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FFmpeg/libavformat/avidec.c

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  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 "libavutil/avstring.h"

  23. #include "libavutil/bswap.h"

  24. #include "libavutil/dict.h"

  25. #include "libavutil/intreadwrite.h"

  26. #include "libavutil/mathematics.h"

  27. #include "avformat.h"

  28. #include "avi.h"

  29. #include "dv.h"

  30. #include "internal.h"

  31. #include "riff.h"

  32. 

  33. #undef NDEBUG

  34. #include <assert.h>

  35. 

  36. typedef struct AVIStream {

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

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

  39.     int remaining;

  40.     int packet_size;

  41. 

  42.     uint32_t scale;

  43.     uint32_t rate;

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

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

  46. 

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

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

  49.     int prefix_count;

  50.     uint32_t pal[256];

  51.     int has_pal;

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

  53.                              * the MS dshow demuxer */

  54. 

  55.     AVFormatContext *sub_ctx;

  56.     AVPacket sub_pkt;

  57.     uint8_t *sub_buffer;

  58. } AVIStream;

  59. 

  60. typedef struct {

  61.     int64_t riff_end;

  62.     int64_t movi_end;

  63.     int64_t fsize;

  64.     int64_t movi_list;

  65.     int64_t last_pkt_pos;

  66.     int index_loaded;

  67.     int is_odml;

  68.     int non_interleaved;

  69.     int stream_index;

  70.     DVDemuxContext *dv_demux;

  71.     int odml_depth;

  72. #define MAX_ODML_DEPTH 1000

  73. } AVIContext;

  74. 

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

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

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

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

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

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

  81.     { 0 }

  82. };

  83. 

  84. static const AVMetadataConv avi_metadata_conv[] = {

  85.     { "strn", "title" },

  86.     { 0 },

  87. };

  88. 

  89. static int avi_load_index(AVFormatContext *s);

  90. static int guess_ni_flag(AVFormatContext *s);

  91. 

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

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

  94.             str, tag & 0xff,                             \

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

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

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

  98.             size)

  99. 

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

  101. {

  102.     if (ast->sample_size)

  103.         return len;

  104.     else if (ast->dshow_block_align)

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

  106.     else

  107.         return 1;

  108. }

  109. 

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

  111. {

  112.     AVIContext *avi = s->priv_data;

  113.     char header[8];

  114.     int i;

  115. 

  116.     /* check RIFF header */

  117.     avio_read(pb, header, 4);

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

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

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

  121. 

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

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

  124.             break;

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

  126.         return AVERROR_INVALIDDATA;

  127. 

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

  129.         av_log(s, AV_LOG_INFO,

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

  131. 

  132.     return 0;

  133. }

  134. 

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

  136. {

  137.     AVIContext *avi     = s->priv_data;

  138.     AVIOContext *pb     = s->pb;

  139.     int longs_pre_entry = avio_rl16(pb);

  140.     int index_sub_type  = avio_r8(pb);

  141.     int index_type      = avio_r8(pb);

  142.     int entries_in_use  = avio_rl32(pb);

  143.     int chunk_id        = avio_rl32(pb);

  144.     int64_t base        = avio_rl64(pb);

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

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

  147.     AVStream *st;

  148.     AVIStream *ast;

  149.     int i;

  150.     int64_t last_pos = -1;

  151.     int64_t filesize = avio_size(s->pb);

  152. 

  153.     av_dlog(s,

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

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

  156.             longs_pre_entry,

  157.             index_type,

  158.             entries_in_use,

  159.             chunk_id,

  160.             base);

  161. 

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

  163.         return AVERROR_INVALIDDATA;

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

  165.     ast = st->priv_data;

  166. 

  167.     if (index_sub_type)

  168.         return AVERROR_INVALIDDATA;

  169. 

  170.     avio_rl32(pb);

  171. 

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

  173.         return AVERROR_INVALIDDATA;

  174.     if (index_type > 1)

  175.         return AVERROR_INVALIDDATA;

  176. 

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

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

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

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

  181.             filesize <= 0xFFFFFFFF)

  182.             base &= 0xFFFFFFFF;

  183.         else

  184.             return AVERROR_INVALIDDATA;

  185.     }

  186. 

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

  188.         if (index_type) {

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

  190.             int len     = avio_rl32(pb);

  191.             int key     = len >= 0;

  192.             len &= 0x7FFFFFFF;

  193. 

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

  195. 

  196.             if (pb->eof_reached)

  197.                 return AVERROR_INVALIDDATA;

  198. 

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

  200.                 avi->non_interleaved = 1;

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

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

  203.                                    key ? AVINDEX_KEYFRAME : 0);

  204. 

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

  206.             last_pos      = pos;

  207.         } else {

  208.             int64_t offset, pos;

  209.             int duration;

  210.             offset = avio_rl64(pb);

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

  212.             duration = avio_rl32(pb);

  213. 

  214.             if (pb->eof_reached)

  215.                 return AVERROR_INVALIDDATA;

  216. 

  217.             pos = avio_tell(pb);

  218. 

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

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

  221.                 return AVERROR_INVALIDDATA;

  222.             }

  223. 

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

  225.             avi->odml_depth++;

  226.             read_braindead_odml_indx(s, frame_num);

  227.             avi->odml_depth--;

  228.             frame_num += duration;

  229. 

  230.             avio_seek(pb, pos, SEEK_SET);

  231.         }

  232.     }

  233.     avi->index_loaded = 1;

  234.     return 0;

  235. }

  236. 

  237. static void clean_index(AVFormatContext *s)

  238. {

  239.     int i;

  240.     int64_t j;

  241. 

