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FFmpeg/libavformat/flvdec.c

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  1. /*

  2.  * FLV demuxer

  3.  * Copyright (c) 2003 The FFmpeg Project

  4.  *

  5.  * This demuxer will generate a 1 byte extradata for VP6F content.

  6.  * It is composed of:

  7.  *  - upper 4 bits: difference between encoded width and visible width

  8.  *  - lower 4 bits: difference between encoded height and visible height

  9.  *

  10.  * This file is part of FFmpeg.

  11.  *

  12.  * FFmpeg is free software; you can redistribute it and/or

  13.  * modify it under the terms of the GNU Lesser General Public

  14.  * License as published by the Free Software Foundation; either

  15.  * version 2.1 of the License, or (at your option) any later version.

  16.  *

  17.  * FFmpeg is distributed in the hope that it will be useful,

  18.  * but WITHOUT ANY WARRANTY; without even the implied warranty of

  19.  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU

  20.  * Lesser General Public License for more details.

  21.  *

  22.  * You should have received a copy of the GNU Lesser General Public

  23.  * License along with FFmpeg; if not, write to the Free Software

  24.  * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA

  25.  */

  26. 

  27. #include "libavutil/avstring.h"

  28. #include "libavutil/channel_layout.h"

  29. #include "libavutil/dict.h"

  30. #include "libavutil/opt.h"

  31. #include "libavutil/intfloat.h"

  32. #include "libavutil/mathematics.h"

  33. #include "libavcodec/bytestream.h"

  34. #include "libavcodec/mpeg4audio.h"

  35. #include "avformat.h"

  36. #include "internal.h"

  37. #include "avio_internal.h"

  38. #include "flv.h"

  39. 

  40. #define VALIDATE_INDEX_TS_THRESH 2500

  41. 

  42. #define RESYNC_BUFFER_SIZE (1<<20)

  43. 

  44. typedef struct FLVContext {

  45.     const AVClass *class; ///< Class for private options.

  46.     int trust_metadata;   ///< configure streams according onMetaData

  47.     int wrong_dts;        ///< wrong dts due to negative cts

  48.     uint8_t *new_extradata[FLV_STREAM_TYPE_NB];

  49.     int new_extradata_size[FLV_STREAM_TYPE_NB];

  50.     int last_sample_rate;

  51.     int last_channels;

  52.     struct {

  53.         int64_t dts;

  54.         int64_t pos;

  55.     } validate_index[2];

  56.     int validate_next;

  57.     int validate_count;

  58.     int searched_for_end;

  59. 

  60.     uint8_t resync_buffer[2*RESYNC_BUFFER_SIZE];

  61. 

  62.     int broken_sizes;

  63.     int sum_flv_tag_size;

  64. 

  65.     int last_keyframe_stream_index;

  66.     int keyframe_count;

  67.     int64_t video_bit_rate;

  68.     int64_t audio_bit_rate;

  69.     int64_t *keyframe_times;

  70.     int64_t *keyframe_filepositions;

  71.     int missing_streams;

  72.     AVRational framerate;

  73. } FLVContext;

  74. 

  75. static int probe(AVProbeData *p, int live)

  76. {

  77.     const uint8_t *d = p->buf;

  78.     unsigned offset = AV_RB32(d + 5);

  79. 

  80.     if (d[0] == 'F' &&

  81.         d[1] == 'L' &&

  82.         d[2] == 'V' &&

  83.         d[3] < 5 && d[5] == 0 &&

  84.         offset + 100 < p->buf_size &&

  85.         offset > 8) {

  86.         int is_live = !memcmp(d + offset + 40, "NGINX RTMP", 10);

  87. 

  88.         if (live == is_live)

  89.             return AVPROBE_SCORE_MAX;

  90.     }

  91.     return 0;

  92. }

  93. 

  94. static int flv_probe(AVProbeData *p)

  95. {

  96.     return probe(p, 0);

  97. }

  98. 

  99. static int live_flv_probe(AVProbeData *p)

  100. {

  101.     return probe(p, 1);

  102. }

  103. 

  104. static void add_keyframes_index(AVFormatContext *s)

  105. {

  106.     FLVContext *flv   = s->priv_data;

  107.     AVStream *stream  = NULL;

  108.     unsigned int i    = 0;

  109. 

  110.     if (flv->last_keyframe_stream_index < 0) {

  111.         av_log(s, AV_LOG_DEBUG, "keyframe stream hasn't been created\n");

  112.         return;

  113.     }

  114. 

  115.     av_assert0(flv->last_keyframe_stream_index <= s->nb_streams);

  116.     stream = s->streams[flv->last_keyframe_stream_index];

  117. 

  118.     if (stream->nb_index_entries == 0) {

  119.         for (i = 0; i < flv->keyframe_count; i++) {

  120.             av_log(s, AV_LOG_TRACE, "keyframe filepositions = %"PRId64" times = %"PRId64"\n",

  121.                    flv->keyframe_filepositions[i], flv->keyframe_times[i] * 1000);

  122.             av_add_index_entry(stream, flv->keyframe_filepositions[i],

  123.                 flv->keyframe_times[i] * 1000, 0, 0, AVINDEX_KEYFRAME);

  124.         }

  125.     } else

  126.         av_log(s, AV_LOG_WARNING, "Skipping duplicate index\n");

  127. 

  128.     if (stream->codecpar->codec_type == AVMEDIA_TYPE_VIDEO) {

  129.         av_freep(&flv->keyframe_times);

  130.         av_freep(&flv->keyframe_filepositions);

  131.         flv->keyframe_count = 0;

  132.     }

  133. }

  134. 

  135. static AVStream *create_stream(AVFormatContext *s, int codec_type)

  136. {

  137.     FLVContext *flv   = s->priv_data;

  138.     AVStream *st = avformat_new_stream(s, NULL);

  139.     if (!st)

  140.         return NULL;

  141.     st->codecpar->codec_type = codec_type;

  142.     if (s->nb_streams>=3 ||(   s->nb_streams==2

  143.                            && s->streams[0]->codecpar->codec_type != AVMEDIA_TYPE_SUBTITLE

  144.                            && s->streams[1]->codecpar->codec_type != AVMEDIA_TYPE_SUBTITLE))

  145.         s->ctx_flags &= ~AVFMTCTX_NOHEADER;

  146.     if (codec_type == AVMEDIA_TYPE_AUDIO) {

  147.         st->codecpar->bit_rate = flv->audio_bit_rate;

  148.         flv->missing_streams &= ~FLV_HEADER_FLAG_HASAUDIO;

  149.     }

  150.     if (codec_type == AVMEDIA_TYPE_VIDEO) {

  151.         st->codecpar->bit_rate = flv->video_bit_rate;

  152.         flv->missing_streams &= ~FLV_HEADER_FLAG_HASVIDEO;

  153.         st->avg_frame_rate = flv->framerate;

  154.     }

  155. 

  156. 

  157.     avpriv_set_pts_info(st, 32, 1, 1000); /* 32 bit pts in ms */

  158.     flv->last_keyframe_stream_index = s->nb_streams - 1;

  159.     add_keyframes_index(s);

  160.     return st;

  161. }

  162. 

  163. static int flv_same_audio_codec(AVCodecParameters *apar, int flags)

  164. {

  165.     int bits_per_coded_sample = (flags & FLV_AUDIO_SAMPLESIZE_MASK) ? 16 : 8;

  166.     int flv_codecid           = flags & FLV_AUDIO_CODECID_MASK;

  167.     int codec_id;

  168. 

  169.     if (!apar->codec_id && !apar->codec_tag)

  170.         return 1;

  171. 

  172.     if (apar->bits_per_coded_sample != bits_per_coded_sample)

  173.         return 0;

  174. 

