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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 <inttypes.h>

  23. 

  24. #include "libavutil/avstring.h"

  25. #include "libavutil/bswap.h"

  26. #include "libavutil/dict.h"

  27. #include "libavutil/internal.h"

  28. #include "libavutil/intreadwrite.h"

  29. #include "libavutil/mathematics.h"

  30. #include "avformat.h"

  31. #include "avi.h"

  32. #include "dv.h"

  33. #include "internal.h"

  34. #include "isom.h"

  35. #include "riff.h"

  36. 

  37. #undef NDEBUG

  38. #include <assert.h>

  39. 

  40. typedef struct AVIStream {

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

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

  43.     int remaining;

  44.     int packet_size;

  45. 

  46.     uint32_t handler;

  47.     uint32_t scale;

  48.     uint32_t rate;

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

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

  51. 

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

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

  54.     int prefix_count;

  55.     uint32_t pal[256];

  56.     int has_pal;

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

  58.                              * the MS dshow demuxer */

  59. 

  60.     AVFormatContext *sub_ctx;

  61.     AVPacket sub_pkt;

  62.     uint8_t *sub_buffer;

  63. } AVIStream;

  64. 

  65. typedef struct AVIContext {

  66.     int64_t riff_end;

  67.     int64_t movi_end;

  68.     int64_t fsize;

  69.     int64_t movi_list;

  70.     int64_t last_pkt_pos;

  71.     int index_loaded;

  72.     int is_odml;

  73.     int non_interleaved;

  74.     int stream_index;

  75.     DVDemuxContext *dv_demux;

  76.     int odml_depth;

  77. #define MAX_ODML_DEPTH 1000

  78. } AVIContext;

  79. 

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

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

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

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

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

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

  86.     { 0 }

  87. };

  88. 

  89. static const AVMetadataConv avi_metadata_conv[] = {

  90.     { "strn", "title" },

  91.     { 0 },

  92. };

  93. 

  94. static int avi_load_index(AVFormatContext *s);

  95. static int guess_ni_flag(AVFormatContext *s);

  96. 

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

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

  99.             str, tag & 0xff,                             \

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

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

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

  103.             size)

  104. 

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

  106. {

  107.     if (ast->sample_size)

  108.         return len;

  109.     else if (ast->dshow_block_align)

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

  111.     else

  112.         return 1;

  113. }

  114. 

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

  116. {

  117.     AVIContext *avi = s->priv_data;

  118.     char header[8];

  119.     int i;

  120. 

  121.     /* check RIFF header */

  122.     avio_read(pb, header, 4);

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

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

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

  126. 

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

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

  129.             break;

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

  131.         return AVERROR_INVALIDDATA;

  132. 

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

  134.         av_log(s, AV_LOG_INFO,

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

  136. 

  137.     return 0;

  138. }

  139. 

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

  141. {

  142.     AVIContext *avi     = s->priv_data;

  143.     AVIOContext *pb     = s->pb;

  144.     int longs_pre_entry = avio_rl16(pb);

  145.     int index_sub_type  = avio_r8(pb);

  146.     int index_type      = avio_r8(pb);

  147.     int entries_in_use  = avio_rl32(pb);

  148.     int chunk_id        = avio_rl32(pb);

  149.     int64_t base        = avio_rl64(pb);

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

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

  152.     AVStream *st;

  153.     AVIStream *ast;

  154.     int i;

  155.     int64_t last_pos = -1;

  156.     int64_t filesize = avi->fsize;

  157. 

  158.     av_dlog(s,

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

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

  161.             longs_pre_entry,

  162.             index_type,

  163.             entries_in_use,

  164.             chunk_id,

  165.             base);

  166. 

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

  168.         return AVERROR_INVALIDDATA;

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

  170.     ast = st->priv_data;

  171. 

  172.     if (index_sub_type)

  173.         return AVERROR_INVALIDDATA;

  174. 

  175.     avio_rl32(pb);

  176. 

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

  178.         return AVERROR_INVALIDDATA;

  179.     if (index_type > 1)

  180.         return AVERROR_INVALIDDATA;

  181. 

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

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

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

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

  186.             filesize <= 0xFFFFFFFF)

  187.             base &= 0xFFFFFFFF;

  188.         else

  189.             return AVERROR_INVALIDDATA;

  190.     }

  191. 

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

  193.         if (index_type) {

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

  195.             int len     = avio_rl32(pb);

  196.             int key     = len >= 0;

  197.             len &= 0x7FFFFFFF;

  198. 

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

  200. 

  201.             if (pb->eof_reached)

  202.                 return AVERROR_INVALIDDATA;

  203. 

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

  205.                 avi->non_interleaved = 1;

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

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

  208.                                    key ? AVINDEX_KEYFRAME : 0);

  209. 

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

  211.             last_pos      = pos;

  212.         } else {

  213.             int64_t offset, pos;

  214.             int duration;

  215.             offset = avio_rl64(pb);

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

  217.             duration = avio_rl32(pb);

  218. 

  219.             if (pb->eof_reached)

  220.                 return AVERROR_INVALIDDATA;

  221. 

  222.             pos = avio_tell(pb);

  223. 

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

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

  226.                 return AVERROR_INVALIDDATA;

  227.             }

  228. 

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

  230.             avi->odml_depth++;

  231.             read_braindead_odml_indx(s, frame_num);

  232.             avi->odml_depth--;

  233.             frame_num += duration;

  234. 

  235.             avio_seek(pb, pos, SEEK_SET);

  236.         }

  237.     }

  238.     avi->index_loaded = 1;

  239.     return 0;

  240. }

  241. 

  242. static void clean_index(AVFormatContext *s)

  243. {

  244.     int i;

  245.     int64_t j;

  246. 

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

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

  249.         AVIStream *ast = st->priv_data;

  250.         int n          = st->nb_index_entries;

  251.         int max        = ast->sample_size;

  252.         int64_t pos, size, ts;

  253. 

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

  255.             continue;

  256. 

  257.         while (max < 1024)

  258.             max += max;

  259. 

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

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

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

  263. 

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

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

  266.                                AVINDEX_KEYFRAME);

  267.     }

  268. }

  269. 

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

  271.                         uint32_t size)

  272. {

  273.     AVIOContext *pb = s->pb;

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

  275.     char *value;

  276. 

