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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 FFmpeg.

  6.  *

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

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

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

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

  11.  *

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

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

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

  15.  * Lesser General Public License for more details.

  16.  *

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

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

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

  20.  */

  21. 

  22. #include "libavutil/intreadwrite.h"

  23. #include "libavutil/mathematics.h"

  24. #include "libavutil/bswap.h"

  25. #include "libavutil/opt.h"

  26. #include "libavutil/dict.h"

  27. #include "libavutil/avstring.h"

  28. #include "libavutil/avassert.h"

  29. #include "avformat.h"

  30. #include "internal.h"

  31. #include "avi.h"

  32. #include "dv.h"

  33. #include "riff.h"

  34. 

  35. typedef struct AVIStream {

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

  37.                          (used to compute the pts) */

  38.     int remaining;

  39.     int packet_size;

  40. 

  41.     uint32_t scale;

  42.     uint32_t rate;

  43.     int sample_size; /* size of one sample (or packet) (in the rate/scale sense) in bytes */

  44. 

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

  46. 

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

  48.     int prefix_count;

  49.     uint32_t pal[256];

  50.     int has_pal;

  51.     int dshow_block_align;            ///< block align variable used to emulate bugs in the MS dshow demuxer

  52. 

  53.     AVFormatContext *sub_ctx;

  54.     AVPacket sub_pkt;

  55.     uint8_t *sub_buffer;

  56. 

  57.     int64_t seek_pos;

  58. } AVIStream;

  59. 

  60. typedef struct {

  61.     const AVClass *class;

  62.     int64_t  riff_end;

  63.     int64_t  movi_end;

  64.     int64_t  fsize;

  65.     int64_t io_fsize;

  66.     int64_t movi_list;

  67.     int64_t last_pkt_pos;

  68.     int index_loaded;

  69.     int is_odml;

  70.     int non_interleaved;

  71.     int stream_index;

  72.     DVDemuxContext* dv_demux;

  73.     int odml_depth;

  74.     int use_odml;

  75. #define MAX_ODML_DEPTH 1000

  76.     int64_t dts_max;

  77. } AVIContext;

  78. 

  79. 

  80. static const AVOption options[] = {

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

  82.     { NULL },

  83. };

  84. 

  85. static const AVClass demuxer_class = {

  86.     .class_name = "avi",

  87.     .item_name  = av_default_item_name,

  88.     .option     = options,

  89.     .version    = LIBAVUTIL_VERSION_INT,

  90.     .category   = AV_CLASS_CATEGORY_DEMUXER,

  91. };

  92. 

  93. 

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

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

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

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

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

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

  100.     { 0 }

  101. };

  102. 

  103. static const AVMetadataConv avi_metadata_conv[] = {

  104.     { "strn", "title" },

  105.     { 0 },

  106. };

  107. 

  108. static int avi_load_index(AVFormatContext *s);

  109. static int guess_ni_flag(AVFormatContext *s);

  110. 

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

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

  113.            str, tag & 0xff,                             \

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

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

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

  117.            size)

  118. 

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

  120.     if(ast->sample_size){

  121.         return len;

  122.     }else if (ast->dshow_block_align){

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

  124.     }else

  125.         return 1;

  126. }

  127. 

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

  129. {

  130.     AVIContext *avi = s->priv_data;

  131.     char header[8];

  132.     int i;

  133. 

  134.     /* check RIFF header */

  135.     avio_read(pb, header, 4);

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

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

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

  139. 

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

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

  142.             break;

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

  144.         return AVERROR_INVALIDDATA;

  145. 

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

  147.         av_log(s, AV_LOG_INFO, "This file has been generated by a totally broken muxer.\n");

  148. 

  149.     return 0;

  150. }

  151. 

  152. static int read_braindead_odml_indx(AVFormatContext *s, int frame_num){

  153.     AVIContext *avi = s->priv_data;

  154.     AVIOContext *pb = s->pb;

  155.     int longs_pre_entry= avio_rl16(pb);

  156.     int index_sub_type = avio_r8(pb);

  157.     int index_type     = avio_r8(pb);

  158.     int entries_in_use = avio_rl32(pb);

  159.     int chunk_id       = avio_rl32(pb);

  160.     int64_t base       = avio_rl64(pb);

  161.     int stream_id= 10*((chunk_id&0xFF) - '0') + (((chunk_id>>8)&0xFF) - '0');

  162.     AVStream *st;

  163.     AVIStream *ast;

  164.     int i;

  165.     int64_t last_pos= -1;

  166.     int64_t filesize= avi->fsize;

  167. 

  168.     av_dlog(s, "longs_pre_entry:%d index_type:%d entries_in_use:%d chunk_id:%X base:%16"PRIX64"\n",

  169.             longs_pre_entry,index_type, entries_in_use, chunk_id, base);

  170. 

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

  172.         return AVERROR_INVALIDDATA;

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

  174.     ast = st->priv_data;

  175. 

  176.     if(index_sub_type)

  177.         return AVERROR_INVALIDDATA;

  178. 

  179.     avio_rl32(pb);

  180. 

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

  182.         return AVERROR_INVALIDDATA;

  183.     if(index_type>1)

  184.         return AVERROR_INVALIDDATA;

  185. 

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

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

  188.         if(base>>32 == (base & 0xFFFFFFFF) && (base & 0xFFFFFFFF) < filesize && filesize <= 0xFFFFFFFF)

  189.             base &= 0xFFFFFFFF;

  190.         else

  191.             return AVERROR_INVALIDDATA;

  192.     }

  193. 

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

  195.         if(index_type){

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

  197.             int len    = avio_rl32(pb);

  198.             int key= len >= 0;

  199.             len &= 0x7FFFFFFF;

  200. 

  201. #ifdef DEBUG_SEEK

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

  203. #endif

  204.             if(url_feof(pb))

  205.                 return AVERROR_INVALIDDATA;

  206. 

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

  208.                 avi->non_interleaved= 1;

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

  210.                 av_add_index_entry(st, pos, ast->cum_len, len, 0, key ? AVINDEX_KEYFRAME : 0);

  211. 

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

  213.             last_pos= pos;

  214.         }else{

  215.             int64_t offset, pos;

  216.             int duration;

  217.             offset = avio_rl64(pb);

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

  219.             duration = avio_rl32(pb);

  220. 

  221.             if(url_feof(pb))

  222.                 return AVERROR_INVALIDDATA;

  223. 

  224.             pos = avio_tell(pb);

  225. 

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

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

  228.                 return AVERROR_INVALIDDATA;

  229.             }

  230. 

