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.
41391 Commits
32 Branches
850MB
Tree: c86d8aed74
Branches Tags
${ item.name }
Create branch ${ searchTerm }
from 'c86d8aed74'
${ noResults }
FFmpeg/libavformat/avidec.c

1607 lines
54KB
Raw Blame History 

  1. /*

  2.  * AVI demuxer

  3.  * Copyright (c) 2001 Fabrice Bellard

  4.  *

  5.  * This file is part of Libav.

  6.  *

  7.  * Libav 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.  * Libav 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 Libav; if not, write to the Free Software

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

  20.  */

  21. 

  22. #include <inttypes.h>

  23. 

  24. #include "libavutil/avstring.h"

  25. #include "libavutil/bswap.h"

  26. #include "libavutil/dict.h"

  27. #include "libavutil/internal.h"

  28. #include "libavutil/intreadwrite.h"

  29. #include "libavutil/mathematics.h"

  30. #include "avformat.h"

  31. #include "avi.h"

  32. #include "dv.h"

  33. #include "internal.h"

  34. #include "riff.h"

  35. 

  36. #undef NDEBUG

  37. #include <assert.h>

  38. 

  39. typedef struct AVIStream {

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

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

  42.     int remaining;

  43.     int packet_size;

  44. 

  45.     uint32_t handler;

  46.     uint32_t scale;

  47.     uint32_t rate;

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

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

  50. 

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

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

  53.     int prefix_count;

  54.     uint32_t pal[256];

  55.     int has_pal;

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

  57.                              * the MS dshow demuxer */

  58. 

  59.     AVFormatContext *sub_ctx;

  60.     AVPacket sub_pkt;

  61.     uint8_t *sub_buffer;

  62. } AVIStream;

  63. 

  64. typedef struct AVIContext {

  65.     int64_t riff_end;

  66.     int64_t movi_end;

  67.     int64_t fsize;

  68.     int64_t movi_list;

  69.     int64_t last_pkt_pos;

  70.     int index_loaded;

  71.     int is_odml;

  72.     int non_interleaved;

  73.     int stream_index;

  74.     DVDemuxContext *dv_demux;

  75.     int odml_depth;

  76. #define MAX_ODML_DEPTH 1000

  77. } AVIContext;

  78. 

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

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

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

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

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

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

  85.     { 0 }

  86. };

  87. 

  88. static const AVMetadataConv avi_metadata_conv[] = {

  89.     { "strn", "title" },

  90.     { 0 },

  91. };

  92. 

  93. static int avi_load_index(AVFormatContext *s);

  94. static int guess_ni_flag(AVFormatContext *s);

  95. 

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

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

  98.             str, tag & 0xff,                             \

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

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

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

  102.             size)

  103. 

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

  105. {

  106.     if (ast->sample_size)

  107.         return len;

  108.     else if (ast->dshow_block_align)

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

  110.     else

  111.         return 1;

  112. }

  113. 

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

  115. {

  116.     AVIContext *avi = s->priv_data;

  117.     char header[8];

  118.     int i;

  119. 

  120.     /* check RIFF header */

  121.     avio_read(pb, header, 4);

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

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

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

  125. 

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

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

  128.             break;

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

  130.         return AVERROR_INVALIDDATA;

  131. 

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

  133.         av_log(s, AV_LOG_INFO,

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

  135. 

  136.     return 0;

  137. }

  138. 

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

  140. {

  141.     AVIContext *avi     = s->priv_data;

  142.     AVIOContext *pb     = s->pb;

  143.     int longs_pre_entry = avio_rl16(pb);

  144.     int index_sub_type  = avio_r8(pb);

  145.     int index_type      = avio_r8(pb);

  146.     int entries_in_use  = avio_rl32(pb);

  147.     int chunk_id        = avio_rl32(pb);

  148.     int64_t base        = avio_rl64(pb);

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

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

  151.     AVStream *st;

  152.     AVIStream *ast;

  153.     int i;

  154.     int64_t last_pos = -1;

  155.     int64_t filesize = avi->fsize;

  156. 

  157.     av_dlog(s,

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

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

  160.             longs_pre_entry,

  161.             index_type,

  162.             entries_in_use,

  163.             chunk_id,

  164.             base);

  165. 

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

  167.         return AVERROR_INVALIDDATA;

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

  169.     ast = st->priv_data;

  170. 

  171.     if (index_sub_type)

  172.         return AVERROR_INVALIDDATA;

  173. 

  174.     avio_rl32(pb);

  175. 

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

  177.         return AVERROR_INVALIDDATA;

  178.     if (index_type > 1)

  179.         return AVERROR_INVALIDDATA;

  180. 

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

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

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

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

  185.             filesize <= 0xFFFFFFFF)

  186.             base &= 0xFFFFFFFF;

  187.         else

  188.             return AVERROR_INVALIDDATA;

  189.     }

  190. 

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

  192.         if (index_type) {

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

  194.             int len     = avio_rl32(pb);

  195.             int key     = len >= 0;

  196.             len &= 0x7FFFFFFF;

  197. 

  198.             av_dlog(s, "pos:%"PRId64", len:%X\n", pos, len);

  199. 

  200.             if (pb->eof_reached)

  201.                 return AVERROR_INVALIDDATA;

  202. 

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

  204.                 avi->non_interleaved = 1;

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

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

  207.                                    key ? AVINDEX_KEYFRAME : 0);

  208. 

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

  210.             last_pos      = pos;

  211.         } else {

  212.             int64_t offset, pos;

  213.             int duration;

  214.             offset = avio_rl64(pb);

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

  216.             duration = avio_rl32(pb);

  217. 

  218.             if (pb->eof_reached)

  219.                 return AVERROR_INVALIDDATA;

  220. 

  221.             pos = avio_tell(pb);

  222. 

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

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

  225.                 return AVERROR_INVALIDDATA;

  226.             }

  227. 

  228.             avio_seek(pb, offset + 8, SEEK_SET);

  229.             avi->odml_depth++;

  230.             read_braindead_odml_indx(s, frame_num);

  231.             avi->odml_depth--;

  232.             frame_num += duration;

  233. 

  234.             avio_seek(pb, pos, SEEK_SET);

  235.         }

  236.     }

  237.     avi->index_loaded = 1;

  238.     return 0;

  239. }

  240. 

  241. static void clean_index(AVFormatContext *s)

  242. {

  243.     int i;

  244.     int64_t j;

  245. 

