falkTX
/
FFmpeg
mirror of https://github.com/falkTX/FFmpeg.git
1
0
Fork 0
Code Issues 0 Releases 338 Wiki Activity
You can not select more than 25 topics Topics must start with a letter or number, can include dashes ('-') and can be up to 35 characters long.
60535 Commits
32 Branches
766MB
Tree: dcda5ef1ea
Branches Tags
${ item.name }
Create branch ${ searchTerm }
from 'dcda5ef1ea'
${ noResults }
FFmpeg/libavformat/avidec.c

1743 lines
59KB
Raw Blame History 

  1. /*

  2.  * AVI demuxer

  3.  * Copyright (c) 2001 Fabrice Bellard

  4.  *

  5.  * This file is part of FFmpeg.

  6.  *

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

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

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

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

  11.  *

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

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

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

  15.  * Lesser General Public License for more details.

  16.  *

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

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

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

  20.  */

  21. 

  22. #include <stdint.h>

  23. 

  24. #include "libavutil/avassert.h"

  25. #include "libavutil/avstring.h"

  26. #include "libavutil/bswap.h"

  27. #include "libavutil/opt.h"

  28. #include "libavutil/dict.h"

  29. #include "libavutil/internal.h"

  30. #include "libavutil/intreadwrite.h"

  31. #include "libavutil/mathematics.h"

  32. #include "avformat.h"

  33. #include "avi.h"

  34. #include "dv.h"

  35. #include "internal.h"

  36. #include "riff.h"

  37. 

  38. typedef struct AVIStream {

  39.     int64_t frame_offset;   /* current frame (video) or byte (audio) counter

  40.                              * (used to compute the pts) */

  41.     int remaining;

  42.     int packet_size;

  43. 

  44.     uint32_t scale;

  45.     uint32_t rate;

  46.     int sample_size;        /* size of one sample (or packet)

  47.                              * (in the rate/scale sense) in bytes */

  48. 

  49.     int64_t cum_len;        /* temporary storage (used during seek) */

  50.     int prefix;             /* normally 'd'<<8 + 'c' or 'w'<<8 + 'b' */

  51.     int prefix_count;

  52.     uint32_t pal[256];

  53.     int has_pal;

  54.     int dshow_block_align;  /* block align variable used to emulate bugs in

  55.                              * the MS dshow demuxer */

  56. 

  57.     AVFormatContext *sub_ctx;

  58.     AVPacket sub_pkt;

  59.     uint8_t *sub_buffer;

  60. 

  61.     int64_t seek_pos;

  62. } AVIStream;

  63. 

  64. typedef struct {

  65.     const AVClass *class;

  66.     int64_t riff_end;

  67.     int64_t movi_end;

  68.     int64_t fsize;

  69.     int64_t io_fsize;

  70.     int64_t movi_list;

  71.     int64_t last_pkt_pos;

  72.     int index_loaded;

  73.     int is_odml;

  74.     int non_interleaved;

  75.     int stream_index;

  76.     DVDemuxContext *dv_demux;

  77.     int odml_depth;

  78.     int use_odml;

  79. #define MAX_ODML_DEPTH 1000

  80.     int64_t dts_max;

  81. } AVIContext;

  82. 

  83. 

  84. static const AVOption options[] = {

  85.     { "use_odml", "use odml index", offsetof(AVIContext, use_odml), AV_OPT_TYPE_INT, {.i64 = 1}, -1, 1, AV_OPT_FLAG_DECODING_PARAM},

  86.     { NULL },

  87. };

  88. 

  89. static const AVClass demuxer_class = {

  90.     .class_name = "avi",

  91.     .item_name  = av_default_item_name,

  92.     .option     = options,

  93.     .version    = LIBAVUTIL_VERSION_INT,

  94.     .category   = AV_CLASS_CATEGORY_DEMUXER,

  95. };

  96. 

  97. 

  98. static const char avi_headers[][8] = {

  99.     { 'R', 'I', 'F', 'F', 'A', 'V', 'I', ' '  },

  100.     { 'R', 'I', 'F', 'F', 'A', 'V', 'I', 'X'  },

  101.     { 'R', 'I', 'F', 'F', 'A', 'V', 'I', 0x19 },

  102.     { 'O', 'N', '2', ' ', 'O', 'N', '2', 'f'  },

  103.     { 'R', 'I', 'F', 'F', 'A', 'M', 'V', ' '  },

  104.     { 0 }

  105. };

  106. 

  107. static const AVMetadataConv avi_metadata_conv[] = {

  108.     { "strn", "title" },

  109.     { 0 },

  110. };

  111. 

  112. static int avi_load_index(AVFormatContext *s);

  113. static int guess_ni_flag(AVFormatContext *s);

  114. 

  115. #define print_tag(str, tag, size)                        \

  116.     av_dlog(NULL, "pos:%"PRIX64" %s: tag=%c%c%c%c size=0x%x\n", \

  117.             avio_tell(pb), str, tag & 0xff,              \

  118.             (tag >> 8) & 0xff,                           \

  119.             (tag >> 16) & 0xff,                          \

  120.             (tag >> 24) & 0xff,                          \

  121.             size)

  122. 

  123. static inline int get_duration(AVIStream *ast, int len)

  124. {

  125.     if (ast->sample_size)

  126.         return len;

  127.     else if (ast->dshow_block_align)

  128.         return (len + ast->dshow_block_align - 1) / ast->dshow_block_align;

  129.     else

  130.         return 1;

  131. }

  132. 

  133. static int get_riff(AVFormatContext *s, AVIOContext *pb)

  134. {

  135.     AVIContext *avi = s->priv_data;

  136.     char header[8];

  137.     int i;

  138. 

  139.     /* check RIFF header */

  140.     avio_read(pb, header, 4);

  141.     avi->riff_end  = avio_rl32(pb); /* RIFF chunk size */

  142.     avi->riff_end += avio_tell(pb); /* RIFF chunk end */

  143.     avio_read(pb, header + 4, 4);

  144. 

  145.     for (i = 0; avi_headers[i][0]; i++)

  146.         if (!memcmp(header, avi_headers[i], 8))

  147.             break;

  148.     if (!avi_headers[i][0])

  149.         return AVERROR_INVALIDDATA;

  150. 

  151.     if (header[7] == 0x19)

  152.         av_log(s, AV_LOG_INFO,

  153.                "This file has been generated by a totally broken muxer.\n");

  154. 

  155.     return 0;

  156. }

  157. 

  158. static int read_braindead_odml_indx(AVFormatContext *s, int frame_num)

  159. {

  160.     AVIContext *avi     = s->priv_data;

  161.     AVIOContext *pb     = s->pb;

  162.     int longs_pre_entry = avio_rl16(pb);

  163.     int index_sub_type  = avio_r8(pb);

  164.     int index_type      = avio_r8(pb);

  165.     int entries_in_use  = avio_rl32(pb);

  166.     int chunk_id        = avio_rl32(pb);

  167.     int64_t base        = avio_rl64(pb);

  168.     int stream_id       = ((chunk_id      & 0xFF) - '0') * 10 +

  169.                           ((chunk_id >> 8 & 0xFF) - '0');

  170.     AVStream *st;

  171.     AVIStream *ast;

  172.     int i;

  173.     int64_t last_pos = -1;

  174.     int64_t filesize = avi->fsize;

  175. 

  176.     av_dlog(s,

  177.             "longs_pre_entry:%d index_type:%d entries_in_use:%d "

  178.             "chunk_id:%X base:%16"PRIX64"\n",

  179.             longs_pre_entry,

  180.             index_type,

  181.             entries_in_use,

  182.             chunk_id,

  183.             base);

  184. 

  185.     if (stream_id >= s->nb_streams || stream_id < 0)

  186.         return AVERROR_INVALIDDATA;

  187.     st  = s->streams[stream_id];

  188.     ast = st->priv_data;

  189. 

  190.     if (index_sub_type)

  191.         return AVERROR_INVALIDDATA;

  192. 

  193.     avio_rl32(pb);

  194. 

  195.     if (index_type && longs_pre_entry != 2)

  196.         return AVERROR_INVALIDDATA;

  197.     if (index_type > 1)

  198.         return AVERROR_INVALIDDATA;

  199. 

  200.     if (filesize > 0 && base >= filesize) {

  201.         av_log(s, AV_LOG_ERROR, "ODML index invalid\n");

  202.         if (base >> 32 == (base & 0xFFFFFFFF) &&

  203.             (base & 0xFFFFFFFF) < filesize    &&

  204.             filesize <= 0xFFFFFFFF)

  205.             base &= 0xFFFFFFFF;

  206.         else

  207.             return AVERROR_INVALIDDATA;

  208.     }

  209. 

  210.     for (i = 0; i < entries_in_use; i++) {

  211.         if (index_type) {

  212.             int64_t pos = avio_rl32(pb) + base - 8;

  213.             int len     = avio_rl32(pb);

  214.             int key     = len >= 0;

  215.             len &= 0x7FFFFFFF;

  216. 

  217. #ifdef DEBUG_SEEK

  218.             av_log(s, AV_LOG_ERROR, "pos:%"PRId64", len:%X\n", pos, len);

  219. #endif

  220.             if (url_feof(pb))

  221.                 return AVERROR_INVALIDDATA;

  222. 

  223.             if (last_pos == pos || pos == base - 8)

  224.                 avi->non_interleaved = 1;

  225.             if (last_pos != pos && (len || !ast->sample_size))

  226.                 av_add_index_entry(st, pos, ast->cum_len, len, 0,

  227.                                    key ? AVINDEX_KEYFRAME : 0);

  228. 

  229.             ast->cum_len += get_duration(ast, len);

  230.             last_pos      = pos;

  231.         } else {

  232.             int64_t offset, pos;

  233.             int duration;

  234.             offset = avio_rl64(pb);

  235.             avio_rl32(pb);       /* size */

  236.             duration = avio_rl32(pb);

  237. 