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

  232.                 return -1;

  233.             avi->odml_depth++;

  234.             read_braindead_odml_indx(s, frame_num);

  235.             avi->odml_depth--;

  236.             frame_num += duration;

  237. 

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

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

  240.                 return -1;

  241.             }

  242. 

  243.         }

  244.     }

  245.     avi->index_loaded=2;

  246.     return 0;

  247. }

  248. 

  249. static void clean_index(AVFormatContext *s){

  250.     int i;

  251.     int64_t j;

  252. 

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

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

  255.         AVIStream *ast = st->priv_data;

  256.         int n= st->nb_index_entries;

  257.         int max= ast->sample_size;

  258.         int64_t pos, size, ts;

  259. 

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

  261.             continue;

  262. 

  263.         while(max < 1024) max+=max;

  264. 

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

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

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

  268. 

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

  270.             av_add_index_entry(st, pos+j, ts+j, FFMIN(max, size-j), 0, AVINDEX_KEYFRAME);

  271.         }

  272.     }

  273. }

  274. 

  275. static int avi_read_tag(AVFormatContext *s, AVStream *st, uint32_t tag, uint32_t size)

  276. {

  277.     AVIOContext *pb = s->pb;

  278.     char key[5] = {0}, *value;

  279. 

  280.     size += (size & 1);

  281. 

  282.     if (size == UINT_MAX)

  283.         return AVERROR(EINVAL);

  284.     value = av_malloc(size+1);

  285.     if (!value)

  286.         return AVERROR(ENOMEM);

  287.     avio_read(pb, value, size);

  288.     value[size]=0;

  289. 

  290.     AV_WL32(key, tag);

  291. 

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

  293.                             AV_DICT_DONT_STRDUP_VAL);

  294. }

  295. 

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

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

  298. 

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

  300. {

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

  302.     int i, day, year;

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

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

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

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

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

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

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

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

  311.             }

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

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

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

  315.     }

  316. }

  317. 

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

  319. {

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

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

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

  323.         switch (tag) {

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

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

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

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

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

  329.                 const char *name = NULL;

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

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

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

  333.                 switch (tag) {

  334.                 case 0x03:  name = "maker";  break;

  335.                 case 0x04:  name = "model";  break;

  336.                 case 0x13:  name = "creation_time";

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

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

  339.                     break;

  340.                 }

  341.                 if (name)

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

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

  344.             }

  345.             break;

  346.         }

  347.         default:

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

  349.             break;

  350.         }

  351.     }

  352. }

  353. 

  354. static int avi_read_header(AVFormatContext *s)

  355. {

  356.     AVIContext *avi = s->priv_data;

  357.     AVIOContext *pb = s->pb;

  358.     unsigned int tag, tag1, handler;

  359.     int codec_type, stream_index, frame_period;

  360.     unsigned int size;

  361.     int i;

  362.     AVStream *st;

  363.     AVIStream *ast = NULL;

  364.     int avih_width=0, avih_height=0;

  365.     int amv_file_format=0;

  366.     uint64_t list_end = 0;

  367.     int ret;

  368.     AVDictionaryEntry *dict_entry;

  369. 

  370.     avi->stream_index= -1;

  371. 

  372.     ret = get_riff(s, pb);

  373.     if (ret < 0)

  374.         return ret;

  375. 

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

  377. 

  378.     avi->io_fsize = 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 (url_feof(pb))

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

  405.                 else     avi->movi_end = avi->fsize;

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

  407.                 goto end_of_header;

  408.             }

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

  410.                 ff_read_riff_info(s, size - 4);

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

  412.                 avi_read_nikon(s, list_end);

  413. 

  414.             break;

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

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

  417.             size += (size & 1);

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

  419.             avio_skip(pb, size);

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

  421.             break;

  422.         }

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

  424.             avi->is_odml = 1;

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

  426.             break;

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

  428.             amv_file_format=1;

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

  430.             /* AVI header */

  431.             /* using frame_period is bad idea */

  432.             frame_period = avio_rl32(pb);

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

  434.             avio_rl32(pb);

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

  436. 

  437.             avio_skip(pb, 2 * 4);

  438.             avio_rl32(pb);

  439.             avio_rl32(pb);

  440.             avih_width=avio_rl32(pb);

  441.             avih_height=avio_rl32(pb);

  442. 

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

  444.             break;

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

  446.             /* stream header */

  447. 

  448.             tag1 = avio_rl32(pb);

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

  450. 

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

  452.                 avio_skip(pb, size - 8);

  453.                 break;

  454.             }else{

  455.                 stream_index++;

  456.                 st = avformat_new_stream(s, NULL);

  457.                 if (!st)

  458.                     goto fail;

  459. 

  460.                 st->id = stream_index;

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

  462.                 if (!ast)

  463.                     goto fail;

  464.                 st->priv_data = ast;

  465.             }

  466.             if(amv_file_format)

  467.                 tag1 = stream_index ? MKTAG('a','u','d','s') : MKTAG('v','i','d','s');

  468. 

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

  470. 

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

  472.                 int64_t dv_dur;

  473. 

  474.                 /*

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

  476.                  * have to support anything but DV in type1 AVIs.

  477.                  */

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

  479.                     goto fail;

  480. 

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

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

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

  484.                    goto fail;

  485. 

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

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

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

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

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

  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.                 }

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

  500.                 avio_skip(pb, 3 * 4);

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

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

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

  504. 

  505.                 dv_dur = avio_rl32(pb);

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

  507.                     dv_dur *= AV_TIME_BASE;

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

  509.                 }

  510.                 /*

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

  512.                  *      will make a guess based on bitrate.

  513.                  */

  514. 

  515.                 stream_index = s->nb_streams - 1;

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

  517.                 break;

  518.             }

  519. 

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

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

  522. 

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

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

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

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

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

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

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

  530.                 av_log(s, AV_LOG_WARNING, "scale/rate is %u/%u which is invalid. (This file has been generated by broken software.)\n", ast->scale, ast->rate);

  531.                 if(frame_period){

  532.                     ast->rate = 1000000;

  533.                     ast->scale = frame_period;

  534.                 }else{

  535.                     ast->rate = 25;

  536.                     ast->scale = 1;

  537.                 }

  538.             }

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

  540. 

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

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

  543. 

  544.             st->start_time = 0;

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

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

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

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

  549.                 return AVERROR_INVALIDDATA;

  550.             }

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

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

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

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

  555. 

  556.             switch(tag1) {

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

  558.                 codec_type = AVMEDIA_TYPE_VIDEO;

  559. 

