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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/internal.h"

  26. #include "libavutil/intreadwrite.h"

  27. #include "libavutil/mathematics.h"

  28. #include "avformat.h"

  29. #include "avi.h"

  30. #include "dv.h"

  31. #include "internal.h"

  32. #include "riff.h"

  33. 

  34. #undef NDEBUG

  35. #include <assert.h>

  36. 

  37. typedef struct AVIStream {

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

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

  40.     int remaining;

  41.     int packet_size;

  42. 

  43.     uint32_t scale;

  44.     uint32_t rate;

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

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

  47. 

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

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

  50.     int prefix_count;

  51.     uint32_t pal[256];

  52.     int has_pal;

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

  54.                              * the MS dshow demuxer */

  55. 

  56.     AVFormatContext *sub_ctx;

  57.     AVPacket sub_pkt;

  58.     uint8_t *sub_buffer;

  59. } AVIStream;

  60. 

  61. typedef struct {

  62.     int64_t riff_end;

  63.     int64_t movi_end;

  64.     int64_t fsize;

  65.     int64_t movi_list;

  66.     int64_t last_pkt_pos;

  67.     int index_loaded;

  68.     int is_odml;

  69.     int non_interleaved;

  70.     int stream_index;

  71.     DVDemuxContext *dv_demux;

  72.     int odml_depth;

  73. #define MAX_ODML_DEPTH 1000

  74. } AVIContext;

  75. 

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

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

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

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

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

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

  82.     { 0 }

  83. };

  84. 

  85. static const AVMetadataConv avi_metadata_conv[] = {

  86.     { "strn", "title" },

  87.     { 0 },

  88. };

  89. 

  90. static int avi_load_index(AVFormatContext *s);

  91. static int guess_ni_flag(AVFormatContext *s);

  92. 

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

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

  95.             str, tag & 0xff,                             \

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

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

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

  99.             size)

  100. 

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

  102. {

  103.     if (ast->sample_size)

  104.         return len;

  105.     else if (ast->dshow_block_align)

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

  107.     else

  108.         return 1;

  109. }

  110. 

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

  112. {

  113.     AVIContext *avi = s->priv_data;

  114.     char header[8];

  115.     int i;

  116. 

  117.     /* check RIFF header */

  118.     avio_read(pb, header, 4);

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

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

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

  122. 

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

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

  125.             break;

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

  127.         return AVERROR_INVALIDDATA;

  128. 

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

  130.         av_log(s, AV_LOG_INFO,

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

  132. 

  133.     return 0;

  134. }

  135. 

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

  137. {

  138.     AVIContext *avi     = s->priv_data;

  139.     AVIOContext *pb     = s->pb;

  140.     int longs_pre_entry = avio_rl16(pb);

  141.     int index_sub_type  = avio_r8(pb);

  142.     int index_type      = avio_r8(pb);

  143.     int entries_in_use  = avio_rl32(pb);

  144.     int chunk_id        = avio_rl32(pb);

  145.     int64_t base        = avio_rl64(pb);

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

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

  148.     AVStream *st;

  149.     AVIStream *ast;

  150.     int i;

  151.     int64_t last_pos = -1;

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

  153. 

  154.     av_dlog(s,

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

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

  157.             longs_pre_entry,

  158.             index_type,

  159.             entries_in_use,

  160.             chunk_id,

  161.             base);

  162. 

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

  164.         return AVERROR_INVALIDDATA;

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

  166.     ast = st->priv_data;

  167. 

  168.     if (index_sub_type)

  169.         return AVERROR_INVALIDDATA;

  170. 

  171.     avio_rl32(pb);

  172. 

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

  174.         return AVERROR_INVALIDDATA;

  175.     if (index_type > 1)

  176.         return AVERROR_INVALIDDATA;

  177. 

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

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

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

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

  182.             filesize <= 0xFFFFFFFF)

  183.             base &= 0xFFFFFFFF;

  184.         else

  185.             return AVERROR_INVALIDDATA;

  186.     }

  187. 

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

  189.         if (index_type) {

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

  191.             int len     = avio_rl32(pb);

  192.             int key     = len >= 0;

  193.             len &= 0x7FFFFFFF;

  194. 

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

  196. 

  197.             if (pb->eof_reached)

  198.                 return AVERROR_INVALIDDATA;

  199. 

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

  201.                 avi->non_interleaved = 1;

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

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

  204.                                    key ? AVINDEX_KEYFRAME : 0);

  205. 

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

  207.             last_pos      = pos;

  208.         } else {

  209.             int64_t offset, pos;

  210.             int duration;

  211.             offset = avio_rl64(pb);

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

  213.             duration = avio_rl32(pb);

  214. 

  215.             if (pb->eof_reached)

  216.                 return AVERROR_INVALIDDATA;

  217. 

  218.             pos = avio_tell(pb);

  219. 

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

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

  222.                 return AVERROR_INVALIDDATA;

  223.             }

  224. 

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

  226.             avi->odml_depth++;

  227.             read_braindead_odml_indx(s, frame_num);

  228.             avi->odml_depth--;

  229.             frame_num += duration;

  230. 

  231.             avio_seek(pb, pos, SEEK_SET);

  232.         }

  233.     }

  234.     avi->index_loaded = 1;

  235.     return 0;

  236. }

  237. 

  238. static void clean_index(AVFormatContext *s)

  239. {

  240.     int i;

  241.     int64_t j;

  242. 

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

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

  245.         AVIStream *ast = st->priv_data;

  246.         int n          = st->nb_index_entries;

  247.         int max        = ast->sample_size;

  248.         int64_t pos, size, ts;

  249. 