  175.     switch (flv_codecid) {

  176.     // no distinction between S16 and S8 PCM codec flags

  177.     case FLV_CODECID_PCM:

  178.         codec_id = bits_per_coded_sample == 8

  179.                    ? AV_CODEC_ID_PCM_U8

  180. #if HAVE_BIGENDIAN

  181.                    : AV_CODEC_ID_PCM_S16BE;

  182. #else

  183.                    : AV_CODEC_ID_PCM_S16LE;

  184. #endif

  185.         return codec_id == apar->codec_id;

  186.     case FLV_CODECID_PCM_LE:

  187.         codec_id = bits_per_coded_sample == 8

  188.                    ? AV_CODEC_ID_PCM_U8

  189.                    : AV_CODEC_ID_PCM_S16LE;

  190.         return codec_id == apar->codec_id;

  191.     case FLV_CODECID_AAC:

  192.         return apar->codec_id == AV_CODEC_ID_AAC;

  193.     case FLV_CODECID_ADPCM:

  194.         return apar->codec_id == AV_CODEC_ID_ADPCM_SWF;

  195.     case FLV_CODECID_SPEEX:

  196.         return apar->codec_id == AV_CODEC_ID_SPEEX;

  197.     case FLV_CODECID_MP3:

  198.         return apar->codec_id == AV_CODEC_ID_MP3;

  199.     case FLV_CODECID_NELLYMOSER_8KHZ_MONO:

  200.     case FLV_CODECID_NELLYMOSER_16KHZ_MONO:

  201.     case FLV_CODECID_NELLYMOSER:

  202.         return apar->codec_id == AV_CODEC_ID_NELLYMOSER;

  203.     case FLV_CODECID_PCM_MULAW:

  204.         return apar->sample_rate == 8000 &&

  205.                apar->codec_id    == AV_CODEC_ID_PCM_MULAW;

  206.     case FLV_CODECID_PCM_ALAW:

  207.         return apar->sample_rate == 8000 &&

  208.                apar->codec_id    == AV_CODEC_ID_PCM_ALAW;

  209.     default:

  210.         return apar->codec_tag == (flv_codecid >> FLV_AUDIO_CODECID_OFFSET);

  211.     }

  212. }

  213. 

  214. static void flv_set_audio_codec(AVFormatContext *s, AVStream *astream,

  215.                                 AVCodecParameters *apar, int flv_codecid)

  216. {

  217.     switch (flv_codecid) {

  218.     // no distinction between S16 and S8 PCM codec flags

  219.     case FLV_CODECID_PCM:

  220.         apar->codec_id = apar->bits_per_coded_sample == 8

  221.                            ? AV_CODEC_ID_PCM_U8

  222. #if HAVE_BIGENDIAN

  223.                            : AV_CODEC_ID_PCM_S16BE;

  224. #else

  225.                            : AV_CODEC_ID_PCM_S16LE;

  226. #endif

  227.         break;

  228.     case FLV_CODECID_PCM_LE:

  229.         apar->codec_id = apar->bits_per_coded_sample == 8

  230.                            ? AV_CODEC_ID_PCM_U8

  231.                            : AV_CODEC_ID_PCM_S16LE;

  232.         break;

  233.     case FLV_CODECID_AAC:

  234.         apar->codec_id = AV_CODEC_ID_AAC;

  235.         break;

  236.     case FLV_CODECID_ADPCM:

  237.         apar->codec_id = AV_CODEC_ID_ADPCM_SWF;

  238.         break;

  239.     case FLV_CODECID_SPEEX:

  240.         apar->codec_id    = AV_CODEC_ID_SPEEX;

  241.         apar->sample_rate = 16000;

  242.         break;

  243.     case FLV_CODECID_MP3:

  244.         apar->codec_id      = AV_CODEC_ID_MP3;

  245.         astream->need_parsing = AVSTREAM_PARSE_FULL;

  246.         break;

  247.     case FLV_CODECID_NELLYMOSER_8KHZ_MONO:

  248.         // in case metadata does not otherwise declare samplerate

  249.         apar->sample_rate = 8000;

  250.         apar->codec_id    = AV_CODEC_ID_NELLYMOSER;

  251.         break;

  252.     case FLV_CODECID_NELLYMOSER_16KHZ_MONO:

  253.         apar->sample_rate = 16000;

  254.         apar->codec_id    = AV_CODEC_ID_NELLYMOSER;

  255.         break;

  256.     case FLV_CODECID_NELLYMOSER:

  257.         apar->codec_id = AV_CODEC_ID_NELLYMOSER;

  258.         break;

  259.     case FLV_CODECID_PCM_MULAW:

  260.         apar->sample_rate = 8000;

  261.         apar->codec_id    = AV_CODEC_ID_PCM_MULAW;

  262.         break;

  263.     case FLV_CODECID_PCM_ALAW:

  264.         apar->sample_rate = 8000;

  265.         apar->codec_id    = AV_CODEC_ID_PCM_ALAW;

  266.         break;

  267.     default:

  268.         avpriv_request_sample(s, "Audio codec (%x)",

  269.                flv_codecid >> FLV_AUDIO_CODECID_OFFSET);

  270.         apar->codec_tag = flv_codecid >> FLV_AUDIO_CODECID_OFFSET;

  271.     }

  272. }

  273. 

  274. static int flv_same_video_codec(AVCodecParameters *vpar, int flags)

  275. {

  276.     int flv_codecid = flags & FLV_VIDEO_CODECID_MASK;

  277. 

  278.     if (!vpar->codec_id && !vpar->codec_tag)

  279.         return 1;

  280. 

  281.     switch (flv_codecid) {

  282.     case FLV_CODECID_H263:

  283.         return vpar->codec_id == AV_CODEC_ID_FLV1;

  284.     case FLV_CODECID_SCREEN:

  285.         return vpar->codec_id == AV_CODEC_ID_FLASHSV;

  286.     case FLV_CODECID_SCREEN2:

  287.         return vpar->codec_id == AV_CODEC_ID_FLASHSV2;

  288.     case FLV_CODECID_VP6:

  289.         return vpar->codec_id == AV_CODEC_ID_VP6F;

  290.     case FLV_CODECID_VP6A:

  291.         return vpar->codec_id == AV_CODEC_ID_VP6A;

  292.     case FLV_CODECID_H264:

  293.         return vpar->codec_id == AV_CODEC_ID_H264;

  294.     default:

  295.         return vpar->codec_tag == flv_codecid;

  296.     }

  297. }

  298. 

  299. static int flv_set_video_codec(AVFormatContext *s, AVStream *vstream,

  300.                                int flv_codecid, int read)

  301. {

  302.     int ret = 0;

  303.     AVCodecParameters *par = vstream->codecpar;

  304.     enum AVCodecID old_codec_id = vstream->codecpar->codec_id;

  305.     switch (flv_codecid) {

  306.     case FLV_CODECID_H263:

  307.         par->codec_id = AV_CODEC_ID_FLV1;

  308.         break;

  309.     case FLV_CODECID_REALH263:

  310.         par->codec_id = AV_CODEC_ID_H263;

  311.         break; // Really mean it this time

  312.     case FLV_CODECID_SCREEN:

  313.         par->codec_id = AV_CODEC_ID_FLASHSV;

  314.         break;

  315.     case FLV_CODECID_SCREEN2:

  316.         par->codec_id = AV_CODEC_ID_FLASHSV2;

  317.         break;

  318.     case FLV_CODECID_VP6:

  319.         par->codec_id = AV_CODEC_ID_VP6F;

  320.     case FLV_CODECID_VP6A:

  321.         if (flv_codecid == FLV_CODECID_VP6A)

  322.             par->codec_id = AV_CODEC_ID_VP6A;

  323.         if (read) {

  324.             if (par->extradata_size != 1) {

  325.                 ff_alloc_extradata(par, 1);

  326.             }

  327.             if (par->extradata)

  328.                 par->extradata[0] = avio_r8(s->pb);

  329.             else

  330.                 avio_skip(s->pb, 1);

  331.         }

  332.         ret = 1;     // 1 byte body size adjustment for flv_read_packet()

  333.         break;

  334.     case FLV_CODECID_H264:

  335.         par->codec_id = AV_CODEC_ID_H264;

  336.         vstream->need_parsing = AVSTREAM_PARSE_HEADERS;

  337.         ret = 3;     // not 4, reading packet type will consume one byte

  338.         break;

  339.     case FLV_CODECID_MPEG4:

  340.         par->codec_id = AV_CODEC_ID_MPEG4;

  341.         ret = 3;

  342.         break;

  343.     default:

  344.         avpriv_request_sample(s, "Video codec (%x)", flv_codecid);

  345.         par->codec_tag = flv_codecid;

  346.     }

  347. 