  277.     size += (size & 1);

  278. 

  279.     if (size == UINT_MAX)

  280.         return AVERROR(EINVAL);

  281.     value = av_malloc(size + 1);

  282.     if (!value)

  283.         return AVERROR(ENOMEM);

  284.     avio_read(pb, value, size);

  285.     value[size] = 0;

  286. 

  287.     AV_WL32(key, tag);

  288. 

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

  290.                        AV_DICT_DONT_STRDUP_VAL);

  291. }

  292. 

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

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

  295. 

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

  297. {

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

  299.     int i, day, year;

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

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

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

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

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

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

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

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

  308.             }

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

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

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

  312.     }

  313. }

  314. 

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

  316. {

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

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

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

  320.         switch (tag) {

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

  322.         {

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

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

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

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

  327.                 const char *name = NULL;

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

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

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

  331.                 switch (tag) {

  332.                 case 0x03:

  333.                     name = "maker";

  334.                     break;

  335.                 case 0x04:

  336.                     name = "model";

  337.                     break;

  338.                 case 0x13:

  339.                     name = "creation_time";

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

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

  342.                     break;

  343.                 }

  344.                 if (name)

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

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

  347.             }

  348.             break;

  349.         }

  350.         default:

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

  352.             break;

  353.         }

  354.     }

  355. }

  356. 

  357. static int avi_read_header(AVFormatContext *s)

  358. {

  359.     AVIContext *avi = s->priv_data;

  360.     AVIOContext *pb = s->pb;

  361.     unsigned int tag, tag1, handler;

  362.     int codec_type, stream_index, frame_period;

  363.     unsigned int size;

  364.     int i;

  365.     AVStream *st;

  366.     AVIStream *ast      = NULL;

  367.     int avih_width      = 0, avih_height = 0;

  368.     int amv_file_format = 0;

  369.     uint64_t list_end   = 0;

  370.     int ret;

  371. 

  372.     avi->stream_index = -1;

  373. 

  374.     ret = get_riff(s, pb);

  375.     if (ret < 0)

  376.         return ret;

  377. 

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

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

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

  381. 

  382.     /* first list tag */

  383.     stream_index = -1;

  384.     codec_type   = -1;

  385.     frame_period = 0;

  386.     for (;;) {

  387.         if (pb->eof_reached)

  388.             goto fail;

  389.         tag  = avio_rl32(pb);

  390.         size = avio_rl32(pb);

  391. 

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

  393. 

  394.         switch (tag) {

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

  396.             list_end = avio_tell(pb) + size;

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

  398.             tag1 = avio_rl32(pb);

  399. 

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

  401. 

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

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

  404.                 if (size)

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

  406.                 else

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

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

  409.                 goto end_of_header;

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

  411.                 ff_read_riff_info(s, size - 4);

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

  413.                 avi_read_nikon(s, list_end);

  414. 

  415.             break;

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

  417.         {

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

  419.             size += (size & 1);

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

  421.             avio_skip(pb, size);

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

  423.             break;

  424.         }

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

  426.             avi->is_odml = 1;

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

  428.             break;

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

  430.             amv_file_format = 1;

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

  432.             /* AVI header */

  433.             /* using frame_period is bad idea */

  434.             frame_period = avio_rl32(pb);

  435.             avio_skip(pb, 4);

  436.             avio_rl32(pb);

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

  438. 

  439.             avio_skip(pb, 2 * 4);

  440.             avio_rl32(pb);

  441.             avio_rl32(pb);

  442.             avih_width  = avio_rl32(pb);

  443.             avih_height = avio_rl32(pb);

  444. 

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

  446.             break;

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

  448.             /* stream header */

  449. 

  450.             tag1    = avio_rl32(pb);

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

  452. 

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

  454.                 avio_skip(pb, size - 8);

  455.                 break;

  456.             } else {

  457.                 stream_index++;

  458.                 st = avformat_new_stream(s, NULL);

  459.                 if (!st)

  460.                     goto fail;

  461. 

  462.                 st->id = stream_index;

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

  464.                 if (!ast)

  465.                     goto fail;

  466.                 st->priv_data = ast;

  467.             }

  468.             if (amv_file_format)

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

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

  471. 

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

  473. 

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

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

  476.                 int64_t dv_dur;

  477. 

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

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

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

  481.                     goto fail;

  482. 

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

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

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

  486.                     goto fail;

  487. 

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

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

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

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

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

  493.                 s->nb_streams = 0;

  494.                 if (CONFIG_DV_DEMUXER) {

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

  496.                     if (!avi->dv_demux)

  497.                         goto fail;

  498.                 } else

  499.                     goto fail;

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

  501.                 avio_skip(pb, 3 * 4);

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

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

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

  505. 

  506.                 dv_dur = avio_rl32(pb);

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

  508.                     dv_dur     *= AV_TIME_BASE;

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

  510.                 }

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

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

  513. 

  514.                 stream_index = s->nb_streams - 1;

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

  516.                 break;

  517.             }

  518. 

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

  520.             ast->handler = handler;

  521. 

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

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

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

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

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

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

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

  529.                 av_log(s, AV_LOG_WARNING,

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

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

  532.                        ast->scale,

  533.                        ast->rate);

  534.                 if (frame_period) {

  535.                     ast->rate  = 1000000;

  536.                     ast->scale = frame_period;

  537.                 } else {

  538.                     ast->rate  = 25;

  539.                     ast->scale = 1;

  540.                 }

  541.             }

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

  543. 

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

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

  546. 

  547.             st->start_time = 0;

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

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

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

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

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

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

  554. 

  555.             switch (tag1) {

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

  557.                 codec_type = AVMEDIA_TYPE_VIDEO;

  558. 

  559.                 ast->sample_size = 0;

  560.                 break;

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

  562.                 codec_type = AVMEDIA_TYPE_AUDIO;

  563.                 break;

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

  565.                 codec_type = AVMEDIA_TYPE_SUBTITLE;

  566.                 break;

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

  568.                 codec_type = AVMEDIA_TYPE_DATA;

  569.                 break;

  570.             default:

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

  572.                 goto fail;

  573.             }

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

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

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

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

  578.             break;

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

  580.             /* stream header */

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

  582.                 avio_skip(pb, size);

  583.             } else {

  584.                 uint64_t cur_pos = avio_tell(pb);

  585.                 if (cur_pos < list_end)

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

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

  588.                 switch (codec_type) {

  589.                 case AVMEDIA_TYPE_VIDEO:

  590.                     if (amv_file_format) {

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

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

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

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

  595.                         avio_skip(pb, size);

  596.                         break;

  597.                     }

  598.                     tag1 = ff_get_bmp_header(pb, st);

  599. 

