    sc->cenc.auxiliary_info_index++;
    return 0;
}

static int mov_read_dops(MOVContext *c, AVIOContext *pb, MOVAtom atom)
{
    const int OPUS_SEEK_PREROLL_MS = 80;
    AVStream *st;
    size_t size;
    int16_t pre_skip;

    if (c->fc->nb_streams < 1)
        return 0;
    st = c->fc->streams[c->fc->nb_streams-1];

    if ((uint64_t)atom.size > (1<<30) || atom.size < 11)
        return AVERROR_INVALIDDATA;

    /* Check OpusSpecificBox version. */
    if (avio_r8(pb) != 0) {
        av_log(c->fc, AV_LOG_ERROR, "unsupported OpusSpecificBox version\n");
        return AVERROR_INVALIDDATA;
    }

    /* OpusSpecificBox size plus magic for Ogg OpusHead header. */
    size = atom.size + 8;

    if (ff_alloc_extradata(st->codecpar, size))
        return AVERROR(ENOMEM);

    AV_WL32(st->codecpar->extradata, MKTAG('O','p','u','s'));
    AV_WL32(st->codecpar->extradata + 4, MKTAG('H','e','a','d'));
    AV_WB8(st->codecpar->extradata + 8, 1); /* OpusHead version */
    avio_read(pb, st->codecpar->extradata + 9, size - 9);

    /* OpusSpecificBox is stored in big-endian, but OpusHead is
       little-endian; aside from the preceeding magic and version they're
       otherwise currently identical.  Data after output gain at offset 16
       doesn't need to be bytewapped. */
    pre_skip = AV_RB16(st->codecpar->extradata + 10);
    AV_WL16(st->codecpar->extradata + 10, pre_skip);
    AV_WL32(st->codecpar->extradata + 12, AV_RB32(st->codecpar->extradata + 12));
    AV_WL16(st->codecpar->extradata + 16, AV_RB16(st->codecpar->extradata + 16));

    st->codecpar->initial_padding = pre_skip;
    st->codecpar->seek_preroll = av_rescale_q(OPUS_SEEK_PREROLL_MS,
                                              (AVRational){1, 1000},
                                              (AVRational){1, 48000});

    return 0;
}

static const MOVParseTableEntry mov_default_parse_table[] = {
{ MKTAG('A','C','L','R'), mov_read_aclr },
{ MKTAG('A','P','R','G'), mov_read_avid },
{ MKTAG('A','A','L','P'), mov_read_avid },
{ MKTAG('A','R','E','S'), mov_read_ares },
{ MKTAG('a','v','s','s'), mov_read_avss },
{ MKTAG('c','h','p','l'), mov_read_chpl },
{ MKTAG('c','o','6','4'), mov_read_stco },
{ MKTAG('c','o','l','r'), mov_read_colr },
{ MKTAG('c','t','t','s'), mov_read_ctts }, /* composition time to sample */
{ MKTAG('d','i','n','f'), mov_read_default },
{ MKTAG('D','p','x','E'), mov_read_dpxe },
{ MKTAG('d','r','e','f'), mov_read_dref },
{ MKTAG('e','d','t','s'), mov_read_default },
{ MKTAG('e','l','s','t'), mov_read_elst },
{ MKTAG('e','n','d','a'), mov_read_enda },
{ MKTAG('f','i','e','l'), mov_read_fiel },
{ MKTAG('a','d','r','m'), mov_read_adrm },
{ MKTAG('f','t','y','p'), mov_read_ftyp },
{ MKTAG('g','l','b','l'), mov_read_glbl },
{ MKTAG('h','d','l','r'), mov_read_hdlr },
{ MKTAG('i','l','s','t'), mov_read_ilst },
{ MKTAG('j','p','2','h'), mov_read_jp2h },
{ MKTAG('m','d','a','t'), mov_read_mdat },
{ MKTAG('m','d','h','d'), mov_read_mdhd },
{ MKTAG('m','d','i','a'), mov_read_default },
{ MKTAG('m','e','t','a'), mov_read_meta },
{ MKTAG('m','i','n','f'), mov_read_default },
{ MKTAG('m','o','o','f'), mov_read_moof },
{ MKTAG('m','o','o','v'), mov_read_moov },
{ MKTAG('m','v','e','x'), mov_read_default },
{ MKTAG('m','v','h','d'), mov_read_mvhd },
{ MKTAG('S','M','I',' '), mov_read_svq3 },
{ MKTAG('a','l','a','c'), mov_read_alac }, /* alac specific atom */
{ MKTAG('a','v','c','C'), mov_read_glbl },
{ MKTAG('p','a','s','p'), mov_read_pasp },
{ MKTAG('s','i','d','x'), mov_read_sidx },
{ MKTAG('s','t','b','l'), mov_read_default },
{ MKTAG('s','t','c','o'), mov_read_stco },
{ MKTAG('s','t','p','s'), mov_read_stps },
{ MKTAG('s','t','r','f'), mov_read_strf },
{ MKTAG('s','t','s','c'), mov_read_stsc },
{ MKTAG('s','t','s','d'), mov_read_stsd }, /* sample description */
{ MKTAG('s','t','s','s'), mov_read_stss }, /* sync sample */
{ MKTAG('s','t','s','z'), mov_read_stsz }, /* sample size */
{ MKTAG('s','t','t','s'), mov_read_stts },
{ MKTAG('s','t','z','2'), mov_read_stsz }, /* compact sample size */
{ MKTAG('t','k','h','d'), mov_read_tkhd }, /* track header */
{ MKTAG('t','f','d','t'), mov_read_tfdt },
{ MKTAG('t','f','h','d'), mov_read_tfhd }, /* track fragment header */
{ MKTAG('t','r','a','k'), mov_read_trak },
{ MKTAG('t','r','a','f'), mov_read_default },
{ MKTAG('t','r','e','f'), mov_read_default },
{ MKTAG('t','m','c','d'), mov_read_tmcd },
{ MKTAG('c','h','a','p'), mov_read_chap },
{ MKTAG('t','r','e','x'), mov_read_trex },
{ MKTAG('t','r','u','n'), mov_read_trun },
{ MKTAG('u','d','t','a'), mov_read_default },
{ MKTAG('w','a','v','e'), mov_read_wave },
{ MKTAG('e','s','d','s'), mov_read_esds },
{ MKTAG('d','a','c','3'), mov_read_dac3 }, /* AC-3 info */
{ MKTAG('d','e','c','3'), mov_read_dec3 }, /* EAC-3 info */
{ MKTAG('d','d','t','s'), mov_read_ddts }, /* DTS audio descriptor */
{ MKTAG('w','i','d','e'), mov_read_wide }, /* place holder */
{ MKTAG('w','f','e','x'), mov_read_wfex },
{ MKTAG('c','m','o','v'), mov_read_cmov },
{ MKTAG('c','h','a','n'), mov_read_chan }, /* channel layout */
{ MKTAG('d','v','c','1'), mov_read_dvc1 },
{ MKTAG('s','b','g','p'), mov_read_sbgp },
{ MKTAG('h','v','c','C'), mov_read_glbl },
{ MKTAG('u','u','i','d'), mov_read_uuid },
{ MKTAG('C','i','n', 0x8e), mov_read_targa_y216 },
{ MKTAG('f','r','e','e'), mov_read_free },
{ MKTAG('-','-','-','-'), mov_read_custom },
{ MKTAG('s','i','n','f'), mov_read_default },
{ MKTAG('f','r','m','a'), mov_read_frma },
{ MKTAG('s','e','n','c'), mov_read_senc },
{ MKTAG('s','a','i','z'), mov_read_saiz },
{ MKTAG('d','f','L','a'), mov_read_dfla },
{ MKTAG('s','t','3','d'), mov_read_st3d }, /* stereoscopic 3D video box */
{ MKTAG('s','v','3','d'), mov_read_sv3d }, /* spherical video box */
{ MKTAG('d','O','p','s'), mov_read_dops },
{ MKTAG('S','m','D','m'), mov_read_smdm },
{ MKTAG('C','o','L','L'), mov_read_coll },
{ MKTAG('v','p','c','C'), mov_read_vpcc },
{ MKTAG('m','d','c','v'), mov_read_mdcv },
{ MKTAG('c','l','l','i'), mov_read_clli },
{ 0, NULL }
};

