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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 "avformat.h"

  29. #include "internal.h"

  30. #include "avi.h"

  31. #include "dv.h"

  32. #include "riff.h"

  33. 

  34. #undef NDEBUG

  35. #include <assert.h>

  36. 

  37. typedef struct AVIStream {

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

  39.                          (used to compute the pts) */

  40.     int remaining;

  41.     int packet_size;

  42. 

  43.     int scale;

  44.     int rate;

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

  46. 

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

  48. 

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

  50.     int prefix_count;

  51.     uint32_t pal[256];

  52.     int has_pal;

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

  54. 

  55.     AVFormatContext *sub_ctx;

  56.     AVPacket sub_pkt;

  57.     uint8_t *sub_buffer;

  58. 

  59.     int64_t seek_pos;

  60. } AVIStream;

  61. 

  62. typedef struct {

  63.     const AVClass *class;

  64.     int64_t  riff_end;

  65.     int64_t  movi_end;

  66.     int64_t  fsize;

  67.     int64_t movi_list;

  68.     int64_t last_pkt_pos;

  69.     int index_loaded;

  70.     int is_odml;

  71.     int non_interleaved;

  72.     int stream_index;

  73.     DVDemuxContext* dv_demux;

  74.     int odml_depth;

  75.     int use_odml;

  76. #define MAX_ODML_DEPTH 1000

  77.     int64_t dts_max;

  78. } AVIContext;

  79. 

  80. 

  81. static const AVOption options[] = {

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

  83.     { NULL },

  84. };

  85. 

  86. static const AVClass demuxer_class = {

  87.     "AVI demuxer",

  88.     av_default_item_name,

  89.     options,

  90.     LIBAVUTIL_VERSION_INT,

  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 -1;

  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 -1;

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

  174.     ast = st->priv_data;

  175. 

  176.     if(index_sub_type)

  177.         return -1;

  178. 

  179.     avio_rl32(pb);

  180. 

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

  182.         return -1;

  183.     if(index_type>1)

  184.         return -1;

  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 -1;

  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 -1;

  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 -1;

  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 -1;

  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");

  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 -1;

  284.     value = av_malloc(size+1);

  285.     if (!value)

  286.         return -1;

  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, AVFormatParameters *ap)

  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. 

  369.     avi->stream_index= -1;

  370. 

  371.     if (get_riff(s, pb) < 0)

  372.         return -1;

  373. 

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

  375. 

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

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

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

  379. 

  380.     /* first list tag */

  381.     stream_index = -1;

  382.     codec_type = -1;

  383.     frame_period = 0;

  384.     for(;;) {

  385.         if (url_feof(pb))

  386.             goto fail;

  387.         tag = avio_rl32(pb);

  388.         size = avio_rl32(pb);

  389. 

  390.         if(size > avi->fsize){

  391.             av_log(s, AV_LOG_ERROR, "chunk size is too big during header parsing\n");

  392.             goto fail;

  393.         }

  394. 

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

  396. 

  397.         switch(tag) {

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

  399.             list_end = avio_tell(pb) + size;

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

  401.             tag1 = avio_rl32(pb);

  402. 

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

  404. 

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

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

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

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

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

  410.                 goto end_of_header;

  411.             }

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

  413.                 ff_read_riff_info(s, size - 4);

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

  415.                 avi_read_nikon(s, list_end);

  416. 

  417.             break;

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

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

  420.             size += (size & 1);

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

  422.             avio_skip(pb, size);

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

  424.             break;

  425.         }

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

  427.             avi->is_odml = 1;

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

  429.             break;

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

  431.             amv_file_format=1;

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

  433.             /* AVI header */

  434.             /* using frame_period is bad idea */

  435.             frame_period = avio_rl32(pb);

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

  437.             avio_rl32(pb);

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

  439. 

  440.             avio_skip(pb, 2 * 4);

  441.             avio_rl32(pb);

  442.             avio_rl32(pb);

  443.             avih_width=avio_rl32(pb);

  444.             avih_height=avio_rl32(pb);

  445. 

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

  447.             break;

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

  449.             /* stream header */

  450. 

  451.             tag1 = avio_rl32(pb);

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

  453. 

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

  455.                 avio_skip(pb, size - 8);

  456.                 break;

  457.             }else{

  458.                 stream_index++;

  459.                 st = avformat_new_stream(s, NULL);

  460.                 if (!st)

  461.                     goto fail;

  462. 

  463.                 st->id = stream_index;

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

  465.                 if (!ast)

  466.                     goto fail;

  467.                 st->priv_data = ast;

  468.             }

  469.             if(amv_file_format)

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

  471. 

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

  473. 

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

  475.                 int64_t dv_dur;

  476. 

  477.                 /*

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

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

  480.                  */

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

  482.                     goto fail;

  483. 