  348.     if (!vstream->internal->need_context_update && par->codec_id != old_codec_id) {

  349.         avpriv_request_sample(s, "Changing the codec id midstream");

  350.         return AVERROR_PATCHWELCOME;

  351.     }

  352. 

  353.     return ret;

  354. }

  355. 

  356. static int amf_get_string(AVIOContext *ioc, char *buffer, int buffsize)

  357. {

  358.     int length = avio_rb16(ioc);

  359.     if (length >= buffsize) {

  360.         avio_skip(ioc, length);

  361.         return -1;

  362.     }

  363. 

  364.     avio_read(ioc, buffer, length);

  365. 

  366.     buffer[length] = '\0';

  367. 

  368.     return length;

  369. }

  370. 

  371. static int parse_keyframes_index(AVFormatContext *s, AVIOContext *ioc, int64_t max_pos)

  372. {

  373.     FLVContext *flv       = s->priv_data;

  374.     unsigned int timeslen = 0, fileposlen = 0, i;

  375.     char str_val[256];

  376.     int64_t *times         = NULL;

  377.     int64_t *filepositions = NULL;

  378.     int ret                = AVERROR(ENOSYS);

  379.     int64_t initial_pos    = avio_tell(ioc);

  380. 

  381.     if (flv->keyframe_count > 0) {

  382.         av_log(s, AV_LOG_DEBUG, "keyframes have been paresed\n");

  383.         return 0;

  384.     }

  385.     av_assert0(!flv->keyframe_times);

  386.     av_assert0(!flv->keyframe_filepositions);

  387. 

  388.     if (s->flags & AVFMT_FLAG_IGNIDX)

  389.         return 0;

  390. 

  391.     while (avio_tell(ioc) < max_pos - 2 &&

  392.            amf_get_string(ioc, str_val, sizeof(str_val)) > 0) {

  393.         int64_t **current_array;

  394.         unsigned int arraylen;

  395. 

  396.         // Expect array object in context

  397.         if (avio_r8(ioc) != AMF_DATA_TYPE_ARRAY)

  398.             break;

  399. 

  400.         arraylen = avio_rb32(ioc);

  401.         if (arraylen>>28)

  402.             break;

  403. 

  404.         if       (!strcmp(KEYFRAMES_TIMESTAMP_TAG , str_val) && !times) {

  405.             current_array = &times;

  406.             timeslen      = arraylen;

  407.         } else if (!strcmp(KEYFRAMES_BYTEOFFSET_TAG, str_val) &&

  408.                    !filepositions) {

  409.             current_array = &filepositions;

  410.             fileposlen    = arraylen;

  411.         } else

  412.             // unexpected metatag inside keyframes, will not use such

  413.             // metadata for indexing

  414.             break;

  415. 

  416.         if (!(*current_array = av_mallocz(sizeof(**current_array) * arraylen))) {

  417.             ret = AVERROR(ENOMEM);

  418.             goto finish;

  419.         }

  420. 

  421.         for (i = 0; i < arraylen && avio_tell(ioc) < max_pos - 1; i++) {

  422.             if (avio_r8(ioc) != AMF_DATA_TYPE_NUMBER)

  423.                 goto invalid;

  424.             current_array[0][i] = av_int2double(avio_rb64(ioc));

  425.         }

  426.         if (times && filepositions) {

  427.             // All done, exiting at a position allowing amf_parse_object

  428.             // to finish parsing the object

  429.             ret = 0;

  430.             break;

  431.         }

  432.     }

  433. 

  434.     if (timeslen == fileposlen && fileposlen>1 && max_pos <= filepositions[0]) {

  435.         for (i = 0; i < FFMIN(2,fileposlen); i++) {

  436.             flv->validate_index[i].pos = filepositions[i];

  437.             flv->validate_index[i].dts = times[i] * 1000;

  438.             flv->validate_count        = i + 1;

  439.         }

  440.         flv->keyframe_times = times;

  441.         flv->keyframe_filepositions = filepositions;

  442.         flv->keyframe_count = timeslen;

  443.         times = NULL;

  444.         filepositions = NULL;

  445.     } else {

  446. invalid:

  447.         av_log(s, AV_LOG_WARNING, "Invalid keyframes object, skipping.\n");

  448.     }

  449. 

  450. finish:

  451.     av_freep(&times);

  452.     av_freep(&filepositions);

  453.     avio_seek(ioc, initial_pos, SEEK_SET);

  454.     return ret;

  455. }

  456. 

  457. static int amf_parse_object(AVFormatContext *s, AVStream *astream,

  458.                             AVStream *vstream, const char *key,

  459.                             int64_t max_pos, int depth)

  460. {

  461.     AVCodecParameters *apar, *vpar;

  462.     FLVContext *flv = s->priv_data;

  463.     AVIOContext *ioc;

  464.     AMFDataType amf_type;

  465.     char str_val[1024];

  466.     double num_val;

  467. 

  468.     num_val  = 0;

  469.     ioc      = s->pb;

  470.     amf_type = avio_r8(ioc);

  471. 

  472.     switch (amf_type) {

  473.     case AMF_DATA_TYPE_NUMBER:

  474.         num_val = av_int2double(avio_rb64(ioc));

  475.         break;

  476.     case AMF_DATA_TYPE_BOOL:

  477.         num_val = avio_r8(ioc);

  478.         break;

  479.     case AMF_DATA_TYPE_STRING:

  480.         if (amf_get_string(ioc, str_val, sizeof(str_val)) < 0) {

  481.             av_log(s, AV_LOG_ERROR, "AMF_DATA_TYPE_STRING parsing failed\n");

  482.             return -1;

  483.         }

  484.         break;

  485.     case AMF_DATA_TYPE_OBJECT:

  486.         if (key &&

  487.             ioc->seekable &&

  488.             !strcmp(KEYFRAMES_TAG, key) && depth == 1)

  489.             if (parse_keyframes_index(s, ioc,

  490.                                       max_pos) < 0)

  491.                 av_log(s, AV_LOG_ERROR, "Keyframe index parsing failed\n");

  492.             else

  493.                 add_keyframes_index(s);

  494.         while (avio_tell(ioc) < max_pos - 2 &&

  495.                amf_get_string(ioc, str_val, sizeof(str_val)) > 0)

  496.             if (amf_parse_object(s, astream, vstream, str_val, max_pos,

  497.                                  depth + 1) < 0)

  498.                 return -1;     // if we couldn't skip, bomb out.

  499.         if (avio_r8(ioc) != AMF_END_OF_OBJECT) {

  500.             av_log(s, AV_LOG_ERROR, "Missing AMF_END_OF_OBJECT in AMF_DATA_TYPE_OBJECT\n");

  501.             return -1;

  502.         }

  503.         break;

  504.     case AMF_DATA_TYPE_NULL:

  505.     case AMF_DATA_TYPE_UNDEFINED:

  506.     case AMF_DATA_TYPE_UNSUPPORTED:

  507.         break;     // these take up no additional space

  508.     case AMF_DATA_TYPE_MIXEDARRAY:

  509.     {

  510.         unsigned v;

  511.         avio_skip(ioc, 4);     // skip 32-bit max array index

  512.         while (avio_tell(ioc) < max_pos - 2 &&

  513.                amf_get_string(ioc, str_val, sizeof(str_val)) > 0)

  514.             // this is the only case in which we would want a nested

  515.             // parse to not skip over the object

  516.             if (amf_parse_object(s, astream, vstream, str_val, max_pos,

  517.                                  depth + 1) < 0)

  518.                 return -1;

  519.         v = avio_r8(ioc);

  520.         if (v != AMF_END_OF_OBJECT) {

  521.             av_log(s, AV_LOG_ERROR, "Missing AMF_END_OF_OBJECT in AMF_DATA_TYPE_MIXEDARRAY, found %d\n", v);

  522.             return -1;

  523.         }

  524.         break;

  525.     }

  526.     case AMF_DATA_TYPE_ARRAY:

  527.     {

  528.         unsigned int arraylen, i;

  529. 