static int mov_read_default(MOVContext *c, AVIOContext *pb, MOVAtom atom)
{
    int64_t total_size = 0;
    MOVAtom a;
    int i;

    if (c->atom_depth > 10) {
        av_log(c->fc, AV_LOG_ERROR, "Atoms too deeply nested\n");
        return AVERROR_INVALIDDATA;
    }
    c->atom_depth ++;

    if (atom.size < 0)
        atom.size = INT64_MAX;
    while (total_size <= atom.size - 8 && !avio_feof(pb)) {
        int (*parse)(MOVContext*, AVIOContext*, MOVAtom) = NULL;
        a.size = atom.size;
        a.type=0;
        if (atom.size >= 8) {
            a.size = avio_rb32(pb);
            a.type = avio_rl32(pb);
            if (a.type == MKTAG('f','r','e','e') &&
                a.size >= 8 &&
                c->fc->strict_std_compliance < FF_COMPLIANCE_STRICT &&
                c->moov_retry) {
                uint8_t buf[8];
                uint32_t *type = (uint32_t *)buf + 1;
                if (avio_read(pb, buf, 8) != 8)
                    return AVERROR_INVALIDDATA;
                avio_seek(pb, -8, SEEK_CUR);
                if (*type == MKTAG('m','v','h','d') ||
                    *type == MKTAG('c','m','o','v')) {
                    av_log(c->fc, AV_LOG_ERROR, "Detected moov in a free atom.\n");
                    a.type = MKTAG('m','o','o','v');
                }
            }
            if (atom.type != MKTAG('r','o','o','t') &&
                atom.type != MKTAG('m','o','o','v'))
            {
                if (a.type == MKTAG('t','r','a','k') || a.type == MKTAG('m','d','a','t'))
                {
                    av_log(c->fc, AV_LOG_ERROR, "Broken file, trak/mdat not at top-level\n");
                    avio_skip(pb, -8);
                    c->atom_depth --;
                    return 0;
                }
            }
            total_size += 8;
            if (a.size == 1 && total_size + 8 <= atom.size) { /* 64 bit extended size */
                a.size = avio_rb64(pb) - 8;
                total_size += 8;
            }
        }
        av_log(c->fc, AV_LOG_TRACE, "type:'%s' parent:'%s' sz: %"PRId64" %"PRId64" %"PRId64"\n",
               av_fourcc2str(a.type), av_fourcc2str(atom.type), a.size, total_size, atom.size);
        if (a.size == 0) {
            a.size = atom.size - total_size + 8;
        }
        a.size -= 8;
        if (a.size < 0)
            break;
        a.size = FFMIN(a.size, atom.size - total_size);

        for (i = 0; mov_default_parse_table[i].type; i++)
            if (mov_default_parse_table[i].type == a.type) {
                parse = mov_default_parse_table[i].parse;
                break;
            }

        // container is user data
        if (!parse && (atom.type == MKTAG('u','d','t','a') ||
                       atom.type == MKTAG('i','l','s','t')))
            parse = mov_read_udta_string;

        // Supports parsing the QuickTime Metadata Keys.
        // https://developer.apple.com/library/mac/documentation/QuickTime/QTFF/Metadata/Metadata.html
        if (!parse && c->found_hdlr_mdta &&
            atom.type == MKTAG('m','e','t','a') &&
            a.type == MKTAG('k','e','y','s')) {
            parse = mov_read_keys;
        }

        if (!parse) { /* skip leaf atoms data */
            avio_skip(pb, a.size);
        } else {
            int64_t start_pos = avio_tell(pb);
            int64_t left;
            int err = parse(c, pb, a);
            if (err < 0) {
                c->atom_depth --;
                return err;
            }
            if (c->found_moov && c->found_mdat &&
                ((!(pb->seekable & AVIO_SEEKABLE_NORMAL) || c->fc->flags & AVFMT_FLAG_IGNIDX || c->frag_index.complete) ||
                 start_pos + a.size == avio_size(pb))) {
                if (!(pb->seekable & AVIO_SEEKABLE_NORMAL) || c->fc->flags & AVFMT_FLAG_IGNIDX || c->frag_index.complete)
                    c->next_root_atom = start_pos + a.size;
                c->atom_depth --;
                return 0;
            }
            left = a.size - avio_tell(pb) + start_pos;
            if (left > 0) /* skip garbage at atom end */
                avio_skip(pb, left);
            else if (left < 0) {
                av_log(c->fc, AV_LOG_WARNING,
                       "overread end of atom '%.4s' by %"PRId64" bytes\n",
                       (char*)&a.type, -left);
                avio_seek(pb, left, SEEK_CUR);
            }
        }

        total_size += a.size;
    }

    if (total_size < atom.size && atom.size < 0x7ffff)
        avio_skip(pb, atom.size - total_size);

    c->atom_depth --;
    return 0;
}

static int mov_probe(AVProbeData *p)
{
    int64_t offset;
    uint32_t tag;
    int score = 0;
    int moov_offset = -1;

