libavformat/avidec.c

   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/bswap.h"
  24 #include "avformat.h"
  25 #include "avi.h"
  26 #include "dv.h"
  27 #include "riff.h"
  28
  29 #undef NDEBUG
  30 #include <assert.h>
  31
  32 //#define DEBUG
  33 //#define DEBUG_SEEK
  34
  35 typedef struct AVIStream {
  36     int64_t frame_offset; /* current frame (video) or byte (audio) counter
  37                          (used to compute the pts) */
  38     int remaining;
  39     int packet_size;
  40
  41     int scale;
  42     int rate;
  43     int sample_size; /* size of one sample (or packet) (in the rate/scale sense) in bytes */
  44
  45     int64_t cum_len; /* temporary storage (used during seek) */
  46
  47     int prefix;                       ///< normally 'd'<<8 + 'c' or 'w'<<8 + 'b'
  48     int prefix_count;
  49     uint32_t pal[256];
  50     int has_pal;
  51 } AVIStream;
  52
  53 typedef struct {
  54     int64_t  riff_end;
  55     int64_t  movi_end;
  56     int64_t  fsize;
  57     int64_t movi_list;
  58     int64_t last_pkt_pos;
  59     int index_loaded;
  60     int is_odml;
  61     int non_interleaved;
  62     int stream_index;
  63     DVDemuxContext* dv_demux;
  64 } AVIContext;
  65
  66 static const char avi_headers[][8] = {
  67     { 'R', 'I', 'F', 'F',    'A', 'V', 'I', ' ' },
  68     { 'R', 'I', 'F', 'F',    'A', 'V', 'I', 'X' },
  69     { 'R', 'I', 'F', 'F',    'A', 'V', 'I', 0x19},
  70     { 'O', 'N', '2', ' ',    'O', 'N', '2', 'f' },
  71     { 'R', 'I', 'F', 'F',    'A', 'M', 'V', ' ' },
  72     { 0 }
  73 };
  74
  75 static int avi_load_index(AVFormatContext *s);
  76 static int guess_ni_flag(AVFormatContext *s);
  77
  78 #ifdef DEBUG
  79 static void print_tag(const char *str, unsigned int tag, int size)
  80 {
  81     printf("%s: tag=%c%c%c%c size=0x%x\n",
  82            str, tag & 0xff,
  83            (tag >> 8) & 0xff,
  84            (tag >> 16) & 0xff,
  85            (tag >> 24) & 0xff,
  86            size);
  87 }
  88 #endif
  89
  90 static int get_riff(AVFormatContext *s, ByteIOContext *pb)
  91 {
  92     AVIContext *avi = s->priv_data;
  93     char header[8];
  94     int i;
  95
  96     /* check RIFF header */
  97     get_buffer(pb, header, 4);
  98     avi->riff_end = get_le32(pb);   /* RIFF chunk size */
  99     avi->riff_end += url_ftell(pb); /* RIFF chunk end */
 100     get_buffer(pb, header+4, 4);
 101
 102     for(i=0; avi_headers[i][0]; i++)
 103         if(!memcmp(header, avi_headers[i], 8))
 104             break;
 105     if(!avi_headers[i][0])
 106         return -1;
 107
 108     if(header[7] == 0x19)
 109         av_log(s, AV_LOG_INFO, "This file has been generated by a totally broken muxer.\n");
 110
 111     return 0;
 112 }
 113
 114 static int read_braindead_odml_indx(AVFormatContext *s, int frame_num){
 115     AVIContext *avi = s->priv_data;
 116     ByteIOContext *pb = s->pb;
 117     int longs_pre_entry= get_le16(pb);
 118     int index_sub_type = get_byte(pb);
 119     int index_type     = get_byte(pb);
 120     int entries_in_use = get_le32(pb);
 121     int chunk_id       = get_le32(pb);
 122     int64_t base       = get_le64(pb);
 123     int stream_id= 10*((chunk_id&0xFF) - '0') + (((chunk_id>>8)&0xFF) - '0');
 124     AVStream *st;
 125     AVIStream *ast;
 126     int i;
 127     int64_t last_pos= -1;
 128     int64_t filesize= url_fsize(s->pb);
 129
 130 #ifdef DEBUG_SEEK
 131     av_log(s, AV_LOG_ERROR, "longs_pre_entry:%d index_type:%d entries_in_use:%d chunk_id:%X base:%16"PRIX64"\n",
 132         longs_pre_entry,index_type, entries_in_use, chunk_id, base);
 133 #endif
 134
 135     if(stream_id > s->nb_streams || stream_id < 0)
 136         return -1;
 137     st= s->streams[stream_id];
 138     ast = st->priv_data;
 139
 140     if(index_sub_type)
 141         return -1;
 142
 143     get_le32(pb);
 144
 145     if(index_type && longs_pre_entry != 2)
 146         return -1;
 147     if(index_type>1)
 148         return -1;
 149
 150     if(filesize > 0 && base >= filesize){