  530.         arraylen = avio_rb32(ioc);

  531.         for (i = 0; i < arraylen && avio_tell(ioc) < max_pos - 1; i++)

  532.             if (amf_parse_object(s, NULL, NULL, NULL, max_pos,

  533.                                  depth + 1) < 0)

  534.                 return -1;      // if we couldn't skip, bomb out.

  535.     }

  536.     break;

  537.     case AMF_DATA_TYPE_DATE:

  538.         avio_skip(ioc, 8 + 2);  // timestamp (double) and UTC offset (int16)

  539.         break;

  540.     default:                    // unsupported type, we couldn't skip

  541.         av_log(s, AV_LOG_ERROR, "unsupported amf type %d\n", amf_type);

  542.         return -1;

  543.     }

  544. 

  545.     if (key) {

  546.         apar = astream ? astream->codecpar : NULL;

  547.         vpar = vstream ? vstream->codecpar : NULL;

  548. 

  549.         // stream info doesn't live any deeper than the first object

  550.         if (depth == 1) {

  551.             if (amf_type == AMF_DATA_TYPE_NUMBER ||

  552.                 amf_type == AMF_DATA_TYPE_BOOL) {

  553.                 if (!strcmp(key, "duration"))

  554.                     s->duration = num_val * AV_TIME_BASE;

  555.                 else if (!strcmp(key, "videodatarate") &&

  556.                          0 <= (int)(num_val * 1024.0))

  557.                     flv->video_bit_rate = num_val * 1024.0;

  558.                 else if (!strcmp(key, "audiodatarate") &&

  559.                          0 <= (int)(num_val * 1024.0))

  560.                     flv->audio_bit_rate = num_val * 1024.0;

  561.                 else if (!strcmp(key, "datastream")) {

  562.                     AVStream *st = create_stream(s, AVMEDIA_TYPE_SUBTITLE);

  563.                     if (!st)

  564.                         return AVERROR(ENOMEM);

  565.                     st->codecpar->codec_id = AV_CODEC_ID_TEXT;

  566.                 } else if (!strcmp(key, "framerate")) {

  567.                     flv->framerate = av_d2q(num_val, 1000);

  568.                     if (vstream)

  569.                         vstream->avg_frame_rate = flv->framerate;

  570.                 } else if (flv->trust_metadata) {

  571.                     if (!strcmp(key, "videocodecid") && vpar) {

  572.                         int ret = flv_set_video_codec(s, vstream, num_val, 0);

  573.                         if (ret < 0)

  574.                             return ret;

  575.                     } else if (!strcmp(key, "audiocodecid") && apar) {

  576.                         int id = ((int)num_val) << FLV_AUDIO_CODECID_OFFSET;

  577.                         flv_set_audio_codec(s, astream, apar, id);

  578.                     } else if (!strcmp(key, "audiosamplerate") && apar) {

  579.                         apar->sample_rate = num_val;

  580.                     } else if (!strcmp(key, "audiosamplesize") && apar) {

  581.                         apar->bits_per_coded_sample = num_val;

  582.                     } else if (!strcmp(key, "stereo") && apar) {

  583.                         apar->channels       = num_val + 1;

  584.                         apar->channel_layout = apar->channels == 2 ?

  585.                                                AV_CH_LAYOUT_STEREO :

  586.                                                AV_CH_LAYOUT_MONO;

  587.                     } else if (!strcmp(key, "width") && vpar) {

  588.                         vpar->width = num_val;

  589.                     } else if (!strcmp(key, "height") && vpar) {

  590.                         vpar->height = num_val;

  591.                     }

  592.                 }

  593.             }

  594.             if (amf_type == AMF_DATA_TYPE_STRING) {

  595.                 if (!strcmp(key, "encoder")) {

  596.                     int version = -1;

  597.                     if (1 == sscanf(str_val, "Open Broadcaster Software v0.%d", &version)) {

  598.                         if (version > 0 && version <= 655)

  599.                             flv->broken_sizes = 1;

  600.                     }

  601.                 } else if (!strcmp(key, "metadatacreator") && !strcmp(str_val, "MEGA")) {

  602.                     flv->broken_sizes = 1;

  603.                 }

  604.             }

  605.         }

  606. 

  607.         if (amf_type == AMF_DATA_TYPE_OBJECT && s->nb_streams == 1 &&

  608.            ((!apar && !strcmp(key, "audiocodecid")) ||

  609.             (!vpar && !strcmp(key, "videocodecid"))))

  610.                 s->ctx_flags &= ~AVFMTCTX_NOHEADER; //If there is either audio/video missing, codecid will be an empty object

  611. 

  612.         if (!strcmp(key, "duration")        ||

  613.             !strcmp(key, "filesize")        ||

  614.             !strcmp(key, "width")           ||

  615.             !strcmp(key, "height")          ||

  616.             !strcmp(key, "videodatarate")   ||

  617.             !strcmp(key, "framerate")       ||

  618.             !strcmp(key, "videocodecid")    ||

  619.             !strcmp(key, "audiodatarate")   ||

  620.             !strcmp(key, "audiosamplerate") ||

  621.             !strcmp(key, "audiosamplesize") ||

  622.             !strcmp(key, "stereo")          ||

  623.             !strcmp(key, "audiocodecid")    ||

  624.             !strcmp(key, "datastream"))

  625.             return 0;

  626. 

  627.         s->event_flags |= AVFMT_EVENT_FLAG_METADATA_UPDATED;

  628.         if (amf_type == AMF_DATA_TYPE_BOOL) {

  629.             av_strlcpy(str_val, num_val > 0 ? "true" : "false",

  630.                        sizeof(str_val));

  631.             av_dict_set(&s->metadata, key, str_val, 0);

  632.         } else if (amf_type == AMF_DATA_TYPE_NUMBER) {

  633.             snprintf(str_val, sizeof(str_val), "%.f", num_val);

  634.             av_dict_set(&s->metadata, key, str_val, 0);

  635.         } else if (amf_type == AMF_DATA_TYPE_STRING)

  636.             av_dict_set(&s->metadata, key, str_val, 0);

  637.     }

  638. 

  639.     return 0;

  640. }

  641. 

  642. #define TYPE_ONTEXTDATA 1

  643. #define TYPE_ONCAPTION 2

  644. #define TYPE_ONCAPTIONINFO 3

  645. #define TYPE_UNKNOWN 9

  646. 

  647. static int flv_read_metabody(AVFormatContext *s, int64_t next_pos)

  648. {

  649.     FLVContext *flv = s->priv_data;

  650.     AMFDataType type;

  651.     AVStream *stream, *astream, *vstream;

  652.     AVStream av_unused *dstream;

  653.     AVIOContext *ioc;

  654.     int i;

  655.     // only needs to hold the string "onMetaData".

  656.     // Anything longer is something we don't want.

  657.     char buffer[32];

  658. 

  659.     astream = NULL;

  660.     vstream = NULL;

  661.     dstream = NULL;

  662.     ioc     = s->pb;

  663. 

  664.     // first object needs to be "onMetaData" string

  665.     type = avio_r8(ioc);

  666.     if (type != AMF_DATA_TYPE_STRING ||

  667.         amf_get_string(ioc, buffer, sizeof(buffer)) < 0)

  668.         return TYPE_UNKNOWN;

  669. 