  560.                 ast->sample_size = 0;

  561.                 break;

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

  563.                 codec_type = AVMEDIA_TYPE_AUDIO;

  564.                 break;

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

  566.                 codec_type = AVMEDIA_TYPE_SUBTITLE;

  567.                 break;

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

  569.                 codec_type = AVMEDIA_TYPE_DATA;

  570.                 break;

  571.             default:

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

  573.             }

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

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

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

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

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

  579.                 }

  580.             }

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

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

  583.             break;

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

  585.             /* stream header */

  586.             if (!size)

  587.                 break;

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

  589.                 avio_skip(pb, size);

  590.             } else {

  591.                 uint64_t cur_pos = avio_tell(pb);

  592.                 unsigned esize;

  593.                 if (cur_pos < list_end)

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

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

  596.                 switch(codec_type) {

  597.                 case AVMEDIA_TYPE_VIDEO:

  598.                     if(amv_file_format){

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

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

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

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

  603.                         avio_skip(pb, size);

  604.                         break;

  605.                     }

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

  607. 

  608.                     if (tag1 == MKTAG('D', 'X', 'S', 'B') || tag1 == MKTAG('D','X','S','A')) {

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

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

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

  612.                         break;

  613.                     }

  614. 

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

  616.                         if(esize == size-1 && (esize&1)) st->codec->extradata_size= esize - 10*4;

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

  618.                         st->codec->extradata= av_malloc(st->codec->extradata_size + FF_INPUT_BUFFER_PADDING_SIZE);

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

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

  621.                             return AVERROR(ENOMEM);

  622.                         }

  623.                         avio_read(pb, st->codec->extradata, st->codec->extradata_size);

  624.                     }

  625. 

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

  627.                         avio_r8(pb);

  628. 

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

  630.                     /* This code assumes that extradata contains only palette. */

  631.                     /* This is true for all paletted codecs implemented in FFmpeg. */

  632.                     if (st->codec->extradata_size && (st->codec->bits_per_coded_sample <= 8)) {

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

  634.                         const uint8_t *pal_src;

  635. 

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

  637.                         pal_src = st->codec->extradata + st->codec->extradata_size - pal_size;

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

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

  640.                         ast->has_pal = 1;

  641.                     }

  642. 

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

  644. 

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

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

  647.                     st->codec->codec_id = ff_codec_get_id(ff_codec_bmp_tags, tag1);

  648.                     st->need_parsing = AVSTREAM_PARSE_HEADERS; // This is needed to get the pict type which is necessary for generating correct pts.

  649. 

  650.                     if(st->codec->codec_tag==0 && st->codec->height > 0 && st->codec->extradata_size < 1U<<30){

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

  652.                         st->codec->extradata= av_realloc_f(st->codec->extradata, 1, st->codec->extradata_size + FF_INPUT_BUFFER_PADDING_SIZE);

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

  654.                             memcpy(st->codec->extradata + st->codec->extradata_size - 9, "BottomUp", 9);

  655.                     }

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

  657. 

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

  659.                     break;

  660.                 case AVMEDIA_TYPE_AUDIO:

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

  662.                     if (ret < 0)

  663.                         return ret;

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

  665.                     if(ast->sample_size && st->codec->block_align && ast->sample_size != st->codec->block_align){

  666.                         av_log(s, AV_LOG_WARNING, "sample size (%d) != block align (%d)\n", ast->sample_size, st->codec->block_align);

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

  668.                     }

  669.                     if (size&1) /* 2-aligned (fix for Stargate SG-1 - 3x18 - Shades of Grey.avi) */

  670.                         avio_skip(pb, 1);

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

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

  673.                     st->need_parsing = AVSTREAM_PARSE_TIMESTAMPS;

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

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

  676.                      * fail. */

  677.                     if (st->codec->codec_id == AV_CODEC_ID_AAC && st->codec->extradata_size)

  678.                         st->need_parsing = AVSTREAM_PARSE_NONE;

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

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

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

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

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

  684.                         ast->dshow_block_align = 0;

  685.                     }

  686.                     if (amv_file_format){

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

  688.                         ast->dshow_block_align = 0;

  689.                     }

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

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

  692.                         ast->dshow_block_align = 0;

  693.                     }

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

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

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

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

  698.                         ast->sample_size = 0;

  699.                     }

  700.                     break;

  701.                 case AVMEDIA_TYPE_SUBTITLE:

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

  703.                     st->request_probe= 1;

  704.                     avio_skip(pb, size);

  705.                     break;

  706.                 default:

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

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

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

  710.                     avio_skip(pb, size);

  711.                     break;

  712.                 }

  713.             }

  714.             break;

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

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

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

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

  719.                 avio_skip(pb, size);

  720.             } else {

  721.                 uint64_t cur_pos = avio_tell(pb);

  722.                 if (cur_pos < list_end)

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

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

  725. 

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

  727.                     st->codec->extradata_size= size;

  728.                     st->codec->extradata= av_mallocz(st->codec->extradata_size + FF_INPUT_BUFFER_PADDING_SIZE);

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

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

  731.                         return AVERROR(ENOMEM);

  732.                     }

  733.                     avio_read(pb, st->codec->extradata, st->codec->extradata_size);

  734.                 }

  735. 

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

  737.                     avio_r8(pb);

  738.             }

  739.             break;

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

  741.             i= avio_tell(pb);

  742.             if(pb->seekable && !(s->flags & AVFMT_FLAG_IGNIDX) && avi->use_odml &&

  743.                read_braindead_odml_indx(s, 0) < 0 && (s->error_recognition & AV_EF_EXPLODE))

  744.                 goto fail;

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

  746.             break;

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

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

  749.                 AVRational active, active_aspect;

  750. 

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

  752.                 avio_rl32(pb);

  753.                 avio_rl32(pb);

  754.                 avio_rl32(pb);

  755.                 avio_rl32(pb);

  756.                 avio_rl32(pb);

  757. 

  758.                 active_aspect.den= avio_rl16(pb);

  759.                 active_aspect.num= avio_rl16(pb);

  760.                 active.num       = avio_rl32(pb);

  761.                 active.den       = avio_rl32(pb);

  762.                 avio_rl32(pb); //nbFieldsPerFrame

  763. 

  764.                 if(active_aspect.num && active_aspect.den && active.num && active.den){

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

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

  767.                             active_aspect.num, active_aspect.den,

  768.                             active.num, active.den);

  769.                 }

  770.                 size -= 9*4;

  771.             }

  772.             avio_skip(pb, size);

  773.             break;

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

  775.             if(s->nb_streams){

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

  777.                 if (ret < 0)

  778.                     return ret;

  779.                 break;

  780.             }

  781.         default:

  782.             if(size > 1000000){

  783.                 av_log(s, AV_LOG_ERROR, "Something went wrong during header parsing, "

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

  785.                 if (s->error_recognition & AV_EF_EXPLODE)

  786.                     goto fail;

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

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

  789.                 goto end_of_header;

  790.             }

  791.             /* skip tag */

  792.             size += (size & 1);

  793.             avio_skip(pb, size);

  794.             break;

  795.         }

  796.     }

  797.  end_of_header:

  798.     /* check stream number */

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

  800.     fail:

  801.         return AVERROR_INVALIDDATA;

  802.     }

  803. 

