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FFmpeg/libavformat/avidec.c

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  1. /*

  2.  * AVI demuxer

  3.  * Copyright (c) 2001 Fabrice Bellard

  4.  *

  5.  * This file is part of Libav.

  6.  *

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

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

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

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

  11.  *

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

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

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

  15.  * Lesser General Public License for more details.

  16.  *

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

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

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

  20.  */

  21. 

  22. #include "libavutil/intreadwrite.h"

  23. #include "libavutil/mathematics.h"

  24. #include "libavutil/bswap.h"

  25. #include "libavutil/dict.h"

  26. #include "libavutil/avstring.h"

  27. #include "avformat.h"

  28. #include "internal.h"

  29. #include "avi.h"

  30. #include "dv.h"

  31. #include "riff.h"

  32. 

  33. #undef NDEBUG

  34. #include <assert.h>

  35. 

  36. typedef struct AVIStream {

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

  38.                          (used to compute the pts) */

  39.     int remaining;

  40.     int packet_size;

  41. 

  42.     uint32_t scale;

  43.     uint32_t rate;

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

  45. 

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

  47. 

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

  49.     int prefix_count;

  50.     uint32_t pal[256];

  51.     int has_pal;

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

  53. 

  54.     AVFormatContext *sub_ctx;

  55.     AVPacket sub_pkt;

  56.     uint8_t *sub_buffer;

  57. } AVIStream;

  58. 

  59. typedef struct {

  60.     int64_t  riff_end;

  61.     int64_t  movi_end;

  62.     int64_t  fsize;

  63.     int64_t movi_list;

  64.     int64_t last_pkt_pos;

  65.     int index_loaded;

  66.     int is_odml;

  67.     int non_interleaved;

  68.     int stream_index;

  69.     DVDemuxContext* dv_demux;

  70.     int odml_depth;

  71. #define MAX_ODML_DEPTH 1000

  72. } AVIContext;

  73. 

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

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

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

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

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

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

  80.     { 0 }

  81. };

  82. 

  83. static const AVMetadataConv avi_metadata_conv[] = {

  84.     { "strn", "title" },

  85.     { 0 },

  86. };

  87. 

  88. static int avi_load_index(AVFormatContext *s);

  89. static int guess_ni_flag(AVFormatContext *s);

  90. 

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

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

  93.            str, tag & 0xff,                             \

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

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

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

  97.            size)

  98. 

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

  100.     if(ast->sample_size){

  101.         return len;

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

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

  104.     }else

  105.         return 1;

  106. }

  107. 

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

  109. {

  110.     AVIContext *avi = s->priv_data;

  111.     char header[8];

  112.     int i;

  113. 

  114.     /* check RIFF header */

  115.     avio_read(pb, header, 4);

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

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

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

  119. 

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

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

  122.             break;

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

  124.         return AVERROR_INVALIDDATA;

  125. 

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

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

  128. 

  129.     return 0;

  130. }

  131. 

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

  133.     AVIContext *avi = s->priv_data;

  134.     AVIOContext *pb = s->pb;

  135.     int longs_pre_entry= avio_rl16(pb);

  136.     int index_sub_type = avio_r8(pb);

  137.     int index_type     = avio_r8(pb);

  138.     int entries_in_use = avio_rl32(pb);

  139.     int chunk_id       = avio_rl32(pb);

  140.     int64_t base       = avio_rl64(pb);

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

  142.     AVStream *st;

  143.     AVIStream *ast;

  144.     int i;

  145.     int64_t last_pos= -1;

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

  147. 

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

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

  150. 

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

  152.         return AVERROR_INVALIDDATA;

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

  154.     ast = st->priv_data;

  155. 

  156.     if(index_sub_type)

  157.         return AVERROR_INVALIDDATA;

  158. 

  159.     avio_rl32(pb);

  160. 

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

  162.         return AVERROR_INVALIDDATA;

  163.     if(index_type>1)

  164.         return AVERROR_INVALIDDATA;

  165. 

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

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

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

  169.             base &= 0xFFFFFFFF;

  170.         else

  171.             return AVERROR_INVALIDDATA;

  172.     }

  173. 

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

  175.         if(index_type){

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

  177.             int len    = avio_rl32(pb);

  178.             int key= len >= 0;

  179.             len &= 0x7FFFFFFF;

  180. 

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

  182. 

  183.             if(pb->eof_reached)

  184.                 return AVERROR_INVALIDDATA;

  185. 

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

  187.                 avi->non_interleaved= 1;

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

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

  190. 

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

  192.             last_pos= pos;

  193.         }else{

  194.             int64_t offset, pos;

  195.             int duration;

  196.             offset = avio_rl64(pb);

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

  198.             duration = avio_rl32(pb);

  199. 

  200.             if(pb->eof_reached)

  201.                 return AVERROR_INVALIDDATA;

  202. 

  203.             pos = avio_tell(pb);

  204. 

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

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

  207.                 return AVERROR_INVALIDDATA;

  208.             }

  209. 

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

  211.             avi->odml_depth++;

  212.             read_braindead_odml_indx(s, frame_num);

  213.             avi->odml_depth--;

  214.             frame_num += duration;

  215. 