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

  251.             continue;

  252. 

  253.         while (max < 1024)

  254.             max += max;

  255. 

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

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

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

  259. 

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

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

  262.                                AVINDEX_KEYFRAME);

  263.     }

  264. }

  265. 

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

  267.                         uint32_t size)

  268. {

  269.     AVIOContext *pb = s->pb;

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

  271.     char *value;

  272. 

  273.     size += (size & 1);

  274. 

  275.     if (size == UINT_MAX)

  276.         return AVERROR(EINVAL);

  277.     value = av_malloc(size + 1);

  278.     if (!value)

  279.         return AVERROR(ENOMEM);

  280.     avio_read(pb, value, size);

  281.     value[size] = 0;

  282. 

  283.     AV_WL32(key, tag);

  284. 

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

  286.                        AV_DICT_DONT_STRDUP_VAL);

  287. }

  288. 

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

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

  291. 

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

  293. {

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

  295.     int i, day, year;

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

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

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

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

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

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

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

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

  304.             }

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

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

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

  308.     }

  309. }

  310. 

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

  312. {

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

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

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

  316.         switch (tag) {

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

  318.         {

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

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

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

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

  323.                 const char *name = NULL;

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

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

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

  327.                 switch (tag) {

  328.                 case 0x03:

  329.                     name = "maker";

  330.                     break;

  331.                 case 0x04:

  332.                     name = "model";

  333.                     break;

  334.                 case 0x13:

  335.                     name = "creation_time";

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

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

  338.                     break;

  339.                 }

  340.                 if (name)

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

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

  343.             }

  344.             break;

  345.         }

  346.         default:

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

  348.             break;

  349.         }

  350.     }

  351. }

  352. 

  353. static int avi_read_header(AVFormatContext *s)

  354. {

  355.     AVIContext *avi = s->priv_data;

  356.     AVIOContext *pb = s->pb;

  357.     unsigned int tag, tag1, handler;

  358.     int codec_type, stream_index, frame_period;

  359.     unsigned int size;

  360.     int i;

  361.     AVStream *st;

  362.     AVIStream *ast      = NULL;

  363.     int avih_width      = 0, avih_height = 0;

  364.     int amv_file_format = 0;

  365.     uint64_t list_end   = 0;

  366.     int ret;

  367. 

  368.     avi->stream_index = -1;

  369. 

  370.     ret = get_riff(s, pb);

  371.     if (ret < 0)

  372.         return ret;

  373. 

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

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

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

  377. 

  378.     /* first list tag */

  379.     stream_index = -1;

  380.     codec_type   = -1;

  381.     frame_period = 0;

  382.     for (;;) {

  383.         if (pb->eof_reached)

  384.             goto fail;

  385.         tag  = avio_rl32(pb);

  386.         size = avio_rl32(pb);

  387. 

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

  389. 

  390.         switch (tag) {

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

  392.             list_end = avio_tell(pb) + size;

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

  394.             tag1 = avio_rl32(pb);

  395. 

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

  397. 

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

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

  400.                 if (size)

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

  402.                 else

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

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

  405.                 goto end_of_header;

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

  407.                 ff_read_riff_info(s, size - 4);

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

  409.                 avi_read_nikon(s, list_end);

  410. 

  411.             break;

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

  413.         {

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

  415.             size += (size & 1);

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

  417.             avio_skip(pb, size);

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

  419.             break;

  420.         }

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

  422.             avi->is_odml = 1;

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

  424.             break;

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

  426.             amv_file_format = 1;

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

  428.             /* AVI header */

  429.             /* using frame_period is bad idea */

  430.             frame_period = avio_rl32(pb);

  431.             avio_skip(pb, 4);

  432.             avio_rl32(pb);

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

  434. 

  435.             avio_skip(pb, 2 * 4);

  436.             avio_rl32(pb);

  437.             avio_rl32(pb);

  438.             avih_width  = avio_rl32(pb);

  439.             avih_height = avio_rl32(pb);

  440. 

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

  442.             break;

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

  444.             /* stream header */

  445. 

  446.             tag1    = avio_rl32(pb);

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

  448. 

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

  450.                 avio_skip(pb, size - 8);

  451.                 break;

  452.             } else {

  453.                 stream_index++;

  454.                 st = avformat_new_stream(s, NULL);

  455.                 if (!st)

  456.                     goto fail;

  457. 

  458.                 st->id = stream_index;

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

  460.                 if (!ast)

  461.                     goto fail;

  462.                 st->priv_data = ast;

  463.             }

  464.             if (amv_file_format)

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

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

  467. 

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

  469. 

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

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

  472.                 int64_t dv_dur;

  473. 

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

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

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

  477.                     goto fail;

  478. 

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

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

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

  482.                     goto fail;

  483. 

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

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

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

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

  488.                 s->nb_streams = 0;

  489.                 if (CONFIG_DV_DEMUXER) {

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

  491.                     if (!avi->dv_demux)

  492.                         goto fail;

  493.                 } else

  494.                     goto fail;

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

  496.                 avio_skip(pb, 3 * 4);

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

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

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

  500. 

  501.                 dv_dur = avio_rl32(pb);

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

  503.                     dv_dur     *= AV_TIME_BASE;

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

  505.                 }

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

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

  508. 

  509.                 stream_index = s->nb_streams - 1;

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

  511.                 break;

  512.             }

  513. 

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

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

  516. 

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

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

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

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

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

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

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

  524.                 av_log(s, AV_LOG_WARNING,

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

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

  527.                        ast->scale,

  528.                        ast->rate);

  529.                 if (frame_period) {

  530.                     ast->rate  = 1000000;

  531.                     ast->scale = frame_period;

  532.                 } else {

  533.                     ast->rate  = 25;

  534.                     ast->scale = 1;

  535.                 }

  536.             }

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

  538. 