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

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

  248.         AVIStream *ast = st->priv_data;

  249.         int n          = st->nb_index_entries;

  250.         int max        = ast->sample_size;

  251.         int64_t pos, size, ts;

  252. 

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

  254.             continue;

  255. 

  256.         while (max < 1024)

  257.             max += max;

  258. 

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

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

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

  262. 

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

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

  265.                                AVINDEX_KEYFRAME);

  266.     }

  267. }

  268. 

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

  270.                         uint32_t size)

  271. {

  272.     AVIOContext *pb = s->pb;

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

  274.     char *value;

  275. 

  276.     size += (size & 1);

  277. 

  278.     if (size == UINT_MAX)

  279.         return AVERROR(EINVAL);

  280.     value = av_malloc(size + 1);

  281.     if (!value)

  282.         return AVERROR(ENOMEM);

  283.     avio_read(pb, value, size);

  284.     value[size] = 0;

  285. 

  286.     AV_WL32(key, tag);

  287. 

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

  289.                        AV_DICT_DONT_STRDUP_VAL);

  290. }

  291. 

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

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

  294. 

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

  296. {

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

  298.     int i, day, year;

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

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

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

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

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

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

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

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

  307.             }

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

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

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

  311.     }

  312. }

  313. 

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

  315. {

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

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

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

  319.         switch (tag) {

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

  321.         {

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

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

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

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

  326.                 const char *name = NULL;

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

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

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

  330.                 switch (tag) {

  331.                 case 0x03:

  332.                     name = "maker";

  333.                     break;

  334.                 case 0x04:

  335.                     name = "model";

  336.                     break;

  337.                 case 0x13:

  338.                     name = "creation_time";

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

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

  341.                     break;

  342.                 }

  343.                 if (name)

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

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

  346.             }

  347.             break;

  348.         }

  349.         default:

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

  351.             break;

  352.         }

  353.     }

  354. }

  355. 

  356. static int avi_read_header(AVFormatContext *s)

  357. {

  358.     AVIContext *avi = s->priv_data;

  359.     AVIOContext *pb = s->pb;

  360.     unsigned int tag, tag1, handler;

  361.     int codec_type, stream_index, frame_period;

  362.     unsigned int size;

  363.     int i;

  364.     AVStream *st;

  365.     AVIStream *ast      = NULL;

  366.     int avih_width      = 0, avih_height = 0;

  367.     int amv_file_format = 0;

  368.     uint64_t list_end   = 0;

  369.     int ret;

  370. 

  371.     avi->stream_index = -1;

  372. 

  373.     ret = get_riff(s, pb);

  374.     if (ret < 0)

  375.         return ret;

  376. 

  377.     avi->fsize = avio_size(pb);

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

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

  380. 

  381.     /* first list tag */

  382.     stream_index = -1;

  383.     codec_type   = -1;

  384.     frame_period = 0;

  385.     for (;;) {

  386.         if (pb->eof_reached)

  387.             goto fail;

  388.         tag  = avio_rl32(pb);

  389.         size = avio_rl32(pb);

  390. 

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

  392. 

  393.         switch (tag) {

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

  395.             list_end = avio_tell(pb) + size;

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

  397.             tag1 = avio_rl32(pb);

  398. 

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

  400. 

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

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

  403.                 if (size)

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

  405.                 else

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

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

  408.                 goto end_of_header;

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

  410.                 ff_read_riff_info(s, size - 4);

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

  412.                 avi_read_nikon(s, list_end);

  413. 

  414.             break;

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

  416.         {

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

  418.             size += (size & 1);

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

  420.             avio_skip(pb, size);

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

  422.             break;

  423.         }

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

  425.             avi->is_odml = 1;

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

  427.             break;

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

  429.             amv_file_format = 1;

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

  431.             /* AVI header */

  432.             /* using frame_period is bad idea */

  433.             frame_period = avio_rl32(pb);

  434.             avio_skip(pb, 4);

  435.             avio_rl32(pb);

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

  437. 

  438.             avio_skip(pb, 2 * 4);

  439.             avio_rl32(pb);

  440.             avio_rl32(pb);

  441.             avih_width  = avio_rl32(pb);

  442.             avih_height = avio_rl32(pb);

  443. 

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

  445.             break;

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

  447.             /* stream header */

  448. 

  449.             tag1    = avio_rl32(pb);

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

  451. 

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

  453.                 avio_skip(pb, size - 8);

  454.                 break;

  455.             } else {

  456.                 stream_index++;

  457.                 st = avformat_new_stream(s, NULL);

  458.                 if (!st)

  459.                     goto fail;

  460. 

  461.                 st->id = stream_index;

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

  463.                 if (!ast)

  464.                     goto fail;

  465.                 st->priv_data = ast;

  466.             }

  467.             if (amv_file_format)

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

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

  470. 

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

  472. 

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

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

  475.                 int64_t dv_dur;

  476. 

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

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

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

  480.                     goto fail;

  481. 

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

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

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

  485.                     goto fail;

  486. 

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

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

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

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

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

  492.                 s->nb_streams = 0;

  493.                 if (CONFIG_DV_DEMUXER) {

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

  495.                     if (!avi->dv_demux)

  496.                         goto fail;

  497.                 } else

  498.                     goto fail;

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

  500.                 avio_skip(pb, 3 * 4);

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

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

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

  504. 

  505.                 dv_dur = avio_rl32(pb);

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

  507.                     dv_dur     *= AV_TIME_BASE;

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

  509.                 }

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

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

  512. 

  513.                 stream_index = s->nb_streams - 1;

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

  515.                 break;

  516.             }

  517. 

  518.             assert(stream_index < s->nb_streams);

  519.             ast->handler = handler;

  520. 

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

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

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

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

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

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

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

  528.                 av_log(s, AV_LOG_WARNING,

  529.                        "scale/rate is %"PRIu32"/%"PRIu32" which is invalid. "

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

  531.                        ast->scale,

  532.                        ast->rate);

  533.                 if (frame_period) {

  534.                     ast->rate  = 1000000;

  535.                     ast->scale = frame_period;

  536.                 } else {

  537.                     ast->rate  = 25;

  538.                     ast->scale = 1;

  539.                 }

  540.             }

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

  542. 

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

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

  545. 

  546.             st->start_time = 0;

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

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

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

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

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

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

  553. 