  216.             avio_seek(pb, pos, SEEK_SET);

  217.         }

  218.     }

  219.     avi->index_loaded=1;

  220.     return 0;

  221. }

  222. 

  223. static void clean_index(AVFormatContext *s){

  224.     int i;

  225.     int64_t j;

  226. 

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

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

  229.         AVIStream *ast = st->priv_data;

  230.         int n= st->nb_index_entries;

  231.         int max= ast->sample_size;

  232.         int64_t pos, size, ts;

  233. 

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

  235.             continue;

  236. 

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

  238. 

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

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

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

  242. 

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

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

  245.         }

  246.     }

  247. }

  248. 

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

  250. {

  251.     AVIOContext *pb = s->pb;

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

  253. 

  254.     size += (size & 1);

  255. 

  256.     if (size == UINT_MAX)

  257.         return AVERROR(EINVAL);

  258.     value = av_malloc(size+1);

  259.     if (!value)

  260.         return AVERROR(ENOMEM);

  261.     avio_read(pb, value, size);

  262.     value[size]=0;

  263. 

  264.     AV_WL32(key, tag);

  265. 

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

  267.                             AV_DICT_DONT_STRDUP_VAL);

  268. }

  269. 

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

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

  272. 

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

  274. {

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

  276.     int i, day, year;

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

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

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

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

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

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

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

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

  285.             }

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

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

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

  289.     }

  290. }

  291. 

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

  293. {

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

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

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

  297.         switch (tag) {

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

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

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

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

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

  303.                 const char *name = NULL;

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

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

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

  307.                 switch (tag) {

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

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

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

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

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

  313.                     break;

  314.                 }

  315.                 if (name)

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

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

  318.             }

  319.             break;

  320.         }

  321.         default:

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

  323.             break;

  324.         }

  325.     }

  326. }

  327. 

  328. static int avi_read_header(AVFormatContext *s)

  329. {

  330.     AVIContext *avi = s->priv_data;

  331.     AVIOContext *pb = s->pb;

  332.     unsigned int tag, tag1, handler;

  333.     int codec_type, stream_index, frame_period;

  334.     unsigned int size;

  335.     int i;

  336.     AVStream *st;

  337.     AVIStream *ast = NULL;

  338.     int avih_width=0, avih_height=0;

  339.     int amv_file_format=0;

  340.     uint64_t list_end = 0;

  341.     int ret;

  342. 

  343.     avi->stream_index= -1;

  344. 

  345.     ret = get_riff(s, pb);

  346.     if (ret < 0)

  347.         return ret;

  348. 

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

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

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

  352. 

  353.     /* first list tag */

  354.     stream_index = -1;

  355.     codec_type = -1;

  356.     frame_period = 0;

  357.     for(;;) {

  358.         if (pb->eof_reached)

  359.             goto fail;

  360.         tag = avio_rl32(pb);

  361.         size = avio_rl32(pb);

  362. 

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

  364. 

  365.         switch(tag) {

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

  367.             list_end = avio_tell(pb) + size;

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

  369.             tag1 = avio_rl32(pb);

  370. 

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

  372. 

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

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

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

  376.                 else     avi->movi_end = avio_size(pb);

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

  378.                 goto end_of_header;

  379.             }

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

  381.                 ff_read_riff_info(s, size - 4);

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

  383.                 avi_read_nikon(s, list_end);

  384. 

  385.             break;

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

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

  388.             size += (size & 1);

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

  390.             avio_skip(pb, size);

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

  392.             break;

  393.         }

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

  395.             avi->is_odml = 1;

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

  397.             break;

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

  399.             amv_file_format=1;

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

  401.             /* AVI header */

  402.             /* using frame_period is bad idea */

  403.             frame_period = avio_rl32(pb);

  404.             avio_skip(pb, 4);

  405.             avio_rl32(pb);

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

  407. 

  408.             avio_skip(pb, 2 * 4);

  409.             avio_rl32(pb);

  410.             avio_rl32(pb);

  411.             avih_width=avio_rl32(pb);

  412.             avih_height=avio_rl32(pb);

  413. 

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

  415.             break;

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

  417.             /* stream header */

  418. 

  419.             tag1 = avio_rl32(pb);

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

  421. 

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

  423.                 avio_skip(pb, size - 8);

  424.                 break;

  425.             }else{

  426.                 stream_index++;

  427.                 st = avformat_new_stream(s, NULL);

  428.                 if (!st)

  429.                     goto fail;

  430. 

  431.                 st->id = stream_index;

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

  433.                 if (!ast)

  434.                     goto fail;

  435.                 st->priv_data = ast;

  436.             }

  437.             if(amv_file_format)

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

  439. 

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

  441. 

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

  443.                 int64_t dv_dur;

  444. 

  445.                 /*

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

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

  448.                  */

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

  450.                     goto fail;

  451. 

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

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

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

  455.                    goto fail;

  456. 

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

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

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

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

  461.                 s->nb_streams = 0;

  462.                 if (CONFIG_DV_DEMUXER) {

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

  464.                     if (!avi->dv_demux)

  465.                         goto fail;

  466.                 }

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

  468.                 avio_skip(pb, 3 * 4);

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

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

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

  472. 