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

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

  541. 

  542.             st->start_time = 0;

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

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

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

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

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

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

  549. 

  550.             switch (tag1) {

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

  552.                 codec_type = AVMEDIA_TYPE_VIDEO;

  553. 

  554.                 ast->sample_size = 0;

  555.                 break;

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

  557.                 codec_type = AVMEDIA_TYPE_AUDIO;

  558.                 break;

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

  560.                 codec_type = AVMEDIA_TYPE_SUBTITLE;

  561.                 break;

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

  563.                 codec_type = AVMEDIA_TYPE_DATA;

  564.                 break;

  565.             default:

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

  567.                 goto fail;

  568.             }

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

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

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

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

  573.             break;

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

  575.             /* stream header */

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

  577.                 avio_skip(pb, size);

  578.             } else {

  579.                 uint64_t cur_pos = avio_tell(pb);

  580.                 if (cur_pos < list_end)

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

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

  583.                 switch (codec_type) {

  584.                 case AVMEDIA_TYPE_VIDEO:

  585.                     if (amv_file_format) {

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

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

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

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

  590.                         avio_skip(pb, size);

  591.                         break;

  592.                     }

  593.                     tag1 = ff_get_bmp_header(pb, st);

  594. 

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

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

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

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

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

  600.                         break;

  601.                     }

  602. 

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

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

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

  606.                                                               FF_INPUT_BUFFER_PADDING_SIZE);

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

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

  609.                             return AVERROR(ENOMEM);

  610.                         }

  611.                         avio_read(pb,

  612.                                   st->codec->extradata,

  613.                                   st->codec->extradata_size);

  614.                     }

  615. 

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

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

  618.                         avio_r8(pb);

  619. 

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

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

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

  623.                      * Libav. */

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

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

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

  627.                         const uint8_t *pal_src;

  628. 

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

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

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

  632. #if HAVE_BIGENDIAN

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

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

  635. #else

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

  637. #endif

  638.                         ast->has_pal = 1;

  639.                     }

  640. 

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

  642. 

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

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

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

  646.                                                             tag1);

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

  648.                      * for generating correct pts. */

  649.                     st->need_parsing = AVSTREAM_PARSE_HEADERS;

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

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

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

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

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

  655. 

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

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

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

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

  660.                                                st->codec->extradata_size +

  661.                                                FF_INPUT_BUFFER_PADDING_SIZE)) < 0) {

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

  663.                             return ret;

  664.                         } else

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

  666.                                    "BottomUp", 9);

  667.                     }

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

  669. 

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

  671.                     break;

  672.                 case AVMEDIA_TYPE_AUDIO:

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

  674.                     if (ret < 0)

  675.                         return ret;

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

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

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

  679.                         av_log(s,

  680.                                AV_LOG_WARNING,

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

  682.                                ast->sample_size,

  683.                                st->codec->block_align);

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

  685.                     }

  686.                     /* 2-aligned

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

  688.                     if (size & 1)

  689.                         avio_skip(pb, 1);

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

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

  692.                     st->need_parsing = AVSTREAM_PARSE_TIMESTAMPS;

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

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

  695.                      * fail. */

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

  697.                         st->codec->extradata_size)

  698.                         st->need_parsing = AVSTREAM_PARSE_NONE;

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

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

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

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

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

  704.                     }

  705.                     if (amv_file_format) {

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

  707.                         ast->dshow_block_align = 0;

  708.                     }

  709.                     break;

  710.                 case AVMEDIA_TYPE_SUBTITLE:

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

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

  713.                     break;

  714.                 default:

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

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

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

  718.                     avio_skip(pb, size);

  719.                     break;

  720.                 }

  721.             }

  722.             break;

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

  724.             i = avio_tell(pb);

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

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

  727.                 (s->error_recognition & AV_EF_EXPLODE))

  728.                 goto fail;

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

  730.             break;

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

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

  733.                 AVRational active, active_aspect;

  734. 

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

  736.                 avio_rl32(pb);

  737.                 avio_rl32(pb);

  738.                 avio_rl32(pb);

  739.                 avio_rl32(pb);

  740.                 avio_rl32(pb);

  741. 

  742.                 active_aspect.den = avio_rl16(pb);

  743.                 active_aspect.num = avio_rl16(pb);

  744.                 active.num        = avio_rl32(pb);

  745.                 active.den        = avio_rl32(pb);

  746.                 avio_rl32(pb); // nbFieldsPerFrame

  747. 

  748.                 if (active_aspect.num && active_aspect.den &&

  749.                     active.num && active.den) {

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

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

  752.                             active_aspect.num, active_aspect.den,

  753.                             active.num, active.den);

  754.                 }

  755.                 size -= 9 * 4;

  756.             }

  757.             avio_skip(pb, size);

  758.             break;

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

  760.             if (s->nb_streams) {

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

  762.                 if (ret < 0)

  763.                     return ret;

  764.                 break;

  765.             }

  766.         default:

  767.             if (size > 1000000) {

  768.                 av_log(s, AV_LOG_ERROR,

  769.                        "Something went wrong during header parsing, "

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

  771.                 if (s->error_recognition & AV_EF_EXPLODE)

  772.                     goto fail;

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

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

  775.                 goto end_of_header;

  776.             }

  777.             /* skip tag */

  778.             size += (size & 1);

  779.             avio_skip(pb, size);

  780.             break;

  781.         }

  782.     }

  783. 