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

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

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

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

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

  605.                         break;

  606.                     }

  607. 

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

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

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

  611.                                                               FF_INPUT_BUFFER_PADDING_SIZE);

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

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

  614.                             return AVERROR(ENOMEM);

  615.                         }

  616.                         avio_read(pb,

  617.                                   st->codec->extradata,

  618.                                   st->codec->extradata_size);

  619.                     }

  620. 

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

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

  623.                         avio_r8(pb);

  624. 

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

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

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

  628.                      * Libav. */

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

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

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

  632.                         const uint8_t *pal_src;

  633. 

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

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

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

  637. #if HAVE_BIGENDIAN

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

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

  640. #else

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

  642. #endif

  643.                         ast->has_pal = 1;

  644.                     }

  645. 

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

  647. 

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

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

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

  651.                                                             tag1);

  652.                     /* If codec is not found yet, try with the mov tags. */

  653.                     if (!st->codec->codec_id) {

  654.                         char tag_buf[32];

  655.                         av_get_codec_tag_string(tag_buf, sizeof(tag_buf), tag1);

  656.                         st->codec->codec_id =

  657.                             ff_codec_get_id(ff_codec_movvideo_tags, tag1);

  658.                         if (st->codec->codec_id)

  659.                            av_log(s, AV_LOG_WARNING,

  660.                                   "mov tag found in avi (fourcc %s)\n",

  661.                                   tag_buf);

  662.                     }

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

  664.                      * for generating correct pts. */

  665.                     st->need_parsing = AVSTREAM_PARSE_HEADERS;

  666. 

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

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

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

  670. 

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

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

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

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

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

  676. 

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

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

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

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

  681.                                                st->codec->extradata_size +

  682.                                                FF_INPUT_BUFFER_PADDING_SIZE)) < 0) {

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

  684.                             return ret;

  685.                         } else

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

  687.                                    "BottomUp", 9);

  688.                     }

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

  690. 

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

  692.                     break;

  693.                 case AVMEDIA_TYPE_AUDIO:

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

  695.                     if (ret < 0)

  696.                         return ret;

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

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

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

  700.                         av_log(s,

  701.                                AV_LOG_WARNING,

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

  703.                                ast->sample_size,

  704.                                st->codec->block_align);

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

  706.                     }

  707.                     /* 2-aligned

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

  709.                     if (size & 1)

  710.                         avio_skip(pb, 1);

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

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

  713.                     st->need_parsing = AVSTREAM_PARSE_TIMESTAMPS;

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

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

  716.                      * fail. */

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

  718.                         st->codec->extradata_size)

  719.                         st->need_parsing = AVSTREAM_PARSE_NONE;

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

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

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

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

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

  725.                     }

  726.                     if (amv_file_format) {

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

  728.                         ast->dshow_block_align = 0;

  729.                     }

  730.                     break;

  731.                 case AVMEDIA_TYPE_SUBTITLE:

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

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

  734.                     break;

  735.                 default:

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

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

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

  739.                     avio_skip(pb, size);

  740.                     break;

  741.                 }

  742.             }

  743.             break;

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

  745.             i = avio_tell(pb);

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

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

  748.                 (s->error_recognition & AV_EF_EXPLODE))

  749.                 goto fail;

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

  751.             break;

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

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

  754.                 AVRational active, active_aspect;

  755. 

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

  757.                 avio_rl32(pb);

  758.                 avio_rl32(pb);

  759.                 avio_rl32(pb);

  760.                 avio_rl32(pb);

  761.                 avio_rl32(pb);

  762. 

  763.                 active_aspect.den = avio_rl16(pb);

  764.                 active_aspect.num = avio_rl16(pb);

  765.                 active.num        = avio_rl32(pb);

  766.                 active.den        = avio_rl32(pb);

  767.                 avio_rl32(pb); // nbFieldsPerFrame

  768. 

  769.                 if (active_aspect.num && active_aspect.den &&

  770.                     active.num && active.den) {

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

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

  773.                             active_aspect.num, active_aspect.den,

  774.                             active.num, active.den);

  775.                 }

  776.                 size -= 9 * 4;

  777.             }

  778.             avio_skip(pb, size);

  779.             break;

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

  781.             if (s->nb_streams) {

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

  783.                 if (ret < 0)

  784.                     return ret;

  785.                 break;

  786.             }

  787.         default:

  788.             if (size > 1000000) {

  789.                 av_log(s, AV_LOG_ERROR,

  790.                        "Something went wrong during header parsing, "

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

  792.                 if (s->error_recognition & AV_EF_EXPLODE)

  793.                     goto fail;

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

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

  796.                 goto end_of_header;

  797.             }

  798.             /* skip tag */

  799.             size += (size & 1);

  800.             avio_skip(pb, size);

  801.             break;

  802.         }

  803.     }

  804. 

  805. end_of_header:

  806.     /* check stream number */

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

  808. 

  809. fail:

  810.         return AVERROR_INVALIDDATA;

  811.     }

  812. 

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

  814.         avi_load_index(s);

  815.     avi->index_loaded     = 1;

  816. 

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

  818.         return ret;

  819. 

  820.     avi->non_interleaved |= ret;

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

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

  823.         if (st->nb_index_entries)

  824.             break;

  825.     }

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

  827.         av_log(s, AV_LOG_WARNING,

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

  829.         avi->non_interleaved = 0;

  830.     }

  831. 

  832.     if (avi->non_interleaved) {

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

  834.         clean_index(s);

  835.     }

  836. 

  837.     ff_metadata_conv_ctx(s, NULL, avi_metadata_conv);

  838.     ff_metadata_conv_ctx(s, NULL, ff_riff_info_conv);

  839. 

  840.     return 0;

  841. }

  842. 