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

  805.         avi_load_index(s);

  806.     avi->index_loaded |= 1;

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

  808. 

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

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

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

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

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

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

  815.                 st->need_parsing = AVSTREAM_PARSE_FULL;

  816.         }

  817. 

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

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

  820.         if(st->nb_index_entries)

  821.             break;

  822.     }

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

  824.     // a mis-detection.

  825.     if(avi->dv_demux)

  826.         avi->non_interleaved=0;

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

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

  845.         uint8_t desc[256];

  846.         int score = AVPROBE_SCORE_EXTENSION, ret;

  847.         AVIStream *ast = st->priv_data;

  848.         AVInputFormat *sub_demuxer;

  849.         AVRational time_base;

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

  851.                                               pkt->size - 7,

  852.                                               0, NULL, NULL, NULL, NULL);

  853.         AVProbeData pd;

  854.         unsigned int desc_len = avio_rl32(pb);

  855. 

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

  857.             goto error;

  858. 

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

  860.         avio_skip(pb, desc_len - ret);

  861.         if (*desc)

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

  863. 

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

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

  866. 

  867.         pd = (AVProbeData) { .buf = pb->buf_ptr, .buf_size = pb->buf_end - pb->buf_ptr };

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

  869.             goto error;

  870. 

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

  872.             goto error;

  873. 

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

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

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

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

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

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

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

  881.         }

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

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

  884.         return 1;

  885. error:

  886.         av_freep(&pb);

  887.     }

  888.     return 0;

  889. }

  890. 

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

  892.                                   AVPacket *pkt)

  893. {

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

  895.     int64_t ts, next_ts, ts_min = INT64_MAX;

  896.     AVStream *st, *sub_st = NULL;

  897.     int i;

  898. 

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

  900.                            AV_TIME_BASE_Q);

  901. 

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

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

  904.         ast = st->priv_data;

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

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

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

  908.                 ts_min = ts;

  909.                 sub_st = st;

  910.             }

  911.         }

  912.     }

  913. 

  914.     if (sub_st) {

  915.         ast = sub_st->priv_data;

  916.         *pkt = ast->sub_pkt;

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

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

  919.             ast->sub_pkt.data = NULL;

  920.     }

  921.     return sub_st;

  922. }

  923. 

  924. static int get_stream_idx(int *d){

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

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

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

  928.     }else{

  929.         return 100; //invalid stream ID

  930.     }

  931. }

  932. 

  933. /**

  934.  *

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

  936.  */

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

  938. {

  939.     AVIContext *avi = s->priv_data;

  940.     AVIOContext *pb = s->pb;

  941.     int n;

  942.     unsigned int d[8];

  943.     unsigned int size;

  944.     int64_t i, sync;

  945. 

  946. start_sync:

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

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

  949.         int j;

  950. 

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

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

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

  954. 

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

  956. 

  957.         n= get_stream_idx(d+2);

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

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

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

  961.             continue;

  962. 

  963.         //parse ix##

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

  965.         //parse JUNK

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

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

  968.             avio_skip(pb, size);

  969.             goto start_sync;

  970.         }

  971. 

  972.         //parse stray LIST

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

  974.             avio_skip(pb, 4);

  975.             goto start_sync;

  976.         }

  977. 

  978.         n= get_stream_idx(d);

  979. 

  980.         if(!((i-avi->last_pkt_pos)&1) && get_stream_idx(d+1) < s->nb_streams)

  981.             continue;

  982. 

  983.         //detect ##ix chunk and skip

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

  985.             avio_skip(pb, size);

  986.             goto start_sync;

  987.         }

  988. 

  989.         //parse ##dc/##wb

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

  991.             AVStream *st;

  992.             AVIStream *ast;

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

  994.             ast = st->priv_data;

  995. 

  996.             if (!ast) {

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

  998.                 continue;

  999.             }

  1000. 

  1001.             if(s->nb_streams>=2){

  1002.                 AVStream *st1  = s->streams[1];

  1003.                 AVIStream *ast1= st1->priv_data;

  1004.                 //workaround for broken small-file-bug402.avi

  1005.                 if(   d[2] == 'w' && d[3] == 'b'

  1006.                    && n==0

  1007.                    && st ->codec->codec_type == AVMEDIA_TYPE_VIDEO

  1008.                    && st1->codec->codec_type == AVMEDIA_TYPE_AUDIO

  1009.                    && ast->prefix == 'd'*256+'c'

  1010.                    && (d[2]*256+d[3] == ast1->prefix || !ast1->prefix_count)

  1011.                   ){

  1012.                     n=1;

  1013.                     st = st1;

  1014.                     ast = ast1;

  1015.                     av_log(s, AV_LOG_WARNING, "Invalid stream + prefix combination, assuming audio.\n");

  1016.                 }

  1017.             }

  1018. 

  1019. 

  1020.             if(   (st->discard >= AVDISCARD_DEFAULT && size==0)

  1021.                /*|| (st->discard >= AVDISCARD_NONKEY && !(pkt->flags & AV_PKT_FLAG_KEY))*/ //FIXME needs a little reordering

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

  1023.                 if (!exit_early) {

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

  1025.                     avio_skip(pb, size);

  1026.                     goto start_sync;

  1027.                 }

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

  1037.                     ast->pal[k] = 0xFFU<<24 | avio_rb32(pb)>>8;// b + (g << 8) + (r << 16);

  1038.                 ast->has_pal= 1;

  1039.                 goto start_sync;

  1040.             } else if(   ((ast->prefix_count<5 || sync+9 > i) && d[2]<128 && d[3]<128) ||

  1041.                          d[2]*256+d[3] == ast->prefix /*||

  1042.                          (d[2] == 'd' && d[3] == 'c') ||

  1043.                          (d[2] == 'w' && d[3] == 'b')*/) {

  1044. 

  1045.                 if (exit_early)

  1046.                     return 0;

  1047.                 if(d[2]*256+d[3] == ast->prefix)

  1048.                     ast->prefix_count++;

  1049.                 else{

  1050.                     ast->prefix= d[2]*256+d[3];

  1051.                     ast->prefix_count= 0;

  1052.                 }

  1053. 

  1054.                 avi->stream_index= n;

  1055.                 ast->packet_size= size + 8;

  1056.                 ast->remaining= size;

  1057. 