  784. end_of_header:

  785.     /* check stream number */

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

  787. 

  788. fail:

  789.         return AVERROR_INVALIDDATA;

  790.     }

  791. 

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

  793.         avi_load_index(s);

  794.     avi->index_loaded     = 1;

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

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

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

  798.         if (st->nb_index_entries)

  799.             break;

  800.     }

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

  802.         av_log(s, AV_LOG_WARNING,

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

  804.         avi->non_interleaved = 0;

  805.     }

  806. 

  807.     if (avi->non_interleaved) {

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

  809.         clean_index(s);

  810.     }

  811. 

  812.     ff_metadata_conv_ctx(s, NULL, avi_metadata_conv);

  813.     ff_metadata_conv_ctx(s, NULL, ff_riff_info_conv);

  814. 

  815.     return 0;

  816. }

  817. 

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

  819. {

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

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

  822.         uint8_t desc[256];

  823.         int score      = AVPROBE_SCORE_EXTENSION, ret;

  824.         AVIStream *ast = st->priv_data;

  825.         AVInputFormat *sub_demuxer;

  826.         AVRational time_base;

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

  828.                                              pkt->size - 7,

  829.                                              0, NULL, NULL, NULL, NULL);

  830.         AVProbeData pd;

  831.         unsigned int desc_len = avio_rl32(pb);

  832. 

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

  834.             goto error;

  835. 

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

  837.         avio_skip(pb, desc_len - ret);

  838.         if (*desc)

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

  840. 

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

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

  843. 

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

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

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

  847.             goto error;

  848. 

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

  850.             goto error;

  851. 

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

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

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

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

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

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

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

  859.         }

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

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

  862.         return 1;

  863. 

  864. error:

  865.         av_freep(&pb);

  866.     }

  867.     return 0;

  868. }

  869. 

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

  871.                                   AVPacket *pkt)

  872. {

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

  874.     int64_t ts, next_ts, ts_min = INT64_MAX;

  875.     AVStream *st, *sub_st = NULL;

  876.     int i;

  877. 

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

  879.                            AV_TIME_BASE_Q);

  880. 

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

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

  883.         ast = st->priv_data;

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

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

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

  887.                 ts_min = ts;

  888.                 sub_st = st;

  889.             }

  890.         }

  891.     }

  892. 

  893.     if (sub_st) {

  894.         ast               = sub_st->priv_data;

  895.         *pkt              = ast->sub_pkt;

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

  897. 

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

  899.             ast->sub_pkt.data = NULL;

  900.     }

  901.     return sub_st;

  902. }

  903. 

  904. static int get_stream_idx(int *d)

  905. {

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

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

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

  909.     } else {

  910.         return 100; // invalid stream ID

  911.     }

  912. }

  913. 

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

  915. {

  916.     AVIContext *avi = s->priv_data;

  917.     AVIOContext *pb = s->pb;

  918.     int n;

  919.     unsigned int d[8];

  920.     unsigned int size;

  921.     int64_t i, sync;

  922. 

  923. start_sync:

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

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

  926.         int j;

  927. 

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

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

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

  931. 

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

  933. 

  934.         n = get_stream_idx(d + 2);

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

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

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

  938.             continue;

  939. 

  940.         // parse ix##

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

  942.             // parse JUNK

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

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

  945.             avio_skip(pb, size);

  946.             goto start_sync;

  947.         }

  948. 

  949.         // parse stray LIST

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

  951.             avio_skip(pb, 4);

  952.             goto start_sync;

  953.         }

  954. 

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

  956. 

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

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

  959.             continue;

  960. 

  961.         // detect ##ix chunk and skip

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

  963.             avio_skip(pb, size);

  964.             goto start_sync;

  965.         }

  966. 

  967.         // parse ##dc/##wb

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

  969.             AVStream *st;

  970.             AVIStream *ast;

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

  972.             ast = st->priv_data;

  973. 

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

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

  976.                 AVIStream *ast1 = st1->priv_data;

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

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

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

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

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

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

  983.                      !ast1->prefix_count)) {

  984.                     n   = 1;

  985.                     st  = st1;

  986.                     ast = ast1;

  987.                     av_log(s, AV_LOG_WARNING,

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

  989.                 }

  990.             }

  991. 

  992.             if (!avi->dv_demux &&

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

  994.                  // FIXME: needs a little reordering

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

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

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

  998.                 if (!exit_early) {

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

  1000.                 }

  1001.                 avio_skip(pb, size);

  1002.                 goto start_sync;

  1003.             }

  1004. 

  1005.             if (d[2] == 'p' && d[3] == 'c' && size <= 4 * 256 + 4) {

  1006.                 int k    = avio_r8(pb);

  1007.                 int last = (k + avio_r8(pb) - 1) & 0xFF;

  1008. 

  1009.                 avio_rl16(pb); // flags

  1010. 

  1011.                 // b + (g << 8) + (r << 16);

  1012.                 for (; k <= last; k++)

  1013.                     ast->pal[k] = avio_rb32(pb) >> 8;

  1014. 

  1015.                 ast->has_pal = 1;

  1016.                 goto start_sync;

  1017.             } else if (((ast->prefix_count < 5 || sync + 9 > i) &&

  1018.                         d[2] < 128 && d[3] < 128) ||

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

  1020.                        (d[2] == 'd' && d[3] == 'c') ||

  1021.                        (d[2] == 'w' && d[3] == 'b') */) {

  1022.                 if (exit_early)

  1023.                     return 0;

  1024.                 if (d[2] * 256 + d[3] == ast->prefix)

  1025.                     ast->prefix_count++;

  1026.                 else {

  1027.                     ast->prefix       = d[2] * 256 + d[3];

  1028.                     ast->prefix_count = 0;

  1029.                 }

  1030. 