  238.             if (url_feof(pb))

  239.                 return AVERROR_INVALIDDATA;

  240. 

  241.             pos = avio_tell(pb);

  242. 

  243.             if (avi->odml_depth > MAX_ODML_DEPTH) {

  244.                 av_log(s, AV_LOG_ERROR, "Too deeply nested ODML indexes\n");

  245.                 return AVERROR_INVALIDDATA;

  246.             }

  247. 

  248.             if (avio_seek(pb, offset + 8, SEEK_SET) < 0)

  249.                 return -1;

  250.             avi->odml_depth++;

  251.             read_braindead_odml_indx(s, frame_num);

  252.             avi->odml_depth--;

  253.             frame_num += duration;

  254. 

  255.             if (avio_seek(pb, pos, SEEK_SET) < 0) {

  256.                 av_log(s, AV_LOG_ERROR, "Failed to restore position after reading index\n");

  257.                 return -1;

  258.             }

  259. 

  260.         }

  261.     }

  262.     avi->index_loaded = 2;

  263.     return 0;

  264. }

  265. 

  266. static void clean_index(AVFormatContext *s)

  267. {

  268.     int i;

  269.     int64_t j;

  270. 

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

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

  273.         AVIStream *ast = st->priv_data;

  274.         int n          = st->nb_index_entries;

  275.         int max        = ast->sample_size;

  276.         int64_t pos, size, ts;

  277. 

  278.         if (n != 1 || ast->sample_size == 0)

  279.             continue;

  280. 

  281.         while (max < 1024)

  282.             max += max;

  283. 

  284.         pos  = st->index_entries[0].pos;

  285.         size = st->index_entries[0].size;

  286.         ts   = st->index_entries[0].timestamp;

  287. 

  288.         for (j = 0; j < size; j += max)

  289.             av_add_index_entry(st, pos + j, ts + j, FFMIN(max, size - j), 0,

  290.                                AVINDEX_KEYFRAME);

  291.     }

  292. }

  293. 

  294. static int avi_read_tag(AVFormatContext *s, AVStream *st, uint32_t tag,

  295.                         uint32_t size)

  296. {

  297.     AVIOContext *pb = s->pb;

  298.     char key[5]     = { 0 };

  299.     char *value;

  300. 

  301.     size += (size & 1);

  302. 

  303.     if (size == UINT_MAX)

  304.         return AVERROR(EINVAL);

  305.     value = av_malloc(size + 1);

  306.     if (!value)

  307.         return AVERROR(ENOMEM);

  308.     avio_read(pb, value, size);

  309.     value[size] = 0;

  310. 

  311.     AV_WL32(key, tag);

  312. 

  313.     return av_dict_set(st ? &st->metadata : &s->metadata, key, value,

  314.                        AV_DICT_DONT_STRDUP_VAL);

  315. }

  316. 

  317. static const char months[12][4] = { "Jan", "Feb", "Mar", "Apr", "May", "Jun",

  318.                                     "Jul", "Aug", "Sep", "Oct", "Nov", "Dec" };

  319. 

  320. static void avi_metadata_creation_time(AVDictionary **metadata, char *date)

  321. {

  322.     char month[4], time[9], buffer[64];

  323.     int i, day, year;

  324.     /* parse standard AVI date format (ie. "Mon Mar 10 15:04:43 2003") */

  325.     if (sscanf(date, "%*3s%*[ ]%3s%*[ ]%2d%*[ ]%8s%*[ ]%4d",

  326.                month, &day, time, &year) == 4) {

  327.         for (i = 0; i < 12; i++)

  328.             if (!av_strcasecmp(month, months[i])) {

  329.                 snprintf(buffer, sizeof(buffer), "%.4d-%.2d-%.2d %s",

  330.                          year, i + 1, day, time);

  331.                 av_dict_set(metadata, "creation_time", buffer, 0);

  332.             }

  333.     } else if (date[4] == '/' && date[7] == '/') {

  334.         date[4] = date[7] = '-';

  335.         av_dict_set(metadata, "creation_time", date, 0);

  336.     }

  337. }

  338. 

  339. static void avi_read_nikon(AVFormatContext *s, uint64_t end)

  340. {

  341.     while (avio_tell(s->pb) < end) {

  342.         uint32_t tag  = avio_rl32(s->pb);

  343.         uint32_t size = avio_rl32(s->pb);

  344.         switch (tag) {

  345.         case MKTAG('n', 'c', 't', 'g'):  /* Nikon Tags */

  346.         {

  347.             uint64_t tag_end = avio_tell(s->pb) + size;

  348.             while (avio_tell(s->pb) < tag_end) {

  349.                 uint16_t tag     = avio_rl16(s->pb);

  350.                 uint16_t size    = avio_rl16(s->pb);

  351.                 const char *name = NULL;

  352.                 char buffer[64]  = { 0 };

  353.                 size = FFMIN(size, tag_end - avio_tell(s->pb));

  354.                 size -= avio_read(s->pb, buffer,

  355.                                   FFMIN(size, sizeof(buffer) - 1));

  356.                 switch (tag) {

  357.                 case 0x03:

  358.                     name = "maker";

  359.                     break;

  360.                 case 0x04:

  361.                     name = "model";

  362.                     break;

  363.                 case 0x13:

  364.                     name = "creation_time";

  365.                     if (buffer[4] == ':' && buffer[7] == ':')

  366.                         buffer[4] = buffer[7] = '-';

  367.                     break;

  368.                 }

  369.                 if (name)

  370.                     av_dict_set(&s->metadata, name, buffer, 0);

  371.                 avio_skip(s->pb, size);

  372.             }

  373.             break;

  374.         }

  375.         default:

  376.             avio_skip(s->pb, size);

  377.             break;

  378.         }

  379.     }

  380. }

  381. 

  382. static int avi_read_header(AVFormatContext *s)

  383. {

  384.     AVIContext *avi = s->priv_data;

  385.     AVIOContext *pb = s->pb;

  386.     unsigned int tag, tag1, handler;

  387.     int codec_type, stream_index, frame_period;

  388.     unsigned int size;

  389.     int i;

  390.     AVStream *st;

  391.     AVIStream *ast      = NULL;

  392.     int avih_width      = 0, avih_height = 0;

  393.     int amv_file_format = 0;

  394.     uint64_t list_end   = 0;

  395.     int ret;

  396.     AVDictionaryEntry *dict_entry;

  397. 

  398.     avi->stream_index = -1;

  399. 

  400.     ret = get_riff(s, pb);

  401.     if (ret < 0)

  402.         return ret;

  403. 

  404.     av_log(avi, AV_LOG_DEBUG, "use odml:%d\n", avi->use_odml);

  405. 

  406.     avi->io_fsize = avi->fsize = avio_size(pb);

  407.     if (avi->fsize <= 0 || avi->fsize < avi->riff_end)

  408.         avi->fsize = avi->riff_end == 8 ? INT64_MAX : avi->riff_end;

  409. 

  410.     /* first list tag */

  411.     stream_index = -1;

  412.     codec_type   = -1;

  413.     frame_period = 0;

  414.     for (;;) {

  415.         if (url_feof(pb))

  416.             goto fail;

  417.         tag  = avio_rl32(pb);

  418.         size = avio_rl32(pb);

  419. 

  420.         print_tag("tag", tag, size);

  421. 

  422.         switch (tag) {

  423.         case MKTAG('L', 'I', 'S', 'T'):

  424.             list_end = avio_tell(pb) + size;

  425.             /* Ignored, except at start of video packets. */

  426.             tag1 = avio_rl32(pb);

  427. 

  428.             print_tag("list", tag1, 0);

  429. 

  430.             if (tag1 == MKTAG('m', 'o', 'v', 'i')) {

  431.                 avi->movi_list = avio_tell(pb) - 4;

  432.                 if (size)

  433.                     avi->movi_end = avi->movi_list + size + (size & 1);

  434.                 else

  435.                     avi->movi_end = avi->fsize;

  436.                 av_dlog(NULL, "movi end=%"PRIx64"\n", avi->movi_end);

  437.                 goto end_of_header;

  438.             } else if (tag1 == MKTAG('I', 'N', 'F', 'O'))

  439.                 ff_read_riff_info(s, size - 4);

  440.             else if (tag1 == MKTAG('n', 'c', 'd', 't'))

  441.                 avi_read_nikon(s, list_end);

  442. 

  443.             break;

  444.         case MKTAG('I', 'D', 'I', 'T'):

  445.         {

  446.             unsigned char date[64] = { 0 };

  447.             size += (size & 1);

  448.             size -= avio_read(pb, date, FFMIN(size, sizeof(date) - 1));

  449.             avio_skip(pb, size);

  450.             avi_metadata_creation_time(&s->metadata, date);

  451.             break;

  452.         }

  453.         case MKTAG('d', 'm', 'l', 'h'):

  454.             avi->is_odml = 1;

  455.             avio_skip(pb, size + (size & 1));

  456.             break;

  457.         case MKTAG('a', 'm', 'v', 'h'):

  458.             amv_file_format = 1;

  459.         case MKTAG('a', 'v', 'i', 'h'):

  460.             /* AVI header */

  461.             /* using frame_period is bad idea */

  462.             frame_period = avio_rl32(pb);

  463.             avio_rl32(pb); /* max. bytes per second */

  464.             avio_rl32(pb);

  465.             avi->non_interleaved |= avio_rl32(pb) & AVIF_MUSTUSEINDEX;

  466. 

  467.             avio_skip(pb, 2 * 4);

  468.             avio_rl32(pb);

  469.             avio_rl32(pb);

  470.             avih_width  = avio_rl32(pb);

  471.             avih_height = avio_rl32(pb);

  472. 

  473.             avio_skip(pb, size - 10 * 4);

  474.             break;

  475.         case MKTAG('s', 't', 'r', 'h'):

  476.             /* stream header */

  477. 