  670.     if (!strcmp(buffer, "onTextData"))

  671.         return TYPE_ONTEXTDATA;

  672. 

  673.     if (!strcmp(buffer, "onCaption"))

  674.         return TYPE_ONCAPTION;

  675. 

  676.     if (!strcmp(buffer, "onCaptionInfo"))

  677.         return TYPE_ONCAPTIONINFO;

  678. 

  679.     if (strcmp(buffer, "onMetaData") && strcmp(buffer, "onCuePoint")) {

  680.         av_log(s, AV_LOG_DEBUG, "Unknown type %s\n", buffer);

  681.         return TYPE_UNKNOWN;

  682.     }

  683. 

  684.     // find the streams now so that amf_parse_object doesn't need to do

  685.     // the lookup every time it is called.

  686.     for (i = 0; i < s->nb_streams; i++) {

  687.         stream = s->streams[i];

  688.         if (stream->codecpar->codec_type == AVMEDIA_TYPE_VIDEO) {

  689.             vstream = stream;

  690.             flv->last_keyframe_stream_index = i;

  691.         } else if (stream->codecpar->codec_type == AVMEDIA_TYPE_AUDIO) {

  692.             astream = stream;

  693.             if (flv->last_keyframe_stream_index == -1)

  694.                 flv->last_keyframe_stream_index = i;

  695.         }

  696.         else if (stream->codecpar->codec_type == AVMEDIA_TYPE_SUBTITLE)

  697.             dstream = stream;

  698.     }

  699. 

  700.     // parse the second object (we want a mixed array)

  701.     if (amf_parse_object(s, astream, vstream, buffer, next_pos, 0) < 0)

  702.         return -1;

  703. 

  704.     return 0;

  705. }

  706. 

  707. static int flv_read_header(AVFormatContext *s)

  708. {

  709.     int flags;

  710.     FLVContext *flv = s->priv_data;

  711.     int offset;

  712. 

  713.     avio_skip(s->pb, 4);

  714.     flags = avio_r8(s->pb);

  715. 

  716.     flv->missing_streams = flags & (FLV_HEADER_FLAG_HASVIDEO | FLV_HEADER_FLAG_HASAUDIO);

  717. 

  718.     s->ctx_flags |= AVFMTCTX_NOHEADER;

  719. 

  720.     offset = avio_rb32(s->pb);

  721.     avio_seek(s->pb, offset, SEEK_SET);

  722.     avio_skip(s->pb, 4);

  723. 

  724.     s->start_time = 0;

  725.     flv->sum_flv_tag_size = 0;

  726.     flv->last_keyframe_stream_index = -1;

  727. 

  728.     return 0;

  729. }

  730. 

  731. static int flv_read_close(AVFormatContext *s)

  732. {

  733.     int i;

  734.     FLVContext *flv = s->priv_data;

  735.     for (i=0; i<FLV_STREAM_TYPE_NB; i++)

  736.         av_freep(&flv->new_extradata[i]);

  737.     av_freep(&flv->keyframe_times);

  738.     av_freep(&flv->keyframe_filepositions);

  739.     return 0;

  740. }

  741. 

  742. static int flv_get_extradata(AVFormatContext *s, AVStream *st, int size)

  743. {

  744.     av_freep(&st->codecpar->extradata);

  745.     if (ff_get_extradata(s, st->codecpar, s->pb, size) < 0)

  746.         return AVERROR(ENOMEM);

  747.     return 0;

  748. }

  749. 

  750. static int flv_queue_extradata(FLVContext *flv, AVIOContext *pb, int stream,

  751.                                int size)

  752. {

  753.     av_free(flv->new_extradata[stream]);

  754.     flv->new_extradata[stream] = av_mallocz(size +

  755.                                             AV_INPUT_BUFFER_PADDING_SIZE);

  756.     if (!flv->new_extradata[stream])

  757.         return AVERROR(ENOMEM);

  758.     flv->new_extradata_size[stream] = size;

  759.     avio_read(pb, flv->new_extradata[stream], size);

  760.     return 0;

  761. }

  762. 

  763. static void clear_index_entries(AVFormatContext *s, int64_t pos)

  764. {

  765.     int i, j, out;

  766.     av_log(s, AV_LOG_WARNING,

  767.            "Found invalid index entries, clearing the index.\n");

  768.     for (i = 0; i < s->nb_streams; i++) {

  769.         AVStream *st = s->streams[i];

  770.         /* Remove all index entries that point to >= pos */

  771.         out = 0;

  772.         for (j = 0; j < st->nb_index_entries; j++)

  773.             if (st->index_entries[j].pos < pos)

  774.                 st->index_entries[out++] = st->index_entries[j];

  775.         st->nb_index_entries = out;

  776.     }

  777. }

  778. 

  779. static int amf_skip_tag(AVIOContext *pb, AMFDataType type)

  780. {

  781.     int nb = -1, ret, parse_name = 1;

  782. 

  783.     switch (type) {

  784.     case AMF_DATA_TYPE_NUMBER:

  785.         avio_skip(pb, 8);

  786.         break;

  787.     case AMF_DATA_TYPE_BOOL:

  788.         avio_skip(pb, 1);

  789.         break;

  790.     case AMF_DATA_TYPE_STRING:

  791.         avio_skip(pb, avio_rb16(pb));

  792.         break;

  793.     case AMF_DATA_TYPE_ARRAY:

  794.         parse_name = 0;

  795.     case AMF_DATA_TYPE_MIXEDARRAY:

  796.         nb = avio_rb32(pb);

  797.     case AMF_DATA_TYPE_OBJECT:

  798.         while(!pb->eof_reached && (nb-- > 0 || type != AMF_DATA_TYPE_ARRAY)) {

  799.             if (parse_name) {

  800.                 int size = avio_rb16(pb);

  801.                 if (!size) {

  802.                     avio_skip(pb, 1);

  803.                     break;

  804.                 }

  805.                 avio_skip(pb, size);

  806.             }

  807.             if ((ret = amf_skip_tag(pb, avio_r8(pb))) < 0)

  808.                 return ret;

  809.         }

  810.         break;

  811.     case AMF_DATA_TYPE_NULL:

  812.     case AMF_DATA_TYPE_OBJECT_END:

  813.         break;

  814.     default:

  815.         return AVERROR_INVALIDDATA;

  816.     }

  817.     return 0;

  818. }

  819. 

  820. static int flv_data_packet(AVFormatContext *s, AVPacket *pkt,

  821.                            int64_t dts, int64_t next)

  822. {

  823.     AVIOContext *pb = s->pb;

  824.     AVStream *st    = NULL;

  825.     char buf[20];

  826.     int ret = AVERROR_INVALIDDATA;

  827.     int i, length = -1;

  828.     int array = 0;

  829. 

  830.     switch (avio_r8(pb)) {

  831.     case AMF_DATA_TYPE_ARRAY:

  832.         array = 1;

  833.     case AMF_DATA_TYPE_MIXEDARRAY:

  834.         avio_seek(pb, 4, SEEK_CUR);

  835.     case AMF_DATA_TYPE_OBJECT:

  836.         break;

  837.     default:

  838.         goto skip;

  839.     }

  840. 

  841.     while (array || (ret = amf_get_string(pb, buf, sizeof(buf))) > 0) {

  842.         AMFDataType type = avio_r8(pb);

  843.         if (type == AMF_DATA_TYPE_STRING && (array || !strcmp(buf, "text"))) {

  844.             length = avio_rb16(pb);

  845.             ret    = av_get_packet(pb, pkt, length);

  846.             if (ret < 0)

  847.                 goto skip;

  848.             else

  849.                 break;

  850.         } else {

  851.             if ((ret = amf_skip_tag(pb, type)) < 0)

  852.                 goto skip;

  853.         }

  854.     }

  855. 