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

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

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

  487.                    goto fail;

  488. 

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

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

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

  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.             assert(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_log(s, AV_LOG_DEBUG, "%d %d %d %d\n", ast->rate, ast->scale, ast->start, ast->sample_size);

  554. 

  555.             switch(tag1) {

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

  557.                 codec_type = AVMEDIA_TYPE_VIDEO;

  558. 

  559.                 ast->sample_size = 0;

  560.                 break;

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

  562.                 codec_type = AVMEDIA_TYPE_AUDIO;

  563.                 break;

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

  565.                 codec_type = AVMEDIA_TYPE_SUBTITLE;

  566.                 break;

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

  568.                 codec_type = AVMEDIA_TYPE_DATA;

  569.                 break;

  570.             default:

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

  572.             }

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

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

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

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

  577.             break;

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

  579.             /* stream header */

  580.             if (!size)

  581.                 break;

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

  583.                 avio_skip(pb, size);

  584.             } else {

  585.                 uint64_t cur_pos = avio_tell(pb);

  586.                 if (cur_pos < list_end)

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

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

  589.                 switch(codec_type) {

  590.                 case AVMEDIA_TYPE_VIDEO:

  591.                     if(amv_file_format){

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

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

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

  595.                         st->codec->codec_id = CODEC_ID_AMV;

  596.                         avio_skip(pb, size);

  597.                         break;

  598.                     }

  599.                     tag1 = ff_get_bmp_header(pb, st);

  600. 

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

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

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

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

  605.                         break;

  606.                     }

  607. 

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

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

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

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

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

  613.                             return AVERROR(ENOMEM);

  614.                         }

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

  616.                     }

  617. 

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

  619.                         avio_r8(pb);

  620. 

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

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

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

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

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

  626.                         const uint8_t *pal_src;

  627. 

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

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

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

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

  632.                         ast->has_pal = 1;

  633.                     }

  634. 

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

  636. 

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

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

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

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

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

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

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

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

  645.                         st->codec->codec_id = CODEC_ID_RAWVIDEO;

  646. 

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

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

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

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

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

  652.                     }

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

  654. 

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

  656.                     break;

  657.                 case AVMEDIA_TYPE_AUDIO:

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

  659.                     if (ret < 0)

  660.                         return ret;

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

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

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

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

  665.                     }

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

  667.                         avio_skip(pb, 1);

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

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

  670.                     st->need_parsing = AVSTREAM_PARSE_TIMESTAMPS;

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

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

  673.                      * fail. */

  674.                     if (st->codec->codec_id == CODEC_ID_AAC && st->codec->extradata_size)

  675.                         st->need_parsing = AVSTREAM_PARSE_NONE;

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

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

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

  679.                         st->codec->codec_id  = CODEC_ID_XAN_DPCM;

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

  681.                         ast->dshow_block_align = 0;

  682.                     }

  683.                     if (amv_file_format){

  684.                         st->codec->codec_id  = CODEC_ID_ADPCM_IMA_AMV;

  685.                         ast->dshow_block_align = 0;

  686.                     }

  687.                     break;

  688.                 case AVMEDIA_TYPE_SUBTITLE:

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

  690.                     st->request_probe= 1;

  691.                     break;

  692.                 default:

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

  694.                     st->codec->codec_id= CODEC_ID_NONE;

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

  696.                     avio_skip(pb, size);

  697.                     break;

  698.                 }

  699.             }

  700.             break;

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

  702.             i= avio_tell(pb);

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

  704.                read_braindead_odml_indx(s, 0) < 0 && s->error_recognition >= FF_ER_EXPLODE){

  705.                 goto fail;            }

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

  707.             break;

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

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

  710.                 AVRational active, active_aspect;

  711. 

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

  713.                 avio_rl32(pb);

  714.                 avio_rl32(pb);

  715.                 avio_rl32(pb);

  716.                 avio_rl32(pb);

  717.                 avio_rl32(pb);

  718. 

  719.                 active_aspect.den= avio_rl16(pb);

  720.                 active_aspect.num= avio_rl16(pb);

  721.                 active.num       = avio_rl32(pb);

  722.                 active.den       = avio_rl32(pb);

  723.                 avio_rl32(pb); //nbFieldsPerFrame

  724. 

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

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

  727. //av_log(s, AV_LOG_ERROR, "vprp %d/%d %d/%d\n", active_aspect.num, active_aspect.den, active.num, active.den);

  728.                 }

  729.                 size -= 9*4;

  730.             }

  731.             avio_skip(pb, size);

  732.             break;

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

  734.             if(s->nb_streams){

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

  736.                 break;

  737.             }

  738.         default:

  739.             if(size > 1000000){

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

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

  742.                 if (s->error_recognition >= FF_ER_EXPLODE) goto fail;

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

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

  745.                 goto end_of_header;

  746.             }

  747.             /* skip tag */

  748.             size += (size & 1);

  749.             avio_skip(pb, size);

  750.             break;

  751.         }

  752.     }

  753.  end_of_header:

  754.     /* check stream number */

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

  756.     fail:

  757.         return -1;

  758.     }

  759. 