 151         av_log(s, AV_LOG_ERROR, "ODML index invalid\n");
 152         if(base>>32 == (base & 0xFFFFFFFF) && (base & 0xFFFFFFFF) < filesize && filesize <= 0xFFFFFFFF)
 153             base &= 0xFFFFFFFF;
 154         else
 155             return -1;
 156     }
 157
 158     for(i=0; i<entries_in_use; i++){
 159         if(index_type){
 160             int64_t pos= get_le32(pb) + base - 8;
 161             int len    = get_le32(pb);
 162             int key= len >= 0;
 163             len &= 0x7FFFFFFF;
 164
 165 #ifdef DEBUG_SEEK
 166             av_log(s, AV_LOG_ERROR, "pos:%"PRId64", len:%X\n", pos, len);
 167 #endif
 168             if(url_feof(pb))
 169                 return -1;
 170
 171             if(last_pos == pos || pos == base - 8)
 172                 avi->non_interleaved= 1;
 173             if(last_pos != pos)
 174                 av_add_index_entry(st, pos, ast->cum_len / FFMAX(1, ast->sample_size), len, 0, key ? AVINDEX_KEYFRAME : 0);
 175
 176             if(ast->sample_size)
 177                 ast->cum_len += len;
 178             else
 179                 ast->cum_len ++;
 180             last_pos= pos;
 181         }else{
 182             int64_t offset, pos;
 183             int duration;
 184             offset = get_le64(pb);
 185             get_le32(pb);       /* size */
 186             duration = get_le32(pb);
 187
 188             if(url_feof(pb))
 189                 return -1;
 190
 191             pos = url_ftell(pb);
 192
 193             url_fseek(pb, offset+8, SEEK_SET);
 194             read_braindead_odml_indx(s, frame_num);
 195             frame_num += duration;
 196
 197             url_fseek(pb, pos, SEEK_SET);
 198         }
 199     }
 200     avi->index_loaded=1;
 201     return 0;
 202 }
 203
 204 static void clean_index(AVFormatContext *s){
 205     int i;
 206     int64_t j;
 207
 208     for(i=0; i<s->nb_streams; i++){
 209         AVStream *st = s->streams[i];
 210         AVIStream *ast = st->priv_data;
 211         int n= st->nb_index_entries;
 212         int max= ast->sample_size;
 213         int64_t pos, size, ts;
 214
 215         if(n != 1 || ast->sample_size==0)
 216             continue;
 217
 218         while(max < 1024) max+=max;
 219
 220         pos= st->index_entries[0].pos;
 221         size= st->index_entries[0].size;
 222         ts= st->index_entries[0].timestamp;
 223
 224         for(j=0; j<size; j+=max){
 225             av_add_index_entry(st, pos+j, ts + j/ast->sample_size, FFMIN(max, size-j), 0, AVINDEX_KEYFRAME);
 226         }
 227     }
 228 }
 229
 230 static int avi_read_tag(AVFormatContext *s, const char *key, unsigned int size)
 231 {
 232     ByteIOContext *pb = s->pb;
 233     uint8_t value[1024];
 234
 235     int64_t i = url_ftell(pb);
 236     size += (size & 1);
 237     get_strz(pb, value, sizeof(value));
 238     url_fseek(pb, i+size, SEEK_SET);
 239
 240     return av_metadata_set(&s->metadata, key, value);
 241 }
 242
 243 static int avi_read_header(AVFormatContext *s, AVFormatParameters *ap)
 244 {
 245     AVIContext *avi = s->priv_data;
 246     ByteIOContext *pb = s->pb;
 247     unsigned int tag, tag1, handler;
 248     int codec_type, stream_index, frame_period, bit_rate;
 249     unsigned int size, nb_frames;
 250     int i;
 251     AVStream *st;
 252     AVIStream *ast = NULL;
 253     int avih_width=0, avih_height=0;
 254     int amv_file_format=0;
 255
 256     avi->stream_index= -1;
 257
 258     if (get_riff(s, pb) < 0)
 259         return -1;
 260
 261     avi->fsize = url_fsize(pb);
 262     if(avi->fsize<=0)
 263         avi->fsize= avi->riff_end == 8 ? INT64_MAX : avi->riff_end;
 264
 265     /* first list tag */
 266     stream_index = -1;
 267     codec_type = -1;
 268     frame_period = 0;
 269     for(;;) {
 270         if (url_feof(pb))
 271             goto fail;
 272         tag = get_le32(pb);
 273         size = get_le32(pb);
 274 #ifdef DEBUG
 275         print_tag("tag", tag, size);
 276 #endif
 277
 278         switch(tag) {
 279         case MKTAG('L', 'I', 'S', 'T'):