  478.             tag1    = avio_rl32(pb);

  479.             handler = avio_rl32(pb); /* codec tag */

  480. 

  481.             if (tag1 == MKTAG('p', 'a', 'd', 's')) {

  482.                 avio_skip(pb, size - 8);

  483.                 break;

  484.             } else {

  485.                 stream_index++;

  486.                 st = avformat_new_stream(s, NULL);

  487.                 if (!st)

  488.                     goto fail;

  489. 

  490.                 st->id = stream_index;

  491.                 ast    = av_mallocz(sizeof(AVIStream));

  492.                 if (!ast)

  493.                     goto fail;

  494.                 st->priv_data = ast;

  495.             }

  496.             if (amv_file_format)

  497.                 tag1 = stream_index ? MKTAG('a', 'u', 'd', 's')

  498.                                     : MKTAG('v', 'i', 'd', 's');

  499. 

  500.             print_tag("strh", tag1, -1);

  501. 

  502.             if (tag1 == MKTAG('i', 'a', 'v', 's') ||

  503.                 tag1 == MKTAG('i', 'v', 'a', 's')) {

  504.                 int64_t dv_dur;

  505. 

  506.                 /* After some consideration -- I don't think we

  507.                  * have to support anything but DV in type1 AVIs. */

  508.                 if (s->nb_streams != 1)

  509.                     goto fail;

  510. 

  511.                 if (handler != MKTAG('d', 'v', 's', 'd') &&

  512.                     handler != MKTAG('d', 'v', 'h', 'd') &&

  513.                     handler != MKTAG('d', 'v', 's', 'l'))

  514.                     goto fail;

  515. 

  516.                 ast = s->streams[0]->priv_data;

  517.                 av_freep(&s->streams[0]->codec->extradata);

  518.                 av_freep(&s->streams[0]->codec);

  519.                 if (s->streams[0]->info)

  520.                     av_freep(&s->streams[0]->info->duration_error);

  521.                 av_freep(&s->streams[0]->info);

  522.                 av_freep(&s->streams[0]);

  523.                 s->nb_streams = 0;

  524.                 if (CONFIG_DV_DEMUXER) {

  525.                     avi->dv_demux = avpriv_dv_init_demux(s);

  526.                     if (!avi->dv_demux)

  527.                         goto fail;

  528.                 } else

  529.                     goto fail;

  530.                 s->streams[0]->priv_data = ast;

  531.                 avio_skip(pb, 3 * 4);

  532.                 ast->scale = avio_rl32(pb);

  533.                 ast->rate  = avio_rl32(pb);

  534.                 avio_skip(pb, 4);  /* start time */

  535. 

  536.                 dv_dur = avio_rl32(pb);

  537.                 if (ast->scale > 0 && ast->rate > 0 && dv_dur > 0) {

  538.                     dv_dur     *= AV_TIME_BASE;

  539.                     s->duration = av_rescale(dv_dur, ast->scale, ast->rate);

  540.                 }

  541.                 /* else, leave duration alone; timing estimation in utils.c

  542.                  * will make a guess based on bitrate. */

  543. 

  544.                 stream_index = s->nb_streams - 1;

  545.                 avio_skip(pb, size - 9 * 4);

  546.                 break;

  547.             }

  548. 

  549.             av_assert0(stream_index < s->nb_streams);

  550.             st->codec->stream_codec_tag = handler;

  551. 

  552.             avio_rl32(pb); /* flags */

  553.             avio_rl16(pb); /* priority */

  554.             avio_rl16(pb); /* language */

  555.             avio_rl32(pb); /* initial frame */

  556.             ast->scale = avio_rl32(pb);

  557.             ast->rate  = avio_rl32(pb);

  558.             if (!(ast->scale && ast->rate)) {

  559.                 av_log(s, AV_LOG_WARNING,

  560.                        "scale/rate is %u/%u which is invalid. "

  561.                        "(This file has been generated by broken software.)\n",

  562.                        ast->scale,

  563.                        ast->rate);

  564.                 if (frame_period) {

  565.                     ast->rate  = 1000000;

  566.                     ast->scale = frame_period;

  567.                 } else {

  568.                     ast->rate  = 25;

  569.                     ast->scale = 1;

  570.                 }

  571.             }

  572.             avpriv_set_pts_info(st, 64, ast->scale, ast->rate);

  573. 

  574.             ast->cum_len  = avio_rl32(pb); /* start */

  575.             st->nb_frames = avio_rl32(pb);

  576. 

  577.             st->start_time = 0;

  578.             avio_rl32(pb); /* buffer size */

  579.             avio_rl32(pb); /* quality */

  580.             if (ast->cum_len*ast->scale/ast->rate > 3600) {

  581.                 av_log(s, AV_LOG_ERROR, "crazy start time, iam scared, giving up\n");

  582.                 return AVERROR_INVALIDDATA;

  583.             }

  584.             ast->sample_size = avio_rl32(pb); /* sample ssize */

  585.             ast->cum_len    *= FFMAX(1, ast->sample_size);

  586.             av_dlog(s, "%"PRIu32" %"PRIu32" %d\n",

  587.                     ast->rate, ast->scale, ast->sample_size);

  588. 

  589.             switch (tag1) {

  590.             case MKTAG('v', 'i', 'd', 's'):

  591.                 codec_type = AVMEDIA_TYPE_VIDEO;

  592. 

  593.                 ast->sample_size = 0;

  594.                 break;

  595.             case MKTAG('a', 'u', 'd', 's'):

  596.                 codec_type = AVMEDIA_TYPE_AUDIO;

  597.                 break;

  598.             case MKTAG('t', 'x', 't', 's'):

  599.                 codec_type = AVMEDIA_TYPE_SUBTITLE;

  600.                 break;

  601.             case MKTAG('d', 'a', 't', 's'):

  602.                 codec_type = AVMEDIA_TYPE_DATA;

  603.                 break;

  604.             default:

  605.                 av_log(s, AV_LOG_INFO, "unknown stream type %X\n", tag1);

  606.             }

  607.             if (ast->sample_size == 0) {

  608.                 st->duration = st->nb_frames;

  609.                 if (st->duration > 0 && avi->io_fsize > 0 && avi->riff_end > avi->io_fsize) {

  610.                     av_log(s, AV_LOG_DEBUG, "File is truncated adjusting duration\n");

  611.                     st->duration = av_rescale(st->duration, avi->io_fsize, avi->riff_end);

  612.                 }

  613.             }

  614.             ast->frame_offset = ast->cum_len;

  615.             avio_skip(pb, size - 12 * 4);

  616.             break;

  617.         case MKTAG('s', 't', 'r', 'f'):

  618.             /* stream header */

  619.             if (!size)

  620.                 break;

  621.             if (stream_index >= (unsigned)s->nb_streams || avi->dv_demux) {

  622.                 avio_skip(pb, size);

  623.             } else {

  624.                 uint64_t cur_pos = avio_tell(pb);

  625.                 unsigned esize;

  626.                 if (cur_pos < list_end)

  627.                     size = FFMIN(size, list_end - cur_pos);

  628.                 st = s->streams[stream_index];

  629.                 if (st->codec->codec_type != AVMEDIA_TYPE_UNKNOWN) {

  630.                     avio_skip(pb, size);

  631.                     break;

  632.                 }

  633.                 switch (codec_type) {

  634.                 case AVMEDIA_TYPE_VIDEO:

  635.                     if (amv_file_format) {

  636.                         st->codec->width      = avih_width;

  637.                         st->codec->height     = avih_height;

  638.                         st->codec->codec_type = AVMEDIA_TYPE_VIDEO;

  639.                         st->codec->codec_id   = AV_CODEC_ID_AMV;

  640.                         avio_skip(pb, size);

  641.                         break;

  642.                     }

  643.                     tag1 = ff_get_bmp_header(pb, st, &esize);

  644. 

  645.                     if (tag1 == MKTAG('D', 'X', 'S', 'B') ||

  646.                         tag1 == MKTAG('D', 'X', 'S', 'A')) {

  647.                         st->codec->codec_type = AVMEDIA_TYPE_SUBTITLE;

  648.                         st->codec->codec_tag  = tag1;

  649.                         st->codec->codec_id   = AV_CODEC_ID_XSUB;

  650.                         break;

  651.                     }

  652. 

  653.                     if (size > 10 * 4 && size < (1 << 30) && size < avi->fsize) {

  654.                         if (esize == size-1 && (esize&1)) {

  655.                             st->codec->extradata_size = esize - 10 * 4;

  656.                         } else

  657.                             st->codec->extradata_size =  size - 10 * 4;

  658.                         if (ff_get_extradata(st->codec, pb, st->codec->extradata_size) < 0)

  659.                             return AVERROR(ENOMEM);

  660.                     }

  661. 

  662.                     // FIXME: check if the encoder really did this correctly

  663.                     if (st->codec->extradata_size & 1)

  664.                         avio_r8(pb);

  665. 

  666.                     /* Extract palette from extradata if bpp <= 8.

  667.                      * This code assumes that extradata contains only palette.

  668.                      * This is true for all paletted codecs implemented in

  669.                      * FFmpeg. */

  670.                     if (st->codec->extradata_size &&

  671.                         (st->codec->bits_per_coded_sample <= 8)) {

  672.                         int pal_size = (1 << st->codec->bits_per_coded_sample) << 2;

  673.                         const uint8_t *pal_src;

  674. 

  675.                         pal_size = FFMIN(pal_size, st->codec->extradata_size);

  676.                         pal_src  = st->codec->extradata +

  677.                                    st->codec->extradata_size - pal_size;

  678.                         for (i = 0; i < pal_size / 4; i++)

  679.                             ast->pal[i] = 0xFFU<<24 | AV_RL32(pal_src+4*i);

  680.                         ast->has_pal = 1;

  681.                     }

  682. 

  683.                     print_tag("video", tag1, 0);

  684. 