    /* check file header */
    offset = 0;
    for (;;) {
        /* ignore invalid offset */
        if ((offset + 8) > (unsigned int)p->buf_size)
            break;
        tag = AV_RL32(p->buf + offset + 4);
        switch(tag) {
        /* check for obvious tags */
        case MKTAG('m','o','o','v'):
            moov_offset = offset + 4;
        case MKTAG('m','d','a','t'):
        case MKTAG('p','n','o','t'): /* detect movs with preview pics like ew.mov and april.mov */
        case MKTAG('u','d','t','a'): /* Packet Video PVAuthor adds this and a lot of more junk */
        case MKTAG('f','t','y','p'):
            if (AV_RB32(p->buf+offset) < 8 &&
                (AV_RB32(p->buf+offset) != 1 ||
                 offset + 12 > (unsigned int)p->buf_size ||
                 AV_RB64(p->buf+offset + 8) == 0)) {
                score = FFMAX(score, AVPROBE_SCORE_EXTENSION);
            } else if (tag == MKTAG('f','t','y','p') &&
                       (   AV_RL32(p->buf + offset + 8) == MKTAG('j','p','2',' ')
                        || AV_RL32(p->buf + offset + 8) == MKTAG('j','p','x',' ')
                    )) {
                score = FFMAX(score, 5);
            } else {
                score = AVPROBE_SCORE_MAX;
            }
            offset = FFMAX(4, AV_RB32(p->buf+offset)) + offset;
            break;
        /* those are more common words, so rate then a bit less */
        case MKTAG('e','d','i','w'): /* xdcam files have reverted first tags */
        case MKTAG('w','i','d','e'):
        case MKTAG('f','r','e','e'):
        case MKTAG('j','u','n','k'):
        case MKTAG('p','i','c','t'):
            score  = FFMAX(score, AVPROBE_SCORE_MAX - 5);
            offset = FFMAX(4, AV_RB32(p->buf+offset)) + offset;
            break;
        case MKTAG(0x82,0x82,0x7f,0x7d):
        case MKTAG('s','k','i','p'):
        case MKTAG('u','u','i','d'):
        case MKTAG('p','r','f','l'):
            /* if we only find those cause probedata is too small at least rate them */
            score  = FFMAX(score, AVPROBE_SCORE_EXTENSION);
            offset = FFMAX(4, AV_RB32(p->buf+offset)) + offset;
            break;
        default:
            offset = FFMAX(4, AV_RB32(p->buf+offset)) + offset;
        }
    }
    if(score > AVPROBE_SCORE_MAX - 50 && moov_offset != -1) {
        /* moov atom in the header - we should make sure that this is not a
         * MOV-packed MPEG-PS */
        offset = moov_offset;

        while(offset < (p->buf_size - 16)){ /* Sufficient space */
               /* We found an actual hdlr atom */
            if(AV_RL32(p->buf + offset     ) == MKTAG('h','d','l','r') &&
               AV_RL32(p->buf + offset +  8) == MKTAG('m','h','l','r') &&
               AV_RL32(p->buf + offset + 12) == MKTAG('M','P','E','G')){
                av_log(NULL, AV_LOG_WARNING, "Found media data tag MPEG indicating this is a MOV-packed MPEG-PS.\n");
                /* We found a media handler reference atom describing an
                 * MPEG-PS-in-MOV, return a
                 * low score to force expanding the probe window until
                 * mpegps_probe finds what it needs */
                return 5;
            }else
                /* Keep looking */
                offset+=2;
        }
    }

    return score;
}

// must be done after parsing all trak because there's no order requirement
static void mov_read_chapters(AVFormatContext *s)
{
    MOVContext *mov = s->priv_data;
    AVStream *st;
    MOVStreamContext *sc;
    int64_t cur_pos;
    int i, j;
    int chapter_track;

    for (j = 0; j < mov->nb_chapter_tracks; j++) {
        chapter_track = mov->chapter_tracks[j];
        st = NULL;
        for (i = 0; i < s->nb_streams; i++)
            if (s->streams[i]->id == chapter_track) {
                st = s->streams[i];
                break;
            }
        if (!st) {
            av_log(s, AV_LOG_ERROR, "Referenced QT chapter track not found\n");
            continue;
        }

        sc = st->priv_data;
        cur_pos = avio_tell(sc->pb);

        if (st->codecpar->codec_type == AVMEDIA_TYPE_VIDEO) {
            st->disposition |= AV_DISPOSITION_ATTACHED_PIC | AV_DISPOSITION_TIMED_THUMBNAILS;
            if (st->nb_index_entries) {
                // Retrieve the first frame, if possible
                AVPacket pkt;
                AVIndexEntry *sample = &st->index_entries[0];
                if (avio_seek(sc->pb, sample->pos, SEEK_SET) != sample->pos) {
                    av_log(s, AV_LOG_ERROR, "Failed to retrieve first frame\n");
                    goto finish;
                }

                if (av_get_packet(sc->pb, &pkt, sample->size) < 0)
                    goto finish;

                st->attached_pic              = pkt;
                st->attached_pic.stream_index = st->index;
                st->attached_pic.flags       |= AV_PKT_FLAG_KEY;
            }
        } else {
            st->codecpar->codec_type = AVMEDIA_TYPE_DATA;
            st->codecpar->codec_id = AV_CODEC_ID_BIN_DATA;
            st->discard = AVDISCARD_ALL;
            for (i = 0; i < st->nb_index_entries; i++) {
                AVIndexEntry *sample = &st->index_entries[i];
                int64_t end = i+1 < st->nb_index_entries ? st->index_entries[i+1].timestamp : st->duration;
                uint8_t *title;
                uint16_t ch;
                int len, title_len;

                if (end < sample->timestamp) {
                    av_log(s, AV_LOG_WARNING, "ignoring stream duration which is shorter than chapters\n");
                    end = AV_NOPTS_VALUE;
                }

                if (avio_seek(sc->pb, sample->pos, SEEK_SET) != sample->pos) {
                    av_log(s, AV_LOG_ERROR, "Chapter %d not found in file\n", i);
                    goto finish;
                }

                // the first two bytes are the length of the title
                len = avio_rb16(sc->pb);
                if (len > sample->size-2)
                    continue;
                title_len = 2*len + 1;
                if (!(title = av_mallocz(title_len)))
                    goto finish;

                // The samples could theoretically be in any encoding if there's an encd
                // atom following, but in practice are only utf-8 or utf-16, distinguished
                // instead by the presence of a BOM
                if (!len) {
                    title[0] = 0;
                } else {
                    ch = avio_rb16(sc->pb);
                    if (ch == 0xfeff)
                        avio_get_str16be(sc->pb, len, title, title_len);
                    else if (ch == 0xfffe)
                        avio_get_str16le(sc->pb, len, title, title_len);
                    else {
                        AV_WB16(title, ch);
                        if (len == 1 || len == 2)
                            title[len] = 0;
                        else
                            avio_get_str(sc->pb, INT_MAX, title + 2, len - 1);
                    }
                }

                avpriv_new_chapter(s, i, st->time_base, sample->timestamp, end, title);
                av_freep(&title);
            }
        }
finish:
        avio_seek(sc->pb, cur_pos, SEEK_SET);
    }
}

static int parse_timecode_in_framenum_format(AVFormatContext *s, AVStream *st,
                                             uint32_t value, int flags)
{
    AVTimecode tc;
    char buf[AV_TIMECODE_STR_SIZE];
    AVRational rate = st->avg_frame_rate;
    int ret = av_timecode_init(&tc, rate, flags, 0, s);
    if (ret < 0)
        return ret;
    av_dict_set(&st->metadata, "timecode",
                av_timecode_make_string(&tc, buf, value), 0);
    return 0;
}

static int mov_read_rtmd_track(AVFormatContext *s, AVStream *st)
{
    MOVStreamContext *sc = st->priv_data;
    char buf[AV_TIMECODE_STR_SIZE];
    int64_t cur_pos = avio_tell(sc->pb);
    int hh, mm, ss, ff, drop;