  1058.                 if(size || !ast->sample_size){

  1059.                     uint64_t pos= avio_tell(pb) - 8;

  1060.                     if(!st->index_entries || !st->nb_index_entries || st->index_entries[st->nb_index_entries - 1].pos < pos){

  1061.                         av_add_index_entry(st, pos, ast->frame_offset, size, 0, AVINDEX_KEYFRAME);

  1062.                     }

  1063.                 }

  1064.                 return 0;

  1065.             }

  1066.         }

  1067.     }

  1068. 

  1069.     if(pb->error)

  1070.         return pb->error;

  1071.     return AVERROR_EOF;

  1072. }

  1073. 

  1074. static int avi_read_packet(AVFormatContext *s, AVPacket *pkt)

  1075. {

  1076.     AVIContext *avi = s->priv_data;

  1077.     AVIOContext *pb = s->pb;

  1078.     int err;

  1079. #if FF_API_DESTRUCT_PACKET

  1080.     void* dstr;

  1081. #endif

  1082. 

  1083.     if (CONFIG_DV_DEMUXER && avi->dv_demux) {

  1084.         int size = avpriv_dv_get_packet(avi->dv_demux, pkt);

  1085.         if (size >= 0)

  1086.             return size;

  1087.     }

  1088. 

  1089.     if(avi->non_interleaved){

  1090.         int best_stream_index = 0;

  1091.         AVStream *best_st= NULL;

  1092.         AVIStream *best_ast;

  1093.         int64_t best_ts= INT64_MAX;

  1094.         int i;

  1095. 

  1096.         for(i=0; i<s->nb_streams; i++){

  1097.             AVStream *st = s->streams[i];

  1098.             AVIStream *ast = st->priv_data;

  1099.             int64_t ts= ast->frame_offset;

  1100.             int64_t last_ts;

  1101. 

  1102.             if(!st->nb_index_entries)

  1103.                 continue;

  1104. 

  1105.             last_ts = st->index_entries[st->nb_index_entries - 1].timestamp;

  1106.             if(!ast->remaining && ts > last_ts)

  1107.                 continue;

  1108. 

  1109.             ts = av_rescale_q(ts, st->time_base, (AVRational){FFMAX(1, ast->sample_size), AV_TIME_BASE});

  1110. 

  1111.             av_dlog(s, "%"PRId64" %d/%d %"PRId64"\n", ts,

  1112.                     st->time_base.num, st->time_base.den, ast->frame_offset);

  1113.             if(ts < best_ts){

  1114.                 best_ts= ts;

  1115.                 best_st= st;

  1116.                 best_stream_index= i;

  1117.             }

  1118.         }

  1119.         if(!best_st)

  1120.             return AVERROR_EOF;

  1121. 

  1122.         best_ast = best_st->priv_data;

  1123.         best_ts = best_ast->frame_offset;

  1124.         if(best_ast->remaining)

  1125.             i= av_index_search_timestamp(best_st, best_ts, AVSEEK_FLAG_ANY | AVSEEK_FLAG_BACKWARD);

  1126.         else{

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

  1128.             if(i>=0)

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

  1130.         }

  1131. 

  1132.         if(i>=0){

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

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

  1135.             if(avio_seek(s->pb, pos + 8, SEEK_SET) < 0)

  1136.               return AVERROR_EOF;

  1137. 

  1138.             av_assert0(best_ast->remaining <= best_ast->packet_size);

  1139. 

  1140.             avi->stream_index= best_stream_index;

  1141.             if(!best_ast->remaining)

  1142.                 best_ast->packet_size=

  1143.                 best_ast->remaining= best_st->index_entries[i].size;

  1144.         }

  1145.         else

  1146.           return AVERROR_EOF;

  1147.     }

  1148. 

  1149. resync:

  1150.     if(avi->stream_index >= 0){

  1151.         AVStream *st= s->streams[ avi->stream_index ];

  1152.         AVIStream *ast= st->priv_data;

  1153.         int size, err;

  1154. 

  1155.         if(get_subtitle_pkt(s, st, pkt))

  1156.             return 0;

  1157. 

  1158.         if(ast->sample_size <= 1) // minorityreport.AVI block_align=1024 sample_size=1 IMA-ADPCM

  1159.             size= INT_MAX;

  1160.         else if(ast->sample_size < 32)

  1161.             // arbitrary multiplier to avoid tiny packets for raw PCM data

  1162.             size= 1024*ast->sample_size;

  1163.         else

  1164.             size= ast->sample_size;

  1165. 

  1166.         if(size > ast->remaining)

  1167.             size= ast->remaining;

  1168.         avi->last_pkt_pos= avio_tell(pb);

  1169.         err= av_get_packet(pb, pkt, size);

  1170.         if(err<0)

  1171.             return err;

  1172.         size = err;

  1173. 

  1174.         if(ast->has_pal && pkt->size<(unsigned)INT_MAX/2){

  1175.             uint8_t *pal;

  1176.             pal = av_packet_new_side_data(pkt, AV_PKT_DATA_PALETTE, AVPALETTE_SIZE);

  1177.             if(!pal){

  1178.                 av_log(s, AV_LOG_ERROR, "Failed to allocate data for palette\n");

  1179.             }else{

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

  1181.                 ast->has_pal = 0;

  1182.             }

  1183.         }

  1184. 

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

  1186.             AVBufferRef *avbuf = pkt->buf;

  1187. #if FF_API_DESTRUCT_PACKET

  1188.             dstr = pkt->destruct;

  1189. #endif

  1190.             size = avpriv_dv_produce_packet(avi->dv_demux, pkt,

  1191.                                     pkt->data, pkt->size, pkt->pos);

  1192. #if FF_API_DESTRUCT_PACKET

  1193.             pkt->destruct = dstr;

  1194. #endif

  1195.             pkt->buf = avbuf;

  1196.             pkt->flags |= AV_PKT_FLAG_KEY;

  1197.             if (size < 0)

  1198.                 av_free_packet(pkt);

  1199.         } else if (st->codec->codec_type == AVMEDIA_TYPE_SUBTITLE

  1200.                    && !st->codec->codec_tag && read_gab2_sub(st, pkt)) {

  1201.             ast->frame_offset++;

  1202.             avi->stream_index = -1;

  1203.             ast->remaining = 0;

  1204.             goto resync;

  1205.         } else {

  1206.             /* XXX: How to handle B-frames in AVI? */

  1207.             pkt->dts = ast->frame_offset;

  1208. //                pkt->dts += ast->start;

  1209.             if(ast->sample_size)

  1210.                 pkt->dts /= ast->sample_size;

  1211.             av_dlog(s, "dts:%"PRId64" offset:%"PRId64" %d/%d smpl_siz:%d base:%d st:%d size:%d\n",

  1212.                     pkt->dts, ast->frame_offset, ast->scale, ast->rate,

  1213.                     ast->sample_size, AV_TIME_BASE, avi->stream_index, size);

  1214.             pkt->stream_index = avi->stream_index;

  1215. 