  1031.                 avi->stream_index = n;

  1032.                 ast->packet_size  = size + 8;

  1033.                 ast->remaining    = size;

  1034. 

  1035.                 if (size || !ast->sample_size) {

  1036.                     uint64_t pos = avio_tell(pb) - 8;

  1037.                     if (!st->index_entries || !st->nb_index_entries ||

  1038.                         st->index_entries[st->nb_index_entries - 1].pos < pos) {

  1039.                         av_add_index_entry(st, pos, ast->frame_offset, size,

  1040.                                            0, AVINDEX_KEYFRAME);

  1041.                     }

  1042.                 }

  1043.                 return 0;

  1044.             }

  1045.         }

  1046.     }

  1047. 

  1048.     return AVERROR_EOF;

  1049. }

  1050. 

  1051. static int avi_read_packet(AVFormatContext *s, AVPacket *pkt)

  1052. {

  1053.     AVIContext *avi = s->priv_data;

  1054.     AVIOContext *pb = s->pb;

  1055.     int err;

  1056. #if FF_API_DESTRUCT_PACKET

  1057.     void *dstr;

  1058. #endif

  1059. 

  1060.     if (CONFIG_DV_DEMUXER && avi->dv_demux) {

  1061.         int size = avpriv_dv_get_packet(avi->dv_demux, pkt);

  1062.         if (size >= 0)

  1063.             return size;

  1064.         else

  1065.             goto resync;

  1066.     }

  1067. 

  1068.     if (avi->non_interleaved) {

  1069.         int best_stream_index = 0;

  1070.         AVStream *best_st     = NULL;

  1071.         AVIStream *best_ast;

  1072.         int64_t best_ts = INT64_MAX;

  1073.         int i;

  1074. 

  1075.         for (i = 0; i < s->nb_streams; i++) {

  1076.             AVStream *st   = s->streams[i];

  1077.             AVIStream *ast = st->priv_data;

  1078.             int64_t ts     = ast->frame_offset;

  1079.             int64_t last_ts;

  1080. 

  1081.             if (!st->nb_index_entries)

  1082.                 continue;

  1083. 

  1084.             last_ts = st->index_entries[st->nb_index_entries - 1].timestamp;

  1085.             if (!ast->remaining && ts > last_ts)

  1086.                 continue;

  1087. 

  1088.             ts = av_rescale_q(ts, st->time_base,

  1089.                               (AVRational) { FFMAX(1, ast->sample_size),

  1090.                                              AV_TIME_BASE });

  1091. 

  1092.             av_dlog(s, "%"PRId64" %d/%d %"PRId64"\n", ts,

  1093.                     st->time_base.num, st->time_base.den, ast->frame_offset);

  1094.             if (ts < best_ts) {

  1095.                 best_ts           = ts;

  1096.                 best_st           = st;

  1097.                 best_stream_index = i;

  1098.             }

  1099.         }

  1100.         if (!best_st)

  1101.             return AVERROR_EOF;

  1102. 

  1103.         best_ast = best_st->priv_data;

  1104.         best_ts  = av_rescale_q(best_ts,

  1105.                                 (AVRational) { FFMAX(1, best_ast->sample_size),

  1106.                                                AV_TIME_BASE },

  1107.                                 best_st->time_base);

  1108.         if (best_ast->remaining) {

  1109.             i = av_index_search_timestamp(best_st,

  1110.                                           best_ts,

  1111.                                           AVSEEK_FLAG_ANY |

  1112.                                           AVSEEK_FLAG_BACKWARD);

  1113.         } else {

  1114.             i = av_index_search_timestamp(best_st, best_ts, AVSEEK_FLAG_ANY);

  1115.             if (i >= 0)

  1116.                 best_ast->frame_offset = best_st->index_entries[i].timestamp;

  1117.         }

  1118. 

  1119.         if (i >= 0) {

  1120.             int64_t pos = best_st->index_entries[i].pos;

  1121.             pos += best_ast->packet_size - best_ast->remaining;

  1122.             avio_seek(s->pb, pos + 8, SEEK_SET);

  1123. 

  1124.             assert(best_ast->remaining <= best_ast->packet_size);

  1125. 

  1126.             avi->stream_index = best_stream_index;

  1127.             if (!best_ast->remaining)

  1128.                 best_ast->packet_size =

  1129.                 best_ast->remaining   = best_st->index_entries[i].size;

  1130.         }

  1131.     }

  1132. 

  1133. resync:

  1134.     if (avi->stream_index >= 0) {

  1135.         AVStream *st   = s->streams[avi->stream_index];

  1136.         AVIStream *ast = st->priv_data;

  1137.         int size, err;

  1138. 

  1139.         if (get_subtitle_pkt(s, st, pkt))

  1140.             return 0;

  1141. 

  1142.         // minorityreport.AVI block_align=1024 sample_size=1 IMA-ADPCM

  1143.         if (ast->sample_size <= 1)

  1144.             size = INT_MAX;

  1145.         else if (ast->sample_size < 32)

  1146.             // arbitrary multiplier to avoid tiny packets for raw PCM data

  1147.             size = 1024 * ast->sample_size;

  1148.         else

  1149.             size = ast->sample_size;

  1150. 

  1151.         if (size > ast->remaining)

  1152.             size = ast->remaining;

  1153.         avi->last_pkt_pos = avio_tell(pb);

  1154.         err               = av_get_packet(pb, pkt, size);

  1155.         if (err < 0)

  1156.             return err;

  1157. 