    if (!st->nb_index_entries)
        return -1;

    avio_seek(sc->pb, st->index_entries->pos, SEEK_SET);
    avio_skip(s->pb, 13);
    hh = avio_r8(s->pb);
    mm = avio_r8(s->pb);
    ss = avio_r8(s->pb);
    drop = avio_r8(s->pb);
    ff = avio_r8(s->pb);
    snprintf(buf, AV_TIMECODE_STR_SIZE, "%02d:%02d:%02d%c%02d",
             hh, mm, ss, drop ? ';' : ':', ff);
    av_dict_set(&st->metadata, "timecode", buf, 0);

    avio_seek(sc->pb, cur_pos, SEEK_SET);
    return 0;
}

static int mov_read_timecode_track(AVFormatContext *s, AVStream *st)
{
    MOVStreamContext *sc = st->priv_data;
    int flags = 0;
    int64_t cur_pos = avio_tell(sc->pb);
    uint32_t value;

    if (!st->nb_index_entries)
        return -1;

    avio_seek(sc->pb, st->index_entries->pos, SEEK_SET);
    value = avio_rb32(s->pb);

    if (sc->tmcd_flags & 0x0001) flags |= AV_TIMECODE_FLAG_DROPFRAME;
    if (sc->tmcd_flags & 0x0002) flags |= AV_TIMECODE_FLAG_24HOURSMAX;
    if (sc->tmcd_flags & 0x0004) flags |= AV_TIMECODE_FLAG_ALLOWNEGATIVE;

    /* Assume Counter flag is set to 1 in tmcd track (even though it is likely
     * not the case) and thus assume "frame number format" instead of QT one.
     * No sample with tmcd track can be found with a QT timecode at the moment,
     * despite what the tmcd track "suggests" (Counter flag set to 0 means QT
     * format). */
    parse_timecode_in_framenum_format(s, st, value, flags);

    avio_seek(sc->pb, cur_pos, SEEK_SET);
    return 0;
}

static int mov_read_close(AVFormatContext *s)
{
    MOVContext *mov = s->priv_data;
    int i, j;

    for (i = 0; i < s->nb_streams; i++) {
        AVStream *st = s->streams[i];
        MOVStreamContext *sc = st->priv_data;

        if (!sc)
            continue;

        av_freep(&sc->ctts_data);
        for (j = 0; j < sc->drefs_count; j++) {
            av_freep(&sc->drefs[j].path);
            av_freep(&sc->drefs[j].dir);
        }
        av_freep(&sc->drefs);

        sc->drefs_count = 0;

        if (!sc->pb_is_copied)
            ff_format_io_close(s, &sc->pb);

        sc->pb = NULL;
        av_freep(&sc->chunk_offsets);
        av_freep(&sc->stsc_data);
        av_freep(&sc->sample_sizes);
        av_freep(&sc->keyframes);
        av_freep(&sc->stts_data);
        av_freep(&sc->stps_data);
        av_freep(&sc->elst_data);
        av_freep(&sc->rap_group);
        av_freep(&sc->display_matrix);
        av_freep(&sc->index_ranges);

        if (sc->extradata)
            for (j = 0; j < sc->stsd_count; j++)
                av_free(sc->extradata[j]);
        av_freep(&sc->extradata);
        av_freep(&sc->extradata_size);

        av_freep(&sc->cenc.auxiliary_info);
        av_freep(&sc->cenc.auxiliary_info_sizes);
        av_aes_ctr_free(sc->cenc.aes_ctr);

        av_freep(&sc->stereo3d);
        av_freep(&sc->spherical);
        av_freep(&sc->mastering);
        av_freep(&sc->coll);
    }

    if (mov->dv_demux) {
        avformat_free_context(mov->dv_fctx);
        mov->dv_fctx = NULL;
    }

    if (mov->meta_keys) {
        for (i = 1; i < mov->meta_keys_count; i++) {
            av_freep(&mov->meta_keys[i]);
        }
        av_freep(&mov->meta_keys);
    }

    av_freep(&mov->trex_data);
    av_freep(&mov->bitrates);

    for (i = 0; i < mov->frag_index.nb_items; i++) {
        av_freep(&mov->frag_index.item[i].stream_info);
    }
    av_freep(&mov->frag_index.item);

    av_freep(&mov->aes_decrypt);
    av_freep(&mov->chapter_tracks);

    return 0;
}

static int tmcd_is_referenced(AVFormatContext *s, int tmcd_id)
{
    int i;

    for (i = 0; i < s->nb_streams; i++) {
        AVStream *st = s->streams[i];
        MOVStreamContext *sc = st->priv_data;

        if (st->codecpar->codec_type == AVMEDIA_TYPE_VIDEO &&
            sc->timecode_track == tmcd_id)
            return 1;
    }
    return 0;
}

/* look for a tmcd track not referenced by any video track, and export it globally */
static void export_orphan_timecode(AVFormatContext *s)
{
    int i;

    for (i = 0; i < s->nb_streams; i++) {
        AVStream *st = s->streams[i];

        if (st->codecpar->codec_tag  == MKTAG('t','m','c','d') &&
            !tmcd_is_referenced(s, i + 1)) {
            AVDictionaryEntry *tcr = av_dict_get(st->metadata, "timecode", NULL, 0);
            if (tcr) {
                av_dict_set(&s->metadata, "timecode", tcr->value, 0);
                break;
            }
        }
    }
}

static int read_tfra(MOVContext *mov, AVIOContext *f)
{
    int version, fieldlength, i, j;
    int64_t pos = avio_tell(f);
    uint32_t size = avio_rb32(f);
    unsigned track_id, item_count;

    if (avio_rb32(f) != MKBETAG('t', 'f', 'r', 'a')) {
        return 1;
    }
    av_log(mov->fc, AV_LOG_VERBOSE, "found tfra\n");

    version = avio_r8(f);
    avio_rb24(f);
    track_id = avio_rb32(f);
    fieldlength = avio_rb32(f);
    item_count = avio_rb32(f);
    for (i = 0; i < item_count; i++) {
        int64_t time, offset;
        int index;
        MOVFragmentStreamInfo * frag_stream_info;

        if (avio_feof(f)) {
            return AVERROR_INVALIDDATA;
        }

        if (version == 1) {
            time   = avio_rb64(f);
            offset = avio_rb64(f);
        } else {
            time   = avio_rb32(f);
            offset = avio_rb32(f);
        }