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

  761.         avi_load_index(s);

  762.     avi->index_loaded |= 1;

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

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

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

  766.         if(st->nb_index_entries)

  767.             break;

  768.     }

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

  770.     // a mis-detection.

  771.     if(avi->dv_demux)

  772.         avi->non_interleaved=0;

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

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

  775.         avi->non_interleaved=0;

  776.     }

  777. 

  778.     if(avi->non_interleaved) {

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

  780.         clean_index(s);

  781.     }

  782. 

  783.     ff_metadata_conv_ctx(s, NULL, avi_metadata_conv);

  784.     ff_metadata_conv_ctx(s, NULL, ff_riff_info_conv);

  785. 

  786.     return 0;

  787. }

  788. 

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

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

  791.         uint8_t desc[256];

  792.         int score = AVPROBE_SCORE_MAX / 2, ret;

  793.         AVIStream *ast = st->priv_data;

  794.         AVInputFormat *sub_demuxer;

  795.         AVRational time_base;

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

  797.                                               pkt->size - 7,

  798.                                               0, NULL, NULL, NULL, NULL);

  799.         AVProbeData pd;

  800.         unsigned int desc_len = avio_rl32(pb);

  801. 

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

  803.             goto error;

  804. 

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

  806.         avio_skip(pb, desc_len - ret);

  807.         if (*desc)

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

  809. 

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

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

  812. 

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

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

  815.             goto error;

  816. 

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

  818.             goto error;

  819. 

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

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

  822.             av_read_packet(ast->sub_ctx, &ast->sub_pkt);

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

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

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

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

  827.         }

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

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

  830.         return 1;

  831. error:

  832.         av_freep(&pb);

  833.     }

  834.     return 0;

  835. }

  836. 

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

  838.                                   AVPacket *pkt)

  839. {

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

  841.     int64_t ts, next_ts, ts_min = INT64_MAX;

  842.     AVStream *st, *sub_st = NULL;

  843.     int i;

  844. 

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

  846.                            AV_TIME_BASE_Q);

  847. 

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

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

  850.         ast = st->priv_data;

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

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

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

  854.                 ts_min = ts;

  855.                 sub_st = st;

  856.             }

  857.         }

  858.     }

  859. 

  860.     if (sub_st) {

  861.         ast = sub_st->priv_data;

  862.         *pkt = ast->sub_pkt;

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

  864.         if (av_read_packet(ast->sub_ctx, &ast->sub_pkt) < 0)

  865.             ast->sub_pkt.data = NULL;

  866.     }

  867.     return sub_st;

  868. }

  869. 

  870. static int get_stream_idx(int *d){

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

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

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

  874.     }else{

  875.         return 100; //invalid stream ID

  876.     }

  877. }

  878. 

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

  880. {

  881.     AVIContext *avi = s->priv_data;

  882.     AVIOContext *pb = s->pb;

  883.     int n;

  884.     unsigned int d[8];

  885.     unsigned int size;

  886.     int64_t i, sync;

  887. 

  888. start_sync:

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

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

  891.         int j;

  892. 

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

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

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

  896. 

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

  898. 

  899.         n= get_stream_idx(d+2);

  900. //av_log(s, AV_LOG_DEBUG, "%X %X %X %X %X %X %X %X %"PRId64" %d %d\n", d[0], d[1], d[2], d[3], d[4], d[5], d[6], d[7], i, size, n);

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

  902.             continue;

  903. 

  904.         //parse ix##

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

  906.         //parse JUNK

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

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

  909.             avio_skip(pb, size);

  910. //av_log(s, AV_LOG_DEBUG, "SKIP\n");

  911.             goto start_sync;

  912.         }

  913. 

  914.         //parse stray LIST

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

  916.             avio_skip(pb, 4);

  917.             goto start_sync;

  918.         }

  919. 

  920.         n= get_stream_idx(d);

  921. 

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

  923.             continue;

  924. 

  925.         //detect ##ix chunk and skip

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

  927.             avio_skip(pb, size);

  928.             goto start_sync;

  929.         }

  930. 

  931.         //parse ##dc/##wb

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

  933.             AVStream *st;

  934.             AVIStream *ast;

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

  936.             ast = st->priv_data;

  937. 

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

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

  940.                 AVIStream *ast1= st1->priv_data;

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

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

  943.                    && n==0

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

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

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

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

  948.                   ){

  949.                     n=1;

  950.                     st = st1;

  951.                     ast = ast1;

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

  953.                 }

  954.             }

  955. 