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

  844. {

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

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

  847.         uint8_t desc[256];

  848.         int score      = AVPROBE_SCORE_EXTENSION, ret;

  849.         AVIStream *ast = st->priv_data;

  850.         AVInputFormat *sub_demuxer;

  851.         AVRational time_base;

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

  853.                                              pkt->size - 7,

  854.                                              0, NULL, NULL, NULL, NULL);

  855.         AVProbeData pd;

  856.         unsigned int desc_len = avio_rl32(pb);

  857. 

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

  859.             goto error;

  860. 

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

  862.         avio_skip(pb, desc_len - ret);

  863.         if (*desc)

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

  865. 

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

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

  868. 

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

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

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

  872.             goto error;

  873. 

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

  875.             goto error;

  876. 

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

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

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

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

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

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

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

  884.         }

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

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

  887.         return 1;

  888. 

  889. error:

  890.         av_freep(&pb);

  891.     }

  892.     return 0;

  893. }

  894. 

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

  896.                                   AVPacket *pkt)

  897. {

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

  899.     int64_t ts, next_ts, ts_min = INT64_MAX;

  900.     AVStream *st, *sub_st = NULL;

  901.     int i;

  902. 

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

  904.                            AV_TIME_BASE_Q);

  905. 

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

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

  908.         ast = st->priv_data;

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

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

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

  912.                 ts_min = ts;

  913.                 sub_st = st;

  914.             }

  915.         }

  916.     }

  917. 

  918.     if (sub_st) {

  919.         ast               = sub_st->priv_data;

  920.         *pkt              = ast->sub_pkt;

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

  922. 

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

  924.             ast->sub_pkt.data = NULL;

  925.     }

  926.     return sub_st;

  927. }

  928. 

  929. static int get_stream_idx(int *d)

  930. {

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

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

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

  934.     } else {

  935.         return 100; // invalid stream ID

  936.     }

  937. }

  938. 

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

  940. {

  941.     AVIContext *avi = s->priv_data;

  942.     AVIOContext *pb = s->pb;

  943.     int n;

  944.     unsigned int d[8];

  945.     unsigned int size;

  946.     int64_t i, sync;

  947. 

  948. start_sync:

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

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

  951.         int j;

  952. 

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

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

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

  956. 

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

  958. 

  959.         n = get_stream_idx(d + 2);

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

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

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

  963.             continue;

  964. 

  965.         // parse ix##

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

  967.             // parse JUNK

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

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

  970.             avio_skip(pb, size);

  971.             goto start_sync;

  972.         }

  973. 

  974.         // parse stray LIST

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

  976.             avio_skip(pb, 4);

  977.             goto start_sync;

  978.         }

  979. 

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

  981. 

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

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

  984.             continue;

  985. 

  986.         // detect ##ix chunk and skip

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

  988.             avio_skip(pb, size);

  989.             goto start_sync;

  990.         }

  991. 

  992.         // parse ##dc/##wb

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

  994.             AVStream *st;

  995.             AVIStream *ast;

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

  997.             ast = st->priv_data;

  998. 

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

  1000.                 AVStream *st1   = s->streams[1];

  1001.                 AVIStream *ast1 = st1->priv_data;

  1002.                 // workaround for broken small-file-bug402.avi

  1003.                 if (d[2] == 'w' && d[3] == 'b' && n == 0 &&

  1004.                     st->codec->codec_type  == AVMEDIA_TYPE_VIDEO &&

  1005.                     st1->codec->codec_type == AVMEDIA_TYPE_AUDIO &&

  1006.                     ast->prefix == 'd' * 256 + 'c' &&

  1007.                     (d[2] * 256 + d[3] == ast1->prefix ||

  1008.                      !ast1->prefix_count)) {

  1009.                     n   = 1;

  1010.                     st  = st1;

  1011.                     ast = ast1;

  1012.                     av_log(s, AV_LOG_WARNING,

  1013.                            "Invalid stream + prefix combination, assuming audio.\n");

  1014.                 }

  1015.             }

  1016. 

  1017.             if (!avi->dv_demux &&

  1018.                 ((st->discard >= AVDISCARD_DEFAULT && size == 0) /* ||

  1019.                  // FIXME: needs a little reordering

  1020.                  (st->discard >= AVDISCARD_NONKEY &&

  1021.                  !(pkt->flags & AV_PKT_FLAG_KEY)) */

  1022.                 || st->discard >= AVDISCARD_ALL)) {

  1023.                 if (!exit_early) {

  1024.                     ast->frame_offset += get_duration(ast, size);

  1025.                 }

  1026.                 avio_skip(pb, size);

  1027.                 goto start_sync;

  1028.             }

  1029. 

  1030.             if (d[2] == 'p' && d[3] == 'c' && size <= 4 * 256 + 4) {

  1031.                 int k    = avio_r8(pb);

  1032.                 int last = (k + avio_r8(pb) - 1) & 0xFF;

  1033. 

  1034.                 avio_rl16(pb); // flags

  1035. 

  1036.                 // b + (g << 8) + (r << 16);

  1037.                 for (; k <= last; k++)

  1038.                     ast->pal[k] = avio_rb32(pb) >> 8;

  1039. 

  1040.                 ast->has_pal = 1;

  1041.                 goto start_sync;

  1042.             } else if (((ast->prefix_count < 5 || sync + 9 > i) &&

  1043.                         d[2] < 128 && d[3] < 128) ||

  1044.                        d[2] * 256 + d[3] == ast->prefix /* ||

  1045.                        (d[2] == 'd' && d[3] == 'c') ||

  1046.                        (d[2] == 'w' && d[3] == 'b') */) {

  1047.                 if (exit_early)

  1048.                     return 0;

  1049.                 if (d[2] * 256 + d[3] == ast->prefix)

  1050.                     ast->prefix_count++;

  1051.                 else {

  1052.                     ast->prefix       = d[2] * 256 + d[3];

  1053.                     ast->prefix_count = 0;

  1054.                 }

  1055. 

  1056.                 avi->stream_index = n;

  1057.                 ast->packet_size  = size + 8;

  1058.                 ast->remaining    = size;

  1059. 