  856.     if (length < 0) {

  857.         ret = AVERROR_INVALIDDATA;

  858.         goto skip;

  859.     }

  860. 

  861.     for (i = 0; i < s->nb_streams; i++) {

  862.         st = s->streams[i];

  863.         if (st->codecpar->codec_type == AVMEDIA_TYPE_SUBTITLE)

  864.             break;

  865.     }

  866. 

  867.     if (i == s->nb_streams) {

  868.         st = create_stream(s, AVMEDIA_TYPE_SUBTITLE);

  869.         if (!st)

  870.             return AVERROR(ENOMEM);

  871.         st->codecpar->codec_id = AV_CODEC_ID_TEXT;

  872.     }

  873. 

  874.     pkt->dts  = dts;

  875.     pkt->pts  = dts;

  876.     pkt->size = ret;

  877. 

  878.     pkt->stream_index = st->index;

  879.     pkt->flags       |= AV_PKT_FLAG_KEY;

  880. 

  881. skip:

  882.     avio_seek(s->pb, next + 4, SEEK_SET);

  883. 

  884.     return ret;

  885. }

  886. 

  887. static int resync(AVFormatContext *s)

  888. {

  889.     FLVContext *flv = s->priv_data;

  890.     int64_t i;

  891.     int64_t pos = avio_tell(s->pb);

  892. 

  893.     for (i=0; !avio_feof(s->pb); i++) {

  894.         int j  = i & (RESYNC_BUFFER_SIZE-1);

  895.         int j1 = j + RESYNC_BUFFER_SIZE;

  896.         flv->resync_buffer[j ] =

  897.         flv->resync_buffer[j1] = avio_r8(s->pb);

  898. 

  899.         if (i > 22) {

  900.             unsigned lsize2 = AV_RB32(flv->resync_buffer + j1 - 4);

  901.             if (lsize2 >= 11 && lsize2 + 8LL < FFMIN(i, RESYNC_BUFFER_SIZE)) {

  902.                 unsigned  size2 = AV_RB24(flv->resync_buffer + j1 - lsize2 + 1 - 4);

  903.                 unsigned lsize1 = AV_RB32(flv->resync_buffer + j1 - lsize2 - 8);

  904.                 if (lsize1 >= 11 && lsize1 + 8LL + lsize2 < FFMIN(i, RESYNC_BUFFER_SIZE)) {

  905.                     unsigned  size1 = AV_RB24(flv->resync_buffer + j1 - lsize1 + 1 - lsize2 - 8);

  906.                     if (size1 == lsize1 - 11 && size2  == lsize2 - 11) {

  907.                         avio_seek(s->pb, pos + i - lsize1 - lsize2 - 8, SEEK_SET);

  908.                         return 1;

  909.                     }

  910.                 }

  911.             }

  912.         }

  913.     }

  914.     return AVERROR_EOF;

  915. }

  916. 

  917. static int flv_read_packet(AVFormatContext *s, AVPacket *pkt)

  918. {

  919.     FLVContext *flv = s->priv_data;

  920.     int ret, i, size, flags;

  921.     enum FlvTagType type;

  922.     int stream_type=-1;

  923.     int64_t next, pos, meta_pos;

  924.     int64_t dts, pts = AV_NOPTS_VALUE;

  925.     int av_uninit(channels);

  926.     int av_uninit(sample_rate);

  927.     AVStream *st    = NULL;

  928.     int last = -1;

  929.     int orig_size;

  930. 

  931. retry:

  932.     /* pkt size is repeated at end. skip it */

  933.         pos  = avio_tell(s->pb);

  934.         type = (avio_r8(s->pb) & 0x1F);

  935.         orig_size =

  936.         size = avio_rb24(s->pb);

  937.         flv->sum_flv_tag_size += size + 11;

  938.         dts  = avio_rb24(s->pb);

  939.         dts |= (unsigned)avio_r8(s->pb) << 24;

  940.         av_log(s, AV_LOG_TRACE, "type:%d, size:%d, last:%d, dts:%"PRId64" pos:%"PRId64"\n", type, size, last, dts, avio_tell(s->pb));

  941.         if (avio_feof(s->pb))

  942.             return AVERROR_EOF;

  943.         avio_skip(s->pb, 3); /* stream id, always 0 */

  944.         flags = 0;

  945. 

  946.         if (flv->validate_next < flv->validate_count) {

  947.             int64_t validate_pos = flv->validate_index[flv->validate_next].pos;

  948.             if (pos == validate_pos) {

  949.                 if (FFABS(dts - flv->validate_index[flv->validate_next].dts) <=

  950.                     VALIDATE_INDEX_TS_THRESH) {

  951.                     flv->validate_next++;

  952.                 } else {

  953.                     clear_index_entries(s, validate_pos);

  954.                     flv->validate_count = 0;

  955.                 }

  956.             } else if (pos > validate_pos) {

  957.                 clear_index_entries(s, validate_pos);

  958.                 flv->validate_count = 0;

  959.             }

  960.         }

  961. 

  962.         if (size == 0) {

  963.             ret = FFERROR_REDO;

  964.             goto leave;

  965.         }

  966. 

  967.         next = size + avio_tell(s->pb);

  968. 

  969.         if (type == FLV_TAG_TYPE_AUDIO) {

  970.             stream_type = FLV_STREAM_TYPE_AUDIO;

  971.             flags    = avio_r8(s->pb);

  972.             size--;

  973.         } else if (type == FLV_TAG_TYPE_VIDEO) {

  974.             stream_type = FLV_STREAM_TYPE_VIDEO;

  975.             flags    = avio_r8(s->pb);

  976.             size--;

  977.             if ((flags & FLV_VIDEO_FRAMETYPE_MASK) == FLV_FRAME_VIDEO_INFO_CMD)

  978.                 goto skip;

  979.         } else if (type == FLV_TAG_TYPE_META) {

  980.             stream_type=FLV_STREAM_TYPE_DATA;

  981.             if (size > 13 + 1 + 4) { // Header-type metadata stuff

  982.                 int type;

  983.                 meta_pos = avio_tell(s->pb);

  984.                 type = flv_read_metabody(s, next);

  985.                 if (type == 0 && dts == 0 || type < 0 || type == TYPE_UNKNOWN) {

  986.                     if (type < 0 && flv->validate_count &&

  987.                         flv->validate_index[0].pos     > next &&

  988.                         flv->validate_index[0].pos - 4 < next

  989.                     ) {

  990.                         av_log(s, AV_LOG_WARNING, "Adjusting next position due to index mismatch\n");

  991.                         next = flv->validate_index[0].pos - 4;

  992.                     }

  993.                     goto skip;

  994.                 } else if (type == TYPE_ONTEXTDATA) {

  995.                     avpriv_request_sample(s, "OnTextData packet");

  996.                     return flv_data_packet(s, pkt, dts, next);

  997.                 } else if (type == TYPE_ONCAPTION) {

  998.                     return flv_data_packet(s, pkt, dts, next);

  999.                 }

  1000.                 avio_seek(s->pb, meta_pos, SEEK_SET);

  1001.             }

  1002.         } else {

  1003.             av_log(s, AV_LOG_DEBUG,

  1004.                    "Skipping flv packet: type %d, size %d, flags %d.\n",

  1005.                    type, size, flags);

  1006. skip:

  1007.             avio_seek(s->pb, next, SEEK_SET);

  1008.             ret = FFERROR_REDO;

  1009.             goto leave;

  1010.         }

  1011. 

  1012.         /* skip empty data packets */

  1013.         if (!size) {

  1014.             ret = FFERROR_REDO;

  1015.             goto leave;

  1016.         }

  1017. 