 280             /* Ignored, except at start of video packets. */
 281             tag1 = get_le32(pb);
 282 #ifdef DEBUG
 283             print_tag("list", tag1, 0);
 284 #endif
 285             if (tag1 == MKTAG('m', 'o', 'v', 'i')) {
 286                 avi->movi_list = url_ftell(pb) - 4;
 287                 if(size) avi->movi_end = avi->movi_list + size + (size & 1);
 288                 else     avi->movi_end = url_fsize(pb);
 289 #ifdef DEBUG
 290                 printf("movi end=%"PRIx64"\n", avi->movi_end);
 291 #endif
 292                 goto end_of_header;
 293             }
 294             break;
 295         case MKTAG('d', 'm', 'l', 'h'):
 296             avi->is_odml = 1;
 297             url_fskip(pb, size + (size & 1));
 298             break;
 299         case MKTAG('a', 'm', 'v', 'h'):
 300             amv_file_format=1;
 301         case MKTAG('a', 'v', 'i', 'h'):
 302             /* AVI header */
 303             /* using frame_period is bad idea */
 304             frame_period = get_le32(pb);
 305             bit_rate = get_le32(pb) * 8;
 306             get_le32(pb);
 307             avi->non_interleaved |= get_le32(pb) & AVIF_MUSTUSEINDEX;
 308
 309             url_fskip(pb, 2 * 4);
 310             get_le32(pb);
 311             get_le32(pb);
 312             avih_width=get_le32(pb);
 313             avih_height=get_le32(pb);
 314
 315             url_fskip(pb, size - 10 * 4);
 316             break;
 317         case MKTAG('s', 't', 'r', 'h'):
 318             /* stream header */
 319
 320             tag1 = get_le32(pb);
 321             handler = get_le32(pb); /* codec tag */
 322
 323             if(tag1 == MKTAG('p', 'a', 'd', 's')){
 324                 url_fskip(pb, size - 8);
 325                 break;
 326             }else{
 327                 stream_index++;
 328                 st = av_new_stream(s, stream_index);
 329                 if (!st)
 330                     goto fail;
 331
 332                 ast = av_mallocz(sizeof(AVIStream));
 333                 if (!ast)
 334                     goto fail;
 335                 st->priv_data = ast;
 336             }
 337             if(amv_file_format)
 338                 tag1 = stream_index ? MKTAG('a','u','d','s') : MKTAG('v','i','d','s');
 339
 340 #ifdef DEBUG
 341             print_tag("strh", tag1, -1);
 342 #endif
 343             if(tag1 == MKTAG('i', 'a', 'v', 's') || tag1 == MKTAG('i', 'v', 'a', 's')){
 344                 int64_t dv_dur;
 345
 346                 /*
 347                  * After some consideration -- I don't think we
 348                  * have to support anything but DV in type1 AVIs.
 349                  */
 350                 if (s->nb_streams != 1)
 351                     goto fail;
 352
 353                 if (handler != MKTAG('d', 'v', 's', 'd') &&
 354                     handler != MKTAG('d', 'v', 'h', 'd') &&
 355                     handler != MKTAG('d', 'v', 's', 'l'))
 356                    goto fail;
 357
 358                 ast = s->streams[0]->priv_data;
 359                 av_freep(&s->streams[0]->codec->extradata);
 360                 av_freep(&s->streams[0]);
 361                 s->nb_streams = 0;
 362                 if (CONFIG_DV_DEMUXER) {
 363                     avi->dv_demux = dv_init_demux(s);
 364                     if (!avi->dv_demux)
 365                         goto fail;
 366                 }
 367                 s->streams[0]->priv_data = ast;
 368                 url_fskip(pb, 3 * 4);
 369                 ast->scale = get_le32(pb);
 370                 ast->rate = get_le32(pb);
 371                 url_fskip(pb, 4);  /* start time */
 372
 373                 dv_dur = get_le32(pb);
 374                 if (ast->scale > 0 && ast->rate > 0 && dv_dur > 0) {
 375                     dv_dur *= AV_TIME_BASE;
 376                     s->duration = av_rescale(dv_dur, ast->scale, ast->rate);
 377                 }
 378                 /*
 379                  * else, leave duration alone; timing estimation in utils.c
 380                  *      will make a guess based on bitrate.