  956. 

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

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

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

  960.                 if (!exit_early) {

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

  962.                 }

  963.                 avio_skip(pb, size);

  964.                 goto start_sync;

  965.             }

  966. 

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

  968.                 int k = avio_r8(pb);

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

  970. 

  971.                 avio_rl16(pb); //flags

  972. 

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

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

  975.                 ast->has_pal= 1;

  976.                 goto start_sync;

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

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

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

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

  981. 

  982.                 if (exit_early)

  983.                     return 0;

  984. //av_log(s, AV_LOG_DEBUG, "OK\n");

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

  986.                     ast->prefix_count++;

  987.                 else{

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

  989.                     ast->prefix_count= 0;

  990.                 }

  991. 

  992.                 avi->stream_index= n;

  993.                 ast->packet_size= size + 8;

  994.                 ast->remaining= size;

  995. 

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

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

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

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

  1000.                     }

  1001.                 }

  1002.                 return 0;

  1003.             }

  1004.         }

  1005.     }

  1006. 

  1007.     if(pb->error)

  1008.         return pb->error;

  1009.     return AVERROR_EOF;

  1010. }

  1011. 

  1012. static int avi_read_packet(AVFormatContext *s, AVPacket *pkt)

  1013. {

  1014.     AVIContext *avi = s->priv_data;

  1015.     AVIOContext *pb = s->pb;

  1016.     int err;

  1017.     void* dstr;

  1018. 

  1019.     if (CONFIG_DV_DEMUXER && avi->dv_demux) {

  1020.         int size = avpriv_dv_get_packet(avi->dv_demux, pkt);

  1021.         if (size >= 0)

  1022.             return size;

  1023.     }

  1024. 

  1025.     if(avi->non_interleaved){

  1026.         int best_stream_index = 0;

  1027.         AVStream *best_st= NULL;

  1028.         AVIStream *best_ast;

  1029.         int64_t best_ts= INT64_MAX;

  1030.         int i;

  1031. 

  1032.         for(i=0; i<s->nb_streams; i++){

  1033.             AVStream *st = s->streams[i];

  1034.             AVIStream *ast = st->priv_data;

  1035.             int64_t ts= ast->frame_offset;

  1036.             int64_t last_ts;

  1037. 

  1038.             if(!st->nb_index_entries)

  1039.                 continue;

  1040. 

  1041.             last_ts = st->index_entries[st->nb_index_entries - 1].timestamp;

  1042.             if(!ast->remaining && ts > last_ts)

  1043.                 continue;

  1044. 

  1045.             ts = av_rescale_q(ts, st->time_base, (AVRational){FFMAX(1, ast->sample_size), AV_TIME_BASE});

  1046. 

  1047. //            av_log(s, AV_LOG_DEBUG, "%"PRId64" %d/%d %"PRId64"\n", ts, st->time_base.num, st->time_base.den, ast->frame_offset);

  1048.             if(ts < best_ts){

  1049.                 best_ts= ts;

  1050.                 best_st= st;

  1051.                 best_stream_index= i;

  1052.             }

  1053.         }

  1054.         if(!best_st)

  1055.             return AVERROR_EOF;

  1056. 

  1057.         best_ast = best_st->priv_data;

  1058.         best_ts = best_ast->frame_offset;

  1059.         if(best_ast->remaining)

  1060.             i= av_index_search_timestamp(best_st, best_ts, AVSEEK_FLAG_ANY | AVSEEK_FLAG_BACKWARD);

  1061.         else{

  1062.             i= av_index_search_timestamp(best_st, best_ts, AVSEEK_FLAG_ANY);

  1063.             if(i>=0)

  1064.                 best_ast->frame_offset= best_st->index_entries[i].timestamp;

  1065.         }

  1066. 

  1067. //        av_log(s, AV_LOG_DEBUG, "%d\n", i);

  1068.         if(i>=0){

  1069.             int64_t pos= best_st->index_entries[i].pos;

  1070.             pos += best_ast->packet_size - best_ast->remaining;

  1071.             if(avio_seek(s->pb, pos + 8, SEEK_SET) < 0)

  1072.               return AVERROR_EOF;

  1073. //        av_log(s, AV_LOG_DEBUG, "pos=%"PRId64"\n", pos);

  1074. 

  1075.             assert(best_ast->remaining <= best_ast->packet_size);

  1076. 

  1077.             avi->stream_index= best_stream_index;

  1078.             if(!best_ast->remaining)

  1079.                 best_ast->packet_size=

  1080.                 best_ast->remaining= best_st->index_entries[i].size;

  1081.         }

  1082.         else

  1083.           return AVERROR_EOF;

  1084.     }

  1085. 

  1086. resync:

  1087.     if(avi->stream_index >= 0){

  1088.         AVStream *st= s->streams[ avi->stream_index ];

  1089.         AVIStream *ast= st->priv_data;

  1090.         int size, err;

  1091. 