  685.                     st->codec->codec_type = AVMEDIA_TYPE_VIDEO;

  686.                     st->codec->codec_tag  = tag1;

  687.                     st->codec->codec_id   = ff_codec_get_id(ff_codec_bmp_tags,

  688.                                                             tag1);

  689.                     /* This is needed to get the pict type which is necessary

  690.                      * for generating correct pts. */

  691.                     st->need_parsing = AVSTREAM_PARSE_HEADERS;

  692.                     if (st->codec->codec_tag == MKTAG('V', 'S', 'S', 'H'))

  693.                         st->need_parsing = AVSTREAM_PARSE_FULL;

  694. 

  695.                     if (st->codec->codec_tag == 0 && st->codec->height > 0 &&

  696.                         st->codec->extradata_size < 1U << 30) {

  697.                         st->codec->extradata_size += 9;

  698.                         if ((ret = av_reallocp(&st->codec->extradata,

  699.                                                st->codec->extradata_size +

  700.                                                FF_INPUT_BUFFER_PADDING_SIZE)) < 0) {

  701.                             st->codec->extradata_size = 0;

  702.                             return ret;

  703.                         } else

  704.                             memcpy(st->codec->extradata + st->codec->extradata_size - 9,

  705.                                    "BottomUp", 9);

  706.                     }

  707.                     st->codec->height = FFABS(st->codec->height);

  708. 

  709. //                    avio_skip(pb, size - 5 * 4);

  710.                     break;

  711.                 case AVMEDIA_TYPE_AUDIO:

  712.                     ret = ff_get_wav_header(pb, st->codec, size);

  713.                     if (ret < 0)

  714.                         return ret;

  715.                     ast->dshow_block_align = st->codec->block_align;

  716.                     if (ast->sample_size && st->codec->block_align &&

  717.                         ast->sample_size != st->codec->block_align) {

  718.                         av_log(s,

  719.                                AV_LOG_WARNING,

  720.                                "sample size (%d) != block align (%d)\n",

  721.                                ast->sample_size,

  722.                                st->codec->block_align);

  723.                         ast->sample_size = st->codec->block_align;

  724.                     }

  725.                     /* 2-aligned

  726.                      * (fix for Stargate SG-1 - 3x18 - Shades of Grey.avi) */

  727.                     if (size & 1)

  728.                         avio_skip(pb, 1);

  729.                     /* Force parsing as several audio frames can be in

  730.                      * one packet and timestamps refer to packet start. */

  731.                     st->need_parsing = AVSTREAM_PARSE_TIMESTAMPS;

  732.                     /* ADTS header is in extradata, AAC without header must be

  733.                      * stored as exact frames. Parser not needed and it will

  734.                      * fail. */

  735.                     if (st->codec->codec_id == AV_CODEC_ID_AAC &&

  736.                         st->codec->extradata_size)

  737.                         st->need_parsing = AVSTREAM_PARSE_NONE;

  738.                     /* AVI files with Xan DPCM audio (wrongly) declare PCM

  739.                      * audio in the header but have Axan as stream_code_tag. */

  740.                     if (st->codec->stream_codec_tag == AV_RL32("Axan")) {

  741.                         st->codec->codec_id  = AV_CODEC_ID_XAN_DPCM;

  742.                         st->codec->codec_tag = 0;

  743.                         ast->dshow_block_align = 0;

  744.                     }

  745.                     if (amv_file_format) {

  746.                         st->codec->codec_id    = AV_CODEC_ID_ADPCM_IMA_AMV;

  747.                         ast->dshow_block_align = 0;

  748.                     }

  749.                     if (st->codec->codec_id == AV_CODEC_ID_AAC && ast->dshow_block_align <= 4 && ast->dshow_block_align) {

  750.                         av_log(s, AV_LOG_DEBUG, "overriding invalid dshow_block_align of %d\n", ast->dshow_block_align);

  751.                         ast->dshow_block_align = 0;

  752.                     }

  753.                     if (st->codec->codec_id == AV_CODEC_ID_AAC && ast->dshow_block_align == 1024 && ast->sample_size == 1024 ||

  754.                        st->codec->codec_id == AV_CODEC_ID_AAC && ast->dshow_block_align == 4096 && ast->sample_size == 4096 ||

  755.                        st->codec->codec_id == AV_CODEC_ID_MP3 && ast->dshow_block_align == 1152 && ast->sample_size == 1152) {

  756.                         av_log(s, AV_LOG_DEBUG, "overriding sample_size\n");

  757.                         ast->sample_size = 0;

  758.                     }

  759.                     break;

  760.                 case AVMEDIA_TYPE_SUBTITLE:

  761.                     st->codec->codec_type = AVMEDIA_TYPE_SUBTITLE;

  762.                     st->request_probe= 1;

  763.                     avio_skip(pb, size);

  764.                     break;

  765.                 default:

  766.                     st->codec->codec_type = AVMEDIA_TYPE_DATA;

  767.                     st->codec->codec_id   = AV_CODEC_ID_NONE;

  768.                     st->codec->codec_tag  = 0;

  769.                     avio_skip(pb, size);

  770.                     break;

  771.                 }

  772.             }

  773.             break;

  774.         case MKTAG('s', 't', 'r', 'd'):

  775.             if (stream_index >= (unsigned)s->nb_streams

  776.                 || s->streams[stream_index]->codec->extradata_size

  777.                 || s->streams[stream_index]->codec->codec_tag == MKTAG('H','2','6','4')) {

  778.                 avio_skip(pb, size);

  779.             } else {

  780.                 uint64_t cur_pos = avio_tell(pb);

  781.                 if (cur_pos < list_end)

  782.                     size = FFMIN(size, list_end - cur_pos);

  783.                 st = s->streams[stream_index];

  784. 

  785.                 if (size<(1<<30)) {

  786.                     if (ff_get_extradata(st->codec, pb, size) < 0)

  787.                         return AVERROR(ENOMEM);

  788.                 }

  789. 

  790.                 if (st->codec->extradata_size & 1) //FIXME check if the encoder really did this correctly

  791.                     avio_r8(pb);

  792.             }

  793.             break;

  794.         case MKTAG('i', 'n', 'd', 'x'):

  795.             i = avio_tell(pb);

  796.             if (pb->seekable && !(s->flags & AVFMT_FLAG_IGNIDX) &&

  797.                 avi->use_odml &&

  798.                 read_braindead_odml_indx(s, 0) < 0 &&

  799.                 (s->error_recognition & AV_EF_EXPLODE))

  800.                 goto fail;

  801.             avio_seek(pb, i + size, SEEK_SET);

  802.             break;

  803.         case MKTAG('v', 'p', 'r', 'p'):

  804.             if (stream_index < (unsigned)s->nb_streams && size > 9 * 4) {

  805.                 AVRational active, active_aspect;

  806. 

  807.                 st = s->streams[stream_index];

  808.                 avio_rl32(pb);

  809.                 avio_rl32(pb);

  810.                 avio_rl32(pb);

  811.                 avio_rl32(pb);

  812.                 avio_rl32(pb);

  813. 

  814.                 active_aspect.den = avio_rl16(pb);

  815.                 active_aspect.num = avio_rl16(pb);

  816.                 active.num        = avio_rl32(pb);

  817.                 active.den        = avio_rl32(pb);

  818.                 avio_rl32(pb); // nbFieldsPerFrame

  819. 

  820.                 if (active_aspect.num && active_aspect.den &&

  821.                     active.num && active.den) {

  822.                     st->sample_aspect_ratio = av_div_q(active_aspect, active);

  823.                     av_dlog(s, "vprp %d/%d %d/%d\n",

  824.                             active_aspect.num, active_aspect.den,

  825.                             active.num, active.den);

  826.                 }

  827.                 size -= 9 * 4;

  828.             }

  829.             avio_skip(pb, size);

  830.             break;

  831.         case MKTAG('s', 't', 'r', 'n'):

  832.             if (s->nb_streams) {

  833.                 ret = avi_read_tag(s, s->streams[s->nb_streams - 1], tag, size);

  834.                 if (ret < 0)

  835.                     return ret;

  836.                 break;

  837.             }

  838.         default:

  839.             if (size > 1000000) {

  840.                 av_log(s, AV_LOG_ERROR,

  841.                        "Something went wrong during header parsing, "

  842.                        "I will ignore it and try to continue anyway.\n");

  843.                 if (s->error_recognition & AV_EF_EXPLODE)

  844.                     goto fail;

  845.                 avi->movi_list = avio_tell(pb) - 4;

  846.                 avi->movi_end  = avi->fsize;

  847.                 goto end_of_header;

  848.             }

  849.             /* skip tag */

  850.             size += (size & 1);

  851.             avio_skip(pb, size);

  852.             break;

  853.         }

  854.     }

  855. 

  856. end_of_header:

  857.     /* check stream number */

  858.     if (stream_index != s->nb_streams - 1) {

  859. 

  860. fail:

  861.         return AVERROR_INVALIDDATA;

  862.     }

  863. 

  864.     if (!avi->index_loaded && pb->seekable)

  865.         avi_load_index(s);

  866.     avi->index_loaded    |= 1;

  867.     avi->non_interleaved |= guess_ni_flag(s) | (s->flags & AVFMT_FLAG_SORT_DTS);

  868. 

  869.     dict_entry = av_dict_get(s->metadata, "ISFT", NULL, 0);

  870.     if (dict_entry && !strcmp(dict_entry->value, "PotEncoder"))

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

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

  873.             if (   st->codec->codec_id == AV_CODEC_ID_MPEG1VIDEO

  874.                 || st->codec->codec_id == AV_CODEC_ID_MPEG2VIDEO)

  875.                 st->need_parsing = AVSTREAM_PARSE_FULL;

  876.         }

  877. 

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

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

  880.         if (st->nb_index_entries)

  881.             break;

  882.     }

  883.     // DV-in-AVI cannot be non-interleaved, if set this must be

  884.     // a mis-detection.