  1158.         if (ast->has_pal && pkt->data && pkt->size < (unsigned)INT_MAX / 2) {

  1159.             uint8_t *pal;

  1160.             pal = av_packet_new_side_data(pkt,

  1161.                                           AV_PKT_DATA_PALETTE,

  1162.                                           AVPALETTE_SIZE);

  1163.             if (!pal) {

  1164.                 av_log(s, AV_LOG_ERROR,

  1165.                        "Failed to allocate data for palette\n");

  1166.             } else {

  1167.                 memcpy(pal, ast->pal, AVPALETTE_SIZE);

  1168.                 ast->has_pal = 0;

  1169.             }

  1170.         }

  1171. 

  1172.         if (CONFIG_DV_DEMUXER && avi->dv_demux) {

  1173.             AVBufferRef *avbuf = pkt->buf;

  1174. #if FF_API_DESTRUCT_PACKET

  1175. FF_DISABLE_DEPRECATION_WARNINGS

  1176.             dstr = pkt->destruct;

  1177. FF_ENABLE_DEPRECATION_WARNINGS

  1178. #endif

  1179.             size = avpriv_dv_produce_packet(avi->dv_demux, pkt,

  1180.                                             pkt->data, pkt->size);

  1181. #if FF_API_DESTRUCT_PACKET

  1182. FF_DISABLE_DEPRECATION_WARNINGS

  1183.             pkt->destruct = dstr;

  1184. FF_ENABLE_DEPRECATION_WARNINGS

  1185. #endif

  1186.             pkt->buf    = avbuf;

  1187.             pkt->flags |= AV_PKT_FLAG_KEY;

  1188.             if (size < 0)

  1189.                 av_free_packet(pkt);

  1190.         } else if (st->codec->codec_type == AVMEDIA_TYPE_SUBTITLE &&

  1191.                    !st->codec->codec_tag && read_gab2_sub(st, pkt)) {

  1192.             ast->frame_offset++;

  1193.             avi->stream_index = -1;

  1194.             ast->remaining    = 0;

  1195.             goto resync;

  1196.         } else {

  1197.             /* XXX: How to handle B-frames in AVI? */

  1198.             pkt->dts = ast->frame_offset;

  1199. //                pkt->dts += ast->start;

  1200.             if (ast->sample_size)

  1201.                 pkt->dts /= ast->sample_size;

  1202.             av_dlog(s,

  1203.                     "dts:%"PRId64" offset:%"PRId64" %d/%d smpl_siz:%d "

  1204.                     "base:%d st:%d size:%d\n",

  1205.                     pkt->dts,

  1206.                     ast->frame_offset,

  1207.                     ast->scale,

  1208.                     ast->rate,

  1209.                     ast->sample_size,

  1210.                     AV_TIME_BASE,

  1211.                     avi->stream_index,

  1212.                     size);

  1213.             pkt->stream_index = avi->stream_index;

  1214. 

  1215.             if (st->codec->codec_type == AVMEDIA_TYPE_VIDEO) {

  1216.                 AVIndexEntry *e;

  1217.                 int index;

  1218.                 assert(st->index_entries);

  1219. 

  1220.                 index = av_index_search_timestamp(st, ast->frame_offset, 0);

  1221.                 e     = &st->index_entries[index];

  1222. 

  1223.                 if (index >= 0 && e->timestamp == ast->frame_offset)

  1224.                     if (e->flags & AVINDEX_KEYFRAME)

  1225.                         pkt->flags |= AV_PKT_FLAG_KEY;

  1226.             } else {

  1227.                 pkt->flags |= AV_PKT_FLAG_KEY;

  1228.             }

  1229.             ast->frame_offset += get_duration(ast, pkt->size);

  1230.         }

  1231.         ast->remaining -= err;

  1232.         if (!ast->remaining) {

  1233.             avi->stream_index = -1;

  1234.             ast->packet_size  = 0;

  1235.         }

  1236. 

  1237.         return 0;

  1238.     }

  1239. 

  1240.     if ((err = avi_sync(s, 0)) < 0)

  1241.         return err;

  1242.     goto resync;

  1243. }

  1244. 

  1245. /* XXX: We make the implicit supposition that the positions are sorted

  1246.  * for each stream. */

  1247. static int avi_read_idx1(AVFormatContext *s, int size)

  1248. {

  1249.     AVIContext *avi = s->priv_data;

  1250.     AVIOContext *pb = s->pb;

  1251.     int nb_index_entries, i;

  1252.     AVStream *st;

  1253.     AVIStream *ast;

  1254.     unsigned int index, tag, flags, pos, len, first_packet = 1;

  1255.     unsigned last_pos = -1;

  1256.     int64_t idx1_pos, first_packet_pos = 0, data_offset = 0;

  1257. 

  1258.     nb_index_entries = size / 16;

  1259.     if (nb_index_entries <= 0)

  1260.         return AVERROR_INVALIDDATA;

  1261. 

  1262.     idx1_pos = avio_tell(pb);

  1263.     avio_seek(pb, avi->movi_list + 4, SEEK_SET);

  1264.     if (avi_sync(s, 1) == 0)

  1265.         first_packet_pos = avio_tell(pb) - 8;

  1266.     avi->stream_index = -1;

  1267.     avio_seek(pb, idx1_pos, SEEK_SET);

  1268. 

  1269.     /* Read the entries and sort them in each stream component. */

  1270.     for (i = 0; i < nb_index_entries; i++) {

  1271.         tag   = avio_rl32(pb);

  1272.         flags = avio_rl32(pb);

  1273.         pos   = avio_rl32(pb);

  1274.         len   = avio_rl32(pb);

  1275.         av_dlog(s, "%d: tag=0x%x flags=0x%x pos=0x%x len=%d/",

  1276.                 i, tag, flags, pos, len);

  1277. 