  1018.         /* now find stream */

  1019.         for (i = 0; i < s->nb_streams; i++) {

  1020.             st = s->streams[i];

  1021.             if (stream_type == FLV_STREAM_TYPE_AUDIO) {

  1022.                 if (st->codecpar->codec_type == AVMEDIA_TYPE_AUDIO &&

  1023.                     (s->audio_codec_id || flv_same_audio_codec(st->codecpar, flags)))

  1024.                     break;

  1025.             } else if (stream_type == FLV_STREAM_TYPE_VIDEO) {

  1026.                 if (st->codecpar->codec_type == AVMEDIA_TYPE_VIDEO &&

  1027.                     (s->video_codec_id || flv_same_video_codec(st->codecpar, flags)))

  1028.                     break;

  1029.             } else if (stream_type == FLV_STREAM_TYPE_DATA) {

  1030.                 if (st->codecpar->codec_type == AVMEDIA_TYPE_SUBTITLE)

  1031.                     break;

  1032.             }

  1033.         }

  1034.         if (i == s->nb_streams) {

  1035.             static const enum AVMediaType stream_types[] = {AVMEDIA_TYPE_VIDEO, AVMEDIA_TYPE_AUDIO, AVMEDIA_TYPE_SUBTITLE};

  1036.             st = create_stream(s, stream_types[stream_type]);

  1037.             if (!st)

  1038.                 return AVERROR(ENOMEM);

  1039. 

  1040.         }

  1041.         av_log(s, AV_LOG_TRACE, "%d %X %d \n", stream_type, flags, st->discard);

  1042. 

  1043.         if (s->pb->seekable &&

  1044.             ((flags & FLV_VIDEO_FRAMETYPE_MASK) == FLV_FRAME_KEY ||

  1045.               stream_type == FLV_STREAM_TYPE_AUDIO))

  1046.             av_add_index_entry(st, pos, dts, size, 0, AVINDEX_KEYFRAME);

  1047. 

  1048.         if (  (st->discard >= AVDISCARD_NONKEY && !((flags & FLV_VIDEO_FRAMETYPE_MASK) == FLV_FRAME_KEY || (stream_type == FLV_STREAM_TYPE_AUDIO)))

  1049.             ||(st->discard >= AVDISCARD_BIDIR  &&  ((flags & FLV_VIDEO_FRAMETYPE_MASK) == FLV_FRAME_DISP_INTER && (stream_type == FLV_STREAM_TYPE_VIDEO)))

  1050.             || st->discard >= AVDISCARD_ALL

  1051.         ) {

  1052.             avio_seek(s->pb, next, SEEK_SET);

  1053.             ret = FFERROR_REDO;

  1054.             goto leave;

  1055.         }

  1056. 

  1057.     // if not streamed and no duration from metadata then seek to end to find

  1058.     // the duration from the timestamps

  1059.     if (s->pb->seekable && (!s->duration || s->duration == AV_NOPTS_VALUE) &&

  1060.         !flv->searched_for_end) {

  1061.         int size;

  1062.         const int64_t pos   = avio_tell(s->pb);

  1063.         // Read the last 4 bytes of the file, this should be the size of the

  1064.         // previous FLV tag. Use the timestamp of its payload as duration.

  1065.         int64_t fsize       = avio_size(s->pb);

  1066. retry_duration:

  1067.         avio_seek(s->pb, fsize - 4, SEEK_SET);

  1068.         size = avio_rb32(s->pb);

  1069.         if (size > 0 && size < fsize) {

  1070.             // Seek to the start of the last FLV tag at position (fsize - 4 - size)

  1071.             // but skip the byte indicating the type.

  1072.             avio_seek(s->pb, fsize - 3 - size, SEEK_SET);

  1073.             if (size == avio_rb24(s->pb) + 11) {

  1074.                 uint32_t ts = avio_rb24(s->pb);

  1075.                 ts         |= avio_r8(s->pb) << 24;

  1076.                 if (ts)

  1077.                     s->duration = ts * (int64_t)AV_TIME_BASE / 1000;

  1078.                 else if (fsize >= 8 && fsize - 8 >= size) {

  1079.                     fsize -= size+4;

  1080.                     goto retry_duration;

  1081.                 }

  1082.             }

  1083.         }

  1084. 

  1085.         avio_seek(s->pb, pos, SEEK_SET);

  1086.         flv->searched_for_end = 1;

  1087.     }

  1088. 

  1089.     if (stream_type == FLV_STREAM_TYPE_AUDIO) {

  1090.         int bits_per_coded_sample;

  1091.         channels = (flags & FLV_AUDIO_CHANNEL_MASK) == FLV_STEREO ? 2 : 1;

  1092.         sample_rate = 44100 << ((flags & FLV_AUDIO_SAMPLERATE_MASK) >>

  1093.                                 FLV_AUDIO_SAMPLERATE_OFFSET) >> 3;

  1094.         bits_per_coded_sample = (flags & FLV_AUDIO_SAMPLESIZE_MASK) ? 16 : 8;

  1095.         if (!st->codecpar->channels || !st->codecpar->sample_rate ||

  1096.             !st->codecpar->bits_per_coded_sample) {

  1097.             st->codecpar->channels              = channels;

  1098.             st->codecpar->channel_layout        = channels == 1

  1099.                                                ? AV_CH_LAYOUT_MONO

  1100.                                                : AV_CH_LAYOUT_STEREO;

  1101.             st->codecpar->sample_rate           = sample_rate;

  1102.             st->codecpar->bits_per_coded_sample = bits_per_coded_sample;

  1103.         }

  1104.         if (!st->codecpar->codec_id) {

  1105.             flv_set_audio_codec(s, st, st->codecpar,

  1106.                                 flags & FLV_AUDIO_CODECID_MASK);

  1107.             flv->last_sample_rate =

  1108.             sample_rate           = st->codecpar->sample_rate;

  1109.             flv->last_channels    =

  1110.             channels              = st->codecpar->channels;

  1111.         } else {

  1112.             AVCodecParameters *par = avcodec_parameters_alloc();

  1113.             if (!par) {

  1114.                 ret = AVERROR(ENOMEM);

  1115.                 goto leave;

  1116.             }

  1117.             par->sample_rate = sample_rate;

  1118.             par->bits_per_coded_sample = bits_per_coded_sample;

  1119.             flv_set_audio_codec(s, st, par, flags & FLV_AUDIO_CODECID_MASK);

  1120.             sample_rate = par->sample_rate;

  1121.             avcodec_parameters_free(&par);

  1122.         }

  1123.     } else if (stream_type == FLV_STREAM_TYPE_VIDEO) {

  1124.         int ret = flv_set_video_codec(s, st, flags & FLV_VIDEO_CODECID_MASK, 1);

  1125.         if (ret < 0)

  1126.             return ret;

  1127.         size -= ret;

  1128.     } else if (stream_type == FLV_STREAM_TYPE_DATA) {

  1129.         st->codecpar->codec_id = AV_CODEC_ID_TEXT;

  1130.     }

  1131. 

  1132.     if (st->codecpar->codec_id == AV_CODEC_ID_AAC ||

  1133.         st->codecpar->codec_id == AV_CODEC_ID_H264 ||

  1134.         st->codecpar->codec_id == AV_CODEC_ID_MPEG4) {

  1135.         int type = avio_r8(s->pb);

  1136.         size--;

  1137.         if (st->codecpar->codec_id == AV_CODEC_ID_H264 || st->codecpar->codec_id == AV_CODEC_ID_MPEG4) {

  1138.             // sign extension

  1139.             int32_t cts = (avio_rb24(s->pb) + 0xff800000) ^ 0xff800000;

  1140.             pts = dts + cts;

  1141.             if (cts < 0) { // dts might be wrong

  1142.                 if (!flv->wrong_dts)

  1143.                     av_log(s, AV_LOG_WARNING,

  1144.                         "Negative cts, previous timestamps might be wrong.\n");

  1145.                 flv->wrong_dts = 1;

  1146.             } else if (FFABS(dts - pts) > 1000*60*15) {

  1147.                 av_log(s, AV_LOG_WARNING,

  1148.                        "invalid timestamps %"PRId64" %"PRId64"\n", dts, pts);

  1149.                 dts = pts = AV_NOPTS_VALUE;

  1150.             }

  1151.         }

  1152.         if (type == 0 && (!st->codecpar->extradata || st->codecpar->codec_id == AV_CODEC_ID_AAC ||

  1153.             st->codecpar->codec_id == AV_CODEC_ID_H264)) {

  1154.             AVDictionaryEntry *t;

  1155. 