  885.     if (avi->dv_demux)

  886.         avi->non_interleaved = 0;

  887.     if (i == s->nb_streams && avi->non_interleaved) {

  888.         av_log(s, AV_LOG_WARNING,

  889.                "Non-interleaved AVI without index, switching to interleaved\n");

  890.         avi->non_interleaved = 0;

  891.     }

  892. 

  893.     if (avi->non_interleaved) {

  894.         av_log(s, AV_LOG_INFO, "non-interleaved AVI\n");

  895.         clean_index(s);

  896.     }

  897. 

  898.     ff_metadata_conv_ctx(s, NULL, avi_metadata_conv);

  899.     ff_metadata_conv_ctx(s, NULL, ff_riff_info_conv);

  900. 

  901.     return 0;

  902. }

  903. 

  904. static int read_gab2_sub(AVStream *st, AVPacket *pkt)

  905. {

  906.     if (pkt->size >= 7 &&

  907.         !strcmp(pkt->data, "GAB2") && AV_RL16(pkt->data + 5) == 2) {

  908.         uint8_t desc[256];

  909.         int score      = AVPROBE_SCORE_EXTENSION, ret;

  910.         AVIStream *ast = st->priv_data;

  911.         AVInputFormat *sub_demuxer;

  912.         AVRational time_base;

  913.         AVIOContext *pb = avio_alloc_context(pkt->data + 7,

  914.                                              pkt->size - 7,

  915.                                              0, NULL, NULL, NULL, NULL);

  916.         AVProbeData pd;

  917.         unsigned int desc_len = avio_rl32(pb);

  918. 

  919.         if (desc_len > pb->buf_end - pb->buf_ptr)

  920.             goto error;

  921. 

  922.         ret = avio_get_str16le(pb, desc_len, desc, sizeof(desc));

  923.         avio_skip(pb, desc_len - ret);

  924.         if (*desc)

  925.             av_dict_set(&st->metadata, "title", desc, 0);

  926. 

  927.         avio_rl16(pb);   /* flags? */

  928.         avio_rl32(pb);   /* data size */

  929. 

  930.         pd = (AVProbeData) { .buf      = pb->buf_ptr,

  931.                              .buf_size = pb->buf_end - pb->buf_ptr };

  932.         if (!(sub_demuxer = av_probe_input_format2(&pd, 1, &score)))

  933.             goto error;

  934. 

  935.         if (!(ast->sub_ctx = avformat_alloc_context()))

  936.             goto error;

  937. 

  938.         ast->sub_ctx->pb = pb;

  939.         if (!avformat_open_input(&ast->sub_ctx, "", sub_demuxer, NULL)) {

  940.             ff_read_packet(ast->sub_ctx, &ast->sub_pkt);

  941.             *st->codec = *ast->sub_ctx->streams[0]->codec;

  942.             ast->sub_ctx->streams[0]->codec->extradata = NULL;

  943.             time_base = ast->sub_ctx->streams[0]->time_base;

  944.             avpriv_set_pts_info(st, 64, time_base.num, time_base.den);

  945.         }

  946.         ast->sub_buffer = pkt->data;

  947.         memset(pkt, 0, sizeof(*pkt));

  948.         return 1;

  949. 

  950. error:

  951.         av_freep(&pb);

  952.     }

  953.     return 0;

  954. }

  955. 

  956. static AVStream *get_subtitle_pkt(AVFormatContext *s, AVStream *next_st,

  957.                                   AVPacket *pkt)

  958. {

  959.     AVIStream *ast, *next_ast = next_st->priv_data;

  960.     int64_t ts, next_ts, ts_min = INT64_MAX;

  961.     AVStream *st, *sub_st = NULL;

  962.     int i;

  963. 

  964.     next_ts = av_rescale_q(next_ast->frame_offset, next_st->time_base,

  965.                            AV_TIME_BASE_Q);

  966. 

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

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

  969.         ast = st->priv_data;

  970.         if (st->discard < AVDISCARD_ALL && ast && ast->sub_pkt.data) {

  971.             ts = av_rescale_q(ast->sub_pkt.dts, st->time_base, AV_TIME_BASE_Q);

  972.             if (ts <= next_ts && ts < ts_min) {

  973.                 ts_min = ts;

  974.                 sub_st = st;

  975.             }

  976.         }

  977.     }

  978. 

  979.     if (sub_st) {

  980.         ast               = sub_st->priv_data;

  981.         *pkt              = ast->sub_pkt;

  982.         pkt->stream_index = sub_st->index;

  983. 

  984.         if (ff_read_packet(ast->sub_ctx, &ast->sub_pkt) < 0)

  985.             ast->sub_pkt.data = NULL;

  986.     }

  987.     return sub_st;

  988. }

  989. 

  990. static int get_stream_idx(unsigned *d)

  991. {

  992.     if (d[0] >= '0' && d[0] <= '9' &&

  993.         d[1] >= '0' && d[1] <= '9') {

  994.         return (d[0] - '0') * 10 + (d[1] - '0');

  995.     } else {

  996.         return 100; // invalid stream ID

  997.     }

  998. }

  999. 

  1000. /**

  1001.  *

  1002.  * @param exit_early set to 1 to just gather packet position without making the changes needed to actually read & return the packet

  1003.  */

  1004. static int avi_sync(AVFormatContext *s, int exit_early)

  1005. {

  1006.     AVIContext *avi = s->priv_data;

  1007.     AVIOContext *pb = s->pb;

  1008.     int n;

  1009.     unsigned int d[8];

  1010.     unsigned int size;

  1011.     int64_t i, sync;

  1012. 

  1013. start_sync:

  1014.     memset(d, -1, sizeof(d));

  1015.     for (i = sync = avio_tell(pb); !url_feof(pb); i++) {

  1016.         int j;

  1017. 

  1018.         for (j = 0; j < 7; j++)

  1019.             d[j] = d[j + 1];

  1020.         d[7] = avio_r8(pb);

  1021. 

  1022.         size = d[4] + (d[5] << 8) + (d[6] << 16) + (d[7] << 24);

  1023. 

  1024.         n = get_stream_idx(d + 2);

  1025.         av_dlog(s, "%X %X %X %X %X %X %X %X %"PRId64" %u %d\n",

  1026.                 d[0], d[1], d[2], d[3], d[4], d[5], d[6], d[7], i, size, n);

  1027.         if (i*(avi->io_fsize>0) + (uint64_t)size > avi->fsize || d[0] > 127)

  1028.             continue;

  1029. 

  1030.         // parse ix##

  1031.         if ((d[0] == 'i' && d[1] == 'x' && n < s->nb_streams) ||

  1032.             // parse JUNK

  1033.             (d[0] == 'J' && d[1] == 'U' && d[2] == 'N' && d[3] == 'K') ||

  1034.             (d[0] == 'i' && d[1] == 'd' && d[2] == 'x' && d[3] == '1')) {

  1035.             avio_skip(pb, size);

  1036.             goto start_sync;

  1037.         }

  1038. 

  1039.         // parse stray LIST

  1040.         if (d[0] == 'L' && d[1] == 'I' && d[2] == 'S' && d[3] == 'T') {

  1041.             avio_skip(pb, 4);

  1042.             goto start_sync;

  1043.         }

  1044. 

  1045.         n = avi->dv_demux ? 0 : get_stream_idx(d);

  1046. 

  1047.         if (!((i - avi->last_pkt_pos) & 1) &&

  1048.             get_stream_idx(d + 1) < s->nb_streams)

  1049.             continue;

  1050. 

  1051.         // detect ##ix chunk and skip

  1052.         if (d[2] == 'i' && d[3] == 'x' && n < s->nb_streams) {

  1053.             avio_skip(pb, size);

  1054.             goto start_sync;

  1055.         }

  1056. 

  1057.         // parse ##dc/##wb

  1058.         if (n < s->nb_streams) {

  1059.             AVStream *st;

  1060.             AVIStream *ast;

  1061.             st  = s->streams[n];

  1062.             ast = st->priv_data;

  1063. 

  1064.             if (!ast) {

  1065.                 av_log(s, AV_LOG_WARNING, "Skiping foreign stream %d packet\n", n);

  1066.                 continue;

  1067.             }

  1068. 

  1069.             if (s->nb_streams >= 2) {

  1070.                 AVStream *st1   = s->streams[1];

  1071.                 AVIStream *ast1 = st1->priv_data;

  1072.                 // workaround for broken small-file-bug402.avi

  1073.                 if (   d[2] == 'w' && d[3] == 'b'

  1074.                    && n == 0

  1075.                    && st ->codec->codec_type == AVMEDIA_TYPE_VIDEO

  1076.                    && st1->codec->codec_type == AVMEDIA_TYPE_AUDIO

  1077.                    && ast->prefix == 'd'*256+'c'

  1078.                    && (d[2]*256+d[3] == ast1->prefix || !ast1->prefix_count)

  1079.                   ) {

  1080.                     n   = 1;

  1081.                     st  = st1;

  1082.                     ast = ast1;

  1083.                     av_log(s, AV_LOG_WARNING,

  1084.                            "Invalid stream + prefix combination, assuming audio.\n");

  1085.                 }

  1086.             }

  1087. 

  1088.             if (!avi->dv_demux &&

  1089.                 ((st->discard >= AVDISCARD_DEFAULT && size == 0) /* ||

  1090.                  // FIXME: needs a little reordering

  1091.                  (st->discard >= AVDISCARD_NONKEY &&

  1092.                  !(pkt->flags & AV_PKT_FLAG_KEY)) */

  1093.                 || st->discard >= AVDISCARD_ALL)) {

  1094.                 if (!exit_early) {

  1095.                     ast->frame_offset += get_duration(ast, size);

  1096.                     avio_skip(pb, size);

  1097.                     goto start_sync;

  1098.                 }

  1099.             }

  1100. 