  554.             switch (tag1) {

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

  556.                 codec_type = AVMEDIA_TYPE_VIDEO;

  557. 

  558.                 ast->sample_size = 0;

  559.                 break;

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

  561.                 codec_type = AVMEDIA_TYPE_AUDIO;

  562.                 break;

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

  564.                 codec_type = AVMEDIA_TYPE_SUBTITLE;

  565.                 break;

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

  567.                 codec_type = AVMEDIA_TYPE_DATA;

  568.                 break;

  569.             default:

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

  571.                 goto fail;

  572.             }

  573.             if (ast->sample_size == 0)

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

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

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

  577.             break;

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

  579.             /* stream header */

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

  581.                 avio_skip(pb, size);

  582.             } else {

  583.                 uint64_t cur_pos = avio_tell(pb);

  584.                 if (cur_pos < list_end)

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

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

  587.                 switch (codec_type) {

  588.                 case AVMEDIA_TYPE_VIDEO:

  589.                     if (amv_file_format) {

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

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

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

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

  594.                         avio_skip(pb, size);

  595.                         break;

  596.                     }

  597.                     tag1 = ff_get_bmp_header(pb, st);

  598. 

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

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

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

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

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

  604.                         break;

  605.                     }

  606. 

  607.                     if (size > 10 * 4 && size < (1 << 30)) {

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

  609.                         st->codec->extradata      = av_malloc(st->codec->extradata_size +

  610.                                                               FF_INPUT_BUFFER_PADDING_SIZE);

  611.                         if (!st->codec->extradata) {

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

  613.                             return AVERROR(ENOMEM);

  614.                         }

  615.                         avio_read(pb,

  616.                                   st->codec->extradata,

  617.                                   st->codec->extradata_size);

  618.                     }

  619. 

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

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

  622.                         avio_r8(pb);

  623. 

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

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

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

  627.                      * Libav. */

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

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

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

  631.                         const uint8_t *pal_src;

  632. 

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

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

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

  636. #if HAVE_BIGENDIAN

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

  638.                             ast->pal[i] = av_bswap32(((uint32_t *)pal_src)[i]);

  639. #else

  640.                         memcpy(ast->pal, pal_src, pal_size);

  641. #endif

  642.                         ast->has_pal = 1;

  643.                     }

  644. 

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

  646. 

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

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

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

  650.                                                             tag1);

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

  652.                      * for generating correct pts. */

  653.                     st->need_parsing = AVSTREAM_PARSE_HEADERS;

  654. 

  655.                     if (st->codec->codec_id == AV_CODEC_ID_MPEG4 &&

  656.                         ast->handler == MKTAG('X', 'V', 'I', 'D'))

  657.                         st->codec->codec_tag = MKTAG('X', 'V', 'I', 'D');

  658. 

  659.                     // Support "Resolution 1:1" for Avid AVI Codec

  660.                     if (tag1 == MKTAG('A', 'V', 'R', 'n') &&

  661.                         st->codec->extradata_size >= 31   &&

  662.                         !memcmp(&st->codec->extradata[28], "1:1", 3))

  663.                         st->codec->codec_id = AV_CODEC_ID_RAWVIDEO;

  664. 

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

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

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

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

  669.                                                st->codec->extradata_size +

  670.                                                FF_INPUT_BUFFER_PADDING_SIZE)) < 0) {

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

  672.                             return ret;

  673.                         } else

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

  675.                                    "BottomUp", 9);

  676.                     }

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

  678. 

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

  680.                     break;

  681.                 case AVMEDIA_TYPE_AUDIO:

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

  683.                     if (ret < 0)

  684.                         return ret;

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

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

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

  688.                         av_log(s,

  689.                                AV_LOG_WARNING,

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

  691.                                ast->sample_size,

  692.                                st->codec->block_align);

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

  694.                     }

  695.                     /* 2-aligned

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

  697.                     if (size & 1)

  698.                         avio_skip(pb, 1);

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

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

  701.                     st->need_parsing = AVSTREAM_PARSE_TIMESTAMPS;

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

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

  704.                      * fail. */

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

  706.                         st->codec->extradata_size)

  707.                         st->need_parsing = AVSTREAM_PARSE_NONE;

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

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

  710.                     if (ast->handler == AV_RL32("Axan")) {

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

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

  713.                     }

  714.                     if (amv_file_format) {

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

  716.                         ast->dshow_block_align = 0;

  717.                     }

  718.                     break;

  719.                 case AVMEDIA_TYPE_SUBTITLE:

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

  721.                     st->codec->codec_id   = AV_CODEC_ID_PROBE;

  722.                     break;

  723.                 default:

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

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

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

  727.                     avio_skip(pb, size);

  728.                     break;

  729.                 }

  730.             }

  731.             break;

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

  733.             i = avio_tell(pb);

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

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

  736.                 (s->error_recognition & AV_EF_EXPLODE))

  737.                 goto fail;

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

  739.             break;

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

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

  742.                 AVRational active, active_aspect;

  743. 

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

  745.                 avio_rl32(pb);

  746.                 avio_rl32(pb);

  747.                 avio_rl32(pb);

  748.                 avio_rl32(pb);

  749.                 avio_rl32(pb);

  750. 

  751.                 active_aspect.den = avio_rl16(pb);

  752.                 active_aspect.num = avio_rl16(pb);

  753.                 active.num        = avio_rl32(pb);

  754.                 active.den        = avio_rl32(pb);

  755.                 avio_rl32(pb); // nbFieldsPerFrame

  756. 

  757.                 if (active_aspect.num && active_aspect.den &&

  758.                     active.num && active.den) {

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

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

  761.                             active_aspect.num, active_aspect.den,

  762.                             active.num, active.den);

  763.                 }

  764.                 size -= 9 * 4;

  765.             }

  766.             avio_skip(pb, size);

  767.             break;

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

  769.             if (s->nb_streams) {

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

  771.                 if (ret < 0)

  772.                     return ret;

  773.                 break;

  774.             }

  775.         default:

  776.             if (size > 1000000) {

  777.                 av_log(s, AV_LOG_ERROR,

  778.                        "Something went wrong during header parsing, "

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

  780.                 if (s->error_recognition & AV_EF_EXPLODE)

  781.                     goto fail;

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

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

  784.                 goto end_of_header;

  785.             }

  786.             /* skip tag */

  787.             size += (size & 1);

  788.             avio_skip(pb, size);

  789.             break;

  790.         }

  791.     }

  792. 