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

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

  244.         AVIStream *ast = st->priv_data;

  245.         int n          = st->nb_index_entries;

  246.         int max        = ast->sample_size;

  247.         int64_t pos, size, ts;

  248. 

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

  250.             continue;

  251. 

  252.         while (max < 1024)

  253.             max += max;

  254. 

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

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

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

  258. 

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

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

  261.                                AVINDEX_KEYFRAME);

  262.     }

  263. }

  264. 

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

  266.                         uint32_t size)

  267. {

  268.     AVIOContext *pb = s->pb;

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

  270.     char *value;

  271. 

  272.     size += (size & 1);

  273. 

  274.     if (size == UINT_MAX)

  275.         return AVERROR(EINVAL);

  276.     value = av_malloc(size + 1);

  277.     if (!value)

  278.         return AVERROR(ENOMEM);

  279.     avio_read(pb, value, size);

  280.     value[size] = 0;

  281. 

  282.     AV_WL32(key, tag);

  283. 

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

  285.                        AV_DICT_DONT_STRDUP_VAL);

  286. }

  287. 

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

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

  290. 

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

  292. {

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

  294.     int i, day, year;

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

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

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

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

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

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

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

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

  303.             }

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

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

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

  307.     }

  308. }

  309. 

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

  311. {

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

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

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

  315.         switch (tag) {

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

  317.         {

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

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

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

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

  322.                 const char *name = NULL;

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

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

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

  326.                 switch (tag) {

  327.                 case 0x03:

  328.                     name = "maker";

  329.                     break;

  330.                 case 0x04:

  331.                     name = "model";

  332.                     break;

  333.                 case 0x13:

  334.                     name = "creation_time";

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

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

  337.                     break;

  338.                 }

  339.                 if (name)

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

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

  342.             }

  343.             break;

  344.         }

  345.         default:

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

  347.             break;

  348.         }

  349.     }

  350. }

  351. 

  352. static int avi_read_header(AVFormatContext *s)

  353. {

  354.     AVIContext *avi = s->priv_data;

  355.     AVIOContext *pb = s->pb;

  356.     unsigned int tag, tag1, handler;

  357.     int codec_type, stream_index, frame_period;

  358.     unsigned int size;

  359.     int i;

  360.     AVStream *st;

  361.     AVIStream *ast      = NULL;

  362.     int avih_width      = 0, avih_height = 0;

  363.     int amv_file_format = 0;

  364.     uint64_t list_end   = 0;

  365.     int ret;

  366. 

  367.     avi->stream_index = -1;

  368. 

  369.     ret = get_riff(s, pb);

  370.     if (ret < 0)

  371.         return ret;

  372. 

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

  374.     if (avi->fsize <= 0)

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

  376. 

  377.     /* first list tag */

  378.     stream_index = -1;

  379.     codec_type   = -1;

  380.     frame_period = 0;

  381.     for (;;) {

  382.         if (pb->eof_reached)

  383.             goto fail;

  384.         tag  = avio_rl32(pb);

  385.         size = avio_rl32(pb);

  386. 

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

  388. 

  389.         switch (tag) {

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

  391.             list_end = avio_tell(pb) + size;

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

  393.             tag1 = avio_rl32(pb);

  394. 

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

  396. 

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

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

  399.                 if (size)

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

  401.                 else

  402.                     avi->movi_end = avio_size(pb);

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

  404.                 goto end_of_header;

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

  406.                 ff_read_riff_info(s, size - 4);

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

  408.                 avi_read_nikon(s, list_end);

  409. 

  410.             break;

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

  412.         {

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

  414.             size += (size & 1);

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

  416.             avio_skip(pb, size);

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

  418.             break;

  419.         }

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

  421.             avi->is_odml = 1;

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

  423.             break;

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

  425.             amv_file_format = 1;

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

  427.             /* AVI header */

  428.             /* using frame_period is bad idea */

  429.             frame_period = avio_rl32(pb);

  430.             avio_skip(pb, 4);

  431.             avio_rl32(pb);

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

  433. 

  434.             avio_skip(pb, 2 * 4);

  435.             avio_rl32(pb);

  436.             avio_rl32(pb);

  437.             avih_width  = avio_rl32(pb);

  438.             avih_height = avio_rl32(pb);

  439. 

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

  441.             break;

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

  443.             /* stream header */

  444. 

  445.             tag1    = avio_rl32(pb);

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

  447. 

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

  449.                 avio_skip(pb, size - 8);

  450.                 break;

  451.             } else {

  452.                 stream_index++;

  453.                 st = avformat_new_stream(s, NULL);

  454.                 if (!st)

  455.                     goto fail;

  456. 

  457.                 st->id = stream_index;

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

  459.                 if (!ast)

  460.                     goto fail;

  461.                 st->priv_data = ast;

  462.             }

  463.             if (amv_file_format)

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

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

  466. 

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

  468. 

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

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

  471.                 int64_t dv_dur;

  472. 

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

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

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

  476.                     goto fail;

  477. 

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

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

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

  481.                     goto fail;

  482. 

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

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

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

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

  487.                 s->nb_streams = 0;

  488.                 if (CONFIG_DV_DEMUXER) {

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

  490.                     if (!avi->dv_demux)

  491.                         goto fail;

  492.                 }

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

  494.                 avio_skip(pb, 3 * 4);

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

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

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

  498. 

  499.                 dv_dur = avio_rl32(pb);

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

  501.                     dv_dur     *= AV_TIME_BASE;

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

  503.                 }

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

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

  506. 

  507.                 stream_index = s->nb_streams - 1;

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

  509.                 break;

  510.             }

  511. 