        // The first sample of each stream in a fragment is always a random
        // access sample.  So it's entry in the tfra can be used as the
        // initial PTS of the fragment.
        index = update_frag_index(mov, offset);
        frag_stream_info = get_frag_stream_info(&mov->frag_index, index, track_id);
        if (frag_stream_info &&
            frag_stream_info->first_tfra_pts == AV_NOPTS_VALUE)
            frag_stream_info->first_tfra_pts = time;

        for (j = 0; j < ((fieldlength >> 4) & 3) + 1; j++)
            avio_r8(f);
        for (j = 0; j < ((fieldlength >> 2) & 3) + 1; j++)
            avio_r8(f);
        for (j = 0; j < ((fieldlength >> 0) & 3) + 1; j++)
            avio_r8(f);
    }

    avio_seek(f, pos + size, SEEK_SET);
    return 0;
}

static int mov_read_mfra(MOVContext *c, AVIOContext *f)
{
    int64_t stream_size = avio_size(f);
    int64_t original_pos = avio_tell(f);
    int64_t seek_ret;
    int32_t mfra_size;
    int ret = -1;
    if ((seek_ret = avio_seek(f, stream_size - 4, SEEK_SET)) < 0) {
        ret = seek_ret;
        goto fail;
    }
    mfra_size = avio_rb32(f);
    if (mfra_size < 0 || mfra_size > stream_size) {
        av_log(c->fc, AV_LOG_DEBUG, "doesn't look like mfra (unreasonable size)\n");
        goto fail;
    }
    if ((seek_ret = avio_seek(f, -mfra_size, SEEK_CUR)) < 0) {
        ret = seek_ret;
        goto fail;
    }
    if (avio_rb32(f) != mfra_size) {
        av_log(c->fc, AV_LOG_DEBUG, "doesn't look like mfra (size mismatch)\n");
        goto fail;
    }
    if (avio_rb32(f) != MKBETAG('m', 'f', 'r', 'a')) {
        av_log(c->fc, AV_LOG_DEBUG, "doesn't look like mfra (tag mismatch)\n");
        goto fail;
    }
    av_log(c->fc, AV_LOG_VERBOSE, "stream has mfra\n");
    do {
        ret = read_tfra(c, f);
        if (ret < 0)
            goto fail;
    } while (!ret);
    ret = 0;
fail:
    seek_ret = avio_seek(f, original_pos, SEEK_SET);
    if (seek_ret < 0) {
        av_log(c->fc, AV_LOG_ERROR,
               "failed to seek back after looking for mfra\n");
        ret = seek_ret;
    }
    return ret;
}

static int mov_read_header(AVFormatContext *s)
{
    MOVContext *mov = s->priv_data;
    AVIOContext *pb = s->pb;
    int j, err;
    MOVAtom atom = { AV_RL32("root") };
    int i;

    if (mov->decryption_key_len != 0 && mov->decryption_key_len != AES_CTR_KEY_SIZE) {
        av_log(s, AV_LOG_ERROR, "Invalid decryption key len %d expected %d\n",
            mov->decryption_key_len, AES_CTR_KEY_SIZE);
        return AVERROR(EINVAL);
    }

    mov->fc = s;
    mov->trak_index = -1;
    /* .mov and .mp4 aren't streamable anyway (only progressive download if moov is before mdat) */
    if (pb->seekable & AVIO_SEEKABLE_NORMAL)
        atom.size = avio_size(pb);
    else
        atom.size = INT64_MAX;

    /* check MOV header */
    do {
        if (mov->moov_retry)
            avio_seek(pb, 0, SEEK_SET);
        if ((err = mov_read_default(mov, pb, atom)) < 0) {
            av_log(s, AV_LOG_ERROR, "error reading header\n");
            mov_read_close(s);
            return err;
        }
    } while ((pb->seekable & AVIO_SEEKABLE_NORMAL) && !mov->found_moov && !mov->moov_retry++);
    if (!mov->found_moov) {
        av_log(s, AV_LOG_ERROR, "moov atom not found\n");
        mov_read_close(s);
        return AVERROR_INVALIDDATA;
    }
    av_log(mov->fc, AV_LOG_TRACE, "on_parse_exit_offset=%"PRId64"\n", avio_tell(pb));

    if (pb->seekable & AVIO_SEEKABLE_NORMAL) {
        if (mov->nb_chapter_tracks > 0 && !mov->ignore_chapters)
            mov_read_chapters(s);
        for (i = 0; i < s->nb_streams; i++)
            if (s->streams[i]->codecpar->codec_tag == AV_RL32("tmcd")) {
                mov_read_timecode_track(s, s->streams[i]);
            } else if (s->streams[i]->codecpar->codec_tag == AV_RL32("rtmd")) {
                mov_read_rtmd_track(s, s->streams[i]);
            }
    }

    /* copy timecode metadata from tmcd tracks to the related video streams */
    for (i = 0; i < s->nb_streams; i++) {
        AVStream *st = s->streams[i];
        MOVStreamContext *sc = st->priv_data;
        if (sc->timecode_track > 0) {
            AVDictionaryEntry *tcr;
            int tmcd_st_id = -1;

            for (j = 0; j < s->nb_streams; j++)
                if (s->streams[j]->id == sc->timecode_track)
                    tmcd_st_id = j;

            if (tmcd_st_id < 0 || tmcd_st_id == i)
                continue;
            tcr = av_dict_get(s->streams[tmcd_st_id]->metadata, "timecode", NULL, 0);
            if (tcr)
                av_dict_set(&st->metadata, "timecode", tcr->value, 0);
        }
    }
    export_orphan_timecode(s);

    for (i = 0; i < s->nb_streams; i++) {
        AVStream *st = s->streams[i];
        MOVStreamContext *sc = st->priv_data;
        fix_timescale(mov, sc);
        if(st->codecpar->codec_type == AVMEDIA_TYPE_AUDIO && st->codecpar->codec_id == AV_CODEC_ID_AAC) {
            st->skip_samples = sc->start_pad;
        }
        if (st->codecpar->codec_type == AVMEDIA_TYPE_VIDEO && sc->nb_frames_for_fps > 0 && sc->duration_for_fps > 0)
            av_reduce(&st->avg_frame_rate.num, &st->avg_frame_rate.den,
                      sc->time_scale*(int64_t)sc->nb_frames_for_fps, sc->duration_for_fps, INT_MAX);
        if (st->codecpar->codec_type == AVMEDIA_TYPE_SUBTITLE) {
            if (st->codecpar->width <= 0 || st->codecpar->height <= 0) {
                st->codecpar->width  = sc->width;
                st->codecpar->height = sc->height;
            }
            if (st->codecpar->codec_id == AV_CODEC_ID_DVD_SUBTITLE) {
                if ((err = mov_rewrite_dvd_sub_extradata(st)) < 0)
                    return err;
            }
        }
        if (mov->handbrake_version &&
            mov->handbrake_version <= 1000000*0 + 1000*10 + 2 &&  // 0.10.2
            st->codecpar->codec_id == AV_CODEC_ID_MP3
        ) {
            av_log(s, AV_LOG_VERBOSE, "Forcing full parsing for mp3 stream\n");
            st->need_parsing = AVSTREAM_PARSE_FULL;
        }
    }

    if (mov->trex_data) {
        for (i = 0; i < s->nb_streams; i++) {
            AVStream *st = s->streams[i];
            MOVStreamContext *sc = st->priv_data;
            if (st->duration > 0) {
                if (sc->data_size > INT64_MAX / sc->time_scale / 8) {
                    av_log(s, AV_LOG_ERROR, "Overflow during bit rate calculation %"PRId64" * 8 * %d\n",
                           sc->data_size, sc->time_scale);
                    mov_read_close(s);
                    return AVERROR_INVALIDDATA;
                }
                st->codecpar->bit_rate = sc->data_size * 8 * sc->time_scale / st->duration;
            }
        }
    }