  793. end_of_header:

  794.     /* check stream number */

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

  796. 

  797. fail:

  798.         return AVERROR_INVALIDDATA;

  799.     }

  800. 

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

  802.         avi_load_index(s);

  803.     avi->index_loaded     = 1;

  804. 

  805.     if ((ret = guess_ni_flag(s)) < 0)

  806.         return ret;

  807. 

  808.     avi->non_interleaved |= ret;

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

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

  811.         if (st->nb_index_entries)

  812.             break;

  813.     }

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

  815.         av_log(s, AV_LOG_WARNING,

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

  817.         avi->non_interleaved = 0;

  818.     }

  819. 

  820.     if (avi->non_interleaved) {

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

  822.         clean_index(s);

  823.     }

  824. 

  825.     ff_metadata_conv_ctx(s, NULL, avi_metadata_conv);

  826.     ff_metadata_conv_ctx(s, NULL, ff_riff_info_conv);

  827. 

  828.     return 0;

  829. }

  830. 

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

  832. {

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

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

  835.         uint8_t desc[256];

  836.         int score      = AVPROBE_SCORE_EXTENSION, ret;

  837.         AVIStream *ast = st->priv_data;

  838.         AVInputFormat *sub_demuxer;

  839.         AVRational time_base;

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

  841.                                              pkt->size - 7,

  842.                                              0, NULL, NULL, NULL, NULL);

  843.         AVProbeData pd;

  844.         unsigned int desc_len = avio_rl32(pb);

  845. 

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

  847.             goto error;

  848. 

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

  850.         avio_skip(pb, desc_len - ret);

  851.         if (*desc)

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

  853. 

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

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

  856. 

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

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

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

  860.             goto error;

  861. 

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

  863.             goto error;

  864. 

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

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

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

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

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

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

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

  872.         }

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

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

  875.         return 1;

  876. 

  877. error:

  878.         av_freep(&pb);

  879.     }

  880.     return 0;

  881. }

  882. 

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

  884.                                   AVPacket *pkt)

  885. {

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

  887.     int64_t ts, next_ts, ts_min = INT64_MAX;

  888.     AVStream *st, *sub_st = NULL;

  889.     int i;

  890. 

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

  892.                            AV_TIME_BASE_Q);

  893. 

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

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

  896.         ast = st->priv_data;

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

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

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

  900.                 ts_min = ts;

  901.                 sub_st = st;

  902.             }

  903.         }

  904.     }

  905. 

  906.     if (sub_st) {

  907.         ast               = sub_st->priv_data;

  908.         *pkt              = ast->sub_pkt;

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

  910. 

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

  912.             ast->sub_pkt.data = NULL;

  913.     }

  914.     return sub_st;

  915. }

  916. 

  917. static int get_stream_idx(int *d)

  918. {

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

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

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

  922.     } else {

  923.         return 100; // invalid stream ID

  924.     }

  925. }

  926. 

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

  928. {

  929.     AVIContext *avi = s->priv_data;

  930.     AVIOContext *pb = s->pb;

  931.     int n;

  932.     unsigned int d[8];

  933.     unsigned int size;

  934.     int64_t i, sync;

  935. 

  936. start_sync:

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

  938.     for (i = sync = avio_tell(pb); !pb->eof_reached; i++) {

  939.         int j;

  940. 

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

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

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

  944. 

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

  946. 

  947.         n = get_stream_idx(d + 2);

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

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

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

  951.             continue;

  952. 

  953.         // parse ix##

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

  955.             // parse JUNK

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

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

  958.             avio_skip(pb, size);

  959.             goto start_sync;

  960.         }

  961. 

  962.         // parse stray LIST

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

  964.             avio_skip(pb, 4);

  965.             goto start_sync;

  966.         }

  967. 

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

  969. 

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

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

  972.             continue;

  973. 

  974.         // detect ##ix chunk and skip

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

  976.             avio_skip(pb, size);

  977.             goto start_sync;

  978.         }

  979. 

  980.         // parse ##dc/##wb

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

  982.             AVStream *st;

  983.             AVIStream *ast;

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

  985.             ast = st->priv_data;

  986. 

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

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

  989.                 AVIStream *ast1 = st1->priv_data;

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

  991.                 if (d[2] == 'w' && d[3] == 'b' && n == 0 &&

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

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

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

  995.                     (d[2] * 256 + d[3] == ast1->prefix ||

  996.                      !ast1->prefix_count)) {

  997.                     n   = 1;

  998.                     st  = st1;

  999.                     ast = ast1;

  1000.                     av_log(s, AV_LOG_WARNING,

  1001.                            "Invalid stream + prefix combination, assuming audio.\n");

  1002.                 }

  1003.             }

  1004. 

  1005.             if (!avi->dv_demux &&

  1006.                 ((st->discard >= AVDISCARD_DEFAULT && size == 0) /* ||

  1007.                  // FIXME: needs a little reordering

  1008.                  (st->discard >= AVDISCARD_NONKEY &&

  1009.                  !(pkt->flags & AV_PKT_FLAG_KEY)) */

  1010.                 || st->discard >= AVDISCARD_ALL)) {

  1011.                 if (!exit_early) {

  1012.                     ast->frame_offset += get_duration(ast, size);

  1013.                 }

  1014.                 avio_skip(pb, size);

  1015.                 goto start_sync;

  1016.             }

  1017. 

  1018.             if (d[2] == 'p' && d[3] == 'c' && size <= 4 * 256 + 4) {

  1019.                 int k    = avio_r8(pb);

  1020.                 int last = (k + avio_r8(pb) - 1) & 0xFF;

  1021. 

  1022.                 avio_rl16(pb); // flags

  1023. 

  1024.                 // b + (g << 8) + (r << 16);

  1025.                 for (; k <= last; k++)

  1026.                     ast->pal[k] = avio_rb32(pb) >> 8;

  1027. 

  1028.                 ast->has_pal = 1;

  1029.                 goto start_sync;

  1030.             } else if (((ast->prefix_count < 5 || sync + 9 > i) &&

  1031.                         d[2] < 128 && d[3] < 128) ||

  1032.                        d[2] * 256 + d[3] == ast->prefix /* ||

  1033.                        (d[2] == 'd' && d[3] == 'c') ||

  1034.                        (d[2] == 'w' && d[3] == 'b') */) {

  1035.                 if (exit_early)

  1036.                     return 0;

  1037.                 if (d[2] * 256 + d[3] == ast->prefix)

  1038.                     ast->prefix_count++;

  1039.                 else {

  1040.                     ast->prefix       = d[2] * 256 + d[3];

  1041.                     ast->prefix_count = 0;

  1042.                 }

  1043. 