  1092.         if(get_subtitle_pkt(s, st, pkt))

  1093.             return 0;

  1094. 

  1095.         if(ast->sample_size <= 1) // minorityreport.AVI block_align=1024 sample_size=1 IMA-ADPCM

  1096.             size= INT_MAX;

  1097.         else if(ast->sample_size < 32)

  1098.             // arbitrary multiplier to avoid tiny packets for raw PCM data

  1099.             size= 1024*ast->sample_size;

  1100.         else

  1101.             size= ast->sample_size;

  1102. 

  1103.         if(size > ast->remaining)

  1104.             size= ast->remaining;

  1105.         avi->last_pkt_pos= avio_tell(pb);

  1106.         err= av_get_packet(pb, pkt, size);

  1107.         if(err<0)

  1108.             return err;

  1109. 

  1110.         if(ast->has_pal && pkt->data && pkt->size<(unsigned)INT_MAX/2){

  1111.             uint8_t *pal;

  1112.             pal = av_packet_new_side_data(pkt, AV_PKT_DATA_PALETTE, AVPALETTE_SIZE);

  1113.             if(!pal){

  1114.                 av_log(s, AV_LOG_ERROR, "Failed to allocate data for palette\n");

  1115.             }else{

  1116.                 memcpy(pal, ast->pal, AVPALETTE_SIZE);

  1117.                 ast->has_pal = 0;

  1118.             }

  1119.         }

  1120. 

  1121.         if (CONFIG_DV_DEMUXER && avi->dv_demux) {

  1122.             dstr = pkt->destruct;

  1123.             size = avpriv_dv_produce_packet(avi->dv_demux, pkt,

  1124.                                     pkt->data, pkt->size, pkt->pos);

  1125.             pkt->destruct = dstr;

  1126.             pkt->flags |= AV_PKT_FLAG_KEY;

  1127.             if (size < 0)

  1128.                 av_free_packet(pkt);

  1129.         } else if (st->codec->codec_type == AVMEDIA_TYPE_SUBTITLE

  1130.                    && !st->codec->codec_tag && read_gab2_sub(st, pkt)) {

  1131.             ast->frame_offset++;

  1132.             avi->stream_index = -1;

  1133.             ast->remaining = 0;

  1134.             goto resync;

  1135.         } else {

  1136.             /* XXX: How to handle B-frames in AVI? */

  1137.             pkt->dts = ast->frame_offset;

  1138. //                pkt->dts += ast->start;

  1139.             if(ast->sample_size)

  1140.                 pkt->dts /= ast->sample_size;

  1141. //av_log(s, AV_LOG_DEBUG, "dts:%"PRId64" offset:%"PRId64" %d/%d smpl_siz:%d base:%d st:%d size:%d\n", pkt->dts, ast->frame_offset, ast->scale, ast->rate, ast->sample_size, AV_TIME_BASE, avi->stream_index, size);

  1142.             pkt->stream_index = avi->stream_index;

  1143. 

  1144.             if (st->codec->codec_type == AVMEDIA_TYPE_VIDEO) {

  1145.                 AVIndexEntry *e;

  1146.                 int index;

  1147.                 assert(st->index_entries);

  1148. 

  1149.                 index= av_index_search_timestamp(st, ast->frame_offset, 0);

  1150.                 e= &st->index_entries[index];

  1151. 

  1152.                 if(index >= 0 && e->timestamp == ast->frame_offset){

  1153.                     if (index == st->nb_index_entries-1){

  1154.                         int key=1;

  1155.                         int i;

  1156.                         uint32_t state=-1;

  1157.                         for(i=0; i<FFMIN(size,256); i++){

  1158.                             if(st->codec->codec_id == CODEC_ID_MPEG4){

  1159.                                 if(state == 0x1B6){

  1160.                                     key= !(pkt->data[i]&0xC0);

  1161.                                     break;

  1162.                                 }

  1163.                             }else

  1164.                                 break;

  1165.                             state= (state<<8) + pkt->data[i];

  1166.                         }

  1167.                         if(!key)

  1168.                             e->flags &= ~AVINDEX_KEYFRAME;

  1169.                     }

  1170.                     if (e->flags & AVINDEX_KEYFRAME)

  1171.                         pkt->flags |= AV_PKT_FLAG_KEY;

  1172.                 }

  1173.             } else {

  1174.                 pkt->flags |= AV_PKT_FLAG_KEY;

  1175.             }

  1176.             ast->frame_offset += get_duration(ast, pkt->size);

  1177.         }

  1178.         ast->remaining -= size;

  1179.         if(!ast->remaining){

  1180.             avi->stream_index= -1;

  1181.             ast->packet_size= 0;

  1182.         }

  1183. 