  473.                 dv_dur = avio_rl32(pb);

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

  475.                     dv_dur *= AV_TIME_BASE;

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

  477.                 }

  478.                 /*

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

  480.                  *      will make a guess based on bitrate.

  481.                  */

  482. 

  483.                 stream_index = s->nb_streams - 1;

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

  485.                 break;

  486.             }

  487. 

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

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

  490. 

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

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

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

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

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

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

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

  498.                 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);

  499.                 if(frame_period){

  500.                     ast->rate = 1000000;

  501.                     ast->scale = frame_period;

  502.                 }else{

  503.                     ast->rate = 25;

  504.                     ast->scale = 1;

  505.                 }

  506.             }

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

  508. 

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

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

  511. 

  512.             st->start_time = 0;

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

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

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

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

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

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

  519. 

  520.             switch(tag1) {

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

  522.                 codec_type = AVMEDIA_TYPE_VIDEO;

  523. 

  524.                 ast->sample_size = 0;

  525.                 break;

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

  527.                 codec_type = AVMEDIA_TYPE_AUDIO;

  528.                 break;

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

  530.                 codec_type = AVMEDIA_TYPE_SUBTITLE;

  531.                 break;

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

  533.                 codec_type = AVMEDIA_TYPE_DATA;

  534.                 break;

  535.             default:

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

  537.                 goto fail;

  538.             }

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

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

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

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

  543.             break;

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

  545.             /* stream header */

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

  547.                 avio_skip(pb, size);

  548.             } else {

  549.                 uint64_t cur_pos = avio_tell(pb);

  550.                 if (cur_pos < list_end)

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

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

  553.                 switch(codec_type) {

  554.                 case AVMEDIA_TYPE_VIDEO:

  555.                     if(amv_file_format){

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

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

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

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

  560.                         avio_skip(pb, size);

  561.                         break;

  562.                     }

  563.                     tag1 = ff_get_bmp_header(pb, st);

  564. 

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

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

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

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

  569.                         break;

  570.                     }

  571. 

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

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

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

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

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

  577.                             return AVERROR(ENOMEM);

  578.                         }

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

  580.                     }

  581. 

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

  583.                         avio_r8(pb);

  584. 

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

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

  587.                     /* This is true for all paletted codecs implemented in Libav. */

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

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

  590.                         const uint8_t *pal_src;

  591. 

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

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

  594. #if HAVE_BIGENDIAN

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

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

  597. #else

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

  599. #endif

  600.                         ast->has_pal = 1;

  601.                     }

  602. 

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

  604. 

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

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

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

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

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

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

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

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

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

  614. 

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

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

  617.                         st->codec->extradata= av_realloc(st->codec->extradata, st->codec->extradata_size + FF_INPUT_BUFFER_PADDING_SIZE);

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

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

  620.                     }

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

  622. 

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

  624.                     break;

  625.                 case AVMEDIA_TYPE_AUDIO:

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

  627.                     if (ret < 0)

  628.                         return ret;

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

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

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

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

  633.                     }

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

  635.                         avio_skip(pb, 1);

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

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

  638.                     st->need_parsing = AVSTREAM_PARSE_TIMESTAMPS;

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

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

  641.                      * fail. */

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

  643.                         st->need_parsing = AVSTREAM_PARSE_NONE;

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

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

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

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

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

  649.                     }

  650.                     if (amv_file_format){

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

  652.                         ast->dshow_block_align = 0;

  653.                     }

  654.                     break;

  655.                 case AVMEDIA_TYPE_SUBTITLE:

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

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

  658.                     break;

  659.                 default:

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

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

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

  663.                     avio_skip(pb, size);

  664.                     break;

  665.                 }

  666.             }

  667.             break;

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

  669.             i= avio_tell(pb);

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

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

  672.                (s->error_recognition & AV_EF_EXPLODE))

  673.                 goto fail;

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

  675.             break;

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

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

  678.                 AVRational active, active_aspect;

  679. 

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

  681.                 avio_rl32(pb);

  682.                 avio_rl32(pb);

  683.                 avio_rl32(pb);

  684.                 avio_rl32(pb);

  685.                 avio_rl32(pb);

  686. 

  687.                 active_aspect.den= avio_rl16(pb);

  688.                 active_aspect.num= avio_rl16(pb);

  689.                 active.num       = avio_rl32(pb);

  690.                 active.den       = avio_rl32(pb);

  691.                 avio_rl32(pb); //nbFieldsPerFrame

  692. 

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

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

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

  696.                             active_aspect.num, active_aspect.den,

  697.                             active.num, active.den);

  698.                 }

  699.                 size -= 9*4;

  700.             }

  701.             avio_skip(pb, size);

  702.             break;

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

  704.             if(s->nb_streams){

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

  706.                 if (ret < 0)

  707.                     return ret;

  708.                 break;

  709.             }

  710.         default:

  711.             if(size > 1000000){

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

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

  714.                 if (s->error_recognition & AV_EF_EXPLODE)

  715.                     goto fail;

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

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

  718.                 goto end_of_header;

  719.             }

  720.             /* skip tag */

  721.             size += (size & 1);

  722.             avio_skip(pb, size);

  723.             break;

  724.         }

  725.     }

  726.  end_of_header:

  727.     /* check stream number */

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

  729.     fail:

  730.         return AVERROR_INVALIDDATA;

  731.     }

  732. 