  1044.                 avi->stream_index = n;

  1045.                 ast->packet_size  = size + 8;

  1046.                 ast->remaining    = size;

  1047. 

  1048.                 if (size || !ast->sample_size) {

  1049.                     uint64_t pos = avio_tell(pb) - 8;

  1050.                     if (!st->index_entries || !st->nb_index_entries ||

  1051.                         st->index_entries[st->nb_index_entries - 1].pos < pos) {

  1052.                         av_add_index_entry(st, pos, ast->frame_offset, size,

  1053.                                            0, AVINDEX_KEYFRAME);

  1054.                     }

  1055.                 }

  1056.                 return 0;

  1057.             }

  1058.         }

  1059.     }

  1060. 

  1061.     return AVERROR_EOF;

  1062. }

  1063. 

  1064. static int avi_read_packet(AVFormatContext *s, AVPacket *pkt)

  1065. {

  1066.     AVIContext *avi = s->priv_data;

  1067.     AVIOContext *pb = s->pb;

  1068.     int err;

  1069. #if FF_API_DESTRUCT_PACKET

  1070.     void *dstr;

  1071. #endif

  1072. 

  1073.     if (CONFIG_DV_DEMUXER && avi->dv_demux) {

  1074.         int size = avpriv_dv_get_packet(avi->dv_demux, pkt);

  1075.         if (size >= 0)

  1076.             return size;

  1077.         else

  1078.             goto resync;

  1079.     }

  1080. 

  1081.     if (avi->non_interleaved) {

  1082.         int best_stream_index = 0;

  1083.         AVStream *best_st     = NULL;

  1084.         AVIStream *best_ast;

  1085.         int64_t best_ts = INT64_MAX;

  1086.         int i;

  1087. 

  1088.         for (i = 0; i < s->nb_streams; i++) {

  1089.             AVStream *st   = s->streams[i];

  1090.             AVIStream *ast = st->priv_data;

  1091.             int64_t ts     = ast->frame_offset;

  1092.             int64_t last_ts;

  1093. 

  1094.             if (!st->nb_index_entries)

  1095.                 continue;

  1096. 

  1097.             last_ts = st->index_entries[st->nb_index_entries - 1].timestamp;

  1098.             if (!ast->remaining && ts > last_ts)

  1099.                 continue;

  1100. 

  1101.             ts = av_rescale_q(ts, st->time_base,

  1102.                               (AVRational) { FFMAX(1, ast->sample_size),

  1103.                                              AV_TIME_BASE });

  1104. 

  1105.             av_dlog(s, "%"PRId64" %d/%d %"PRId64"\n", ts,

  1106.                     st->time_base.num, st->time_base.den, ast->frame_offset);

  1107.             if (ts < best_ts) {

  1108.                 best_ts           = ts;

  1109.                 best_st           = st;

  1110.                 best_stream_index = i;

  1111.             }

  1112.         }

  1113.         if (!best_st)

  1114.             return AVERROR_EOF;

  1115. 

  1116.         best_ast = best_st->priv_data;

  1117.         best_ts  = av_rescale_q(best_ts,

  1118.                                 (AVRational) { FFMAX(1, best_ast->sample_size),

  1119.                                                AV_TIME_BASE },

  1120.                                 best_st->time_base);

  1121.         if (best_ast->remaining) {

  1122.             i = av_index_search_timestamp(best_st,

  1123.                                           best_ts,

  1124.                                           AVSEEK_FLAG_ANY |

  1125.                                           AVSEEK_FLAG_BACKWARD);

  1126.         } else {

  1127.             i = av_index_search_timestamp(best_st, best_ts, AVSEEK_FLAG_ANY);

  1128.             if (i >= 0)

  1129.                 best_ast->frame_offset = best_st->index_entries[i].timestamp;

  1130.         }

  1131. 

  1132.         if (i >= 0) {

  1133.             int64_t pos = best_st->index_entries[i].pos;

  1134.             pos += best_ast->packet_size - best_ast->remaining;

  1135.             avio_seek(s->pb, pos + 8, SEEK_SET);

  1136. 

  1137.             assert(best_ast->remaining <= best_ast->packet_size);

  1138. 

  1139.             avi->stream_index = best_stream_index;

  1140.             if (!best_ast->remaining)

  1141.                 best_ast->packet_size =

  1142.                 best_ast->remaining   = best_st->index_entries[i].size;

  1143.         }

  1144.     }

  1145. 

  1146. resync:

  1147.     if (avi->stream_index >= 0) {

  1148.         AVStream *st   = s->streams[avi->stream_index];

  1149.         AVIStream *ast = st->priv_data;

  1150.         int size, err;

  1151. 

  1152.         if (get_subtitle_pkt(s, st, pkt))

  1153.             return 0;

  1154. 

  1155.         // minorityreport.AVI block_align=1024 sample_size=1 IMA-ADPCM

  1156.         if (ast->sample_size <= 1)

  1157.             size = INT_MAX;

  1158.         else if (ast->sample_size < 32)

  1159.             // arbitrary multiplier to avoid tiny packets for raw PCM data

  1160.             size = 1024 * ast->sample_size;

  1161.         else

  1162.             size = ast->sample_size;

  1163. 

  1164.         if (size > ast->remaining)

  1165.             size = ast->remaining;

  1166.         avi->last_pkt_pos = avio_tell(pb);

  1167.         err               = av_get_packet(pb, pkt, size);

  1168.         if (err < 0)

  1169.             return err;

  1170. 

  1171.         if (ast->has_pal && pkt->data && pkt->size < (unsigned)INT_MAX / 2) {

  1172.             uint8_t *pal;

  1173.             pal = av_packet_new_side_data(pkt,

  1174.                                           AV_PKT_DATA_PALETTE,

  1175.                                           AVPALETTE_SIZE);

  1176.             if (!pal) {

  1177.                 av_log(s, AV_LOG_ERROR,

  1178.                        "Failed to allocate data for palette\n");

  1179.             } else {

  1180.                 memcpy(pal, ast->pal, AVPALETTE_SIZE);

  1181.                 ast->has_pal = 0;

  1182.             }

  1183.         }

  1184. 