  1278.         index  = ((tag      & 0xff) - '0') * 10;

  1279.         index +=  (tag >> 8 & 0xff) - '0';

  1280.         if (index >= s->nb_streams)

  1281.             continue;

  1282.         st  = s->streams[index];

  1283.         ast = st->priv_data;

  1284. 

  1285.         if (first_packet && first_packet_pos && len) {

  1286.             data_offset  = first_packet_pos - pos;

  1287.             first_packet = 0;

  1288.         }

  1289.         pos += data_offset;

  1290. 

  1291.         av_dlog(s, "%d cum_len=%"PRId64"\n", len, ast->cum_len);

  1292. 

  1293.         if (pb->eof_reached)

  1294.             return AVERROR_INVALIDDATA;

  1295. 

  1296.         if (last_pos == pos)

  1297.             avi->non_interleaved = 1;

  1298.         else if (len || !ast->sample_size)

  1299.             av_add_index_entry(st, pos, ast->cum_len, len, 0,

  1300.                                (flags & AVIIF_INDEX) ? AVINDEX_KEYFRAME : 0);

  1301.         ast->cum_len += get_duration(ast, len);

  1302.         last_pos      = pos;

  1303.     }

  1304.     return 0;

  1305. }

  1306. 

  1307. static int guess_ni_flag(AVFormatContext *s)

  1308. {

  1309.     int i;

  1310.     int64_t last_start = 0;

  1311.     int64_t first_end  = INT64_MAX;

  1312.     int64_t oldpos     = avio_tell(s->pb);

  1313. 

  1314.     for (i = 0; i < s->nb_streams; i++) {

  1315.         AVStream *st = s->streams[i];

  1316.         int n        = st->nb_index_entries;

  1317.         unsigned int size;

  1318. 

  1319.         if (n <= 0)

  1320.             continue;

  1321. 

  1322.         if (n >= 2) {

  1323.             int64_t pos = st->index_entries[0].pos;

  1324.             avio_seek(s->pb, pos + 4, SEEK_SET);

  1325.             size = avio_rl32(s->pb);

  1326.             if (pos + size > st->index_entries[1].pos)

  1327.                 last_start = INT64_MAX;

  1328.         }

  1329. 

  1330.         if (st->index_entries[0].pos > last_start)

  1331.             last_start = st->index_entries[0].pos;

  1332.         if (st->index_entries[n - 1].pos < first_end)

  1333.             first_end = st->index_entries[n - 1].pos;

  1334.     }

  1335.     avio_seek(s->pb, oldpos, SEEK_SET);

  1336.     return last_start > first_end;

  1337. }

  1338. 

  1339. static int avi_load_index(AVFormatContext *s)

  1340. {

  1341.     AVIContext *avi = s->priv_data;

  1342.     AVIOContext *pb = s->pb;

  1343.     uint32_t tag, size;

  1344.     int64_t pos = avio_tell(pb);

  1345.     int ret     = -1;

  1346. 

  1347.     if (avio_seek(pb, avi->movi_end, SEEK_SET) < 0)

  1348.         goto the_end; // maybe truncated file

  1349.     av_dlog(s, "movi_end=0x%"PRIx64"\n", avi->movi_end);

  1350.     for (;;) {

  1351.         if (pb->eof_reached)

  1352.             break;

  1353.         tag  = avio_rl32(pb);

  1354.         size = avio_rl32(pb);

  1355.         av_dlog(s, "tag=%c%c%c%c size=0x%x\n",

  1356.                  tag        & 0xff,

  1357.                 (tag >>  8) & 0xff,

  1358.                 (tag >> 16) & 0xff,

  1359.                 (tag >> 24) & 0xff,

  1360.                 size);

  1361. 

  1362.         if (tag == MKTAG('i', 'd', 'x', '1') &&

  1363.             avi_read_idx1(s, size) >= 0) {

  1364.             ret = 0;

  1365.             break;

  1366.         }

  1367. 

  1368.         size += (size & 1);

  1369.         if (avio_skip(pb, size) < 0)

  1370.             break; // something is wrong here

  1371.     }

  1372. 

  1373. the_end:

  1374.     avio_seek(pb, pos, SEEK_SET);

  1375.     return ret;

  1376. }

  1377. 

  1378. static void seek_subtitle(AVStream *st, AVStream *st2, int64_t timestamp)

  1379. {

  1380.     AVIStream *ast2 = st2->priv_data;

  1381.     int64_t ts2     = av_rescale_q(timestamp, st->time_base, st2->time_base);

  1382.     av_free_packet(&ast2->sub_pkt);

  1383.     if (avformat_seek_file(ast2->sub_ctx, 0, INT64_MIN, ts2, ts2, 0) >= 0 ||

  1384.         avformat_seek_file(ast2->sub_ctx, 0, ts2, ts2, INT64_MAX, 0) >= 0)

  1385.         ff_read_packet(ast2->sub_ctx, &ast2->sub_pkt);

  1386. }

  1387. 

  1388. static int avi_read_seek(AVFormatContext *s, int stream_index,

  1389.                          int64_t timestamp, int flags)

  1390. {

  1391.     AVIContext *avi = s->priv_data;

  1392.     AVStream *st;

  1393.     int i, index;

  1394.     int64_t pos;

  1395.     AVIStream *ast;

  1396. 

  1397.     /* Does not matter which stream is requested dv in avi has the

  1398.      * stream information in the first video stream.