  1184.         if(!avi->non_interleaved && pkt->pos >= 0 && ast->seek_pos > pkt->pos){

  1185.             av_free_packet(pkt);

  1186.             goto resync;

  1187.         }

  1188.         ast->seek_pos= 0;

  1189. 

  1190.         if(!avi->non_interleaved && st->nb_index_entries>1 && avi->index_loaded>1){

  1191.             int64_t dts= av_rescale_q(pkt->dts, st->time_base, AV_TIME_BASE_Q);

  1192. 

  1193.             if(avi->dts_max - dts > 2*AV_TIME_BASE){

  1194.                 avi->non_interleaved= 1;

  1195.                 av_log(s, AV_LOG_INFO, "Switching to NI mode, due to poor interleaving\n");

  1196.             }else if(avi->dts_max < dts)

  1197.                 avi->dts_max = dts;

  1198.         }

  1199. 

  1200.         return size;

  1201.     }

  1202. 

  1203.     if ((err = avi_sync(s, 0)) < 0)

  1204.         return err;

  1205.     goto resync;

  1206. }

  1207. 

  1208. /* XXX: We make the implicit supposition that the positions are sorted

  1209.    for each stream. */

  1210. static int avi_read_idx1(AVFormatContext *s, int size)

  1211. {

  1212.     AVIContext *avi = s->priv_data;

  1213.     AVIOContext *pb = s->pb;

  1214.     int nb_index_entries, i;

  1215.     AVStream *st;

  1216.     AVIStream *ast;

  1217.     unsigned int index, tag, flags, pos, len, first_packet = 1;

  1218.     unsigned last_pos= -1;

  1219.     int64_t idx1_pos, first_packet_pos = 0, data_offset = 0;

  1220. 

  1221.     nb_index_entries = size / 16;

  1222.     if (nb_index_entries <= 0)

  1223.         return -1;

  1224. 

  1225.     idx1_pos = avio_tell(pb);

  1226.     avio_seek(pb, avi->movi_list+4, SEEK_SET);

  1227.     if (avi_sync(s, 1) == 0) {

  1228.         first_packet_pos = avio_tell(pb) - 8;

  1229.     }

  1230.     avi->stream_index = -1;

  1231.     avio_seek(pb, idx1_pos, SEEK_SET);

  1232. 

  1233.     /* Read the entries and sort them in each stream component. */

  1234.     for(i = 0; i < nb_index_entries; i++) {

  1235.         if(url_feof(pb))

  1236.             return -1;

  1237. 

  1238.         tag = avio_rl32(pb);

  1239.         flags = avio_rl32(pb);

  1240.         pos = avio_rl32(pb);

  1241.         len = avio_rl32(pb);

  1242.         av_dlog(s, "%d: tag=0x%x flags=0x%x pos=0x%x len=%d/",

  1243.                 i, tag, flags, pos, len);

  1244. 

  1245.         index = ((tag & 0xff) - '0') * 10;

  1246.         index += ((tag >> 8) & 0xff) - '0';

  1247.         if (index >= s->nb_streams)

  1248.             continue;

  1249.         st = s->streams[index];

  1250.         ast = st->priv_data;

  1251. 

  1252.         if(first_packet && first_packet_pos && len) {

  1253.             data_offset = first_packet_pos - pos;

  1254.             first_packet = 0;

  1255.         }

  1256.         pos += data_offset;

  1257. 

  1258.         av_dlog(s, "%d cum_len=%"PRId64"\n", len, ast->cum_len);

  1259. 

  1260. 

  1261.         if(last_pos == pos)

  1262.             avi->non_interleaved= 1;

  1263.         else if(len || !ast->sample_size)

  1264.             av_add_index_entry(st, pos, ast->cum_len, len, 0, (flags&AVIIF_INDEX) ? AVINDEX_KEYFRAME : 0);

  1265.         ast->cum_len += get_duration(ast, len);

  1266.         last_pos= pos;

  1267.     }

  1268.     return 0;

  1269. }

  1270. 

  1271. static int guess_ni_flag(AVFormatContext *s){

  1272.     int i;

  1273.     int64_t last_start=0;

  1274.     int64_t first_end= INT64_MAX;

  1275.     int64_t oldpos= avio_tell(s->pb);

  1276. 

  1277.     for(i=0; i<s->nb_streams; i++){

  1278.         AVStream *st = s->streams[i];

  1279.         int n= st->nb_index_entries;

  1280.         unsigned int size;

  1281. 

  1282.         if(n <= 0)

  1283.             continue;

  1284. 

  1285.         if(n >= 2){

  1286.             int64_t pos= st->index_entries[0].pos;

  1287.             avio_seek(s->pb, pos + 4, SEEK_SET);

  1288.             size= avio_rl32(s->pb);

  1289.             if(pos + size > st->index_entries[1].pos)

  1290.                 last_start= INT64_MAX;

  1291.         }

  1292. 