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

  734.         avi_load_index(s);

  735.     avi->index_loaded = 1;

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

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

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

  739.         if(st->nb_index_entries)

  740.             break;

  741.     }

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

  743.         av_log(s, AV_LOG_WARNING, "non-interleaved AVI without index, switching to interleaved\n");

  744.         avi->non_interleaved=0;

  745.     }

  746. 

  747.     if(avi->non_interleaved) {

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

  749.         clean_index(s);

  750.     }

  751. 

  752.     ff_metadata_conv_ctx(s, NULL, avi_metadata_conv);

  753.     ff_metadata_conv_ctx(s, NULL, ff_riff_info_conv);

  754. 

  755.     return 0;

  756. }

  757. 

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

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

  760.         uint8_t desc[256];

  761.         int score = AVPROBE_SCORE_MAX / 2, ret;

  762.         AVIStream *ast = st->priv_data;

  763.         AVInputFormat *sub_demuxer;

  764.         AVRational time_base;

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

  766.                                               pkt->size - 7,

  767.                                               0, NULL, NULL, NULL, NULL);

  768.         AVProbeData pd;

  769.         unsigned int desc_len = avio_rl32(pb);

  770. 

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

  772.             goto error;

  773. 

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

  775.         avio_skip(pb, desc_len - ret);

  776.         if (*desc)

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

  778. 

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

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

  781. 

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

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

  784.             goto error;

  785. 

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

  787.             goto error;

  788. 

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

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

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

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

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

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

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

  796.         }

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

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

  799.         return 1;

  800. error:

  801.         av_freep(&pb);

  802.     }

  803.     return 0;

  804. }

  805. 

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

  807.                                   AVPacket *pkt)

  808. {

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

  810.     int64_t ts, next_ts, ts_min = INT64_MAX;

  811.     AVStream *st, *sub_st = NULL;

  812.     int i;

  813. 

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

  815.                            AV_TIME_BASE_Q);

  816. 

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

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

  819.         ast = st->priv_data;

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

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

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

  823.                 ts_min = ts;

  824.                 sub_st = st;

  825.             }

  826.         }

  827.     }

  828. 

  829.     if (sub_st) {

  830.         ast = sub_st->priv_data;

  831.         *pkt = ast->sub_pkt;

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

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

  834.             ast->sub_pkt.data = NULL;

  835.     }

  836.     return sub_st;

  837. }

  838. 

  839. static int get_stream_idx(int *d){

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

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

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

  843.     }else{

  844.         return 100; //invalid stream ID

  845.     }

  846. }

  847. 

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

  849. {

  850.     AVIContext *avi = s->priv_data;

  851.     AVIOContext *pb = s->pb;

  852.     int n;

  853.     unsigned int d[8];

  854.     unsigned int size;

  855.     int64_t i, sync;

  856. 

  857. start_sync:

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

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

  860.         int j;

  861. 

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

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

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

  865. 

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

  867. 

  868.         n= get_stream_idx(d+2);

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

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

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

  872.             continue;

  873. 

  874.         //parse ix##

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

  876.         //parse JUNK

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

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

  879.             avio_skip(pb, size);

  880.             goto start_sync;

  881.         }

  882. 

  883.         //parse stray LIST

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

  885.             avio_skip(pb, 4);

  886.             goto start_sync;

  887.         }

  888. 

  889.         n= get_stream_idx(d);

  890. 

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

  892.             continue;

  893. 

  894.         //detect ##ix chunk and skip

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

  896.             avio_skip(pb, size);

  897.             goto start_sync;

  898.         }

  899. 

  900.         //parse ##dc/##wb

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

  902.             AVStream *st;

  903.             AVIStream *ast;

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

  905.             ast = st->priv_data;

  906. 

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

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

  909.                 AVIStream *ast1= st1->priv_data;

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

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

  912.                    && n==0

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

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

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

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

  917.                   ){

  918.                     n=1;

  919.                     st = st1;

  920.                     ast = ast1;

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

  922.                 }

  923.             }

  924. 

  925. 

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

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

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

  929.                 if (!exit_early) {

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

  931.                 }

  932.                 avio_skip(pb, size);

  933.                 goto start_sync;

  934.             }

  935. 

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

  937.                 int k = avio_r8(pb);

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

  939. 

  940.                 avio_rl16(pb); //flags

  941. 

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

  943.                     ast->pal[k] = avio_rb32(pb)>>8;// b + (g << 8) + (r << 16);

  944.                 ast->has_pal= 1;

  945.                 goto start_sync;

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

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

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

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

  950. 

  951.                 if (exit_early)

  952.                     return 0;

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

  954.                     ast->prefix_count++;

  955.                 else{

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

  957.                     ast->prefix_count= 0;

  958.                 }

  959. 