  1216.             if (st->codec->codec_type == AVMEDIA_TYPE_VIDEO) {

  1217.                 AVIndexEntry *e;

  1218.                 int index;

  1219.                 av_assert0(st->index_entries);

  1220. 

  1221.                 index= av_index_search_timestamp(st, ast->frame_offset, 0);

  1222.                 e= &st->index_entries[index];

  1223. 

  1224.                 if(index >= 0 && e->timestamp == ast->frame_offset){

  1225.                     if (index == st->nb_index_entries-1){

  1226.                         int key=1;

  1227.                         int i;

  1228.                         uint32_t state=-1;

  1229.                         for(i=0; i<FFMIN(size,256); i++){

  1230.                             if(st->codec->codec_id == AV_CODEC_ID_MPEG4){

  1231.                                 if(state == 0x1B6){

  1232.                                     key= !(pkt->data[i]&0xC0);

  1233.                                     break;

  1234.                                 }

  1235.                             }else

  1236.                                 break;

  1237.                             state= (state<<8) + pkt->data[i];

  1238.                         }

  1239.                         if(!key)

  1240.                             e->flags &= ~AVINDEX_KEYFRAME;

  1241.                     }

  1242.                     if (e->flags & AVINDEX_KEYFRAME)

  1243.                         pkt->flags |= AV_PKT_FLAG_KEY;

  1244.                 }

  1245.             } else {

  1246.                 pkt->flags |= AV_PKT_FLAG_KEY;

  1247.             }

  1248.             ast->frame_offset += get_duration(ast, pkt->size);

  1249.         }

  1250.         ast->remaining -= err;

  1251.         if(!ast->remaining){

  1252.             avi->stream_index= -1;

  1253.             ast->packet_size= 0;

  1254.         }

  1255. 

  1256.         if(!avi->non_interleaved && pkt->pos >= 0 && ast->seek_pos > pkt->pos){

  1257.             av_free_packet(pkt);

  1258.             goto resync;

  1259.         }

  1260.         ast->seek_pos= 0;

  1261. 

  1262.         if(!avi->non_interleaved && st->nb_index_entries>1 && avi->index_loaded>1){

  1263.             int64_t dts= av_rescale_q(pkt->dts, st->time_base, AV_TIME_BASE_Q);

  1264. 

  1265.             if(avi->dts_max - dts > 2*AV_TIME_BASE){

  1266.                 avi->non_interleaved= 1;

  1267.                 av_log(s, AV_LOG_INFO, "Switching to NI mode, due to poor interleaving\n");

  1268.             }else if(avi->dts_max < dts)

  1269.                 avi->dts_max = dts;

  1270.         }

  1271. 

  1272.         return 0;

  1273.     }

  1274. 

  1275.     if ((err = avi_sync(s, 0)) < 0)

  1276.         return err;

  1277.     goto resync;

  1278. }

  1279. 

  1280. /* XXX: We make the implicit supposition that the positions are sorted

  1281.    for each stream. */

  1282. static int avi_read_idx1(AVFormatContext *s, int size)

  1283. {

  1284.     AVIContext *avi = s->priv_data;

  1285.     AVIOContext *pb = s->pb;

  1286.     int nb_index_entries, i;

  1287.     AVStream *st;

  1288.     AVIStream *ast;

  1289.     unsigned int index, tag, flags, pos, len, first_packet = 1;

  1290.     unsigned last_pos= -1;

  1291.     unsigned last_idx= -1;

  1292.     int64_t idx1_pos, first_packet_pos = 0, data_offset = 0;

  1293.     int anykey = 0;

  1294. 

  1295.     nb_index_entries = size / 16;

  1296.     if (nb_index_entries <= 0)

  1297.         return AVERROR_INVALIDDATA;

  1298. 

  1299.     idx1_pos = avio_tell(pb);

  1300.     avio_seek(pb, avi->movi_list+4, SEEK_SET);

  1301.     if (avi_sync(s, 1) == 0) {

  1302.         first_packet_pos = avio_tell(pb) - 8;

  1303.     }

  1304.     avi->stream_index = -1;

  1305.     avio_seek(pb, idx1_pos, SEEK_SET);

  1306. 

  1307.     if (s->nb_streams == 1 && s->streams[0]->codec->codec_tag == AV_RL32("MMES")){

  1308.         first_packet_pos = 0;

  1309.         data_offset = avi->movi_list;

  1310.     }

  1311. 

  1312.     /* Read the entries and sort them in each stream component. */

  1313.     for(i = 0; i < nb_index_entries; i++) {

  1314.         if(url_feof(pb))

  1315.             return -1;

  1316. 

  1317.         tag = avio_rl32(pb);

  1318.         flags = avio_rl32(pb);

  1319.         pos = avio_rl32(pb);

  1320.         len = avio_rl32(pb);

  1321.         av_dlog(s, "%d: tag=0x%x flags=0x%x pos=0x%x len=%d/",

  1322.                 i, tag, flags, pos, len);

  1323. 

  1324.         index = ((tag & 0xff) - '0') * 10;

  1325.         index += ((tag >> 8) & 0xff) - '0';

  1326.         if (index >= s->nb_streams)

  1327.             continue;

  1328.         st = s->streams[index];

  1329.         ast = st->priv_data;

  1330. 

  1331.         if(first_packet && first_packet_pos && len) {

  1332.             data_offset = first_packet_pos - pos;

  1333.             first_packet = 0;

  1334.         }

  1335.         pos += data_offset;

  1336. 

  1337.         av_dlog(s, "%d cum_len=%"PRId64"\n", len, ast->cum_len);

  1338. 

  1339.         // even if we have only a single stream, we should

  1340.         // switch to non-interleaved to get correct timestamps

  1341.         if(last_pos == pos)

  1342.             avi->non_interleaved= 1;

  1343.         if(last_idx != pos && len) {

  1344.             av_add_index_entry(st, pos, ast->cum_len, len, 0, (flags&AVIIF_INDEX) ? AVINDEX_KEYFRAME : 0);

  1345.             last_idx= pos;

  1346.         }

  1347.         ast->cum_len += get_duration(ast, len);

  1348.         last_pos= pos;

  1349.         anykey |= flags&AVIIF_INDEX;

  1350.     }

  1351.     if (!anykey) {

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

  1353.             st = s->streams[index];

  1354.             if (st->nb_index_entries)

  1355.                 st->index_entries[0].flags |= AVINDEX_KEYFRAME;

  1356.         }

  1357.     }

  1358.     return 0;

  1359. }

  1360. 