  1060.                 if (size || !ast->sample_size) {

  1061.                     uint64_t pos = avio_tell(pb) - 8;

  1062.                     if (!st->index_entries || !st->nb_index_entries ||

  1063.                         st->index_entries[st->nb_index_entries - 1].pos < pos) {

  1064.                         av_add_index_entry(st, pos, ast->frame_offset, size,

  1065.                                            0, AVINDEX_KEYFRAME);

  1066.                     }

  1067.                 }

  1068.                 return 0;

  1069.             }

  1070.         }

  1071.     }

  1072. 

  1073.     return AVERROR_EOF;

  1074. }

  1075. 

  1076. static int avi_read_packet(AVFormatContext *s, AVPacket *pkt)

  1077. {

  1078.     AVIContext *avi = s->priv_data;

  1079.     AVIOContext *pb = s->pb;

  1080.     int err;

  1081. #if FF_API_DESTRUCT_PACKET

  1082.     void *dstr;

  1083. #endif

  1084. 

  1085.     if (CONFIG_DV_DEMUXER && avi->dv_demux) {

  1086.         int size = avpriv_dv_get_packet(avi->dv_demux, pkt);

  1087.         if (size >= 0)

  1088.             return size;

  1089.         else

  1090.             goto resync;

  1091.     }

  1092. 

  1093.     if (avi->non_interleaved) {

  1094.         int best_stream_index = 0;

  1095.         AVStream *best_st     = NULL;

  1096.         AVIStream *best_ast;

  1097.         int64_t best_ts = INT64_MAX;

  1098.         int i;

  1099. 

  1100.         for (i = 0; i < s->nb_streams; i++) {

  1101.             AVStream *st   = s->streams[i];

  1102.             AVIStream *ast = st->priv_data;

  1103.             int64_t ts     = ast->frame_offset;

  1104.             int64_t last_ts;

  1105. 

  1106.             if (!st->nb_index_entries)

  1107.                 continue;

  1108. 

  1109.             last_ts = st->index_entries[st->nb_index_entries - 1].timestamp;

  1110.             if (!ast->remaining && ts > last_ts)

  1111.                 continue;

  1112. 

  1113.             ts = av_rescale_q(ts, st->time_base,

  1114.                               (AVRational) { FFMAX(1, ast->sample_size),

  1115.                                              AV_TIME_BASE });

  1116. 

  1117.             av_dlog(s, "%"PRId64" %d/%d %"PRId64"\n", ts,

  1118.                     st->time_base.num, st->time_base.den, ast->frame_offset);

  1119.             if (ts < best_ts) {

  1120.                 best_ts           = ts;

  1121.                 best_st           = st;

  1122.                 best_stream_index = i;

  1123.             }

  1124.         }

  1125.         if (!best_st)

  1126.             return AVERROR_EOF;

  1127. 

  1128.         best_ast = best_st->priv_data;

  1129.         best_ts  = av_rescale_q(best_ts,

  1130.                                 (AVRational) { FFMAX(1, best_ast->sample_size),

  1131.                                                AV_TIME_BASE },

  1132.                                 best_st->time_base);

  1133.         if (best_ast->remaining) {

  1134.             i = av_index_search_timestamp(best_st,

  1135.                                           best_ts,

  1136.                                           AVSEEK_FLAG_ANY |

  1137.                                           AVSEEK_FLAG_BACKWARD);

  1138.         } else {

  1139.             i = av_index_search_timestamp(best_st, best_ts, AVSEEK_FLAG_ANY);

  1140.             if (i >= 0)

  1141.                 best_ast->frame_offset = best_st->index_entries[i].timestamp;

  1142.         }

  1143. 

  1144.         if (i >= 0) {

  1145.             int64_t pos = best_st->index_entries[i].pos;

  1146.             pos += best_ast->packet_size - best_ast->remaining;

  1147.             avio_seek(s->pb, pos + 8, SEEK_SET);

  1148. 

  1149.             assert(best_ast->remaining <= best_ast->packet_size);

  1150. 

  1151.             avi->stream_index = best_stream_index;

  1152.             if (!best_ast->remaining)

  1153.                 best_ast->packet_size =

  1154.                 best_ast->remaining   = best_st->index_entries[i].size;

  1155.         }

  1156.     }

  1157. 

  1158. resync:

  1159.     if (avi->stream_index >= 0) {

  1160.         AVStream *st   = s->streams[avi->stream_index];

  1161.         AVIStream *ast = st->priv_data;

  1162.         int size, err;

  1163. 

  1164.         if (get_subtitle_pkt(s, st, pkt))

  1165.             return 0;

  1166. 

  1167.         // minorityreport.AVI block_align=1024 sample_size=1 IMA-ADPCM

  1168.         if (ast->sample_size <= 1)

  1169.             size = INT_MAX;

  1170.         else if (ast->sample_size < 32)

  1171.             // arbitrary multiplier to avoid tiny packets for raw PCM data

  1172.             size = 1024 * ast->sample_size;

  1173.         else

  1174.             size = ast->sample_size;

  1175. 

  1176.         if (size > ast->remaining)

  1177.             size = ast->remaining;

  1178.         avi->last_pkt_pos = avio_tell(pb);

  1179.         err               = av_get_packet(pb, pkt, size);

  1180.         if (err < 0)

  1181.             return err;

  1182. 

  1183.         if (ast->has_pal && pkt->data && pkt->size < (unsigned)INT_MAX / 2) {

  1184.             uint8_t *pal;

  1185.             pal = av_packet_new_side_data(pkt,

  1186.                                           AV_PKT_DATA_PALETTE,

  1187.                                           AVPALETTE_SIZE);

  1188.             if (!pal) {

  1189.                 av_log(s, AV_LOG_ERROR,

  1190.                        "Failed to allocate data for palette\n");

  1191.             } else {

  1192.                 memcpy(pal, ast->pal, AVPALETTE_SIZE);

  1193.                 ast->has_pal = 0;

  1194.             }

  1195.         }

  1196. 