  960.                 avi->stream_index= n;

  961.                 ast->packet_size= size + 8;

  962.                 ast->remaining= size;

  963. 

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

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

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

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

  968.                     }

  969.                 }

  970.                 return 0;

  971.             }

  972.         }

  973.     }

  974. 

  975.     return AVERROR_EOF;

  976. }

  977. 

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

  979. {

  980.     AVIContext *avi = s->priv_data;

  981.     AVIOContext *pb = s->pb;

  982.     int err;

  983. #if FF_API_DESTRUCT_PACKET

  984.     void* dstr;

  985. #endif

  986. 

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

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

  989.         if (size >= 0)

  990.             return size;

  991.     }

  992. 

  993.     if(avi->non_interleaved){

  994.         int best_stream_index = 0;

  995.         AVStream *best_st= NULL;

  996.         AVIStream *best_ast;

  997.         int64_t best_ts= INT64_MAX;

  998.         int i;

  999. 

  1000.         for(i=0; i<s->nb_streams; i++){

  1001.             AVStream *st = s->streams[i];

  1002.             AVIStream *ast = st->priv_data;

  1003.             int64_t ts= ast->frame_offset;

  1004.             int64_t last_ts;

  1005. 

  1006.             if(!st->nb_index_entries)

  1007.                 continue;

  1008. 

  1009.             last_ts = st->index_entries[st->nb_index_entries - 1].timestamp;

  1010.             if(!ast->remaining && ts > last_ts)

  1011.                 continue;

  1012. 

  1013.             ts = av_rescale_q(ts, st->time_base, (AVRational){FFMAX(1, ast->sample_size), AV_TIME_BASE});

  1014. 

  1015.             av_dlog(s, "%"PRId64" %d/%d %"PRId64"\n", ts,

  1016.                     st->time_base.num, st->time_base.den, ast->frame_offset);

  1017.             if(ts < best_ts){

  1018.                 best_ts= ts;

  1019.                 best_st= st;

  1020.                 best_stream_index= i;

  1021.             }

  1022.         }

  1023.         if(!best_st)

  1024.             return AVERROR_EOF;

  1025. 

  1026.         best_ast = best_st->priv_data;

  1027.         best_ts = av_rescale_q(best_ts, (AVRational){FFMAX(1, best_ast->sample_size), AV_TIME_BASE}, best_st->time_base);

  1028.         if(best_ast->remaining)

  1029.             i= av_index_search_timestamp(best_st, best_ts, AVSEEK_FLAG_ANY | AVSEEK_FLAG_BACKWARD);

  1030.         else{

  1031.             i= av_index_search_timestamp(best_st, best_ts, AVSEEK_FLAG_ANY);

  1032.             if(i>=0)

  1033.                 best_ast->frame_offset= best_st->index_entries[i].timestamp;

  1034.         }

  1035. 

  1036.         if(i>=0){

  1037.             int64_t pos= best_st->index_entries[i].pos;

  1038.             pos += best_ast->packet_size - best_ast->remaining;

  1039.             avio_seek(s->pb, pos + 8, SEEK_SET);

  1040. 

  1041.             assert(best_ast->remaining <= best_ast->packet_size);

  1042. 

  1043.             avi->stream_index= best_stream_index;

  1044.             if(!best_ast->remaining)

  1045.                 best_ast->packet_size=

  1046.                 best_ast->remaining= best_st->index_entries[i].size;

  1047.         }

  1048.     }

  1049. 

  1050. resync:

  1051.     if(avi->stream_index >= 0){

  1052.         AVStream *st= s->streams[ avi->stream_index ];

  1053.         AVIStream *ast= st->priv_data;

  1054.         int size, err;

  1055. 

  1056.         if(get_subtitle_pkt(s, st, pkt))

  1057.             return 0;

  1058. 

  1059.         if(ast->sample_size <= 1) // minorityreport.AVI block_align=1024 sample_size=1 IMA-ADPCM

  1060.             size= INT_MAX;

  1061.         else if(ast->sample_size < 32)

  1062.             // arbitrary multiplier to avoid tiny packets for raw PCM data

  1063.             size= 1024*ast->sample_size;

  1064.         else

  1065.             size= ast->sample_size;

  1066. 

  1067.         if(size > ast->remaining)

  1068.             size= ast->remaining;

  1069.         avi->last_pkt_pos= avio_tell(pb);

  1070.         err= av_get_packet(pb, pkt, size);

  1071.         if(err<0)

  1072.             return err;

  1073. 

  1074.         if(ast->has_pal && pkt->data && pkt->size<(unsigned)INT_MAX/2){

  1075.             uint8_t *pal;

  1076.             pal = av_packet_new_side_data(pkt, AV_PKT_DATA_PALETTE, AVPALETTE_SIZE);

  1077.             if(!pal){

  1078.                 av_log(s, AV_LOG_ERROR, "Failed to allocate data for palette\n");

  1079.             }else{

  1080.                 memcpy(pal, ast->pal, AVPALETTE_SIZE);

  1081.                 ast->has_pal = 0;

  1082.             }

  1083.         }

  1084. 