  1185.         if (CONFIG_DV_DEMUXER && avi->dv_demux) {

  1186.             AVBufferRef *avbuf = pkt->buf;

  1187. #if FF_API_DESTRUCT_PACKET

  1188. FF_DISABLE_DEPRECATION_WARNINGS

  1189.             dstr = pkt->destruct;

  1190. FF_ENABLE_DEPRECATION_WARNINGS

  1191. #endif

  1192.             size = avpriv_dv_produce_packet(avi->dv_demux, pkt,

  1193.                                             pkt->data, pkt->size);

  1194. #if FF_API_DESTRUCT_PACKET

  1195. FF_DISABLE_DEPRECATION_WARNINGS

  1196.             pkt->destruct = dstr;

  1197. FF_ENABLE_DEPRECATION_WARNINGS

  1198. #endif

  1199.             pkt->buf    = avbuf;

  1200.             pkt->flags |= AV_PKT_FLAG_KEY;

  1201.             if (size < 0)

  1202.                 av_free_packet(pkt);

  1203.         } else if (st->codec->codec_type == AVMEDIA_TYPE_SUBTITLE &&

  1204.                    !st->codec->codec_tag && read_gab2_sub(st, pkt)) {

  1205.             ast->frame_offset++;

  1206.             avi->stream_index = -1;

  1207.             ast->remaining    = 0;

  1208.             goto resync;

  1209.         } else {

  1210.             /* XXX: How to handle B-frames in AVI? */

  1211.             pkt->dts = ast->frame_offset;

  1212. //                pkt->dts += ast->start;

  1213.             if (ast->sample_size)

  1214.                 pkt->dts /= ast->sample_size;

  1215.             av_dlog(s,

  1216.                     "dts:%"PRId64" offset:%"PRId64" %d/%d smpl_siz:%d "

  1217.                     "base:%d st:%d size:%d\n",

  1218.                     pkt->dts,

  1219.                     ast->frame_offset,

  1220.                     ast->scale,

  1221.                     ast->rate,

  1222.                     ast->sample_size,

  1223.                     AV_TIME_BASE,

  1224.                     avi->stream_index,

  1225.                     size);

  1226.             pkt->stream_index = avi->stream_index;

  1227. 

  1228.             if (st->codec->codec_type == AVMEDIA_TYPE_VIDEO) {

  1229.                 AVIndexEntry *e;

  1230.                 int index;

  1231.                 assert(st->index_entries);

  1232. 

  1233.                 index = av_index_search_timestamp(st, ast->frame_offset, 0);

  1234.                 e     = &st->index_entries[index];

  1235. 

  1236.                 if (index >= 0 && e->timestamp == ast->frame_offset)

  1237.                     if (e->flags & AVINDEX_KEYFRAME)

  1238.                         pkt->flags |= AV_PKT_FLAG_KEY;

  1239.             } else {

  1240.                 pkt->flags |= AV_PKT_FLAG_KEY;

  1241.             }

  1242.             ast->frame_offset += get_duration(ast, pkt->size);

  1243.         }

  1244.         ast->remaining -= err;

  1245.         if (!ast->remaining) {

  1246.             avi->stream_index = -1;

  1247.             ast->packet_size  = 0;

  1248.         }

  1249. 

  1250.         return 0;

  1251.     }

  1252. 

  1253.     if ((err = avi_sync(s, 0)) < 0)

  1254.         return err;

  1255.     goto resync;

  1256. }

  1257. 

  1258. /* XXX: We make the implicit supposition that the positions are sorted

  1259.  * for each stream. */

  1260. static int avi_read_idx1(AVFormatContext *s, int size)

  1261. {

  1262.     AVIContext *avi = s->priv_data;

  1263.     AVIOContext *pb = s->pb;

  1264.     int nb_index_entries, i;

  1265.     AVStream *st;

  1266.     AVIStream *ast;

  1267.     unsigned int index, tag, flags, pos, len, first_packet = 1;

  1268.     unsigned last_pos = -1;

  1269.     int64_t idx1_pos, first_packet_pos = 0, data_offset = 0;

  1270. 

  1271.     nb_index_entries = size / 16;

  1272.     if (nb_index_entries <= 0)

  1273.         return AVERROR_INVALIDDATA;

  1274. 

  1275.     idx1_pos = avio_tell(pb);

  1276.     avio_seek(pb, avi->movi_list + 4, SEEK_SET);

  1277.     if (avi_sync(s, 1) == 0)

  1278.         first_packet_pos = avio_tell(pb) - 8;

  1279.     avi->stream_index = -1;

  1280.     avio_seek(pb, idx1_pos, SEEK_SET);

  1281. 

  1282.     /* Read the entries and sort them in each stream component. */

  1283.     for (i = 0; i < nb_index_entries; i++) {

  1284.         tag   = avio_rl32(pb);

  1285.         flags = avio_rl32(pb);

  1286.         pos   = avio_rl32(pb);

  1287.         len   = avio_rl32(pb);

  1288.         av_dlog(s, "%d: tag=0x%x flags=0x%x pos=0x%x len=%d/",

  1289.                 i, tag, flags, pos, len);

  1290. 

  1291.         index  = ((tag      & 0xff) - '0') * 10;

  1292.         index +=  (tag >> 8 & 0xff) - '0';

  1293.         if (index >= s->nb_streams)

  1294.             continue;

  1295.         st  = s->streams[index];

  1296.         ast = st->priv_data;

  1297. 

  1298.         if (first_packet && first_packet_pos && len) {

  1299.             data_offset  = first_packet_pos - pos;

  1300.             first_packet = 0;

  1301.         }

  1302.         pos += data_offset;

  1303. 

  1304.         av_dlog(s, "%d cum_len=%"PRId64"\n", len, ast->cum_len);

  1305. 

  1306.         if (pb->eof_reached)

  1307.             return AVERROR_INVALIDDATA;

  1308. 

  1309.         if (last_pos == pos)

  1310.             avi->non_interleaved = 1;

  1311.         else if (len || !ast->sample_size)

  1312.             av_add_index_entry(st, pos, ast->cum_len, len, 0,

  1313.                                (flags & AVIIF_INDEX) ? AVINDEX_KEYFRAME : 0);

  1314.         ast->cum_len += get_duration(ast, len);

  1315.         last_pos      = pos;

  1316.     }

  1317.     return 0;

  1318. }

  1319. 