  1197.         if (CONFIG_DV_DEMUXER && avi->dv_demux) {

  1198.             AVBufferRef *avbuf = pkt->buf;

  1199. #if FF_API_DESTRUCT_PACKET

  1200. FF_DISABLE_DEPRECATION_WARNINGS

  1201.             dstr = pkt->destruct;

  1202. FF_ENABLE_DEPRECATION_WARNINGS

  1203. #endif

  1204.             size = avpriv_dv_produce_packet(avi->dv_demux, pkt,

  1205.                                             pkt->data, pkt->size);

  1206. #if FF_API_DESTRUCT_PACKET

  1207. FF_DISABLE_DEPRECATION_WARNINGS

  1208.             pkt->destruct = dstr;

  1209. FF_ENABLE_DEPRECATION_WARNINGS

  1210. #endif

  1211.             pkt->buf    = avbuf;

  1212.             pkt->flags |= AV_PKT_FLAG_KEY;

  1213.             if (size < 0)

  1214.                 av_free_packet(pkt);

  1215.         } else if (st->codec->codec_type == AVMEDIA_TYPE_SUBTITLE &&

  1216.                    !st->codec->codec_tag && read_gab2_sub(st, pkt)) {

  1217.             ast->frame_offset++;

  1218.             avi->stream_index = -1;

  1219.             ast->remaining    = 0;

  1220.             goto resync;

  1221.         } else {

  1222.             /* XXX: How to handle B-frames in AVI? */

  1223.             pkt->dts = ast->frame_offset;

  1224. //                pkt->dts += ast->start;

  1225.             if (ast->sample_size)

  1226.                 pkt->dts /= ast->sample_size;

  1227.             av_dlog(s,

  1228.                     "dts:%"PRId64" offset:%"PRId64" %d/%d smpl_siz:%d "

  1229.                     "base:%d st:%d size:%d\n",

  1230.                     pkt->dts,

  1231.                     ast->frame_offset,

  1232.                     ast->scale,

  1233.                     ast->rate,

  1234.                     ast->sample_size,

  1235.                     AV_TIME_BASE,

  1236.                     avi->stream_index,

  1237.                     size);

  1238.             pkt->stream_index = avi->stream_index;

  1239. 

  1240.             if (st->codec->codec_type == AVMEDIA_TYPE_VIDEO) {

  1241.                 AVIndexEntry *e;

  1242.                 int index;

  1243.                 assert(st->index_entries);

  1244. 

  1245.                 index = av_index_search_timestamp(st, ast->frame_offset, 0);

  1246.                 e     = &st->index_entries[index];

  1247. 

  1248.                 if (index >= 0 && e->timestamp == ast->frame_offset)

  1249.                     if (e->flags & AVINDEX_KEYFRAME)

  1250.                         pkt->flags |= AV_PKT_FLAG_KEY;

  1251.             } else {

  1252.                 pkt->flags |= AV_PKT_FLAG_KEY;

  1253.             }

  1254.             ast->frame_offset += get_duration(ast, pkt->size);

  1255.         }

  1256.         ast->remaining -= err;

  1257.         if (!ast->remaining) {

  1258.             avi->stream_index = -1;

  1259.             ast->packet_size  = 0;

  1260.         }

  1261. 

  1262.         return 0;

  1263.     }

  1264. 

  1265.     if ((err = avi_sync(s, 0)) < 0)

  1266.         return err;

  1267.     goto resync;

  1268. }

  1269. 

  1270. /* XXX: We make the implicit supposition that the positions are sorted

  1271.  * for each stream. */

  1272. static int avi_read_idx1(AVFormatContext *s, int size)

  1273. {

  1274.     AVIContext *avi = s->priv_data;

  1275.     AVIOContext *pb = s->pb;

  1276.     int nb_index_entries, i;

  1277.     AVStream *st;

  1278.     AVIStream *ast;

  1279.     unsigned int index, tag, flags, pos, len, first_packet = 1;

  1280.     unsigned last_pos = -1;

  1281.     int64_t idx1_pos, first_packet_pos = 0, data_offset = 0;

  1282. 

  1283.     nb_index_entries = size / 16;

  1284.     if (nb_index_entries <= 0)

  1285.         return AVERROR_INVALIDDATA;

  1286. 

  1287.     idx1_pos = avio_tell(pb);

  1288.     avio_seek(pb, avi->movi_list + 4, SEEK_SET);

  1289.     if (avi_sync(s, 1) == 0)

  1290.         first_packet_pos = avio_tell(pb) - 8;

  1291.     avi->stream_index = -1;

  1292.     avio_seek(pb, idx1_pos, SEEK_SET);

  1293. 

  1294.     /* Read the entries and sort them in each stream component. */

  1295.     for (i = 0; i < nb_index_entries; i++) {

  1296.         tag   = avio_rl32(pb);

  1297.         flags = avio_rl32(pb);

  1298.         pos   = avio_rl32(pb);

  1299.         len   = avio_rl32(pb);

  1300.         av_dlog(s, "%d: tag=0x%x flags=0x%x pos=0x%x len=%d/",

  1301.                 i, tag, flags, pos, len);

  1302. 

  1303.         index  = ((tag      & 0xff) - '0') * 10;

  1304.         index +=  (tag >> 8 & 0xff) - '0';

  1305.         if (index >= s->nb_streams)

  1306.             continue;

  1307.         st  = s->streams[index];

  1308.         ast = st->priv_data;

  1309. 

  1310.         if (first_packet && first_packet_pos && len) {

  1311.             data_offset  = first_packet_pos - pos;

  1312.             first_packet = 0;

  1313.         }

  1314.         pos += data_offset;

  1315. 

  1316.         av_dlog(s, "%d cum_len=%"PRId64"\n", len, ast->cum_len);

  1317. 

  1318.         if (pb->eof_reached)

  1319.             return AVERROR_INVALIDDATA;

  1320. 

  1321.         if (last_pos == pos)

  1322.             avi->non_interleaved = 1;

  1323.         else if (len || !ast->sample_size)

  1324.             av_add_index_entry(st, pos, ast->cum_len, len, 0,

  1325.                                (flags & AVIIF_INDEX) ? AVINDEX_KEYFRAME : 0);

  1326.         ast->cum_len += get_duration(ast, len);

  1327.         last_pos      = pos;

  1328.     }

  1329.     return 0;

  1330. }

  1331. 

  1332. /* Scan the index and consider any file with streams more than

  1333.  * 2 seconds or 64MB apart non-interleaved. */

  1334. static int check_stream_max_drift(AVFormatContext *s)

  1335. {

  1336.     int64_t min_pos, pos;

  1337.     int i;

  1338.     int *idx = av_mallocz_array(s->nb_streams, sizeof(*idx));

  1339.     if (!idx)

  1340.         return AVERROR(ENOMEM);

  1341. 