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

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

  514. 

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

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

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

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

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

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

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

  522.                 av_log(s, AV_LOG_WARNING,

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

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

  525.                        ast->scale,

  526.                        ast->rate);

  527.                 if (frame_period) {

  528.                     ast->rate  = 1000000;

  529.                     ast->scale = frame_period;

  530.                 } else {

  531.                     ast->rate  = 25;

  532.                     ast->scale = 1;

  533.                 }

  534.             }

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

  536. 

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

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

  539. 

  540.             st->start_time = 0;

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

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

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

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

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

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

  547. 

  548.             switch (tag1) {

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

  550.                 codec_type = AVMEDIA_TYPE_VIDEO;

  551. 

  552.                 ast->sample_size = 0;

  553.                 break;

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

  555.                 codec_type = AVMEDIA_TYPE_AUDIO;

  556.                 break;

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

  558.                 codec_type = AVMEDIA_TYPE_SUBTITLE;

  559.                 break;

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

  561.                 codec_type = AVMEDIA_TYPE_DATA;

  562.                 break;

  563.             default:

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

  565.                 goto fail;

  566.             }

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

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

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

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

  571.             break;

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

  573.             /* stream header */

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

  575.                 avio_skip(pb, size);

  576.             } else {

  577.                 uint64_t cur_pos = avio_tell(pb);

  578.                 if (cur_pos < list_end)

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

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

  581.                 switch (codec_type) {

  582.                 case AVMEDIA_TYPE_VIDEO:

  583.                     if (amv_file_format) {

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

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

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

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

  588.                         avio_skip(pb, size);

  589.                         break;

  590.                     }

  591.                     tag1 = ff_get_bmp_header(pb, st);

  592. 

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

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

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

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

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

  598.                         break;

  599.                     }

  600. 

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

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

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

  604.                                                               FF_INPUT_BUFFER_PADDING_SIZE);

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

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

  607.                             return AVERROR(ENOMEM);

  608.                         }

  609.                         avio_read(pb,

  610.                                   st->codec->extradata,

  611.                                   st->codec->extradata_size);

  612.                     }

  613. 

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

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

  616.                         avio_r8(pb);

  617. 

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

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

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

  621.                      * Libav. */

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

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

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

  625.                         const uint8_t *pal_src;

  626. 

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

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

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

  630. #if HAVE_BIGENDIAN

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

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

  633. #else

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

  635. #endif

  636.                         ast->has_pal = 1;

  637.                     }

  638. 

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

  640. 

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

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

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

  644.                                                             tag1);

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

  646.                      * for generating correct pts. */

  647.                     st->need_parsing = AVSTREAM_PARSE_HEADERS;

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

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

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

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

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

  653. 

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

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

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

  657.                         st->codec->extradata       = av_realloc(st->codec->extradata,

  658.                                                                 st->codec->extradata_size +

  659.                                                                 FF_INPUT_BUFFER_PADDING_SIZE);

  660.                         if (st->codec->extradata)

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

  662.                                    "BottomUp", 9);

  663.                     }

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

  665. 

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

  667.                     break;

  668.                 case AVMEDIA_TYPE_AUDIO:

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

  670.                     if (ret < 0)

  671.                         return ret;

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

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

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

  675.                         av_log(s,

  676.                                AV_LOG_WARNING,

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

  678.                                ast->sample_size,

  679.                                st->codec->block_align);

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

  681.                     }

  682.                     /* 2-aligned

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

  684.                     if (size & 1)

  685.                         avio_skip(pb, 1);

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

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

  688.                     st->need_parsing = AVSTREAM_PARSE_TIMESTAMPS;

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

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

  691.                      * fail. */

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

  693.                         st->codec->extradata_size)

  694.                         st->need_parsing = AVSTREAM_PARSE_NONE;

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

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

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

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

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

  700.                     }

  701.                     if (amv_file_format) {

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

  703.                         ast->dshow_block_align = 0;

  704.                     }

  705.                     break;

  706.                 case AVMEDIA_TYPE_SUBTITLE:

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

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

  709.                     break;

  710.                 default:

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

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

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

  714.                     avio_skip(pb, size);

  715.                     break;

  716.                 }

  717.             }

  718.             break;

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

  720.             i = avio_tell(pb);

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

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

  723.                 (s->error_recognition & AV_EF_EXPLODE))

  724.                 goto fail;

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

  726.             break;

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

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

  729.                 AVRational active, active_aspect;

  730. 

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

  732.                 avio_rl32(pb);

  733.                 avio_rl32(pb);

  734.                 avio_rl32(pb);

  735.                 avio_rl32(pb);

  736.                 avio_rl32(pb);

  737. 

  738.                 active_aspect.den = avio_rl16(pb);

  739.                 active_aspect.num = avio_rl16(pb);

  740.                 active.num        = avio_rl32(pb);

  741.                 active.den        = avio_rl32(pb);

  742.                 avio_rl32(pb); // nbFieldsPerFrame

  743. 

  744.                 if (active_aspect.num && active_aspect.den &&

  745.                     active.num && active.den) {

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

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

  748.                             active_aspect.num, active_aspect.den,

  749.                             active.num, active.den);

  750.                 }

  751.                 size -= 9 * 4;

  752.             }

  753.             avio_skip(pb, size);

  754.             break;

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

  756.             if (s->nb_streams) {

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

  758.                 if (ret < 0)

  759.                     return ret;

  760.                 break;

  761.             }

  762.         default:

  763.             if (size > 1000000) {

  764.                 av_log(s, AV_LOG_ERROR,

  765.                        "Something went wrong during header parsing, "

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

  767.                 if (s->error_recognition & AV_EF_EXPLODE)

  768.                     goto fail;

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

  770.                 avi->movi_end  = avio_size(pb);

  771.                 goto end_of_header;

  772.             }

  773.             /* skip tag */

  774.             size += (size & 1);

  775.             avio_skip(pb, size);

  776.             break;

  777.         }

  778.     }

  779. 