  1320. /* Scan the index and consider any file with streams more than

  1321.  * 2 seconds or 64MB apart non-interleaved. */

  1322. static int check_stream_max_drift(AVFormatContext *s)

  1323. {

  1324.     int64_t min_pos, pos;

  1325.     int i;

  1326.     int *idx = av_mallocz_array(s->nb_streams, sizeof(*idx));

  1327.     if (!idx)

  1328.         return AVERROR(ENOMEM);

  1329. 

  1330.     for (min_pos = pos = 0; min_pos != INT64_MAX; pos = min_pos + 1LU) {

  1331.         int64_t max_dts = INT64_MIN / 2;

  1332.         int64_t min_dts = INT64_MAX / 2;

  1333.         int64_t max_buffer = 0;

  1334. 

  1335.         min_pos = INT64_MAX;

  1336. 

  1337.         for (i = 0; i < s->nb_streams; i++) {

  1338.             AVStream *st = s->streams[i];

  1339.             AVIStream *ast = st->priv_data;

  1340.             int n = st->nb_index_entries;

  1341.             while (idx[i] < n && st->index_entries[idx[i]].pos < pos)

  1342.                 idx[i]++;

  1343.             if (idx[i] < n) {

  1344.                 int64_t dts;

  1345.                 dts = av_rescale_q(st->index_entries[idx[i]].timestamp /

  1346.                                    FFMAX(ast->sample_size, 1),

  1347.                                    st->time_base, AV_TIME_BASE_Q);

  1348.                 min_dts = FFMIN(min_dts, dts);

  1349.                 min_pos = FFMIN(min_pos, st->index_entries[idx[i]].pos);

  1350.             }

  1351.         }

  1352.         for (i = 0; i < s->nb_streams; i++) {

  1353.             AVStream *st = s->streams[i];

  1354.             AVIStream *ast = st->priv_data;

  1355. 

  1356.             if (idx[i] && min_dts != INT64_MAX / 2) {

  1357.                 int64_t dts;

  1358.                 dts = av_rescale_q(st->index_entries[idx[i] - 1].timestamp /

  1359.                                    FFMAX(ast->sample_size, 1),

  1360.                                    st->time_base, AV_TIME_BASE_Q);

  1361.                 max_dts = FFMAX(max_dts, dts);

  1362.                 max_buffer = FFMAX(max_buffer,

  1363.                                    av_rescale(dts - min_dts,

  1364.                                               st->codec->bit_rate,

  1365.                                               AV_TIME_BASE));

  1366.             }

  1367.         }

  1368.         if (max_dts - min_dts > 2 * AV_TIME_BASE ||

  1369.             max_buffer > 1024 * 1024 * 8 * 8) {

  1370.             av_free(idx);

  1371.             return 1;

  1372.         }

  1373.     }

  1374.     av_free(idx);

  1375.     return 0;

  1376. }

  1377. 

  1378. static int guess_ni_flag(AVFormatContext *s)

  1379. {

  1380.     int i;

  1381.     int64_t last_start = 0;

  1382.     int64_t first_end  = INT64_MAX;

  1383.     int64_t oldpos     = avio_tell(s->pb);

  1384. 

  1385.     for (i = 0; i < s->nb_streams; i++) {

  1386.         AVStream *st = s->streams[i];

  1387.         int n        = st->nb_index_entries;

  1388.         unsigned int size;

  1389. 

  1390.         if (n <= 0)

  1391.             continue;

  1392. 

  1393.         if (n >= 2) {

  1394.             int64_t pos = st->index_entries[0].pos;

  1395.             avio_seek(s->pb, pos + 4, SEEK_SET);

  1396.             size = avio_rl32(s->pb);

  1397.             if (pos + size > st->index_entries[1].pos)

  1398.                 last_start = INT64_MAX;

  1399.         }

  1400. 

  1401.         if (st->index_entries[0].pos > last_start)

  1402.             last_start = st->index_entries[0].pos;

  1403.         if (st->index_entries[n - 1].pos < first_end)

  1404.             first_end = st->index_entries[n - 1].pos;

  1405.     }

  1406.     avio_seek(s->pb, oldpos, SEEK_SET);

  1407. 

  1408.     if (last_start > first_end)

  1409.         return 1;

  1410. 

  1411.     return check_stream_max_drift(s);

  1412. }

  1413. 

  1414. static int avi_load_index(AVFormatContext *s)

  1415. {

  1416.     AVIContext *avi = s->priv_data;

  1417.     AVIOContext *pb = s->pb;

  1418.     uint32_t tag, size;

  1419.     int64_t pos = avio_tell(pb);

  1420.     int ret     = -1;

  1421. 

  1422.     if (avio_seek(pb, avi->movi_end, SEEK_SET) < 0)

  1423.         goto the_end; // maybe truncated file

  1424.     av_dlog(s, "movi_end=0x%"PRIx64"\n", avi->movi_end);

  1425.     for (;;) {

  1426.         if (pb->eof_reached)

  1427.             break;

  1428.         tag  = avio_rl32(pb);

  1429.         size = avio_rl32(pb);

  1430.         av_dlog(s, "tag=%c%c%c%c size=0x%x\n",

  1431.                  tag        & 0xff,

  1432.                 (tag >>  8) & 0xff,

  1433.                 (tag >> 16) & 0xff,

  1434.                 (tag >> 24) & 0xff,

  1435.                 size);

  1436. 

  1437.         if (tag == MKTAG('i', 'd', 'x', '1') &&

  1438.             avi_read_idx1(s, size) >= 0) {

  1439.             ret = 0;

  1440.             break;

  1441.         }

  1442. 

  1443.         size += (size & 1);

  1444.         if (avio_skip(pb, size) < 0)

  1445.             break; // something is wrong here

  1446.     }

  1447. 

  1448. the_end:

  1449.     avio_seek(pb, pos, SEEK_SET);

  1450.     return ret;

  1451. }

  1452. 

  1453. static void seek_subtitle(AVStream *st, AVStream *st2, int64_t timestamp)

  1454. {

  1455.     AVIStream *ast2 = st2->priv_data;

  1456.     int64_t ts2     = av_rescale_q(timestamp, st->time_base, st2->time_base);

  1457.     av_free_packet(&ast2->sub_pkt);

  1458.     if (avformat_seek_file(ast2->sub_ctx, 0, INT64_MIN, ts2, ts2, 0) >= 0 ||

  1459.         avformat_seek_file(ast2->sub_ctx, 0, ts2, ts2, INT64_MAX, 0) >= 0)

  1460.         ff_read_packet(ast2->sub_ctx, &ast2->sub_pkt);

  1461. }

  1462. 