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

  1086.             AVBufferRef *avbuf = pkt->buf;

  1087. #if FF_API_DESTRUCT_PACKET

  1088.             dstr = pkt->destruct;

  1089. #endif

  1090.             size = avpriv_dv_produce_packet(avi->dv_demux, pkt,

  1091.                                     pkt->data, pkt->size);

  1092. #if FF_API_DESTRUCT_PACKET

  1093.             pkt->destruct = dstr;

  1094. #endif

  1095.             pkt->buf = avbuf;

  1096.             pkt->flags |= AV_PKT_FLAG_KEY;

  1097.             if (size < 0)

  1098.                 av_free_packet(pkt);

  1099.         } else if (st->codec->codec_type == AVMEDIA_TYPE_SUBTITLE

  1100.                    && !st->codec->codec_tag && read_gab2_sub(st, pkt)) {

  1101.             ast->frame_offset++;

  1102.             avi->stream_index = -1;

  1103.             ast->remaining = 0;

  1104.             goto resync;

  1105.         } else {

  1106.             /* XXX: How to handle B-frames in AVI? */

  1107.             pkt->dts = ast->frame_offset;

  1108. //                pkt->dts += ast->start;

  1109.             if(ast->sample_size)

  1110.                 pkt->dts /= ast->sample_size;

  1111.             av_dlog(s, "dts:%"PRId64" offset:%"PRId64" %d/%d smpl_siz:%d base:%d st:%d size:%d\n",

  1112.                     pkt->dts, ast->frame_offset, ast->scale, ast->rate,

  1113.                     ast->sample_size, AV_TIME_BASE, avi->stream_index, size);

  1114.             pkt->stream_index = avi->stream_index;

  1115. 

  1116.             if (st->codec->codec_type == AVMEDIA_TYPE_VIDEO) {

  1117.                 AVIndexEntry *e;

  1118.                 int index;

  1119.                 assert(st->index_entries);

  1120. 

  1121.                 index= av_index_search_timestamp(st, ast->frame_offset, 0);

  1122.                 e= &st->index_entries[index];

  1123. 

  1124.                 if(index >= 0 && e->timestamp == ast->frame_offset){

  1125.                     if (e->flags & AVINDEX_KEYFRAME)

  1126.                         pkt->flags |= AV_PKT_FLAG_KEY;

  1127.                 }

  1128.             } else {

  1129.                 pkt->flags |= AV_PKT_FLAG_KEY;

  1130.             }

  1131.             ast->frame_offset += get_duration(ast, pkt->size);

  1132.         }

  1133.         ast->remaining -= err;

  1134.         if(!ast->remaining){

  1135.             avi->stream_index= -1;

  1136.             ast->packet_size= 0;

  1137.         }

  1138. 

  1139.         return 0;

  1140.     }

  1141. 

  1142.     if ((err = avi_sync(s, 0)) < 0)

  1143.         return err;

  1144.     goto resync;

  1145. }

  1146. 

  1147. /* XXX: We make the implicit supposition that the positions are sorted

  1148.    for each stream. */

  1149. static int avi_read_idx1(AVFormatContext *s, int size)

  1150. {

  1151.     AVIContext *avi = s->priv_data;

  1152.     AVIOContext *pb = s->pb;

  1153.     int nb_index_entries, i;

  1154.     AVStream *st;

  1155.     AVIStream *ast;

  1156.     unsigned int index, tag, flags, pos, len, first_packet = 1;

  1157.     unsigned last_pos= -1;

  1158.     int64_t idx1_pos, first_packet_pos = 0, data_offset = 0;

  1159. 

  1160.     nb_index_entries = size / 16;

  1161.     if (nb_index_entries <= 0)

  1162.         return AVERROR_INVALIDDATA;

  1163. 

  1164.     idx1_pos = avio_tell(pb);

  1165.     avio_seek(pb, avi->movi_list+4, SEEK_SET);

  1166.     if (avi_sync(s, 1) == 0) {

  1167.         first_packet_pos = avio_tell(pb) - 8;

  1168.     }

  1169.     avi->stream_index = -1;

  1170.     avio_seek(pb, idx1_pos, SEEK_SET);

  1171. 

  1172.     /* Read the entries and sort them in each stream component. */

  1173.     for(i = 0; i < nb_index_entries; i++) {

  1174.         tag = avio_rl32(pb);

  1175.         flags = avio_rl32(pb);

  1176.         pos = avio_rl32(pb);

  1177.         len = avio_rl32(pb);

  1178.         av_dlog(s, "%d: tag=0x%x flags=0x%x pos=0x%x len=%d/",

  1179.                 i, tag, flags, pos, len);

  1180. 

  1181.         index = ((tag & 0xff) - '0') * 10;

  1182.         index += ((tag >> 8) & 0xff) - '0';

  1183.         if (index >= s->nb_streams)

  1184.             continue;

  1185.         st = s->streams[index];

  1186.         ast = st->priv_data;

  1187. 

  1188.         if(first_packet && first_packet_pos && len) {

  1189.             data_offset = first_packet_pos - pos;

  1190.             first_packet = 0;

  1191.         }

  1192.         pos += data_offset;

  1193. 