  780. end_of_header:

  781.     /* check stream number */

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

  783. 

  784. fail:

  785.         return AVERROR_INVALIDDATA;

  786.     }

  787. 

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

  789.         avi_load_index(s);

  790.     avi->index_loaded     = 1;

  791.     avi->non_interleaved |= guess_ni_flag(s);

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

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

  794.         if (st->nb_index_entries)

  795.             break;

  796.     }

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

  798.         av_log(s, AV_LOG_WARNING,

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

  800.         avi->non_interleaved = 0;

  801.     }

  802. 

  803.     if (avi->non_interleaved) {

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

  805.         clean_index(s);

  806.     }

  807. 

  808.     ff_metadata_conv_ctx(s, NULL, avi_metadata_conv);

  809.     ff_metadata_conv_ctx(s, NULL, ff_riff_info_conv);

  810. 

  811.     return 0;

  812. }

  813. 

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

  815. {

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

  817.         uint8_t desc[256];

  818.         int score      = AVPROBE_SCORE_EXTENSION, ret;

  819.         AVIStream *ast = st->priv_data;

  820.         AVInputFormat *sub_demuxer;

  821.         AVRational time_base;

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

  823.                                              pkt->size - 7,

  824.                                              0, NULL, NULL, NULL, NULL);

  825.         AVProbeData pd;

  826.         unsigned int desc_len = avio_rl32(pb);

  827. 

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

  829.             goto error;

  830. 

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

  832.         avio_skip(pb, desc_len - ret);

  833.         if (*desc)

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

  835. 

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

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

  838. 

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

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

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

  842.             goto error;

  843. 

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

  845.             goto error;

  846. 

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

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

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

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

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

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

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

  854.         }

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

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

  857.         return 1;

  858. 

  859. error:

  860.         av_freep(&pb);

  861.     }

  862.     return 0;

  863. }

  864. 

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

  866.                                   AVPacket *pkt)

  867. {

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

  869.     int64_t ts, next_ts, ts_min = INT64_MAX;

  870.     AVStream *st, *sub_st = NULL;

  871.     int i;

  872. 

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

  874.                            AV_TIME_BASE_Q);

  875. 

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

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

  878.         ast = st->priv_data;

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

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

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

  882.                 ts_min = ts;

  883.                 sub_st = st;

  884.             }

  885.         }

  886.     }

  887. 

  888.     if (sub_st) {

  889.         ast               = sub_st->priv_data;

  890.         *pkt              = ast->sub_pkt;

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

  892. 

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

  894.             ast->sub_pkt.data = NULL;

  895.     }

  896.     return sub_st;

  897. }

  898. 

  899. static int get_stream_idx(int *d)

  900. {

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

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

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

  904.     } else {

  905.         return 100; // invalid stream ID

  906.     }

  907. }

  908. 

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

  910. {

  911.     AVIContext *avi = s->priv_data;

  912.     AVIOContext *pb = s->pb;

  913.     int n;

  914.     unsigned int d[8];

  915.     unsigned int size;

  916.     int64_t i, sync;

  917. 

  918. start_sync:

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

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

  921.         int j;

  922. 

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

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

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

  926. 

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

  928. 

  929.         n = get_stream_idx(d + 2);

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

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

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

  933.             continue;

  934. 

  935.         // parse ix##

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

  937.             // parse JUNK

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

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

  940.             avio_skip(pb, size);

  941.             goto start_sync;

  942.         }

  943. 

  944.         // parse stray LIST

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

  946.             avio_skip(pb, 4);

  947.             goto start_sync;

  948.         }

  949. 

  950.         n = get_stream_idx(d);

  951. 

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

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

  954.             continue;

  955. 

  956.         // detect ##ix chunk and skip

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

  958.             avio_skip(pb, size);

  959.             goto start_sync;

  960.         }

  961. 

  962.         // parse ##dc/##wb

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

  964.             AVStream *st;

  965.             AVIStream *ast;

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

  967.             ast = st->priv_data;

  968. 

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

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

  971.                 AVIStream *ast1 = st1->priv_data;

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

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

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

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

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

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

  978.                      !ast1->prefix_count)) {

  979.                     n   = 1;

  980.                     st  = st1;

  981.                     ast = ast1;

  982.                     av_log(s, AV_LOG_WARNING,

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

  984.                 }

  985.             }

  986. 

  987.             if ((st->discard >= AVDISCARD_DEFAULT && size == 0)

  988.                 /* || (st->discard >= AVDISCARD_NONKEY && !(pkt->flags & AV_PKT_FLAG_KEY)) */ // FIXME: needs a little reordering

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

  990.                 if (!exit_early) {

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

  992.                 }

  993.                 avio_skip(pb, size);

  994.                 goto start_sync;

  995.             }

  996. 

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

  998.                 int k    = avio_r8(pb);

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

  1000. 

  1001.                 avio_rl16(pb); // flags

  1002. 

  1003.                 // b + (g << 8) + (r << 16);

  1004.                 for (; k <= last; k++)

  1005.                     ast->pal[k] = avio_rb32(pb) >> 8;

  1006. 