  1101.             if (d[2] == 'p' && d[3] == 'c' && size <= 4 * 256 + 4) {

  1102.                 int k    = avio_r8(pb);

  1103.                 int last = (k + avio_r8(pb) - 1) & 0xFF;

  1104. 

  1105.                 avio_rl16(pb); // flags

  1106. 

  1107.                 // b + (g << 8) + (r << 16);

  1108.                 for (; k <= last; k++)

  1109.                     ast->pal[k] = 0xFFU<<24 | avio_rb32(pb)>>8;

  1110. 

  1111.                 ast->has_pal = 1;

  1112.                 goto start_sync;

  1113.             } else if (((ast->prefix_count < 5 || sync + 9 > i) &&

  1114.                         d[2] < 128 && d[3] < 128) ||

  1115.                        d[2] * 256 + d[3] == ast->prefix /* ||

  1116.                        (d[2] == 'd' && d[3] == 'c') ||

  1117.                        (d[2] == 'w' && d[3] == 'b') */) {

  1118.                 if (exit_early)

  1119.                     return 0;

  1120.                 if (d[2] * 256 + d[3] == ast->prefix)

  1121.                     ast->prefix_count++;

  1122.                 else {

  1123.                     ast->prefix       = d[2] * 256 + d[3];

  1124.                     ast->prefix_count = 0;

  1125.                 }

  1126. 

  1127.                 avi->stream_index = n;

  1128.                 ast->packet_size  = size + 8;

  1129.                 ast->remaining    = size;

  1130. 

  1131.                 if (size || !ast->sample_size) {

  1132.                     uint64_t pos = avio_tell(pb) - 8;

  1133.                     if (!st->index_entries || !st->nb_index_entries ||

  1134.                         st->index_entries[st->nb_index_entries - 1].pos < pos) {

  1135.                         av_add_index_entry(st, pos, ast->frame_offset, size,

  1136.                                            0, AVINDEX_KEYFRAME);

  1137.                     }

  1138.                 }

  1139.                 return 0;

  1140.             }

  1141.         }

  1142.     }

  1143. 

  1144.     if (pb->error)

  1145.         return pb->error;

  1146.     return AVERROR_EOF;

  1147. }

  1148. 

  1149. static int avi_read_packet(AVFormatContext *s, AVPacket *pkt)

  1150. {

  1151.     AVIContext *avi = s->priv_data;

  1152.     AVIOContext *pb = s->pb;

  1153.     int err;

  1154. #if FF_API_DESTRUCT_PACKET

  1155.     void *dstr;

  1156. #endif

  1157. 

  1158.     if (CONFIG_DV_DEMUXER && avi->dv_demux) {

  1159.         int size = avpriv_dv_get_packet(avi->dv_demux, pkt);

  1160.         if (size >= 0)

  1161.             return size;

  1162.         else

  1163.             goto resync;

  1164.     }

  1165. 

  1166.     if (avi->non_interleaved) {

  1167.         int best_stream_index = 0;

  1168.         AVStream *best_st     = NULL;

  1169.         AVIStream *best_ast;

  1170.         int64_t best_ts = INT64_MAX;

  1171.         int i;

  1172. 

  1173.         for (i = 0; i < s->nb_streams; i++) {

  1174.             AVStream *st   = s->streams[i];

  1175.             AVIStream *ast = st->priv_data;

  1176.             int64_t ts     = ast->frame_offset;

  1177.             int64_t last_ts;

  1178. 

  1179.             if (!st->nb_index_entries)

  1180.                 continue;

  1181. 

  1182.             last_ts = st->index_entries[st->nb_index_entries - 1].timestamp;

  1183.             if (!ast->remaining && ts > last_ts)

  1184.                 continue;

  1185. 

  1186.             ts = av_rescale_q(ts, st->time_base,

  1187.                               (AVRational) { FFMAX(1, ast->sample_size),

  1188.                                              AV_TIME_BASE });

  1189. 

  1190.             av_dlog(s, "%"PRId64" %d/%d %"PRId64"\n", ts,

  1191.                     st->time_base.num, st->time_base.den, ast->frame_offset);

  1192.             if (ts < best_ts) {

  1193.                 best_ts           = ts;

  1194.                 best_st           = st;

  1195.                 best_stream_index = i;

  1196.             }

  1197.         }

  1198.         if (!best_st)

  1199.             return AVERROR_EOF;

  1200. 

  1201.         best_ast = best_st->priv_data;

  1202.         best_ts  = best_ast->frame_offset;

  1203.         if (best_ast->remaining) {

  1204.             i = av_index_search_timestamp(best_st,

  1205.                                           best_ts,

  1206.                                           AVSEEK_FLAG_ANY |

  1207.                                           AVSEEK_FLAG_BACKWARD);

  1208.         } else {

  1209.             i = av_index_search_timestamp(best_st, best_ts, AVSEEK_FLAG_ANY);

  1210.             if (i >= 0)

  1211.                 best_ast->frame_offset = best_st->index_entries[i].timestamp;

  1212.         }

  1213. 

  1214.         if (i >= 0) {

  1215.             int64_t pos = best_st->index_entries[i].pos;

  1216.             pos += best_ast->packet_size - best_ast->remaining;

  1217.             if (avio_seek(s->pb, pos + 8, SEEK_SET) < 0)

  1218.               return AVERROR_EOF;

  1219. 

  1220.             av_assert0(best_ast->remaining <= best_ast->packet_size);

  1221. 

  1222.             avi->stream_index = best_stream_index;

  1223.             if (!best_ast->remaining)

  1224.                 best_ast->packet_size =

  1225.                 best_ast->remaining   = best_st->index_entries[i].size;

  1226.         }

  1227.         else

  1228.           return AVERROR_EOF;

  1229.     }

  1230. 

  1231. resync:

  1232.     if (avi->stream_index >= 0) {

  1233.         AVStream *st   = s->streams[avi->stream_index];

  1234.         AVIStream *ast = st->priv_data;

  1235.         int size, err;

  1236. 

  1237.         if (get_subtitle_pkt(s, st, pkt))

  1238.             return 0;

  1239. 

  1240.         // minorityreport.AVI block_align=1024 sample_size=1 IMA-ADPCM

  1241.         if (ast->sample_size <= 1)

  1242.             size = INT_MAX;

  1243.         else if (ast->sample_size < 32)

  1244.             // arbitrary multiplier to avoid tiny packets for raw PCM data

  1245.             size = 1024 * ast->sample_size;

  1246.         else

  1247.             size = ast->sample_size;

  1248. 

  1249.         if (size > ast->remaining)

  1250.             size = ast->remaining;

  1251.         avi->last_pkt_pos = avio_tell(pb);

  1252.         err               = av_get_packet(pb, pkt, size);

  1253.         if (err < 0)

  1254.             return err;

  1255.         size = err;

  1256. 

  1257.         if (ast->has_pal && pkt->size < (unsigned)INT_MAX / 2) {

  1258.             uint8_t *pal;

  1259.             pal = av_packet_new_side_data(pkt,

  1260.                                           AV_PKT_DATA_PALETTE,

  1261.                                           AVPALETTE_SIZE);

  1262.             if (!pal) {

  1263.                 av_log(s, AV_LOG_ERROR,

  1264.                        "Failed to allocate data for palette\n");

  1265.             } else {

  1266.                 memcpy(pal, ast->pal, AVPALETTE_SIZE);

  1267.                 ast->has_pal = 0;

  1268.             }

  1269.         }

  1270. 

  1271.         if (CONFIG_DV_DEMUXER && avi->dv_demux) {

  1272.             AVBufferRef *avbuf = pkt->buf;

  1273. #if FF_API_DESTRUCT_PACKET

  1274. FF_DISABLE_DEPRECATION_WARNINGS

  1275.             dstr = pkt->destruct;

  1276. FF_ENABLE_DEPRECATION_WARNINGS

  1277. #endif

  1278.             size = avpriv_dv_produce_packet(avi->dv_demux, pkt,

  1279.                                             pkt->data, pkt->size, pkt->pos);

  1280. #if FF_API_DESTRUCT_PACKET

  1281. FF_DISABLE_DEPRECATION_WARNINGS

  1282.             pkt->destruct = dstr;

  1283. FF_ENABLE_DEPRECATION_WARNINGS

  1284. #endif

  1285.             pkt->buf    = avbuf;

  1286.             pkt->flags |= AV_PKT_FLAG_KEY;

  1287.             if (size < 0)

  1288.                 av_free_packet(pkt);

  1289.         } else if (st->codec->codec_type == AVMEDIA_TYPE_SUBTITLE &&

  1290.                    !st->codec->codec_tag && read_gab2_sub(st, pkt)) {

  1291.             ast->frame_offset++;

  1292.             avi->stream_index = -1;

  1293.             ast->remaining    = 0;

  1294.             goto resync;

  1295.         } else {

  1296.             /* XXX: How to handle B-frames in AVI? */

  1297.             pkt->dts = ast->frame_offset;

  1298. //                pkt->dts += ast->start;

  1299.             if (ast->sample_size)

  1300.                 pkt->dts /= ast->sample_size;

  1301.             av_dlog(s,

  1302.                     "dts:%"PRId64" offset:%"PRId64" %d/%d smpl_siz:%d "

  1303.                     "base:%d st:%d size:%d\n",

  1304.                     pkt->dts,

  1305.                     ast->frame_offset,

  1306.                     ast->scale,

  1307.                     ast->rate,

  1308.                     ast->sample_size,

  1309.                     AV_TIME_BASE,

  1310.                     avi->stream_index,

  1311.                     size);

  1312.             pkt->stream_index = avi->stream_index;

  1313. 

  1314.             if (st->codec->codec_type == AVMEDIA_TYPE_VIDEO && st->index_entries) {

  1315.                 AVIndexEntry *e;

  1316.                 int index;

  1317. 