  1463. static int avi_read_seek(AVFormatContext *s, int stream_index,

  1464.                          int64_t timestamp, int flags)

  1465. {

  1466.     AVIContext *avi = s->priv_data;

  1467.     AVStream *st;

  1468.     int i, index;

  1469.     int64_t pos;

  1470.     AVIStream *ast;

  1471. 

  1472.     /* Does not matter which stream is requested dv in avi has the

  1473.      * stream information in the first video stream.

  1474.      */

  1475.     if (avi->dv_demux)

  1476.         stream_index = 0;

  1477. 

  1478.     if (!avi->index_loaded) {

  1479.         /* we only load the index on demand */

  1480.         avi_load_index(s);

  1481.         avi->index_loaded = 1;

  1482.     }

  1483. 

  1484.     st    = s->streams[stream_index];

  1485.     ast   = st->priv_data;

  1486.     index = av_index_search_timestamp(st,

  1487.                                       timestamp * FFMAX(ast->sample_size, 1),

  1488.                                       flags);

  1489.     if (index < 0)

  1490.         return AVERROR_INVALIDDATA;

  1491. 

  1492.     /* find the position */

  1493.     pos       = st->index_entries[index].pos;

  1494.     timestamp = st->index_entries[index].timestamp / FFMAX(ast->sample_size, 1);

  1495. 

  1496.     av_dlog(s, "XX %"PRId64" %d %"PRId64"\n",

  1497.             timestamp, index, st->index_entries[index].timestamp);

  1498. 

  1499.     if (CONFIG_DV_DEMUXER && avi->dv_demux) {

  1500.         /* One and only one real stream for DV in AVI, and it has video  */

  1501.         /* offsets. Calling with other stream indexes should have failed */

  1502.         /* the av_index_search_timestamp call above.                     */

  1503. 

  1504.         /* Feed the DV video stream version of the timestamp to the */

  1505.         /* DV demux so it can synthesize correct timestamps.        */

  1506.         ff_dv_offset_reset(avi->dv_demux, timestamp);

  1507. 

  1508.         avio_seek(s->pb, pos, SEEK_SET);

  1509.         avi->stream_index = -1;

  1510.         return 0;

  1511.     }

  1512. 

  1513.     for (i = 0; i < s->nb_streams; i++) {

  1514.         AVStream *st2   = s->streams[i];

  1515.         AVIStream *ast2 = st2->priv_data;

  1516. 

  1517.         ast2->packet_size =

  1518.         ast2->remaining   = 0;

  1519. 

  1520.         if (ast2->sub_ctx) {

  1521.             seek_subtitle(st, st2, timestamp);

  1522.             continue;

  1523.         }

  1524. 

  1525.         if (st2->nb_index_entries <= 0)

  1526.             continue;

  1527. 

  1528. //        assert(st2->codec->block_align);

  1529.         assert((int64_t)st2->time_base.num * ast2->rate ==

  1530.                (int64_t)st2->time_base.den * ast2->scale);

  1531.         index = av_index_search_timestamp(st2,

  1532.                                           av_rescale_q(timestamp,

  1533.                                                        st->time_base,

  1534.                                                        st2->time_base) *

  1535.                                           FFMAX(ast2->sample_size, 1),

  1536.                                           flags | AVSEEK_FLAG_BACKWARD);

  1537.         if (index < 0)

  1538.             index = 0;

  1539. 

  1540.         if (!avi->non_interleaved) {

  1541.             while (index > 0 && st2->index_entries[index].pos > pos)

  1542.                 index--;

  1543.             while (index + 1 < st2->nb_index_entries &&

  1544.                    st2->index_entries[index].pos < pos)

  1545.                 index++;

  1546.         }

  1547. 

  1548.         av_dlog(s, "%"PRId64" %d %"PRId64"\n",

  1549.                 timestamp, index, st2->index_entries[index].timestamp);

  1550.         /* extract the current frame number */

  1551.         ast2->frame_offset = st2->index_entries[index].timestamp;

  1552.     }

  1553. 

  1554.     /* do the seek */

  1555.     avio_seek(s->pb, pos, SEEK_SET);

  1556.     avi->stream_index = -1;

  1557.     return 0;

  1558. }

  1559. 

  1560. static int avi_read_close(AVFormatContext *s)

  1561. {

  1562.     int i;

  1563.     AVIContext *avi = s->priv_data;

  1564. 

  1565.     for (i = 0; i < s->nb_streams; i++) {

  1566.         AVStream *st   = s->streams[i];

  1567.         AVIStream *ast = st->priv_data;

  1568.         if (ast) {

  1569.             if (ast->sub_ctx) {

  1570.                 av_freep(&ast->sub_ctx->pb);

  1571.                 avformat_close_input(&ast->sub_ctx);

  1572.             }

  1573.             av_free(ast->sub_buffer);

  1574.             av_free_packet(&ast->sub_pkt);

  1575.         }

  1576.     }

  1577. 

  1578.     av_free(avi->dv_demux);

  1579. 

  1580.     return 0;

  1581. }

  1582. 

  1583. static int avi_probe(AVProbeData *p)

  1584. {

  1585.     int i;

  1586. 

  1587.     /* check file header */

  1588.     for (i = 0; avi_headers[i][0]; i++)

  1589.         if (!memcmp(p->buf,     avi_headers[i],     4) &&

  1590.             !memcmp(p->buf + 8, avi_headers[i] + 4, 4))

  1591.             return AVPROBE_SCORE_MAX;

  1592. 

  1593.     return 0;

  1594. }

  1595. 

  1596. AVInputFormat ff_avi_demuxer = {

  1597.     .name           = "avi",

  1598.     .long_name      = NULL_IF_CONFIG_SMALL("AVI (Audio Video Interleaved)"),

  1599.     .priv_data_size = sizeof(AVIContext),

  1600.     .extensions     = "avi",

  1601.     .read_probe     = avi_probe,

  1602.     .read_header    = avi_read_header,

  1603.     .read_packet    = avi_read_packet,

  1604.     .read_close     = avi_read_close,

  1605.     .read_seek      = avi_read_seek,

  1606. };