  1399.      */

  1400.     if (avi->dv_demux)

  1401.         stream_index = 0;

  1402. 

  1403.     if (!avi->index_loaded) {

  1404.         /* we only load the index on demand */

  1405.         avi_load_index(s);

  1406.         avi->index_loaded = 1;

  1407.     }

  1408. 

  1409.     st    = s->streams[stream_index];

  1410.     ast   = st->priv_data;

  1411.     index = av_index_search_timestamp(st,

  1412.                                       timestamp * FFMAX(ast->sample_size, 1),

  1413.                                       flags);

  1414.     if (index < 0)

  1415.         return AVERROR_INVALIDDATA;

  1416. 

  1417.     /* find the position */

  1418.     pos       = st->index_entries[index].pos;

  1419.     timestamp = st->index_entries[index].timestamp / FFMAX(ast->sample_size, 1);

  1420. 

  1421.     av_dlog(s, "XX %"PRId64" %d %"PRId64"\n",

  1422.             timestamp, index, st->index_entries[index].timestamp);

  1423. 

  1424.     if (CONFIG_DV_DEMUXER && avi->dv_demux) {

  1425.         /* One and only one real stream for DV in AVI, and it has video  */

  1426.         /* offsets. Calling with other stream indexes should have failed */

  1427.         /* the av_index_search_timestamp call above.                     */

  1428. 

  1429.         /* Feed the DV video stream version of the timestamp to the */

  1430.         /* DV demux so it can synthesize correct timestamps.        */

  1431.         ff_dv_offset_reset(avi->dv_demux, timestamp);

  1432. 

  1433.         avio_seek(s->pb, pos, SEEK_SET);

  1434.         avi->stream_index = -1;

  1435.         return 0;

  1436.     }

  1437. 

  1438.     for (i = 0; i < s->nb_streams; i++) {

  1439.         AVStream *st2   = s->streams[i];

  1440.         AVIStream *ast2 = st2->priv_data;

  1441. 

  1442.         ast2->packet_size =

  1443.         ast2->remaining   = 0;

  1444. 

  1445.         if (ast2->sub_ctx) {

  1446.             seek_subtitle(st, st2, timestamp);

  1447.             continue;

  1448.         }

  1449. 

  1450.         if (st2->nb_index_entries <= 0)

  1451.             continue;

  1452. 

  1453. //        assert(st2->codec->block_align);

  1454.         assert((int64_t)st2->time_base.num * ast2->rate ==

  1455.                (int64_t)st2->time_base.den * ast2->scale);

  1456.         index = av_index_search_timestamp(st2,

  1457.                                           av_rescale_q(timestamp,

  1458.                                                        st->time_base,

  1459.                                                        st2->time_base) *

  1460.                                           FFMAX(ast2->sample_size, 1),

  1461.                                           flags | AVSEEK_FLAG_BACKWARD);

  1462.         if (index < 0)

  1463.             index = 0;

  1464. 

  1465.         if (!avi->non_interleaved) {

  1466.             while (index > 0 && st2->index_entries[index].pos > pos)

  1467.                 index--;

  1468.             while (index + 1 < st2->nb_index_entries &&

  1469.                    st2->index_entries[index].pos < pos)

  1470.                 index++;

  1471.         }

  1472. 

  1473.         av_dlog(s, "%"PRId64" %d %"PRId64"\n",

  1474.                 timestamp, index, st2->index_entries[index].timestamp);

  1475.         /* extract the current frame number */

  1476.         ast2->frame_offset = st2->index_entries[index].timestamp;

  1477.     }

  1478. 

  1479.     /* do the seek */

  1480.     avio_seek(s->pb, pos, SEEK_SET);

  1481.     avi->stream_index = -1;

  1482.     return 0;

  1483. }

  1484. 

  1485. static int avi_read_close(AVFormatContext *s)

  1486. {

  1487.     int i;

  1488.     AVIContext *avi = s->priv_data;

  1489. 

  1490.     for (i = 0; i < s->nb_streams; i++) {

  1491.         AVStream *st   = s->streams[i];

  1492.         AVIStream *ast = st->priv_data;

  1493.         if (ast) {

  1494.             if (ast->sub_ctx) {

  1495.                 av_freep(&ast->sub_ctx->pb);

  1496.                 avformat_close_input(&ast->sub_ctx);

  1497.             }

  1498.             av_free(ast->sub_buffer);

  1499.             av_free_packet(&ast->sub_pkt);

  1500.         }

  1501.     }

  1502. 

  1503.     av_free(avi->dv_demux);

  1504. 

  1505.     return 0;

  1506. }

  1507. 

  1508. static int avi_probe(AVProbeData *p)

  1509. {

  1510.     int i;

  1511. 

  1512.     /* check file header */

  1513.     for (i = 0; avi_headers[i][0]; i++)

  1514.         if (!memcmp(p->buf,     avi_headers[i],     4) &&

  1515.             !memcmp(p->buf + 8, avi_headers[i] + 4, 4))

  1516.             return AVPROBE_SCORE_MAX;

  1517. 

  1518.     return 0;

  1519. }

  1520. 

  1521. AVInputFormat ff_avi_demuxer = {

  1522.     .name           = "avi",

  1523.     .long_name      = NULL_IF_CONFIG_SMALL("AVI (Audio Video Interleaved)"),

  1524.     .priv_data_size = sizeof(AVIContext),

  1525.     .read_probe     = avi_probe,

  1526.     .read_header    = avi_read_header,

  1527.     .read_packet    = avi_read_packet,

  1528.     .read_close     = avi_read_close,

  1529.     .read_seek      = avi_read_seek,

  1530. };