  1007.                 ast->has_pal = 1;

  1008.                 goto start_sync;

  1009.             } else if (((ast->prefix_count < 5 || sync + 9 > i) &&

  1010.                         d[2] < 128 && d[3] < 128) ||

  1011.                        d[2] * 256 + d[3] == ast->prefix /* ||

  1012.                        (d[2] == 'd' && d[3] == 'c') ||

  1013.                        (d[2] == 'w' && d[3] == 'b') */) {

  1014.                 if (exit_early)

  1015.                     return 0;

  1016.                 if (d[2] * 256 + d[3] == ast->prefix)

  1017.                     ast->prefix_count++;

  1018.                 else {

  1019.                     ast->prefix       = d[2] * 256 + d[3];

  1020.                     ast->prefix_count = 0;

  1021.                 }

  1022. 

  1023.                 avi->stream_index = n;

  1024.                 ast->packet_size  = size + 8;

  1025.                 ast->remaining    = size;

  1026. 

  1027.                 if (size || !ast->sample_size) {

  1028.                     uint64_t pos = avio_tell(pb) - 8;

  1029.                     if (!st->index_entries || !st->nb_index_entries ||

  1030.                         st->index_entries[st->nb_index_entries - 1].pos < pos) {

  1031.                         av_add_index_entry(st, pos, ast->frame_offset, size,

  1032.                                            0, AVINDEX_KEYFRAME);

  1033.                     }

  1034.                 }

  1035.                 return 0;

  1036.             }

  1037.         }

  1038.     }

  1039. 

  1040.     return AVERROR_EOF;

  1041. }

  1042. 

  1043. static int avi_read_packet(AVFormatContext *s, AVPacket *pkt)

  1044. {

  1045.     AVIContext *avi = s->priv_data;

  1046.     AVIOContext *pb = s->pb;

  1047.     int err;

  1048. #if FF_API_DESTRUCT_PACKET

  1049.     void *dstr;

  1050. #endif

  1051. 

  1052.     if (CONFIG_DV_DEMUXER && avi->dv_demux) {

  1053.         int size = avpriv_dv_get_packet(avi->dv_demux, pkt);

  1054.         if (size >= 0)

  1055.             return size;

  1056.     }

  1057. 

  1058.     if (avi->non_interleaved) {

  1059.         int best_stream_index = 0;

  1060.         AVStream *best_st     = NULL;

  1061.         AVIStream *best_ast;

  1062.         int64_t best_ts = INT64_MAX;

  1063.         int i;

  1064. 

  1065.         for (i = 0; i < s->nb_streams; i++) {

  1066.             AVStream *st   = s->streams[i];

  1067.             AVIStream *ast = st->priv_data;

  1068.             int64_t ts     = ast->frame_offset;

  1069.             int64_t last_ts;

  1070. 

  1071.             if (!st->nb_index_entries)

  1072.                 continue;

  1073. 

  1074.             last_ts = st->index_entries[st->nb_index_entries - 1].timestamp;

  1075.             if (!ast->remaining && ts > last_ts)

  1076.                 continue;

  1077. 

  1078.             ts = av_rescale_q(ts, st->time_base,

  1079.                               (AVRational) { FFMAX(1, ast->sample_size),

  1080.                                              AV_TIME_BASE });

  1081. 

  1082.             av_dlog(s, "%"PRId64" %d/%d %"PRId64"\n", ts,

  1083.                     st->time_base.num, st->time_base.den, ast->frame_offset);

  1084.             if (ts < best_ts) {

  1085.                 best_ts           = ts;

  1086.                 best_st           = st;

  1087.                 best_stream_index = i;

  1088.             }

  1089.         }

  1090.         if (!best_st)

  1091.             return AVERROR_EOF;

  1092. 

  1093.         best_ast = best_st->priv_data;

  1094.         best_ts  = av_rescale_q(best_ts,

  1095.                                 (AVRational) { FFMAX(1, best_ast->sample_size),

  1096.                                                AV_TIME_BASE },

  1097.                                 best_st->time_base);

  1098.         if (best_ast->remaining) {

  1099.             i = av_index_search_timestamp(best_st,

  1100.                                           best_ts,

  1101.                                           AVSEEK_FLAG_ANY |

  1102.                                           AVSEEK_FLAG_BACKWARD);

  1103.         } else {

  1104.             i = av_index_search_timestamp(best_st, best_ts, AVSEEK_FLAG_ANY);

  1105.             if (i >= 0)

  1106.                 best_ast->frame_offset = best_st->index_entries[i].timestamp;

  1107.         }

  1108. 

  1109.         if (i >= 0) {

  1110.             int64_t pos = best_st->index_entries[i].pos;

  1111.             pos += best_ast->packet_size - best_ast->remaining;

  1112.             avio_seek(s->pb, pos + 8, SEEK_SET);

  1113. 

  1114.             assert(best_ast->remaining <= best_ast->packet_size);

  1115. 

  1116.             avi->stream_index = best_stream_index;

  1117.             if (!best_ast->remaining)

  1118.                 best_ast->packet_size =

  1119.                 best_ast->remaining   = best_st->index_entries[i].size;

  1120.         }

  1121.     }

  1122. 

  1123. resync:

  1124.     if (avi->stream_index >= 0) {

  1125.         AVStream *st   = s->streams[avi->stream_index];

  1126.         AVIStream *ast = st->priv_data;

  1127.         int size, err;

  1128. 

  1129.         if (get_subtitle_pkt(s, st, pkt))

  1130.             return 0;

  1131. 

  1132.         // minorityreport.AVI block_align=1024 sample_size=1 IMA-ADPCM

  1133.         if (ast->sample_size <= 1)

  1134.             size = INT_MAX;

  1135.         else if (ast->sample_size < 32)

  1136.             // arbitrary multiplier to avoid tiny packets for raw PCM data

  1137.             size = 1024 * ast->sample_size;

  1138.         else

  1139.             size = ast->sample_size;

  1140. 