 381                  */
 382
 383                 stream_index = s->nb_streams - 1;
 384                 url_fskip(pb, size - 9*4);
 385                 break;
 386             }
 387
 388             assert(stream_index < s->nb_streams);
 389             st->codec->stream_codec_tag= handler;
 390
 391             get_le32(pb); /* flags */
 392             get_le16(pb); /* priority */
 393             get_le16(pb); /* language */
 394             get_le32(pb); /* initial frame */
 395             ast->scale = get_le32(pb);
 396             ast->rate = get_le32(pb);
 397             if(!(ast->scale && ast->rate)){
 398                 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);
 399                 if(frame_period){
 400                     ast->rate = 1000000;
 401                     ast->scale = frame_period;
 402                 }else{
 403                     ast->rate = 25;
 404                     ast->scale = 1;
 405                 }
 406             }
 407             av_set_pts_info(st, 64, ast->scale, ast->rate);
 408
 409             ast->cum_len=get_le32(pb); /* start */
 410             nb_frames = get_le32(pb);
 411
 412             st->start_time = 0;
 413             st->duration = nb_frames;
 414             get_le32(pb); /* buffer size */
 415             get_le32(pb); /* quality */
 416             ast->sample_size = get_le32(pb); /* sample ssize */
 417             ast->cum_len *= FFMAX(1, ast->sample_size);
 418 //            av_log(s, AV_LOG_DEBUG, "%d %d %d %d\n", ast->rate, ast->scale, ast->start, ast->sample_size);
 419
 420             switch(tag1) {
 421             case MKTAG('v', 'i', 'd', 's'):
 422                 codec_type = CODEC_TYPE_VIDEO;
 423
 424                 ast->sample_size = 0;
 425                 break;
 426             case MKTAG('a', 'u', 'd', 's'):
 427                 codec_type = CODEC_TYPE_AUDIO;
 428                 break;
 429             case MKTAG('t', 'x', 't', 's'):
 430                 //FIXME
 431                 codec_type = CODEC_TYPE_DATA; //CODEC_TYPE_SUB ?  FIXME
 432                 break;
 433             case MKTAG('d', 'a', 't', 's'):
 434                 codec_type = CODEC_TYPE_DATA;
 435                 break;
 436             default:
 437                 av_log(s, AV_LOG_ERROR, "unknown stream type %X\n", tag1);
 438                 goto fail;
 439             }
 440             ast->frame_offset= ast->cum_len;
 441             url_fskip(pb, size - 12 * 4);
 442             break;
 443         case MKTAG('s', 't', 'r', 'f'):
 444             /* stream header */
 445             if (stream_index >= (unsigned)s->nb_streams || avi->dv_demux) {
 446                 url_fskip(pb, size);
 447             } else {
 448                 st = s->streams[stream_index];
 449                 switch(codec_type) {
 450                 case CODEC_TYPE_VIDEO:
 451                     if(amv_file_format){
 452                         st->codec->width=avih_width;
 453                         st->codec->height=avih_height;
 454                         st->codec->codec_type = CODEC_TYPE_VIDEO;
 455                         st->codec->codec_id = CODEC_ID_AMV;
 456                         url_fskip(pb, size);
 457                         break;
 458                     }
 459                     get_le32(pb); /* size */
 460                     st->codec->width = get_le32(pb);
 461                     st->codec->height = (int32_t)get_le32(pb);
 462                     get_le16(pb); /* panes */
 463                     st->codec->bits_per_coded_sample= get_le16(pb); /* depth */
 464                     tag1 = get_le32(pb);
 465                     get_le32(pb); /* ImageSize */
 466                     get_le32(pb); /* XPelsPerMeter */
 467                     get_le32(pb); /* YPelsPerMeter */
 468                     get_le32(pb); /* ClrUsed */
 469                     get_le32(pb); /* ClrImportant */
 470
 471                     if (tag1 == MKTAG('D', 'X', 'S', 'B')) {
 472                         st->codec->codec_type = CODEC_TYPE_SUBTITLE;
 473                         st->codec->codec_tag = tag1;
 474                         st->codec->codec_id = CODEC_ID_XSUB;
 475                         break;