  1194.         av_dlog(s, "%d cum_len=%"PRId64"\n", len, ast->cum_len);

  1195. 

  1196.         if(pb->eof_reached)

  1197.             return AVERROR_INVALIDDATA;

  1198. 

  1199.         if(last_pos == pos)

  1200.             avi->non_interleaved= 1;

  1201.         else if(len || !ast->sample_size)

  1202.             av_add_index_entry(st, pos, ast->cum_len, len, 0, (flags&AVIIF_INDEX) ? AVINDEX_KEYFRAME : 0);

  1203.         ast->cum_len += get_duration(ast, len);

  1204.         last_pos= pos;

  1205.     }

  1206.     return 0;

  1207. }

  1208. 

  1209. static int guess_ni_flag(AVFormatContext *s){

  1210.     int i;

  1211.     int64_t last_start=0;

  1212.     int64_t first_end= INT64_MAX;

  1213.     int64_t oldpos= avio_tell(s->pb);

  1214. 

  1215.     for(i=0; i<s->nb_streams; i++){

  1216.         AVStream *st = s->streams[i];

  1217.         int n= st->nb_index_entries;

  1218.         unsigned int size;

  1219. 

  1220.         if(n <= 0)

  1221.             continue;

  1222. 

  1223.         if(n >= 2){

  1224.             int64_t pos= st->index_entries[0].pos;

  1225.             avio_seek(s->pb, pos + 4, SEEK_SET);

  1226.             size= avio_rl32(s->pb);

  1227.             if(pos + size > st->index_entries[1].pos)

  1228.                 last_start= INT64_MAX;

  1229.         }

  1230. 

  1231.         if(st->index_entries[0].pos > last_start)

  1232.             last_start= st->index_entries[0].pos;

  1233.         if(st->index_entries[n-1].pos < first_end)

  1234.             first_end= st->index_entries[n-1].pos;

  1235.     }

  1236.     avio_seek(s->pb, oldpos, SEEK_SET);

  1237.     return last_start > first_end;

  1238. }

  1239. 

  1240. static int avi_load_index(AVFormatContext *s)

  1241. {

  1242.     AVIContext *avi = s->priv_data;

  1243.     AVIOContext *pb = s->pb;

  1244.     uint32_t tag, size;

  1245.     int64_t pos= avio_tell(pb);

  1246.     int ret = -1;

  1247. 

  1248.     if (avio_seek(pb, avi->movi_end, SEEK_SET) < 0)

  1249.         goto the_end; // maybe truncated file

  1250.     av_dlog(s, "movi_end=0x%"PRIx64"\n", avi->movi_end);

  1251.     for(;;) {

  1252.         if (pb->eof_reached)

  1253.             break;

  1254.         tag = avio_rl32(pb);

  1255.         size = avio_rl32(pb);

  1256.         av_dlog(s, "tag=%c%c%c%c size=0x%x\n",

  1257.                  tag        & 0xff,

  1258.                 (tag >>  8) & 0xff,

  1259.                 (tag >> 16) & 0xff,

  1260.                 (tag >> 24) & 0xff,

  1261.                 size);

  1262. 

  1263.         if (tag == MKTAG('i', 'd', 'x', '1') &&

  1264.             avi_read_idx1(s, size) >= 0) {

  1265.             ret = 0;

  1266.             break;

  1267.         }

  1268. 

  1269.         size += (size & 1);

  1270.         if (avio_skip(pb, size) < 0)

  1271.             break; // something is wrong here

  1272.     }

  1273.  the_end:

  1274.     avio_seek(pb, pos, SEEK_SET);

  1275.     return ret;

  1276. }

  1277. 

  1278. static void seek_subtitle(AVStream *st, AVStream *st2, int64_t timestamp)

  1279. {

  1280.     AVIStream *ast2 = st2->priv_data;

  1281.     int64_t ts2 = av_rescale_q(timestamp, st->time_base, st2->time_base);

  1282.     av_free_packet(&ast2->sub_pkt);

  1283.     if (avformat_seek_file(ast2->sub_ctx, 0, INT64_MIN, ts2, ts2, 0) >= 0 ||

  1284.         avformat_seek_file(ast2->sub_ctx, 0, ts2, ts2, INT64_MAX, 0) >= 0)

  1285.         ff_read_packet(ast2->sub_ctx, &ast2->sub_pkt);

  1286. }

  1287. 

  1288. static int avi_read_seek(AVFormatContext *s, int stream_index, int64_t timestamp, int flags)

  1289. {

  1290.     AVIContext *avi = s->priv_data;

  1291.     AVStream *st;

  1292.     int i, index;

  1293.     int64_t pos;

  1294.     AVIStream *ast;

  1295. 

  1296.     if (!avi->index_loaded) {

  1297.         /* we only load the index on demand */

  1298.         avi_load_index(s);

  1299.         avi->index_loaded = 1;

  1300.     }

  1301.     assert(stream_index>= 0);

  1302. 