  1141.         if (size > ast->remaining)

  1142.             size = ast->remaining;

  1143.         avi->last_pkt_pos = avio_tell(pb);

  1144.         err               = av_get_packet(pb, pkt, size);

  1145.         if (err < 0)

  1146.             return err;

  1147. 

  1148.         if (ast->has_pal && pkt->data && pkt->size < (unsigned)INT_MAX / 2) {

  1149.             uint8_t *pal;

  1150.             pal = av_packet_new_side_data(pkt,

  1151.                                           AV_PKT_DATA_PALETTE,

  1152.                                           AVPALETTE_SIZE);

  1153.             if (!pal) {

  1154.                 av_log(s, AV_LOG_ERROR,

  1155.                        "Failed to allocate data for palette\n");

  1156.             } else {

  1157.                 memcpy(pal, ast->pal, AVPALETTE_SIZE);

  1158.                 ast->has_pal = 0;

  1159.             }

  1160.         }

  1161. 

  1162.         if (CONFIG_DV_DEMUXER && avi->dv_demux) {

  1163.             AVBufferRef *avbuf = pkt->buf;

  1164. #if FF_API_DESTRUCT_PACKET

  1165.             dstr = pkt->destruct;

  1166. #endif

  1167.             size = avpriv_dv_produce_packet(avi->dv_demux, pkt,

  1168.                                             pkt->data, pkt->size);

  1169. #if FF_API_DESTRUCT_PACKET

  1170.             pkt->destruct = dstr;

  1171. #endif

  1172.             pkt->buf    = avbuf;

  1173.             pkt->flags |= AV_PKT_FLAG_KEY;

  1174.             if (size < 0)

  1175.                 av_free_packet(pkt);

  1176.         } else if (st->codec->codec_type == AVMEDIA_TYPE_SUBTITLE &&

  1177.                    !st->codec->codec_tag && read_gab2_sub(st, pkt)) {

  1178.             ast->frame_offset++;

  1179.             avi->stream_index = -1;

  1180.             ast->remaining    = 0;

  1181.             goto resync;

  1182.         } else {

  1183.             /* XXX: How to handle B-frames in AVI? */

  1184.             pkt->dts = ast->frame_offset;

  1185. //                pkt->dts += ast->start;

  1186.             if (ast->sample_size)

  1187.                 pkt->dts /= ast->sample_size;

  1188.             av_dlog(s,

  1189.                     "dts:%"PRId64" offset:%"PRId64" %d/%d smpl_siz:%d "

  1190.                     "base:%d st:%d size:%d\n",

  1191.                     pkt->dts,

  1192.                     ast->frame_offset,

  1193.                     ast->scale,

  1194.                     ast->rate,

  1195.                     ast->sample_size,

  1196.                     AV_TIME_BASE,

  1197.                     avi->stream_index,

  1198.                     size);

  1199.             pkt->stream_index = avi->stream_index;

  1200. 

  1201.             if (st->codec->codec_type == AVMEDIA_TYPE_VIDEO) {

  1202.                 AVIndexEntry *e;

  1203.                 int index;

  1204.                 assert(st->index_entries);

  1205. 

  1206.                 index = av_index_search_timestamp(st, ast->frame_offset, 0);

  1207.                 e     = &st->index_entries[index];

  1208. 

  1209.                 if (index >= 0 && e->timestamp == ast->frame_offset)

  1210.                     if (e->flags & AVINDEX_KEYFRAME)

  1211.                         pkt->flags |= AV_PKT_FLAG_KEY;

  1212.             } else {

  1213.                 pkt->flags |= AV_PKT_FLAG_KEY;

  1214.             }

  1215.             ast->frame_offset += get_duration(ast, pkt->size);

  1216.         }

  1217.         ast->remaining -= err;

  1218.         if (!ast->remaining) {

  1219.             avi->stream_index = -1;

  1220.             ast->packet_size  = 0;

  1221.         }

  1222. 

  1223.         return 0;

  1224.     }

  1225. 

  1226.     if ((err = avi_sync(s, 0)) < 0)

  1227.         return err;

  1228.     goto resync;

  1229. }

  1230. 

  1231. /* XXX: We make the implicit supposition that the positions are sorted

  1232.  * for each stream. */

  1233. static int avi_read_idx1(AVFormatContext *s, int size)

  1234. {

  1235.     AVIContext *avi = s->priv_data;

  1236.     AVIOContext *pb = s->pb;

  1237.     int nb_index_entries, i;

  1238.     AVStream *st;

  1239.     AVIStream *ast;

  1240.     unsigned int index, tag, flags, pos, len, first_packet = 1;

  1241.     unsigned last_pos = -1;

  1242.     int64_t idx1_pos, first_packet_pos = 0, data_offset = 0;

  1243. 

  1244.     nb_index_entries = size / 16;

  1245.     if (nb_index_entries <= 0)

  1246.         return AVERROR_INVALIDDATA;

  1247. 

  1248.     idx1_pos = avio_tell(pb);

  1249.     avio_seek(pb, avi->movi_list + 4, SEEK_SET);

  1250.     if (avi_sync(s, 1) == 0)

  1251.         first_packet_pos = avio_tell(pb) - 8;

  1252.     avi->stream_index = -1;

  1253.     avio_seek(pb, idx1_pos, SEEK_SET);

  1254. 