  1156.             if (st->codecpar->extradata) {

  1157.                 if ((ret = flv_queue_extradata(flv, s->pb, stream_type, size)) < 0)

  1158.                     return ret;

  1159.                 ret = FFERROR_REDO;

  1160.                 goto leave;

  1161.             }

  1162.             if ((ret = flv_get_extradata(s, st, size)) < 0)

  1163.                 return ret;

  1164. 

  1165.             /* Workaround for buggy Omnia A/XE encoder */

  1166.             t = av_dict_get(s->metadata, "Encoder", NULL, 0);

  1167.             if (st->codecpar->codec_id == AV_CODEC_ID_AAC && t && !strcmp(t->value, "Omnia A/XE"))

  1168.                 st->codecpar->extradata_size = 2;

  1169. 

  1170.             if (st->codecpar->codec_id == AV_CODEC_ID_AAC && 0) {

  1171.                 MPEG4AudioConfig cfg;

  1172. 

  1173.                 if (avpriv_mpeg4audio_get_config(&cfg, st->codecpar->extradata,

  1174.                                                  st->codecpar->extradata_size * 8, 1) >= 0) {

  1175.                 st->codecpar->channels       = cfg.channels;

  1176.                 st->codecpar->channel_layout = 0;

  1177.                 if (cfg.ext_sample_rate)

  1178.                     st->codecpar->sample_rate = cfg.ext_sample_rate;

  1179.                 else

  1180.                     st->codecpar->sample_rate = cfg.sample_rate;

  1181.                 av_log(s, AV_LOG_TRACE, "mp4a config channels %d sample rate %d\n",

  1182.                         st->codecpar->channels, st->codecpar->sample_rate);

  1183.                 }

  1184.             }

  1185. 

  1186.             ret = FFERROR_REDO;

  1187.             goto leave;

  1188.         }

  1189.     }

  1190. 

  1191.     /* skip empty data packets */

  1192.     if (!size) {

  1193.         ret = FFERROR_REDO;

  1194.         goto leave;

  1195.     }

  1196. 

  1197.     ret = av_get_packet(s->pb, pkt, size);

  1198.     if (ret < 0)

  1199.         return ret;

  1200.     pkt->dts          = dts;

  1201.     pkt->pts          = pts == AV_NOPTS_VALUE ? dts : pts;

  1202.     pkt->stream_index = st->index;

  1203.     pkt->pos          = pos;

  1204.     if (flv->new_extradata[stream_type]) {

  1205.         uint8_t *side = av_packet_new_side_data(pkt, AV_PKT_DATA_NEW_EXTRADATA,

  1206.                                                 flv->new_extradata_size[stream_type]);

  1207.         if (side) {

  1208.             memcpy(side, flv->new_extradata[stream_type],

  1209.                    flv->new_extradata_size[stream_type]);

  1210.             av_freep(&flv->new_extradata[stream_type]);

  1211.             flv->new_extradata_size[stream_type] = 0;

  1212.         }

  1213.     }

  1214.     if (stream_type == FLV_STREAM_TYPE_AUDIO &&

  1215.                     (sample_rate != flv->last_sample_rate ||

  1216.                      channels    != flv->last_channels)) {

  1217.         flv->last_sample_rate = sample_rate;

  1218.         flv->last_channels    = channels;

  1219.         ff_add_param_change(pkt, channels, 0, sample_rate, 0, 0);

  1220.     }

  1221. 

  1222.     if (    stream_type == FLV_STREAM_TYPE_AUDIO ||

  1223.             ((flags & FLV_VIDEO_FRAMETYPE_MASK) == FLV_FRAME_KEY) ||

  1224.             stream_type == FLV_STREAM_TYPE_DATA)

  1225.         pkt->flags |= AV_PKT_FLAG_KEY;

  1226. 

  1227. leave:

  1228.     last = avio_rb32(s->pb);

  1229.     if (last != orig_size + 11 && last != orig_size + 10 &&

  1230.         !avio_feof(s->pb) &&

  1231.         (last != orig_size || !last) && last != flv->sum_flv_tag_size &&

  1232.         !flv->broken_sizes) {

  1233.         av_log(s, AV_LOG_ERROR, "Packet mismatch %d %d %d\n", last, orig_size + 11, flv->sum_flv_tag_size);

  1234.         avio_seek(s->pb, pos + 1, SEEK_SET);

  1235.         ret = resync(s);

  1236.         av_packet_unref(pkt);

  1237.         if (ret >= 0) {

  1238.             goto retry;

  1239.         }

  1240.     }

  1241.     return ret;

  1242. }

  1243. 

  1244. static int flv_read_seek(AVFormatContext *s, int stream_index,

  1245.                          int64_t ts, int flags)

  1246. {

  1247.     FLVContext *flv = s->priv_data;

  1248.     flv->validate_count = 0;

  1249.     return avio_seek_time(s->pb, stream_index, ts, flags);

  1250. }

  1251. 

  1252. #define OFFSET(x) offsetof(FLVContext, x)

  1253. #define VD AV_OPT_FLAG_VIDEO_PARAM | AV_OPT_FLAG_DECODING_PARAM

  1254. static const AVOption options[] = {

  1255.     { "flv_metadata", "Allocate streams according to the onMetaData array", OFFSET(trust_metadata), AV_OPT_TYPE_BOOL, { .i64 = 0 }, 0, 1, VD },

  1256.     { "missing_streams", "", OFFSET(missing_streams), AV_OPT_TYPE_INT, { .i64 = 0 }, 0, 0xFF, VD | AV_OPT_FLAG_EXPORT | AV_OPT_FLAG_READONLY },

  1257.     { NULL }

  1258. };

  1259. 

  1260. static const AVClass flv_class = {

  1261.     .class_name = "flvdec",

  1262.     .item_name  = av_default_item_name,

  1263.     .option     = options,

  1264.     .version    = LIBAVUTIL_VERSION_INT,

  1265. };

  1266. 

  1267. AVInputFormat ff_flv_demuxer = {

  1268.     .name           = "flv",

  1269.     .long_name      = NULL_IF_CONFIG_SMALL("FLV (Flash Video)"),

  1270.     .priv_data_size = sizeof(FLVContext),

  1271.     .read_probe     = flv_probe,

  1272.     .read_header    = flv_read_header,

  1273.     .read_packet    = flv_read_packet,

  1274.     .read_seek      = flv_read_seek,

  1275.     .read_close     = flv_read_close,

  1276.     .extensions     = "flv",

  1277.     .priv_class     = &flv_class,

  1278. };

  1279. 

  1280. static const AVClass live_flv_class = {

  1281.     .class_name = "live_flvdec",

  1282.     .item_name  = av_default_item_name,

  1283.     .option     = options,

  1284.     .version    = LIBAVUTIL_VERSION_INT,

  1285. };

  1286. 

  1287. AVInputFormat ff_live_flv_demuxer = {

  1288.     .name           = "live_flv",

  1289.     .long_name      = NULL_IF_CONFIG_SMALL("live RTMP FLV (Flash Video)"),

  1290.     .priv_data_size = sizeof(FLVContext),

  1291.     .read_probe     = live_flv_probe,

  1292.     .read_header    = flv_read_header,

  1293.     .read_packet    = flv_read_packet,

  1294.     .read_seek      = flv_read_seek,

  1295.     .read_close     = flv_read_close,

  1296.     .extensions     = "flv",

  1297.     .priv_class     = &live_flv_class,

  1298.     .flags          = AVFMT_TS_DISCONT

  1299. };