  1293.         if(st->index_entries[0].pos > last_start)

  1294.             last_start= st->index_entries[0].pos;

  1295.         if(st->index_entries[n-1].pos < first_end)

  1296.             first_end= st->index_entries[n-1].pos;

  1297.     }

  1298.     avio_seek(s->pb, oldpos, SEEK_SET);

  1299.     return last_start > first_end;

  1300. }

  1301. 

  1302. static int avi_load_index(AVFormatContext *s)

  1303. {

  1304.     AVIContext *avi = s->priv_data;

  1305.     AVIOContext *pb = s->pb;

  1306.     uint32_t tag, size;

  1307.     int64_t pos= avio_tell(pb);

  1308.     int ret = -1;

  1309. 

  1310.     if (avio_seek(pb, avi->movi_end, SEEK_SET) < 0)

  1311.         goto the_end; // maybe truncated file

  1312.     av_dlog(s, "movi_end=0x%"PRIx64"\n", avi->movi_end);

  1313.     for(;;) {

  1314.         if (url_feof(pb))

  1315.             break;

  1316.         tag = avio_rl32(pb);

  1317.         size = avio_rl32(pb);

  1318.         av_dlog(s, "tag=%c%c%c%c size=0x%x\n",

  1319.                  tag        & 0xff,

  1320.                 (tag >>  8) & 0xff,

  1321.                 (tag >> 16) & 0xff,

  1322.                 (tag >> 24) & 0xff,

  1323.                 size);

  1324. 

  1325.         if (tag == MKTAG('i', 'd', 'x', '1') &&

  1326.             avi_read_idx1(s, size) >= 0) {

  1327.             avi->index_loaded=2;

  1328.             ret = 0;

  1329.             break;

  1330.         }

  1331. 

  1332.         size += (size & 1);

  1333.         if (avio_skip(pb, size) < 0)

  1334.             break; // something is wrong here

  1335.     }

  1336.  the_end:

  1337.     avio_seek(pb, pos, SEEK_SET);

  1338.     return ret;

  1339. }

  1340. 

  1341. static void seek_subtitle(AVStream *st, AVStream *st2, int64_t timestamp)

  1342. {

  1343.     AVIStream *ast2 = st2->priv_data;

  1344.     int64_t ts2 = av_rescale_q(timestamp, st->time_base, st2->time_base);

  1345.     av_free_packet(&ast2->sub_pkt);

  1346.     if (avformat_seek_file(ast2->sub_ctx, 0, INT64_MIN, ts2, ts2, 0) >= 0 ||

  1347.         avformat_seek_file(ast2->sub_ctx, 0, ts2, ts2, INT64_MAX, 0) >= 0)

  1348.         av_read_packet(ast2->sub_ctx, &ast2->sub_pkt);

  1349. }

  1350. 

  1351. static int avi_read_seek(AVFormatContext *s, int stream_index, int64_t timestamp, int flags)

  1352. {

  1353.     AVIContext *avi = s->priv_data;

  1354.     AVStream *st;

  1355.     int i, index;

  1356.     int64_t pos, pos_min;

  1357.     AVIStream *ast;

  1358. 

  1359.     if (!avi->index_loaded) {

  1360.         /* we only load the index on demand */

  1361.         avi_load_index(s);

  1362.         avi->index_loaded |= 1;

  1363.     }

  1364.     assert(stream_index>= 0);

  1365. 

  1366.     st = s->streams[stream_index];

  1367.     ast= st->priv_data;

  1368.     index= av_index_search_timestamp(st, timestamp * FFMAX(ast->sample_size, 1), flags);

  1369.     if(index<0)

  1370.         return -1;

  1371. 

  1372.     /* find the position */

  1373.     pos = st->index_entries[index].pos;

  1374.     timestamp = st->index_entries[index].timestamp / FFMAX(ast->sample_size, 1);

  1375. 

  1376. //    av_log(s, AV_LOG_DEBUG, "XX %"PRId64" %d %"PRId64"\n", timestamp, index, st->index_entries[index].timestamp);

  1377. 

  1378.     if (CONFIG_DV_DEMUXER && avi->dv_demux) {

  1379.         /* One and only one real stream for DV in AVI, and it has video  */

  1380.         /* offsets. Calling with other stream indexes should have failed */

  1381.         /* the av_index_search_timestamp call above.                     */

  1382.         assert(stream_index == 0);

  1383. 

  1384.         if(avio_seek(s->pb, pos, SEEK_SET) < 0)

  1385.             return -1;

  1386. 

  1387.         /* Feed the DV video stream version of the timestamp to the */

  1388.         /* DV demux so it can synthesize correct timestamps.        */

  1389.         dv_offset_reset(avi->dv_demux, timestamp);

  1390. 