  1255.     /* Read the entries and sort them in each stream component. */

  1256.     for (i = 0; i < nb_index_entries; i++) {

  1257.         tag   = avio_rl32(pb);

  1258.         flags = avio_rl32(pb);

  1259.         pos   = avio_rl32(pb);

  1260.         len   = avio_rl32(pb);

  1261.         av_dlog(s, "%d: tag=0x%x flags=0x%x pos=0x%x len=%d/",

  1262.                 i, tag, flags, pos, len);

  1263. 

  1264.         index  = ((tag      & 0xff) - '0') * 10;

  1265.         index +=  (tag >> 8 & 0xff) - '0';

  1266.         if (index >= s->nb_streams)

  1267.             continue;

  1268.         st  = s->streams[index];

  1269.         ast = st->priv_data;

  1270. 

  1271.         if (first_packet && first_packet_pos && len) {

  1272.             data_offset  = first_packet_pos - pos;

  1273.             first_packet = 0;

  1274.         }

  1275.         pos += data_offset;

  1276. 

  1277.         av_dlog(s, "%d cum_len=%"PRId64"\n", len, ast->cum_len);

  1278. 

  1279.         if (pb->eof_reached)

  1280.             return AVERROR_INVALIDDATA;

  1281. 

  1282.         if (last_pos == pos)

  1283.             avi->non_interleaved = 1;

  1284.         else if (len || !ast->sample_size)

  1285.             av_add_index_entry(st, pos, ast->cum_len, len, 0,

  1286.                                (flags & AVIIF_INDEX) ? AVINDEX_KEYFRAME : 0);

  1287.         ast->cum_len += get_duration(ast, len);

  1288.         last_pos      = pos;

  1289.     }

  1290.     return 0;

  1291. }

  1292. 

  1293. static int guess_ni_flag(AVFormatContext *s)

  1294. {

  1295.     int i;

  1296.     int64_t last_start = 0;

  1297.     int64_t first_end  = INT64_MAX;

  1298.     int64_t oldpos     = avio_tell(s->pb);

  1299. 

  1300.     for (i = 0; i < s->nb_streams; i++) {

  1301.         AVStream *st = s->streams[i];

  1302.         int n        = st->nb_index_entries;

  1303.         unsigned int size;

  1304. 

  1305.         if (n <= 0)

  1306.             continue;

  1307. 

  1308.         if (n >= 2) {

  1309.             int64_t pos = st->index_entries[0].pos;

  1310.             avio_seek(s->pb, pos + 4, SEEK_SET);

  1311.             size = avio_rl32(s->pb);

  1312.             if (pos + size > st->index_entries[1].pos)

  1313.                 last_start = INT64_MAX;

  1314.         }

  1315. 

  1316.         if (st->index_entries[0].pos > last_start)

  1317.             last_start = st->index_entries[0].pos;

  1318.         if (st->index_entries[n - 1].pos < first_end)

  1319.             first_end = st->index_entries[n - 1].pos;

  1320.     }

  1321.     avio_seek(s->pb, oldpos, SEEK_SET);

  1322.     return last_start > first_end;

  1323. }

  1324. 

  1325. static int avi_load_index(AVFormatContext *s)

  1326. {

  1327.     AVIContext *avi = s->priv_data;

  1328.     AVIOContext *pb = s->pb;

  1329.     uint32_t tag, size;

  1330.     int64_t pos = avio_tell(pb);

  1331.     int ret     = -1;

  1332. 

  1333.     if (avio_seek(pb, avi->movi_end, SEEK_SET) < 0)

  1334.         goto the_end; // maybe truncated file

  1335.     av_dlog(s, "movi_end=0x%"PRIx64"\n", avi->movi_end);

  1336.     for (;;) {

  1337.         if (pb->eof_reached)

  1338.             break;

  1339.         tag  = avio_rl32(pb);

  1340.         size = avio_rl32(pb);

  1341.         av_dlog(s, "tag=%c%c%c%c size=0x%x\n",

  1342.                  tag        & 0xff,

  1343.                 (tag >>  8) & 0xff,

  1344.                 (tag >> 16) & 0xff,

  1345.                 (tag >> 24) & 0xff,

  1346.                 size);

  1347. 

  1348.         if (tag == MKTAG('i', 'd', 'x', '1') &&

  1349.             avi_read_idx1(s, size) >= 0) {

  1350.             ret = 0;

  1351.             break;

  1352.         }

  1353. 

  1354.         size += (size & 1);

  1355.         if (avio_skip(pb, size) < 0)

  1356.             break; // something is wrong here

  1357.     }

  1358. 

  1359. the_end:

  1360.     avio_seek(pb, pos, SEEK_SET);

  1361.     return ret;

  1362. }

  1363. 

  1364. static void seek_subtitle(AVStream *st, AVStream *st2, int64_t timestamp)

  1365. {

  1366.     AVIStream *ast2 = st2->priv_data;

  1367.     int64_t ts2     = av_rescale_q(timestamp, st->time_base, st2->time_base);

  1368.     av_free_packet(&ast2->sub_pkt);

  1369.     if (avformat_seek_file(ast2->sub_ctx, 0, INT64_MIN, ts2, ts2, 0) >= 0 ||

  1370.         avformat_seek_file(ast2->sub_ctx, 0, ts2, ts2, INT64_MAX, 0) >= 0)

  1371.         ff_read_packet(ast2->sub_ctx, &ast2->sub_pkt);

  1372. }

  1373. 

  1374. static int avi_read_seek(AVFormatContext *s, int stream_index,

  1375.                          int64_t timestamp, int flags)

  1376. {

  1377.     AVIContext *avi = s->priv_data;

  1378.     AVStream *st;

  1379.     int i, index;

  1380.     int64_t pos;

  1381.     AVIStream *ast;

  1382. 