  1318.                 index = av_index_search_timestamp(st, ast->frame_offset, 0);

  1319.                 e     = &st->index_entries[index];

  1320. 

  1321.                 if (index >= 0 && e->timestamp == ast->frame_offset) {

  1322.                     if (index == st->nb_index_entries-1) {

  1323.                         int key=1;

  1324.                         int i;

  1325.                         uint32_t state=-1;

  1326.                         for (i=0; i<FFMIN(size,256); i++) {

  1327.                             if (st->codec->codec_id == AV_CODEC_ID_MPEG4) {

  1328.                                 if (state == 0x1B6) {

  1329.                                     key= !(pkt->data[i]&0xC0);

  1330.                                     break;

  1331.                                 }

  1332.                             }else

  1333.                                 break;

  1334.                             state= (state<<8) + pkt->data[i];

  1335.                         }

  1336.                         if (!key)

  1337.                             e->flags &= ~AVINDEX_KEYFRAME;

  1338.                     }

  1339.                     if (e->flags & AVINDEX_KEYFRAME)

  1340.                         pkt->flags |= AV_PKT_FLAG_KEY;

  1341.                 }

  1342.             } else {

  1343.                 pkt->flags |= AV_PKT_FLAG_KEY;

  1344.             }

  1345.             ast->frame_offset += get_duration(ast, pkt->size);

  1346.         }

  1347.         ast->remaining -= err;

  1348.         if (!ast->remaining) {

  1349.             avi->stream_index = -1;

  1350.             ast->packet_size  = 0;

  1351.         }

  1352. 

  1353.         if (!avi->non_interleaved && pkt->pos >= 0 && ast->seek_pos > pkt->pos) {

  1354.             av_free_packet(pkt);

  1355.             goto resync;

  1356.         }

  1357.         ast->seek_pos= 0;

  1358. 

  1359.         if (!avi->non_interleaved && st->nb_index_entries>1 && avi->index_loaded>1) {

  1360.             int64_t dts= av_rescale_q(pkt->dts, st->time_base, AV_TIME_BASE_Q);

  1361. 

  1362.             if (avi->dts_max - dts > 2*AV_TIME_BASE) {

  1363.                 avi->non_interleaved= 1;

  1364.                 av_log(s, AV_LOG_INFO, "Switching to NI mode, due to poor interleaving\n");

  1365.             }else if (avi->dts_max < dts)

  1366.                 avi->dts_max = dts;

  1367.         }

  1368. 

  1369.         return 0;

  1370.     }

  1371. 

  1372.     if ((err = avi_sync(s, 0)) < 0)

  1373.         return err;

  1374.     goto resync;

  1375. }

  1376. 

  1377. /* XXX: We make the implicit supposition that the positions are sorted

  1378.  * for each stream. */

  1379. static int avi_read_idx1(AVFormatContext *s, int size)

  1380. {

  1381.     AVIContext *avi = s->priv_data;

  1382.     AVIOContext *pb = s->pb;

  1383.     int nb_index_entries, i;

  1384.     AVStream *st;

  1385.     AVIStream *ast;

  1386.     unsigned int index, tag, flags, pos, len, first_packet = 1;

  1387.     unsigned last_pos = -1;

  1388.     unsigned last_idx = -1;

  1389.     int64_t idx1_pos, first_packet_pos = 0, data_offset = 0;

  1390.     int anykey = 0;

  1391. 

  1392.     nb_index_entries = size / 16;

  1393.     if (nb_index_entries <= 0)

  1394.         return AVERROR_INVALIDDATA;

  1395. 

  1396.     idx1_pos = avio_tell(pb);

  1397.     avio_seek(pb, avi->movi_list + 4, SEEK_SET);

  1398.     if (avi_sync(s, 1) == 0)

  1399.         first_packet_pos = avio_tell(pb) - 8;

  1400.     avi->stream_index = -1;

  1401.     avio_seek(pb, idx1_pos, SEEK_SET);

  1402. 

  1403.     if (s->nb_streams == 1 && s->streams[0]->codec->codec_tag == AV_RL32("MMES")) {

  1404.         first_packet_pos = 0;

  1405.         data_offset = avi->movi_list;

  1406.     }

  1407. 

  1408.     /* Read the entries and sort them in each stream component. */

  1409.     for (i = 0; i < nb_index_entries; i++) {

  1410.         if (url_feof(pb))

  1411.             return -1;

  1412. 

  1413.         tag   = avio_rl32(pb);

  1414.         flags = avio_rl32(pb);

  1415.         pos   = avio_rl32(pb);

  1416.         len   = avio_rl32(pb);

  1417.         av_dlog(s, "%d: tag=0x%x flags=0x%x pos=0x%x len=%d/",

  1418.                 i, tag, flags, pos, len);

  1419. 

  1420.         index  = ((tag      & 0xff) - '0') * 10;

  1421.         index +=  (tag >> 8 & 0xff) - '0';

  1422.         if (index >= s->nb_streams)

  1423.             continue;

  1424.         st  = s->streams[index];

  1425.         ast = st->priv_data;

  1426. 

  1427.         if (first_packet && first_packet_pos) {

  1428.             data_offset  = first_packet_pos - pos;

  1429.             first_packet = 0;

  1430.         }

  1431.         pos += data_offset;

  1432. 

  1433.         av_dlog(s, "%d cum_len=%"PRId64"\n", len, ast->cum_len);

  1434. 

  1435.         // even if we have only a single stream, we should

  1436.         // switch to non-interleaved to get correct timestamps

  1437.         if (last_pos == pos)

  1438.             avi->non_interleaved = 1;

  1439.         if (last_idx != pos && len) {

  1440.             av_add_index_entry(st, pos, ast->cum_len, len, 0,

  1441.                                (flags & AVIIF_INDEX) ? AVINDEX_KEYFRAME : 0);

  1442.             last_idx= pos;

  1443.         }

  1444.         ast->cum_len += get_duration(ast, len);

  1445.         last_pos      = pos;

  1446.         anykey       |= flags&AVIIF_INDEX;

  1447.     }

  1448.     if (!anykey) {

  1449.         for (index = 0; index < s->nb_streams; index++) {

  1450.             st = s->streams[index];

  1451.             if (st->nb_index_entries)

  1452.                 st->index_entries[0].flags |= AVINDEX_KEYFRAME;

  1453.         }

  1454.     }

  1455.     return 0;

  1456. }

  1457. 

  1458. static int guess_ni_flag(AVFormatContext *s)

  1459. {

  1460.     int i;

  1461.     int64_t last_start = 0;

  1462.     int64_t first_end  = INT64_MAX;

  1463.     int64_t oldpos     = avio_tell(s->pb);

  1464.     int *idx;

  1465.     int64_t min_pos, pos;

  1466. 

  1467.     for (i = 0; i < s->nb_streams; i++) {

  1468.         AVStream *st = s->streams[i];

  1469.         int n        = st->nb_index_entries;

  1470.         unsigned int size;

  1471. 

  1472.         if (n <= 0)

  1473.             continue;

  1474. 

  1475.         if (n >= 2) {

  1476.             int64_t pos = st->index_entries[0].pos;

  1477.             avio_seek(s->pb, pos + 4, SEEK_SET);

  1478.             size = avio_rl32(s->pb);

  1479.             if (pos + size > st->index_entries[1].pos)

  1480.                 last_start = INT64_MAX;

  1481.         }

  1482. 

  1483.         if (st->index_entries[0].pos > last_start)

  1484.             last_start = st->index_entries[0].pos;

  1485.         if (st->index_entries[n - 1].pos < first_end)

  1486.             first_end = st->index_entries[n - 1].pos;

  1487.     }

  1488.     avio_seek(s->pb, oldpos, SEEK_SET);

  1489.     if (last_start > first_end)

  1490.         return 1;

  1491.     idx= av_calloc(s->nb_streams, sizeof(*idx));

  1492.     if (!idx)

  1493.         return 0;

  1494.     for (min_pos=pos=0; min_pos!=INT64_MAX; pos= min_pos+1LU) {

  1495.         int64_t max_dts = INT64_MIN/2, min_dts= INT64_MAX/2;

  1496.         min_pos = INT64_MAX;

  1497. 

  1498.         for (i=0; i<s->nb_streams; i++) {

  1499.             AVStream *st = s->streams[i];

  1500.             AVIStream *ast = st->priv_data;

  1501.             int n= st->nb_index_entries;

  1502.             while (idx[i]<n && st->index_entries[idx[i]].pos < pos)

  1503.                 idx[i]++;

  1504.             if (idx[i] < n) {

  1505.                 min_dts = FFMIN(min_dts, av_rescale_q(st->index_entries[idx[i]].timestamp/FFMAX(ast->sample_size, 1), st->time_base, AV_TIME_BASE_Q));

  1506.                 min_pos = FFMIN(min_pos, st->index_entries[idx[i]].pos);

  1507.             }

  1508.             if (idx[i])

  1509.                 max_dts = FFMAX(max_dts, av_rescale_q(st->index_entries[idx[i]-1].timestamp/FFMAX(ast->sample_size, 1), st->time_base, AV_TIME_BASE_Q));

  1510.         }

  1511.         if (max_dts - min_dts > 2*AV_TIME_BASE) {

  1512.             av_free(idx);

  1513.             return 1;

  1514.         }

  1515.     }

  1516.     av_free(idx);

  1517.     return 0;

  1518. }

  1519. 

  1520. static int avi_load_index(AVFormatContext *s)

  1521. {

  1522.     AVIContext *avi = s->priv_data;

  1523.     AVIOContext *pb = s->pb;

  1524.     uint32_t tag, size;

  1525.     int64_t pos = avio_tell(pb);

  1526.     int64_t next;

  1527.     int ret     = -1;

  1528. 