    if (mov->use_mfra_for > 0) {
        for (i = 0; i < s->nb_streams; i++) {
            AVStream *st = s->streams[i];
            MOVStreamContext *sc = st->priv_data;
            if (sc->duration_for_fps > 0) {
                if (sc->data_size > INT64_MAX / sc->time_scale / 8) {
                    av_log(s, AV_LOG_ERROR, "Overflow during bit rate calculation %"PRId64" * 8 * %d\n",
                           sc->data_size, sc->time_scale);
                    mov_read_close(s);
                    return AVERROR_INVALIDDATA;
                }
                st->codecpar->bit_rate = sc->data_size * 8 * sc->time_scale /
                    sc->duration_for_fps;
            }
        }
    }

    for (i = 0; i < mov->bitrates_count && i < s->nb_streams; i++) {
        if (mov->bitrates[i]) {
            s->streams[i]->codecpar->bit_rate = mov->bitrates[i];
        }
    }

    ff_rfps_calculate(s);

    for (i = 0; i < s->nb_streams; i++) {
        AVStream *st = s->streams[i];
        MOVStreamContext *sc = st->priv_data;

        switch (st->codecpar->codec_type) {
        case AVMEDIA_TYPE_AUDIO:
            err = ff_replaygain_export(st, s->metadata);
            if (err < 0) {
                mov_read_close(s);
                return err;
            }
            break;
        case AVMEDIA_TYPE_VIDEO:
            if (sc->display_matrix) {
                err = av_stream_add_side_data(st, AV_PKT_DATA_DISPLAYMATRIX, (uint8_t*)sc->display_matrix,
                                              sizeof(int32_t) * 9);
                if (err < 0)
                    return err;

                sc->display_matrix = NULL;
            }
            if (sc->stereo3d) {
                err = av_stream_add_side_data(st, AV_PKT_DATA_STEREO3D,
                                              (uint8_t *)sc->stereo3d,
                                              sizeof(*sc->stereo3d));
                if (err < 0)
                    return err;

                sc->stereo3d = NULL;
            }
            if (sc->spherical) {
                err = av_stream_add_side_data(st, AV_PKT_DATA_SPHERICAL,
                                              (uint8_t *)sc->spherical,
                                              sc->spherical_size);
                if (err < 0)
                    return err;

                sc->spherical = NULL;
            }
            if (sc->mastering) {
                err = av_stream_add_side_data(st, AV_PKT_DATA_MASTERING_DISPLAY_METADATA,
                                              (uint8_t *)sc->mastering,
                                              sizeof(*sc->mastering));
                if (err < 0)
                    return err;

                sc->mastering = NULL;
            }
            if (sc->coll) {
                err = av_stream_add_side_data(st, AV_PKT_DATA_CONTENT_LIGHT_LEVEL,
                                              (uint8_t *)sc->coll,
                                              sc->coll_size);
                if (err < 0)
                    return err;

                sc->coll = NULL;
            }
            break;
        }
    }
    ff_configure_buffers_for_index(s, AV_TIME_BASE);

    for (i = 0; i < mov->frag_index.nb_items; i++)
        if (mov->frag_index.item[i].moof_offset <= mov->fragment.moof_offset)
            mov->frag_index.item[i].headers_read = 1;

    return 0;
}

static AVIndexEntry *mov_find_next_sample(AVFormatContext *s, AVStream **st)
{
    AVIndexEntry *sample = NULL;
    int64_t best_dts = INT64_MAX;
    int i;
    for (i = 0; i < s->nb_streams; i++) {
        AVStream *avst = s->streams[i];
        MOVStreamContext *msc = avst->priv_data;
        if (msc->pb && msc->current_sample < avst->nb_index_entries) {
            AVIndexEntry *current_sample = &avst->index_entries[msc->current_sample];
            int64_t dts = av_rescale(current_sample->timestamp, AV_TIME_BASE, msc->time_scale);
            av_log(s, AV_LOG_TRACE, "stream %d, sample %d, dts %"PRId64"\n", i, msc->current_sample, dts);
            if (!sample || (!(s->pb->seekable & AVIO_SEEKABLE_NORMAL) && current_sample->pos < sample->pos) ||
                ((s->pb->seekable & AVIO_SEEKABLE_NORMAL) &&
                 ((msc->pb != s->pb && dts < best_dts) || (msc->pb == s->pb &&
                 ((FFABS(best_dts - dts) <= AV_TIME_BASE && current_sample->pos < sample->pos) ||
                  (FFABS(best_dts - dts) > AV_TIME_BASE && dts < best_dts)))))) {
                sample = current_sample;
                best_dts = dts;
                *st = avst;
            }
        }
    }
    return sample;
}

static int should_retry(AVIOContext *pb, int error_code) {
    if (error_code == AVERROR_EOF || avio_feof(pb))
        return 0;

    return 1;
}

static int mov_switch_root(AVFormatContext *s, int64_t target, int index)
{
    int ret;
    MOVContext *mov = s->priv_data;

    if (index >= 0 && index < mov->frag_index.nb_items)
        target = mov->frag_index.item[index].moof_offset;
    if (avio_seek(s->pb, target, SEEK_SET) != target) {
        av_log(mov->fc, AV_LOG_ERROR, "root atom offset 0x%"PRIx64": partial file\n", target);
        return AVERROR_INVALIDDATA;
    }

    mov->next_root_atom = 0;
    if (index < 0 || index >= mov->frag_index.nb_items)
        index = search_frag_moof_offset(&mov->frag_index, target);
    if (index < mov->frag_index.nb_items) {
        if (index + 1 < mov->frag_index.nb_items)
            mov->next_root_atom = mov->frag_index.item[index + 1].moof_offset;
        if (mov->frag_index.item[index].headers_read)
            return 0;
        mov->frag_index.item[index].headers_read = 1;
    }

    mov->found_mdat = 0;

    ret = mov_read_default(mov, s->pb, (MOVAtom){ AV_RL32("root"), INT64_MAX });
    if (ret < 0)
        return ret;
    if (avio_feof(s->pb))
        return AVERROR_EOF;
    av_log(s, AV_LOG_TRACE, "read fragments, offset 0x%"PRIx64"\n", avio_tell(s->pb));

    return 1;
}

static int mov_change_extradata(MOVStreamContext *sc, AVPacket *pkt)
{
    uint8_t *side, *extradata;
    int extradata_size;

    /* Save the current index. */
    sc->last_stsd_index = sc->stsc_data[sc->stsc_index].id - 1;