  1361. static int guess_ni_flag(AVFormatContext *s){

  1362.     int i;

  1363.     int64_t last_start=0;

  1364.     int64_t first_end= INT64_MAX;

  1365.     int64_t oldpos= avio_tell(s->pb);

  1366.     int *idx;

  1367.     int64_t min_pos, pos;

  1368. 

  1369.     for(i=0; i<s->nb_streams; i++){

  1370.         AVStream *st = s->streams[i];

  1371.         int n= st->nb_index_entries;

  1372.         unsigned int size;

  1373. 

  1374.         if(n <= 0)

  1375.             continue;

  1376. 

  1377.         if(n >= 2){

  1378.             int64_t pos= st->index_entries[0].pos;

  1379.             avio_seek(s->pb, pos + 4, SEEK_SET);

  1380.             size= avio_rl32(s->pb);

  1381.             if(pos + size > st->index_entries[1].pos)

  1382.                 last_start= INT64_MAX;

  1383.         }

  1384. 

  1385.         if(st->index_entries[0].pos > last_start)

  1386.             last_start= st->index_entries[0].pos;

  1387.         if(st->index_entries[n-1].pos < first_end)

  1388.             first_end= st->index_entries[n-1].pos;

  1389.     }

  1390.     avio_seek(s->pb, oldpos, SEEK_SET);

  1391.     if (last_start > first_end)

  1392.         return 1;

  1393.     idx= av_mallocz(sizeof(*idx) * s->nb_streams);

  1394.     for (min_pos=pos=0; min_pos!=INT64_MAX; pos= min_pos+1LU) {

  1395.         int64_t max_dts = INT64_MIN/2, min_dts= INT64_MAX/2;

  1396.         min_pos = INT64_MAX;

  1397. 

  1398.         for (i=0; i<s->nb_streams; i++) {

  1399.             AVStream *st = s->streams[i];

  1400.             AVIStream *ast = st->priv_data;

  1401.             int n= st->nb_index_entries;

  1402.             while (idx[i]<n && st->index_entries[idx[i]].pos < pos)

  1403.                 idx[i]++;

  1404.             if (idx[i] < n) {

  1405.                 min_dts = FFMIN(min_dts, av_rescale_q(st->index_entries[idx[i]].timestamp/FFMAX(ast->sample_size, 1), st->time_base, AV_TIME_BASE_Q));

  1406.                 min_pos = FFMIN(min_pos, st->index_entries[idx[i]].pos);

  1407.             }

  1408.             if (idx[i])

  1409.                 max_dts = FFMAX(max_dts, av_rescale_q(st->index_entries[idx[i]-1].timestamp/FFMAX(ast->sample_size, 1), st->time_base, AV_TIME_BASE_Q));

  1410.         }

  1411.         if(max_dts - min_dts > 2*AV_TIME_BASE) {

  1412.             av_free(idx);

  1413.             return 1;

  1414.         }

  1415.     }

  1416.     av_free(idx);

  1417.     return 0;

  1418. }

  1419. 

  1420. static int avi_load_index(AVFormatContext *s)

  1421. {

  1422.     AVIContext *avi = s->priv_data;

  1423.     AVIOContext *pb = s->pb;

  1424.     uint32_t tag, size;

  1425.     int64_t pos= avio_tell(pb);

  1426.     int64_t next;

  1427.     int ret = -1;

  1428. 

  1429.     if (avio_seek(pb, avi->movi_end, SEEK_SET) < 0)

  1430.         goto the_end; // maybe truncated file

  1431.     av_dlog(s, "movi_end=0x%"PRIx64"\n", avi->movi_end);

  1432.     for(;;) {

  1433.         tag = avio_rl32(pb);

  1434.         size = avio_rl32(pb);

  1435.         if (url_feof(pb))

  1436.             break;

  1437.         next = avio_tell(pb) + size + (size & 1);

  1438. 

  1439.         av_dlog(s, "tag=%c%c%c%c size=0x%x\n",

  1440.                  tag        & 0xff,

  1441.                 (tag >>  8) & 0xff,

  1442.                 (tag >> 16) & 0xff,

  1443.                 (tag >> 24) & 0xff,

  1444.                 size);

  1445. 

  1446.         if (tag == MKTAG('i', 'd', 'x', '1') &&

  1447.             avi_read_idx1(s, size) >= 0) {

  1448.             avi->index_loaded=2;

  1449.             ret = 0;

  1450.         }else if(tag == MKTAG('L', 'I', 'S', 'T')) {

  1451.             uint32_t tag1 = avio_rl32(pb);

  1452. 

  1453.             if (tag1 == MKTAG('I', 'N', 'F', 'O'))

  1454.                 ff_read_riff_info(s, size - 4);

  1455.         }else if(!ret)

  1456.             break;

  1457. 

  1458.         if (avio_seek(pb, next, SEEK_SET) < 0)

  1459.             break; // something is wrong here

  1460.     }

  1461.  the_end:

  1462.     avio_seek(pb, pos, SEEK_SET);

  1463.     return ret;

  1464. }

  1465. 

  1466. static void seek_subtitle(AVStream *st, AVStream *st2, int64_t timestamp)

  1467. {

  1468.     AVIStream *ast2 = st2->priv_data;

  1469.     int64_t ts2 = av_rescale_q(timestamp, st->time_base, st2->time_base);

  1470.     av_free_packet(&ast2->sub_pkt);

  1471.     if (avformat_seek_file(ast2->sub_ctx, 0, INT64_MIN, ts2, ts2, 0) >= 0 ||

  1472.         avformat_seek_file(ast2->sub_ctx, 0, ts2, ts2, INT64_MAX, 0) >= 0)

  1473.         ff_read_packet(ast2->sub_ctx, &ast2->sub_pkt);

  1474. }

  1475. 

  1476. static int avi_read_seek(AVFormatContext *s, int stream_index, int64_t timestamp, int flags)

  1477. {

  1478.     AVIContext *avi = s->priv_data;

  1479.     AVStream *st;

  1480.     int i, index;

  1481.     int64_t pos, pos_min;

  1482.     AVIStream *ast;

  1483. 

  1484.     if (!avi->index_loaded) {

  1485.         /* we only load the index on demand */

  1486.         avi_load_index(s);

  1487.         avi->index_loaded |= 1;

  1488.     }

  1489.     av_assert0(stream_index>= 0);

  1490. 