  1383.     if (!avi->index_loaded) {

  1384.         /* we only load the index on demand */

  1385.         avi_load_index(s);

  1386.         avi->index_loaded = 1;

  1387.     }

  1388.     assert(stream_index >= 0);

  1389. 

  1390.     st    = s->streams[stream_index];

  1391.     ast   = st->priv_data;

  1392.     index = av_index_search_timestamp(st,

  1393.                                       timestamp * FFMAX(ast->sample_size, 1),

  1394.                                       flags);

  1395.     if (index < 0)

  1396.         return AVERROR_INVALIDDATA;

  1397. 

  1398.     /* find the position */

  1399.     pos       = st->index_entries[index].pos;

  1400.     timestamp = st->index_entries[index].timestamp / FFMAX(ast->sample_size, 1);

  1401. 

  1402.     av_dlog(s, "XX %"PRId64" %d %"PRId64"\n",

  1403.             timestamp, index, st->index_entries[index].timestamp);

  1404. 

  1405.     if (CONFIG_DV_DEMUXER && avi->dv_demux) {

  1406.         /* One and only one real stream for DV in AVI, and it has video  */

  1407.         /* offsets. Calling with other stream indexes should have failed */

  1408.         /* the av_index_search_timestamp call above.                     */

  1409.         assert(stream_index == 0);

  1410. 

  1411.         /* Feed the DV video stream version of the timestamp to the */

  1412.         /* DV demux so it can synthesize correct timestamps.        */

  1413.         ff_dv_offset_reset(avi->dv_demux, timestamp);

  1414. 

  1415.         avio_seek(s->pb, pos, SEEK_SET);

  1416.         avi->stream_index = -1;

  1417.         return 0;

  1418.     }

  1419. 

  1420.     for (i = 0; i < s->nb_streams; i++) {

  1421.         AVStream *st2   = s->streams[i];

  1422.         AVIStream *ast2 = st2->priv_data;

  1423. 

  1424.         ast2->packet_size =

  1425.         ast2->remaining   = 0;

  1426. 

  1427.         if (ast2->sub_ctx) {

  1428.             seek_subtitle(st, st2, timestamp);

  1429.             continue;

  1430.         }

  1431. 

  1432.         if (st2->nb_index_entries <= 0)

  1433.             continue;

  1434. 

  1435. //        assert(st2->codec->block_align);

  1436.         assert((int64_t)st2->time_base.num * ast2->rate ==

  1437.                (int64_t)st2->time_base.den * ast2->scale);

  1438.         index = av_index_search_timestamp(st2,

  1439.                                           av_rescale_q(timestamp,

  1440.                                                        st->time_base,

  1441.                                                        st2->time_base) *

  1442.                                           FFMAX(ast2->sample_size, 1),

  1443.                                           flags | AVSEEK_FLAG_BACKWARD);

  1444.         if (index < 0)

  1445.             index = 0;

  1446. 

  1447.         if (!avi->non_interleaved) {

  1448.             while (index > 0 && st2->index_entries[index].pos > pos)

  1449.                 index--;

  1450.             while (index + 1 < st2->nb_index_entries &&

  1451.                    st2->index_entries[index].pos < pos)

  1452.                 index++;

  1453.         }

  1454. 

  1455.         av_dlog(s, "%"PRId64" %d %"PRId64"\n",

  1456.                 timestamp, index, st2->index_entries[index].timestamp);

  1457.         /* extract the current frame number */

  1458.         ast2->frame_offset = st2->index_entries[index].timestamp;

  1459.     }

  1460. 

  1461.     /* do the seek */

  1462.     avio_seek(s->pb, pos, SEEK_SET);

  1463.     avi->stream_index = -1;

  1464.     return 0;

  1465. }

  1466. 

  1467. static int avi_read_close(AVFormatContext *s)

  1468. {

  1469.     int i;

  1470.     AVIContext *avi = s->priv_data;

  1471. 

  1472.     for (i = 0; i < s->nb_streams; i++) {

  1473.         AVStream *st   = s->streams[i];

  1474.         AVIStream *ast = st->priv_data;

  1475.         if (ast) {

  1476.             if (ast->sub_ctx) {

  1477.                 av_freep(&ast->sub_ctx->pb);

  1478.                 avformat_close_input(&ast->sub_ctx);

  1479.             }

  1480.             av_free(ast->sub_buffer);

  1481.             av_free_packet(&ast->sub_pkt);

  1482.         }

  1483.     }

  1484. 

  1485.     av_free(avi->dv_demux);

  1486. 

  1487.     return 0;

  1488. }

  1489. 

  1490. static int avi_probe(AVProbeData *p)

  1491. {

  1492.     int i;

  1493. 

  1494.     /* check file header */

  1495.     for (i = 0; avi_headers[i][0]; i++)

  1496.         if (!memcmp(p->buf,     avi_headers[i],     4) &&

  1497.             !memcmp(p->buf + 8, avi_headers[i] + 4, 4))

  1498.             return AVPROBE_SCORE_MAX;

  1499. 

  1500.     return 0;

  1501. }

  1502. 

  1503. AVInputFormat ff_avi_demuxer = {

  1504.     .name           = "avi",

  1505.     .long_name      = NULL_IF_CONFIG_SMALL("AVI (Audio Video Interleaved)"),

  1506.     .priv_data_size = sizeof(AVIContext),

  1507.     .read_probe     = avi_probe,

  1508.     .read_header    = avi_read_header,

  1509.     .read_packet    = avi_read_packet,

  1510.     .read_close     = avi_read_close,

  1511.     .read_seek      = avi_read_seek,

  1512. };