    /* Notify the decoder that extradata changed. */
    extradata_size = sc->extradata_size[sc->last_stsd_index];
    extradata = sc->extradata[sc->last_stsd_index];
    if (extradata_size > 0 && extradata) {
        side = av_packet_new_side_data(pkt,
                                       AV_PKT_DATA_NEW_EXTRADATA,
                                       extradata_size);
        if (!side)
            return AVERROR(ENOMEM);
        memcpy(side, extradata, extradata_size);
    }

    return 0;
}

static int mov_read_packet(AVFormatContext *s, AVPacket *pkt)
{
    MOVContext *mov = s->priv_data;
    MOVStreamContext *sc;
    AVIndexEntry *sample;
    AVStream *st = NULL;
    int64_t current_index;
    int ret;
    mov->fc = s;
 retry:
    sample = mov_find_next_sample(s, &st);
    if (!sample || (mov->next_root_atom && sample->pos > mov->next_root_atom)) {
        if (!mov->next_root_atom)
            return AVERROR_EOF;
        if ((ret = mov_switch_root(s, mov->next_root_atom, -1)) < 0)
            return ret;
        goto retry;
    }
    sc = st->priv_data;
    /* must be done just before reading, to avoid infinite loop on sample */
    current_index = sc->current_index;
    mov_current_sample_inc(sc);

    if (mov->next_root_atom) {
        sample->pos = FFMIN(sample->pos, mov->next_root_atom);
        sample->size = FFMIN(sample->size, (mov->next_root_atom - sample->pos));
    }

    if (st->discard != AVDISCARD_ALL) {
        int64_t ret64 = avio_seek(sc->pb, sample->pos, SEEK_SET);
        if (ret64 != sample->pos) {
            av_log(mov->fc, AV_LOG_ERROR, "stream %d, offset 0x%"PRIx64": partial file\n",
                   sc->ffindex, sample->pos);
            if (should_retry(sc->pb, ret64)) {
                mov_current_sample_dec(sc);
            }
            return AVERROR_INVALIDDATA;
        }

        if( st->discard == AVDISCARD_NONKEY && 0==(sample->flags & AVINDEX_KEYFRAME) ) {
            av_log(mov->fc, AV_LOG_DEBUG, "Nonkey frame from stream %d discarded due to AVDISCARD_NONKEY\n", sc->ffindex);
            goto retry;
        }

        ret = av_get_packet(sc->pb, pkt, sample->size);
        if (ret < 0) {
            if (should_retry(sc->pb, ret)) {
                mov_current_sample_dec(sc);
            }
            return ret;
        }
        if (sc->has_palette) {
            uint8_t *pal;

            pal = av_packet_new_side_data(pkt, AV_PKT_DATA_PALETTE, AVPALETTE_SIZE);
            if (!pal) {
                av_log(mov->fc, AV_LOG_ERROR, "Cannot append palette to packet\n");
            } else {
                memcpy(pal, sc->palette, AVPALETTE_SIZE);
                sc->has_palette = 0;
            }
        }
#if CONFIG_DV_DEMUXER
        if (mov->dv_demux && sc->dv_audio_container) {
            avpriv_dv_produce_packet(mov->dv_demux, pkt, pkt->data, pkt->size, pkt->pos);
            av_freep(&pkt->data);
            pkt->size = 0;
            ret = avpriv_dv_get_packet(mov->dv_demux, pkt);
            if (ret < 0)
                return ret;
        }
#endif
        if (st->codecpar->codec_id == AV_CODEC_ID_MP3 && !st->need_parsing && pkt->size > 4) {
            if (ff_mpa_check_header(AV_RB32(pkt->data)) < 0)
                st->need_parsing = AVSTREAM_PARSE_FULL;
        }
    }

    pkt->stream_index = sc->ffindex;
    pkt->dts = sample->timestamp;
    if (sample->flags & AVINDEX_DISCARD_FRAME) {
        pkt->flags |= AV_PKT_FLAG_DISCARD;
    }
    if (sc->ctts_data && sc->ctts_index < sc->ctts_count) {
        pkt->pts = pkt->dts + sc->dts_shift + sc->ctts_data[sc->ctts_index].duration;
        /* update ctts context */
        sc->ctts_sample++;
        if (sc->ctts_index < sc->ctts_count &&
            sc->ctts_data[sc->ctts_index].count == sc->ctts_sample) {
            sc->ctts_index++;
            sc->ctts_sample = 0;
        }
    } else {
        int64_t next_dts = (sc->current_sample < st->nb_index_entries) ?
            st->index_entries[sc->current_sample].timestamp : st->duration;

        if (next_dts >= pkt->dts)
            pkt->duration = next_dts - pkt->dts;
        pkt->pts = pkt->dts;
    }
    if (st->discard == AVDISCARD_ALL)
        goto retry;
    pkt->flags |= sample->flags & AVINDEX_KEYFRAME ? AV_PKT_FLAG_KEY : 0;
    pkt->pos = sample->pos;

    /* Multiple stsd handling. */
    if (sc->stsc_data) {
        /* Keep track of the stsc index for the given sample, then check
        * if the stsd index is different from the last used one. */
        sc->stsc_sample++;
        if (mov_stsc_index_valid(sc->stsc_index, sc->stsc_count) &&
            mov_get_stsc_samples(sc, sc->stsc_index) == sc->stsc_sample) {
            sc->stsc_index++;
            sc->stsc_sample = 0;
        /* Do not check indexes after a switch. */
        } else if (sc->stsc_data[sc->stsc_index].id > 0 &&
                   sc->stsc_data[sc->stsc_index].id - 1 < sc->stsd_count &&
                   sc->stsc_data[sc->stsc_index].id - 1 != sc->last_stsd_index) {
            ret = mov_change_extradata(sc, pkt);
            if (ret < 0)
                return ret;
        }
    }

    if (mov->aax_mode)
        aax_filter(pkt->data, pkt->size, mov);

    if (sc->cenc.aes_ctr) {
        ret = cenc_filter(mov, sc, current_index, pkt->data, pkt->size);
        if (ret) {
            return ret;
        }
    }

    return 0;
}

static int mov_seek_fragment(AVFormatContext *s, AVStream *st, int64_t timestamp)
{
    MOVContext *mov = s->priv_data;
    int index;

    if (!mov->frag_index.complete)
        return 0;

    index = search_frag_timestamp(&mov->frag_index, st, timestamp);
    if (index < 0)
        index = 0;
    if (!mov->frag_index.item[index].headers_read)
        return mov_switch_root(s, -1, index);
    if (index + 1 < mov->frag_index.nb_items)
        mov->next_root_atom = mov->frag_index.item[index + 1].moof_offset;

    return 0;
}

static int mov_seek_stream(AVFormatContext *s, AVStream *st, int64_t timestamp, int flags)
{
    MOVStreamContext *sc = st->priv_data;
    int sample, time_sample, ret;
    unsigned int i;

    // Here we consider timestamp to be PTS, hence try to offset it so that we
    // can search over the DTS timeline.
    timestamp -= (sc->min_corrected_pts + sc->dts_shift);

    ret = mov_seek_fragment(s, st, timestamp);
    if (ret < 0)
        return ret;

    sample = av_index_search_timestamp(st, timestamp, flags);
    av_log(s, AV_LOG_TRACE, "stream %d, timestamp %"PRId64", sample %d\n", st->index, timestamp, sample);
    if (sample < 0 && st->nb_index_entries && timestamp < st->index_entries[0].timestamp)
        sample = 0;
    if (sample < 0) /* not sure what to do */
        return AVERROR_INVALIDDATA;
    mov_current_sample_set(sc, sample);
    av_log(s, AV_LOG_TRACE, "stream %d, found sample %d\n", st->index, sc->current_sample);
    /* adjust ctts index */
    if (sc->ctts_data) {
        time_sample = 0;
        for (i = 0; i < sc->ctts_count; i++) {
            int next = time_sample + sc->ctts_data[i].count;
            if (next > sc->current_sample) {
                sc->ctts_index = i;
                sc->ctts_sample = sc->current_sample - time_sample;
                break;
            }
            time_sample = next;
        }
    }