  1342.     for (min_pos = pos = 0; min_pos != INT64_MAX; pos = min_pos + 1LU) {

  1343.         int64_t max_dts = INT64_MIN / 2;

  1344.         int64_t min_dts = INT64_MAX / 2;

  1345.         int64_t max_buffer = 0;

  1346. 

  1347.         min_pos = INT64_MAX;

  1348. 

  1349.         for (i = 0; i < s->nb_streams; i++) {

  1350.             AVStream *st = s->streams[i];

  1351.             AVIStream *ast = st->priv_data;

  1352.             int n = st->nb_index_entries;

  1353.             while (idx[i] < n && st->index_entries[idx[i]].pos < pos)

  1354.                 idx[i]++;

  1355.             if (idx[i] < n) {

  1356.                 int64_t dts;

  1357.                 dts = av_rescale_q(st->index_entries[idx[i]].timestamp /

  1358.                                    FFMAX(ast->sample_size, 1),

  1359.                                    st->time_base, AV_TIME_BASE_Q);

  1360.                 min_dts = FFMIN(min_dts, dts);

  1361.                 min_pos = FFMIN(min_pos, st->index_entries[idx[i]].pos);

  1362.             }

  1363.         }

  1364.         for (i = 0; i < s->nb_streams; i++) {

  1365.             AVStream *st = s->streams[i];

  1366.             AVIStream *ast = st->priv_data;

  1367. 

  1368.             if (idx[i] && min_dts != INT64_MAX / 2) {

  1369.                 int64_t dts;

  1370.                 dts = av_rescale_q(st->index_entries[idx[i] - 1].timestamp /

  1371.                                    FFMAX(ast->sample_size, 1),

  1372.                                    st->time_base, AV_TIME_BASE_Q);

  1373.                 max_dts = FFMAX(max_dts, dts);

  1374.                 max_buffer = FFMAX(max_buffer,

  1375.                                    av_rescale(dts - min_dts,

  1376.                                               st->codec->bit_rate,

  1377.                                               AV_TIME_BASE));

  1378.             }

  1379.         }

  1380.         if (max_dts - min_dts > 2 * AV_TIME_BASE ||

  1381.             max_buffer > 1024 * 1024 * 8 * 8) {

  1382.             av_free(idx);

  1383.             return 1;

  1384.         }

  1385.     }

  1386.     av_free(idx);

  1387.     return 0;

  1388. }

  1389. 

  1390. static int guess_ni_flag(AVFormatContext *s)

  1391. {

  1392.     int i;

  1393.     int64_t last_start = 0;

  1394.     int64_t first_end  = INT64_MAX;

  1395.     int64_t oldpos     = avio_tell(s->pb);

  1396. 

  1397.     for (i = 0; i < s->nb_streams; i++) {

  1398.         AVStream *st = s->streams[i];

  1399.         int n        = st->nb_index_entries;

  1400.         unsigned int size;

  1401. 

  1402.         if (n <= 0)

  1403.             continue;

  1404. 

  1405.         if (n >= 2) {

  1406.             int64_t pos = st->index_entries[0].pos;

  1407.             avio_seek(s->pb, pos + 4, SEEK_SET);

  1408.             size = avio_rl32(s->pb);

  1409.             if (pos + size > st->index_entries[1].pos)

  1410.                 last_start = INT64_MAX;

  1411.         }

  1412. 

  1413.         if (st->index_entries[0].pos > last_start)

  1414.             last_start = st->index_entries[0].pos;

  1415.         if (st->index_entries[n - 1].pos < first_end)

  1416.             first_end = st->index_entries[n - 1].pos;

  1417.     }

  1418.     avio_seek(s->pb, oldpos, SEEK_SET);

  1419. 

  1420.     if (last_start > first_end)

  1421.         return 1;

  1422. 

  1423.     return check_stream_max_drift(s);

  1424. }

  1425. 

  1426. static int avi_load_index(AVFormatContext *s)

  1427. {

  1428.     AVIContext *avi = s->priv_data;

  1429.     AVIOContext *pb = s->pb;

  1430.     uint32_t tag, size;

  1431.     int64_t pos = avio_tell(pb);

  1432.     int ret     = -1;

  1433. 

  1434.     if (avio_seek(pb, avi->movi_end, SEEK_SET) < 0)

  1435.         goto the_end; // maybe truncated file

  1436.     av_dlog(s, "movi_end=0x%"PRIx64"\n", avi->movi_end);

  1437.     for (;;) {

  1438.         if (pb->eof_reached)

  1439.             break;

  1440.         tag  = avio_rl32(pb);

  1441.         size = avio_rl32(pb);

  1442.         av_dlog(s, "tag=%c%c%c%c size=0x%x\n",

  1443.                  tag        & 0xff,

  1444.                 (tag >>  8) & 0xff,

  1445.                 (tag >> 16) & 0xff,

  1446.                 (tag >> 24) & 0xff,

  1447.                 size);

  1448. 

  1449.         if (tag == MKTAG('i', 'd', 'x', '1') &&

  1450.             avi_read_idx1(s, size) >= 0) {

  1451.             ret = 0;

  1452.             break;

  1453.         }

  1454. 

  1455.         size += (size & 1);

  1456.         if (avio_skip(pb, size) < 0)

  1457.             break; // something is wrong here

  1458.     }

  1459. 

  1460. the_end:

  1461.     avio_seek(pb, pos, SEEK_SET);

  1462.     return ret;

  1463. }

  1464. 

  1465. static void seek_subtitle(AVStream *st, AVStream *st2, int64_t timestamp)

  1466. {

  1467.     AVIStream *ast2 = st2->priv_data;

  1468.     int64_t ts2     = av_rescale_q(timestamp, st->time_base, st2->time_base);

  1469.     av_free_packet(&ast2->sub_pkt);

  1470.     if (avformat_seek_file(ast2->sub_ctx, 0, INT64_MIN, ts2, ts2, 0) >= 0 ||

  1471.         avformat_seek_file(ast2->sub_ctx, 0, ts2, ts2, INT64_MAX, 0) >= 0)

  1472.         ff_read_packet(ast2->sub_ctx, &ast2->sub_pkt);

  1473. }

  1474. 