  1303.     st = s->streams[stream_index];

  1304.     ast= st->priv_data;

  1305.     index= av_index_search_timestamp(st, timestamp * FFMAX(ast->sample_size, 1), flags);

  1306.     if(index<0)

  1307.         return AVERROR_INVALIDDATA;

  1308. 

  1309.     /* find the position */

  1310.     pos = st->index_entries[index].pos;

  1311.     timestamp = st->index_entries[index].timestamp / FFMAX(ast->sample_size, 1);

  1312. 

  1313.     av_dlog(s, "XX %"PRId64" %d %"PRId64"\n",

  1314.             timestamp, index, st->index_entries[index].timestamp);

  1315. 

  1316.     if (CONFIG_DV_DEMUXER && avi->dv_demux) {

  1317.         /* One and only one real stream for DV in AVI, and it has video  */

  1318.         /* offsets. Calling with other stream indexes should have failed */

  1319.         /* the av_index_search_timestamp call above.                     */

  1320.         assert(stream_index == 0);

  1321. 

  1322.         /* Feed the DV video stream version of the timestamp to the */

  1323.         /* DV demux so it can synthesize correct timestamps.        */

  1324.         ff_dv_offset_reset(avi->dv_demux, timestamp);

  1325. 

  1326.         avio_seek(s->pb, pos, SEEK_SET);

  1327.         avi->stream_index= -1;

  1328.         return 0;

  1329.     }

  1330. 

  1331.     for(i = 0; i < s->nb_streams; i++) {

  1332.         AVStream *st2 = s->streams[i];

  1333.         AVIStream *ast2 = st2->priv_data;

  1334. 

  1335.         ast2->packet_size=

  1336.         ast2->remaining= 0;

  1337. 

  1338.         if (ast2->sub_ctx) {

  1339.             seek_subtitle(st, st2, timestamp);

  1340.             continue;

  1341.         }

  1342. 

  1343.         if (st2->nb_index_entries <= 0)

  1344.             continue;

  1345. 

  1346. //        assert(st2->codec->block_align);

  1347.         assert((int64_t)st2->time_base.num*ast2->rate == (int64_t)st2->time_base.den*ast2->scale);

  1348.         index = av_index_search_timestamp(

  1349.                 st2,

  1350.                 av_rescale_q(timestamp, st->time_base, st2->time_base) * FFMAX(ast2->sample_size, 1),

  1351.                 flags | AVSEEK_FLAG_BACKWARD);

  1352.         if(index<0)

  1353.             index=0;

  1354. 

  1355.         if(!avi->non_interleaved){

  1356.             while(index>0 && st2->index_entries[index].pos > pos)

  1357.                 index--;

  1358.             while(index+1 < st2->nb_index_entries && st2->index_entries[index].pos < pos)

  1359.                 index++;

  1360.         }

  1361. 

  1362.         av_dlog(s, "%"PRId64" %d %"PRId64"\n",

  1363.                 timestamp, index, st2->index_entries[index].timestamp);

  1364.         /* extract the current frame number */

  1365.         ast2->frame_offset = st2->index_entries[index].timestamp;

  1366.     }

  1367. 

  1368.     /* do the seek */

  1369.     avio_seek(s->pb, pos, SEEK_SET);

  1370.     avi->stream_index= -1;

  1371.     return 0;

  1372. }

  1373. 

  1374. static int avi_read_close(AVFormatContext *s)

  1375. {

  1376.     int i;

  1377.     AVIContext *avi = s->priv_data;

  1378. 

  1379.     for(i=0;i<s->nb_streams;i++) {

  1380.         AVStream *st = s->streams[i];

  1381.         AVIStream *ast = st->priv_data;

  1382.         if (ast) {

  1383.             if (ast->sub_ctx) {

  1384.                 av_freep(&ast->sub_ctx->pb);

  1385.                 avformat_close_input(&ast->sub_ctx);

  1386.             }

  1387.             av_free(ast->sub_buffer);

  1388.             av_free_packet(&ast->sub_pkt);

  1389.         }

  1390.     }

  1391. 

  1392.     av_free(avi->dv_demux);

  1393. 

  1394.     return 0;

  1395. }

  1396. 

  1397. static int avi_probe(AVProbeData *p)

  1398. {

  1399.     int i;

  1400. 

  1401.     /* check file header */

  1402.     for(i=0; avi_headers[i][0]; i++)

  1403.         if(!memcmp(p->buf  , avi_headers[i]  , 4) &&

  1404.            !memcmp(p->buf+8, avi_headers[i]+4, 4))

  1405.             return AVPROBE_SCORE_MAX;

  1406. 

  1407.     return 0;

  1408. }

  1409. 

  1410. AVInputFormat ff_avi_demuxer = {

  1411.     .name           = "avi",

  1412.     .long_name      = NULL_IF_CONFIG_SMALL("AVI (Audio Video Interleaved)"),

  1413.     .priv_data_size = sizeof(AVIContext),

  1414.     .read_probe     = avi_probe,

  1415.     .read_header    = avi_read_header,

  1416.     .read_packet    = avi_read_packet,

  1417.     .read_close     = avi_read_close,

  1418.     .read_seek      = avi_read_seek,

  1419. };