  1391.         avi->stream_index= -1;

  1392.         return 0;

  1393.     }

  1394. 

  1395.     pos_min= pos;

  1396.     for(i = 0; i < s->nb_streams; i++) {

  1397.         AVStream *st2 = s->streams[i];

  1398.         AVIStream *ast2 = st2->priv_data;

  1399. 

  1400.         ast2->packet_size=

  1401.         ast2->remaining= 0;

  1402. 

  1403.         if (ast2->sub_ctx) {

  1404.             seek_subtitle(st, st2, timestamp);

  1405.             continue;

  1406.         }

  1407. 

  1408.         if (st2->nb_index_entries <= 0)

  1409.             continue;

  1410. 

  1411. //        assert(st2->codec->block_align);

  1412.         assert((int64_t)st2->time_base.num*ast2->rate == (int64_t)st2->time_base.den*ast2->scale);

  1413.         index = av_index_search_timestamp(

  1414.                 st2,

  1415.                 av_rescale_q(timestamp, st->time_base, st2->time_base) * FFMAX(ast2->sample_size, 1),

  1416.                 flags | AVSEEK_FLAG_BACKWARD | (st2->codec->codec_type != AVMEDIA_TYPE_VIDEO ? AVSEEK_FLAG_ANY : 0));

  1417.         if(index<0)

  1418.             index=0;

  1419.         ast2->seek_pos= st2->index_entries[index].pos;

  1420.         pos_min= FFMIN(pos_min,ast2->seek_pos);

  1421.     }

  1422.     for(i = 0; i < s->nb_streams; i++) {

  1423.         AVStream *st2 = s->streams[i];

  1424.         AVIStream *ast2 = st2->priv_data;

  1425. 

  1426.         if (ast2->sub_ctx || st2->nb_index_entries <= 0)

  1427.             continue;

  1428. 

  1429.         index = av_index_search_timestamp(

  1430.                 st2,

  1431.                 av_rescale_q(timestamp, st->time_base, st2->time_base) * FFMAX(ast2->sample_size, 1),

  1432.                 flags | AVSEEK_FLAG_BACKWARD | (st2->codec->codec_type != AVMEDIA_TYPE_VIDEO ? AVSEEK_FLAG_ANY : 0));

  1433.         if(index<0)

  1434.             index=0;

  1435.         while(!avi->non_interleaved && index>0 && st2->index_entries[index-1].pos >= pos_min)

  1436.             index--;

  1437.         ast2->frame_offset = st2->index_entries[index].timestamp;

  1438.     }

  1439. 

  1440.     /* do the seek */

  1441.     if (avio_seek(s->pb, pos_min, SEEK_SET) < 0)

  1442.         return -1;

  1443.     avi->stream_index= -1;

  1444.     avi->dts_max= INT_MIN;

  1445.     return 0;

  1446. }

  1447. 

  1448. static int avi_read_close(AVFormatContext *s)

  1449. {

  1450.     int i;

  1451.     AVIContext *avi = s->priv_data;

  1452. 

  1453.     for(i=0;i<s->nb_streams;i++) {

  1454.         AVStream *st = s->streams[i];

  1455.         AVIStream *ast = st->priv_data;

  1456.         if (ast) {

  1457.             if (ast->sub_ctx) {

  1458.                 av_freep(&ast->sub_ctx->pb);

  1459.                 avformat_close_input(&ast->sub_ctx);

  1460.             }

  1461.             av_free(ast->sub_buffer);

  1462.             av_free_packet(&ast->sub_pkt);

  1463.         }

  1464.     }

  1465. 

  1466.     av_free(avi->dv_demux);

  1467. 

  1468.     return 0;

  1469. }

  1470. 

  1471. static int avi_probe(AVProbeData *p)

  1472. {

  1473.     int i;

  1474. 

  1475.     /* check file header */

  1476.     for(i=0; avi_headers[i][0]; i++)

  1477.         if(!memcmp(p->buf  , avi_headers[i]  , 4) &&

  1478.            !memcmp(p->buf+8, avi_headers[i]+4, 4))

  1479.             return AVPROBE_SCORE_MAX;

  1480. 

  1481.     return 0;

  1482. }

  1483. 

  1484. AVInputFormat ff_avi_demuxer = {

  1485.     .name           = "avi",

  1486.     .long_name      = NULL_IF_CONFIG_SMALL("AVI format"),

  1487.     .priv_data_size = sizeof(AVIContext),

  1488.     .read_probe     = avi_probe,

  1489.     .read_header    = avi_read_header,

  1490.     .read_packet    = avi_read_packet,

  1491.     .read_close     = avi_read_close,

  1492.     .read_seek      = avi_read_seek,

  1493.     .priv_class = &demuxer_class,

  1494. };