  1475. static int avi_read_seek(AVFormatContext *s, int stream_index,

  1476.                          int64_t timestamp, int flags)

  1477. {

  1478.     AVIContext *avi = s->priv_data;

  1479.     AVStream *st;

  1480.     int i, index;

  1481.     int64_t pos;

  1482.     AVIStream *ast;

  1483. 

  1484.     /* Does not matter which stream is requested dv in avi has the

  1485.      * stream information in the first video stream.

  1486.      */

  1487.     if (avi->dv_demux)

  1488.         stream_index = 0;

  1489. 

  1490.     if (!avi->index_loaded) {

  1491.         /* we only load the index on demand */

  1492.         avi_load_index(s);

  1493.         avi->index_loaded = 1;

  1494.     }

  1495. 

  1496.     st    = s->streams[stream_index];

  1497.     ast   = st->priv_data;

  1498.     index = av_index_search_timestamp(st,

  1499.                                       timestamp * FFMAX(ast->sample_size, 1),

  1500.                                       flags);

  1501.     if (index < 0)

  1502.         return AVERROR_INVALIDDATA;

  1503. 

  1504.     /* find the position */

  1505.     pos       = st->index_entries[index].pos;

  1506.     timestamp = st->index_entries[index].timestamp / FFMAX(ast->sample_size, 1);

  1507. 

  1508.     av_dlog(s, "XX %"PRId64" %d %"PRId64"\n",

  1509.             timestamp, index, st->index_entries[index].timestamp);

  1510. 

  1511.     if (CONFIG_DV_DEMUXER && avi->dv_demux) {

  1512.         /* One and only one real stream for DV in AVI, and it has video  */

  1513.         /* offsets. Calling with other stream indexes should have failed */

  1514.         /* the av_index_search_timestamp call above.                     */

  1515. 

  1516.         /* Feed the DV video stream version of the timestamp to the */

  1517.         /* DV demux so it can synthesize correct timestamps.        */

  1518.         ff_dv_offset_reset(avi->dv_demux, timestamp);

  1519. 

  1520.         avio_seek(s->pb, pos, SEEK_SET);

  1521.         avi->stream_index = -1;

  1522.         return 0;

  1523.     }

  1524. 

  1525.     for (i = 0; i < s->nb_streams; i++) {

  1526.         AVStream *st2   = s->streams[i];

  1527.         AVIStream *ast2 = st2->priv_data;

  1528. 

  1529.         ast2->packet_size =

  1530.         ast2->remaining   = 0;

  1531. 

  1532.         if (ast2->sub_ctx) {

  1533.             seek_subtitle(st, st2, timestamp);

  1534.             continue;

  1535.         }

  1536. 

  1537.         if (st2->nb_index_entries <= 0)

  1538.             continue;

  1539. 

  1540. //        assert(st2->codec->block_align);

  1541.         assert((int64_t)st2->time_base.num * ast2->rate ==

  1542.                (int64_t)st2->time_base.den * ast2->scale);

  1543.         index = av_index_search_timestamp(st2,

  1544.                                           av_rescale_q(timestamp,

  1545.                                                        st->time_base,

  1546.                                                        st2->time_base) *

  1547.                                           FFMAX(ast2->sample_size, 1),

  1548.                                           flags | AVSEEK_FLAG_BACKWARD);

  1549.         if (index < 0)

  1550.             index = 0;

  1551. 

  1552.         if (!avi->non_interleaved) {

  1553.             while (index > 0 && st2->index_entries[index].pos > pos)

  1554.                 index--;

  1555.             while (index + 1 < st2->nb_index_entries &&

  1556.                    st2->index_entries[index].pos < pos)

  1557.                 index++;

  1558.         }

  1559. 

  1560.         av_dlog(s, "%"PRId64" %d %"PRId64"\n",

  1561.                 timestamp, index, st2->index_entries[index].timestamp);

  1562.         /* extract the current frame number */

  1563.         ast2->frame_offset = st2->index_entries[index].timestamp;

  1564.     }

  1565. 

  1566.     /* do the seek */

  1567.     avio_seek(s->pb, pos, SEEK_SET);

  1568.     avi->stream_index = -1;

  1569.     return 0;

  1570. }

  1571. 

  1572. static int avi_read_close(AVFormatContext *s)

  1573. {

  1574.     int i;

  1575.     AVIContext *avi = s->priv_data;

  1576. 

  1577.     for (i = 0; i < s->nb_streams; i++) {

  1578.         AVStream *st   = s->streams[i];

  1579.         AVIStream *ast = st->priv_data;

  1580.         if (ast) {

  1581.             if (ast->sub_ctx) {

  1582.                 av_freep(&ast->sub_ctx->pb);

  1583.                 avformat_close_input(&ast->sub_ctx);

  1584.             }

  1585.             av_free(ast->sub_buffer);

  1586.             av_free_packet(&ast->sub_pkt);

  1587.         }

  1588.     }

  1589. 

  1590.     av_free(avi->dv_demux);

  1591. 

  1592.     return 0;

  1593. }

  1594. 

  1595. static int avi_probe(AVProbeData *p)

  1596. {

  1597.     int i;

  1598. 

  1599.     /* check file header */

  1600.     for (i = 0; avi_headers[i][0]; i++)

  1601.         if (!memcmp(p->buf,     avi_headers[i],     4) &&

  1602.             !memcmp(p->buf + 8, avi_headers[i] + 4, 4))

  1603.             return AVPROBE_SCORE_MAX;

  1604. 

  1605.     return 0;

  1606. }

  1607. 

  1608. AVInputFormat ff_avi_demuxer = {

  1609.     .name           = "avi",

  1610.     .long_name      = NULL_IF_CONFIG_SMALL("AVI (Audio Video Interleaved)"),

  1611.     .priv_data_size = sizeof(AVIContext),

  1612.     .extensions     = "avi",

  1613.     .read_probe     = avi_probe,

  1614.     .read_header    = avi_read_header,

  1615.     .read_packet    = avi_read_packet,

  1616.     .read_close     = avi_read_close,

  1617.     .read_seek      = avi_read_seek,

  1618. };