  1491.     st = s->streams[stream_index];

  1492.     ast= st->priv_data;

  1493.     index= av_index_search_timestamp(st, timestamp * FFMAX(ast->sample_size, 1), flags);

  1494.     if (index<0) {

  1495.         if (st->nb_index_entries > 0)

  1496.             av_log(s, AV_LOG_DEBUG, "Failed to find timestamp %"PRId64 " in index %"PRId64 " .. %"PRId64 "\n",

  1497.                    timestamp * FFMAX(ast->sample_size, 1),

  1498.                    st->index_entries[0].timestamp,

  1499.                    st->index_entries[st->nb_index_entries - 1].timestamp);

  1500.         return AVERROR_INVALIDDATA;

  1501.     }

  1502. 

  1503.     /* find the position */

  1504.     pos = st->index_entries[index].pos;

  1505.     timestamp = st->index_entries[index].timestamp / FFMAX(ast->sample_size, 1);

  1506. 

  1507.     av_dlog(s, "XX %"PRId64" %d %"PRId64"\n",

  1508.             timestamp, index, st->index_entries[index].timestamp);

  1509. 

  1510.     if (CONFIG_DV_DEMUXER && avi->dv_demux) {

  1511.         /* One and only one real stream for DV in AVI, and it has video  */

  1512.         /* offsets. Calling with other stream indexes should have failed */

  1513.         /* the av_index_search_timestamp call above.                     */

  1514.         av_assert0(stream_index == 0);

  1515. 

  1516.         if(avio_seek(s->pb, pos, SEEK_SET) < 0)

  1517.             return -1;

  1518. 

  1519.         /* Feed the DV video stream version of the timestamp to the */

  1520.         /* DV demux so it can synthesize correct timestamps.        */

  1521.         ff_dv_offset_reset(avi->dv_demux, timestamp);

  1522. 

  1523.         avi->stream_index= -1;

  1524.         return 0;

  1525.     }

  1526. 

  1527.     pos_min= pos;

  1528.     for(i = 0; i < s->nb_streams; i++) {

  1529.         AVStream *st2 = s->streams[i];

  1530.         AVIStream *ast2 = st2->priv_data;

  1531. 

  1532.         ast2->packet_size=

  1533.         ast2->remaining= 0;

  1534. 

  1535.         if (ast2->sub_ctx) {

  1536.             seek_subtitle(st, st2, timestamp);

  1537.             continue;

  1538.         }

  1539. 

  1540.         if (st2->nb_index_entries <= 0)

  1541.             continue;

  1542. 

  1543. //        av_assert1(st2->codec->block_align);

  1544.         av_assert0((int64_t)st2->time_base.num*ast2->rate == (int64_t)st2->time_base.den*ast2->scale);

  1545.         index = av_index_search_timestamp(

  1546.                 st2,

  1547.                 av_rescale_q(timestamp, st->time_base, st2->time_base) * FFMAX(ast2->sample_size, 1),

  1548.                 flags | AVSEEK_FLAG_BACKWARD | (st2->codec->codec_type != AVMEDIA_TYPE_VIDEO ? AVSEEK_FLAG_ANY : 0));

  1549.         if(index<0)

  1550.             index=0;

  1551.         ast2->seek_pos= st2->index_entries[index].pos;

  1552.         pos_min= FFMIN(pos_min,ast2->seek_pos);

  1553.     }

  1554.     for(i = 0; i < s->nb_streams; i++) {

  1555.         AVStream *st2 = s->streams[i];

  1556.         AVIStream *ast2 = st2->priv_data;

  1557. 

  1558.         if (ast2->sub_ctx || st2->nb_index_entries <= 0)

  1559.             continue;

  1560. 

  1561.         index = av_index_search_timestamp(

  1562.                 st2,

  1563.                 av_rescale_q(timestamp, st->time_base, st2->time_base) * FFMAX(ast2->sample_size, 1),

  1564.                 flags | AVSEEK_FLAG_BACKWARD | (st2->codec->codec_type != AVMEDIA_TYPE_VIDEO ? AVSEEK_FLAG_ANY : 0));

  1565.         if(index<0)

  1566.             index=0;

  1567.         while(!avi->non_interleaved && index>0 && st2->index_entries[index-1].pos >= pos_min)

  1568.             index--;

  1569.         ast2->frame_offset = st2->index_entries[index].timestamp;

  1570.     }

  1571. 

  1572.     /* do the seek */

  1573.     if (avio_seek(s->pb, pos_min, SEEK_SET) < 0) {

  1574.         av_log(s, AV_LOG_ERROR, "Seek failed\n");

  1575.         return -1;

  1576.     }

  1577.     avi->stream_index= -1;

  1578.     avi->dts_max= INT_MIN;

  1579.     return 0;

  1580. }

  1581. 

  1582. static int avi_read_close(AVFormatContext *s)

  1583. {

  1584.     int i;

  1585.     AVIContext *avi = s->priv_data;

  1586. 

  1587.     for(i=0;i<s->nb_streams;i++) {

  1588.         AVStream *st = s->streams[i];

  1589.         AVIStream *ast = st->priv_data;

  1590.         if (ast) {

  1591.             if (ast->sub_ctx) {

  1592.                 av_freep(&ast->sub_ctx->pb);

  1593.                 avformat_close_input(&ast->sub_ctx);

  1594.             }

  1595.             av_free(ast->sub_buffer);

  1596.             av_free_packet(&ast->sub_pkt);

  1597.         }

  1598.     }

  1599. 

  1600.     av_free(avi->dv_demux);

  1601. 

  1602.     return 0;

  1603. }

  1604. 

  1605. static int avi_probe(AVProbeData *p)

  1606. {

  1607.     int i;

  1608. 

  1609.     /* check file header */

  1610.     for(i=0; avi_headers[i][0]; i++)

  1611.         if(!memcmp(p->buf  , avi_headers[i]  , 4) &&

  1612.            !memcmp(p->buf+8, avi_headers[i]+4, 4))

  1613.             return AVPROBE_SCORE_MAX;

  1614. 

  1615.     return 0;

  1616. }

  1617. 

  1618. AVInputFormat ff_avi_demuxer = {

  1619.     .name           = "avi",

  1620.     .long_name      = NULL_IF_CONFIG_SMALL("AVI (Audio Video Interleaved)"),

  1621.     .priv_data_size = sizeof(AVIContext),

  1622.     .read_probe     = avi_probe,

  1623.     .read_header    = avi_read_header,

  1624.     .read_packet    = avi_read_packet,

  1625.     .read_close     = avi_read_close,

  1626.     .read_seek      = avi_read_seek,

  1627.     .priv_class = &demuxer_class,

  1628. };