  1529.     if (avio_seek(pb, avi->movi_end, SEEK_SET) < 0)

  1530.         goto the_end; // maybe truncated file

  1531.     av_dlog(s, "movi_end=0x%"PRIx64"\n", avi->movi_end);

  1532.     for (;;) {

  1533.         tag  = avio_rl32(pb);

  1534.         size = avio_rl32(pb);

  1535.         if (url_feof(pb))

  1536.             break;

  1537.         next = avio_tell(pb) + size + (size & 1);

  1538. 

  1539.         av_dlog(s, "tag=%c%c%c%c size=0x%x\n",

  1540.                  tag        & 0xff,

  1541.                 (tag >>  8) & 0xff,

  1542.                 (tag >> 16) & 0xff,

  1543.                 (tag >> 24) & 0xff,

  1544.                 size);

  1545. 

  1546.         if (tag == MKTAG('i', 'd', 'x', '1') &&

  1547.             avi_read_idx1(s, size) >= 0) {

  1548.             avi->index_loaded=2;

  1549.             ret = 0;

  1550.         }else if (tag == MKTAG('L', 'I', 'S', 'T')) {

  1551.             uint32_t tag1 = avio_rl32(pb);

  1552. 

  1553.             if (tag1 == MKTAG('I', 'N', 'F', 'O'))

  1554.                 ff_read_riff_info(s, size - 4);

  1555.         }else if (!ret)

  1556.             break;

  1557. 

  1558.         if (avio_seek(pb, next, SEEK_SET) < 0)

  1559.             break; // something is wrong here

  1560.     }

  1561. 

  1562. the_end:

  1563.     avio_seek(pb, pos, SEEK_SET);

  1564.     return ret;

  1565. }

  1566. 

  1567. static void seek_subtitle(AVStream *st, AVStream *st2, int64_t timestamp)

  1568. {

  1569.     AVIStream *ast2 = st2->priv_data;

  1570.     int64_t ts2     = av_rescale_q(timestamp, st->time_base, st2->time_base);

  1571.     av_free_packet(&ast2->sub_pkt);

  1572.     if (avformat_seek_file(ast2->sub_ctx, 0, INT64_MIN, ts2, ts2, 0) >= 0 ||

  1573.         avformat_seek_file(ast2->sub_ctx, 0, ts2, ts2, INT64_MAX, 0) >= 0)

  1574.         ff_read_packet(ast2->sub_ctx, &ast2->sub_pkt);

  1575. }

  1576. 

  1577. static int avi_read_seek(AVFormatContext *s, int stream_index,

  1578.                          int64_t timestamp, int flags)

  1579. {

  1580.     AVIContext *avi = s->priv_data;

  1581.     AVStream *st;

  1582.     int i, index;

  1583.     int64_t pos, pos_min;

  1584.     AVIStream *ast;

  1585. 

  1586.     /* Does not matter which stream is requested dv in avi has the

  1587.      * stream information in the first video stream.

  1588.      */

  1589.     if (avi->dv_demux)

  1590.         stream_index = 0;

  1591. 

  1592.     if (!avi->index_loaded) {

  1593.         /* we only load the index on demand */

  1594.         avi_load_index(s);

  1595.         avi->index_loaded |= 1;

  1596.     }

  1597.     av_assert0(stream_index >= 0);

  1598. 

  1599.     st    = s->streams[stream_index];

  1600.     ast   = st->priv_data;

  1601.     index = av_index_search_timestamp(st,

  1602.                                       timestamp * FFMAX(ast->sample_size, 1),

  1603.                                       flags);

  1604.     if (index < 0) {

  1605.         if (st->nb_index_entries > 0)

  1606.             av_log(s, AV_LOG_DEBUG, "Failed to find timestamp %"PRId64 " in index %"PRId64 " .. %"PRId64 "\n",

  1607.                    timestamp * FFMAX(ast->sample_size, 1),

  1608.                    st->index_entries[0].timestamp,

  1609.                    st->index_entries[st->nb_index_entries - 1].timestamp);

  1610.         return AVERROR_INVALIDDATA;

  1611.     }

  1612. 

  1613.     /* find the position */

  1614.     pos       = st->index_entries[index].pos;

  1615.     timestamp = st->index_entries[index].timestamp / FFMAX(ast->sample_size, 1);

  1616. 

  1617.     av_dlog(s, "XX %"PRId64" %d %"PRId64"\n",

  1618.             timestamp, index, st->index_entries[index].timestamp);

  1619. 

  1620.     if (CONFIG_DV_DEMUXER && avi->dv_demux) {

  1621.         /* One and only one real stream for DV in AVI, and it has video  */

  1622.         /* offsets. Calling with other stream indexes should have failed */

  1623.         /* the av_index_search_timestamp call above.                     */

  1624. 

  1625.         if (avio_seek(s->pb, pos, SEEK_SET) < 0)

  1626.             return -1;

  1627. 

  1628.         /* Feed the DV video stream version of the timestamp to the */

  1629.         /* DV demux so it can synthesize correct timestamps.        */

  1630.         ff_dv_offset_reset(avi->dv_demux, timestamp);

  1631. 

  1632.         avi->stream_index = -1;

  1633.         return 0;

  1634.     }

  1635. 

  1636.     pos_min = pos;

  1637.     for (i = 0; i < s->nb_streams; i++) {

  1638.         AVStream *st2   = s->streams[i];

  1639.         AVIStream *ast2 = st2->priv_data;

  1640. 

  1641.         ast2->packet_size =

  1642.         ast2->remaining   = 0;

  1643. 

  1644.         if (ast2->sub_ctx) {

  1645.             seek_subtitle(st, st2, timestamp);

  1646.             continue;

  1647.         }

  1648. 

  1649.         if (st2->nb_index_entries <= 0)

  1650.             continue;

  1651. 

  1652. //        av_assert1(st2->codec->block_align);

  1653.         av_assert0((int64_t)st2->time_base.num * ast2->rate ==

  1654.                    (int64_t)st2->time_base.den * ast2->scale);

  1655.         index = av_index_search_timestamp(st2,

  1656.                                           av_rescale_q(timestamp,

  1657.                                                        st->time_base,

  1658.                                                        st2->time_base) *

  1659.                                           FFMAX(ast2->sample_size, 1),

  1660.                                           flags |

  1661.                                           AVSEEK_FLAG_BACKWARD |

  1662.                                           (st2->codec->codec_type != AVMEDIA_TYPE_VIDEO ? AVSEEK_FLAG_ANY : 0));

  1663.         if (index < 0)

  1664.             index = 0;

  1665.         ast2->seek_pos = st2->index_entries[index].pos;

  1666.         pos_min = FFMIN(pos_min,ast2->seek_pos);

  1667.     }

  1668.     for (i = 0; i < s->nb_streams; i++) {

  1669.         AVStream *st2 = s->streams[i];

  1670.         AVIStream *ast2 = st2->priv_data;

  1671. 

  1672.         if (ast2->sub_ctx || st2->nb_index_entries <= 0)

  1673.             continue;

  1674. 

  1675.         index = av_index_search_timestamp(

  1676.                 st2,

  1677.                 av_rescale_q(timestamp, st->time_base, st2->time_base) * FFMAX(ast2->sample_size, 1),

  1678.                 flags | AVSEEK_FLAG_BACKWARD | (st2->codec->codec_type != AVMEDIA_TYPE_VIDEO ? AVSEEK_FLAG_ANY : 0));

  1679.         if (index < 0)

  1680.             index = 0;

  1681.         while (!avi->non_interleaved && index>0 && st2->index_entries[index-1].pos >= pos_min)

  1682.             index--;

  1683.         ast2->frame_offset = st2->index_entries[index].timestamp;

  1684.     }

  1685. 

  1686.     /* do the seek */

  1687.     if (avio_seek(s->pb, pos_min, SEEK_SET) < 0) {

  1688.         av_log(s, AV_LOG_ERROR, "Seek failed\n");

  1689.         return -1;

  1690.     }

  1691.     avi->stream_index = -1;

  1692.     avi->dts_max      = INT_MIN;

  1693.     return 0;

  1694. }

  1695. 

  1696. static int avi_read_close(AVFormatContext *s)

  1697. {

  1698.     int i;

  1699.     AVIContext *avi = s->priv_data;

  1700. 

  1701.     for (i = 0; i < s->nb_streams; i++) {

  1702.         AVStream *st   = s->streams[i];

  1703.         AVIStream *ast = st->priv_data;

  1704.         if (ast) {

  1705.             if (ast->sub_ctx) {

  1706.                 av_freep(&ast->sub_ctx->pb);

  1707.                 avformat_close_input(&ast->sub_ctx);

  1708.             }

  1709.             av_free(ast->sub_buffer);

  1710.             av_free_packet(&ast->sub_pkt);

  1711.         }

  1712.     }

  1713. 

  1714.     av_free(avi->dv_demux);

  1715. 

  1716.     return 0;

  1717. }

  1718. 

  1719. static int avi_probe(AVProbeData *p)

  1720. {

  1721.     int i;

  1722. 

  1723.     /* check file header */

  1724.     for (i = 0; avi_headers[i][0]; i++)

  1725.         if (!memcmp(p->buf,     avi_headers[i],     4) &&

  1726.             !memcmp(p->buf + 8, avi_headers[i] + 4, 4))

  1727.             return AVPROBE_SCORE_MAX;

  1728. 

  1729.     return 0;

  1730. }

  1731. 

  1732. AVInputFormat ff_avi_demuxer = {

  1733.     .name           = "avi",

  1734.     .long_name      = NULL_IF_CONFIG_SMALL("AVI (Audio Video Interleaved)"),

  1735.     .priv_data_size = sizeof(AVIContext),

  1736.     .read_probe     = avi_probe,

  1737.     .read_header    = avi_read_header,

  1738.     .read_packet    = avi_read_packet,

  1739.     .read_close     = avi_read_close,

  1740.     .read_seek      = avi_read_seek,

  1741.     .priv_class = &demuxer_class,

  1742. };