    /* adjust stsd index */
    time_sample = 0;
    for (i = 0; i < sc->stsc_count; i++) {
        int64_t next = time_sample + mov_get_stsc_samples(sc, i);
        if (next > sc->current_sample) {
            sc->stsc_index = i;
            sc->stsc_sample = sc->current_sample - time_sample;
            break;
        }
        av_assert0(next == (int)next);
        time_sample = next;
    }

    return sample;
}

static int mov_read_seek(AVFormatContext *s, int stream_index, int64_t sample_time, int flags)
{
    MOVContext *mc = s->priv_data;
    AVStream *st;
    int sample;
    int i;

    if (stream_index >= s->nb_streams)
        return AVERROR_INVALIDDATA;

    st = s->streams[stream_index];
    sample = mov_seek_stream(s, st, sample_time, flags);
    if (sample < 0)
        return sample;

    if (mc->seek_individually) {
        /* adjust seek timestamp to found sample timestamp */
        int64_t seek_timestamp = st->index_entries[sample].timestamp;

        for (i = 0; i < s->nb_streams; i++) {
            int64_t timestamp;
            MOVStreamContext *sc = s->streams[i]->priv_data;
            st = s->streams[i];
            st->skip_samples = (sample_time <= 0) ? sc->start_pad : 0;

            if (stream_index == i)
                continue;

            timestamp = av_rescale_q(seek_timestamp, s->streams[stream_index]->time_base, st->time_base);
            mov_seek_stream(s, st, timestamp, flags);
        }
    } else {
        for (i = 0; i < s->nb_streams; i++) {
            MOVStreamContext *sc;
            st = s->streams[i];
            sc = st->priv_data;
            mov_current_sample_set(sc, 0);
        }
        while (1) {
            MOVStreamContext *sc;
            AVIndexEntry *entry = mov_find_next_sample(s, &st);
            if (!entry)
                return AVERROR_INVALIDDATA;
            sc = st->priv_data;
            if (sc->ffindex == stream_index && sc->current_sample == sample)
                break;
            mov_current_sample_inc(sc);
        }
    }
    return 0;
}

#define OFFSET(x) offsetof(MOVContext, x)
#define FLAGS AV_OPT_FLAG_VIDEO_PARAM | AV_OPT_FLAG_DECODING_PARAM
static const AVOption mov_options[] = {
    {"use_absolute_path",
        "allow using absolute path when opening alias, this is a possible security issue",
        OFFSET(use_absolute_path), AV_OPT_TYPE_BOOL, {.i64 = 0},
        0, 1, FLAGS},
    {"seek_streams_individually",
        "Seek each stream individually to the to the closest point",
        OFFSET(seek_individually), AV_OPT_TYPE_BOOL, { .i64 = 1 },
        0, 1, FLAGS},
    {"ignore_editlist", "Ignore the edit list atom.", OFFSET(ignore_editlist), AV_OPT_TYPE_BOOL, {.i64 = 0},
        0, 1, FLAGS},
    {"advanced_editlist",
        "Modify the AVIndex according to the editlists. Use this option to decode in the order specified by the edits.",
        OFFSET(advanced_editlist), AV_OPT_TYPE_BOOL, {.i64 = 1},
        0, 1, FLAGS},
    {"ignore_chapters", "", OFFSET(ignore_chapters), AV_OPT_TYPE_BOOL, {.i64 = 0},
        0, 1, FLAGS},
    {"use_mfra_for",
        "use mfra for fragment timestamps",
        OFFSET(use_mfra_for), AV_OPT_TYPE_INT, {.i64 = FF_MOV_FLAG_MFRA_AUTO},
        -1, FF_MOV_FLAG_MFRA_PTS, FLAGS,
        "use_mfra_for"},
    {"auto", "auto", 0, AV_OPT_TYPE_CONST, {.i64 = FF_MOV_FLAG_MFRA_AUTO}, 0, 0,
        FLAGS, "use_mfra_for" },
    {"dts", "dts", 0, AV_OPT_TYPE_CONST, {.i64 = FF_MOV_FLAG_MFRA_DTS}, 0, 0,
        FLAGS, "use_mfra_for" },
    {"pts", "pts", 0, AV_OPT_TYPE_CONST, {.i64 = FF_MOV_FLAG_MFRA_PTS}, 0, 0,
        FLAGS, "use_mfra_for" },
    { "export_all", "Export unrecognized metadata entries", OFFSET(export_all),
        AV_OPT_TYPE_BOOL, { .i64 = 0 }, 0, 1, .flags = FLAGS },
    { "export_xmp", "Export full XMP metadata", OFFSET(export_xmp),
        AV_OPT_TYPE_BOOL, { .i64 = 0 }, 0, 1, .flags = FLAGS },
    { "activation_bytes", "Secret bytes for Audible AAX files", OFFSET(activation_bytes),
        AV_OPT_TYPE_BINARY, .flags = AV_OPT_FLAG_DECODING_PARAM },
    { "audible_fixed_key", // extracted from libAAX_SDK.so and AAXSDKWin.dll files!
        "Fixed key used for handling Audible AAX files", OFFSET(audible_fixed_key),
        AV_OPT_TYPE_BINARY, {.str="77214d4b196a87cd520045fd20a51d67"},
        .flags = AV_OPT_FLAG_DECODING_PARAM },
    { "decryption_key", "The media decryption key (hex)", OFFSET(decryption_key), AV_OPT_TYPE_BINARY, .flags = AV_OPT_FLAG_DECODING_PARAM },
    { "enable_drefs", "Enable external track support.", OFFSET(enable_drefs), AV_OPT_TYPE_BOOL,
        {.i64 = 0}, 0, 1, FLAGS },

    { NULL },
};

static const AVClass mov_class = {
    .class_name = "mov,mp4,m4a,3gp,3g2,mj2",
    .item_name  = av_default_item_name,
    .option     = mov_options,
    .version    = LIBAVUTIL_VERSION_INT,
};

AVInputFormat ff_mov_demuxer = {
    .name           = "mov,mp4,m4a,3gp,3g2,mj2",
    .long_name      = NULL_IF_CONFIG_SMALL("QuickTime / MOV"),
    .priv_class     = &mov_class,
    .priv_data_size = sizeof(MOVContext),
    .extensions     = "mov,mp4,m4a,3gp,3g2,mj2",
    .read_probe     = mov_probe,
    .read_header    = mov_read_header,
    .read_packet    = mov_read_packet,
    .read_close     = mov_read_close,
    .read_seek      = mov_read_seek,
    .flags          = AVFMT_NO_BYTE_SEEK,
};