 476                     }
 477
 478                     if(size > 10*4 && size<(1<<30)){
 479                         st->codec->extradata_size= size - 10*4;
 480                         st->codec->extradata= av_malloc(st->codec->extradata_size + FF_INPUT_BUFFER_PADDING_SIZE);
 481                         get_buffer(pb, st->codec->extradata, st->codec->extradata_size);
 482                     }
 483
 484                     if(st->codec->extradata_size & 1) //FIXME check if the encoder really did this correctly
 485                         get_byte(pb);
 486
 487                     /* Extract palette from extradata if bpp <= 8. */
 488                     /* This code assumes that extradata contains only palette. */
 489                     /* This is true for all paletted codecs implemented in FFmpeg. */
 490                     if (st->codec->extradata_size && (st->codec->bits_per_coded_sample <= 8)) {
 491                         st->codec->palctrl = av_mallocz(sizeof(AVPaletteControl));
 492 #ifdef WORDS_BIGENDIAN
 493                         for (i = 0; i < FFMIN(st->codec->extradata_size, AVPALETTE_SIZE)/4; i++)
 494                             st->codec->palctrl->palette[i] = bswap_32(((uint32_t*)st->codec->extradata)[i]);
 495 #else
 496                         memcpy(st->codec->palctrl->palette, st->codec->extradata,
 497                                FFMIN(st->codec->extradata_size, AVPALETTE_SIZE));
 498 #endif
 499                         st->codec->palctrl->palette_changed = 1;
 500                     }
 501
 502 #ifdef DEBUG
 503                     print_tag("video", tag1, 0);
 504 #endif
 505                     st->codec->codec_type = CODEC_TYPE_VIDEO;
 506                     st->codec->codec_tag = tag1;
 507                     st->codec->codec_id = codec_get_id(codec_bmp_tags, tag1);
 508                     st->need_parsing = AVSTREAM_PARSE_HEADERS; // This is needed to get the pict type which is necessary for generating correct pts.
 509
 510                     if(st->codec->codec_tag==0 && st->codec->height > 0 && st->codec->extradata_size < 1U<<30){
 511                         st->codec->extradata_size+= 9;
 512                         st->codec->extradata= av_realloc(st->codec->extradata, st->codec->extradata_size + FF_INPUT_BUFFER_PADDING_SIZE);
 513                         if(st->codec->extradata)
 514                             memcpy(st->codec->extradata + st->codec->extradata_size - 9, "BottomUp", 9);
 515                     }
 516                     st->codec->height= FFABS(st->codec->height);
 517
 518 //                    url_fskip(pb, size - 5 * 4);
 519                     break;
 520                 case CODEC_TYPE_AUDIO:
 521                     get_wav_header(pb, st->codec, size);
 522                     if(ast->sample_size && st->codec->block_align && ast->sample_size != st->codec->block_align){
 523                         av_log(s, AV_LOG_WARNING, "sample size (%d) != block align (%d)\n", ast->sample_size, st->codec->block_align);
 524                         ast->sample_size= st->codec->block_align;
 525                     }
 526                     if (size%2) /* 2-aligned (fix for Stargate SG-1 - 3x18 - Shades of Grey.avi) */
 527                         url_fskip(pb, 1);
 528                     /* Force parsing as several audio frames can be in
 529                      * one packet and timestamps refer to packet start. */
 530                     st->need_parsing = AVSTREAM_PARSE_TIMESTAMPS;
 531                     /* ADTS header is in extradata, AAC without header must be
 532                      * stored as exact frames. Parser not needed and it will
 533                      * fail. */
 534                     if (st->codec->codec_id == CODEC_ID_AAC && st->codec->extradata_size)
 535                         st->need_parsing = AVSTREAM_PARSE_NONE;
 536                     /* AVI files with Xan DPCM audio (wrongly) declare PCM
 537                      * audio in the header but have Axan as stream_code_tag. */
 538                     if (st->codec->stream_codec_tag == AV_RL32("Axan")){
 539                         st->codec->codec_id  = CODEC_ID_XAN_DPCM;
 540                         st->codec->codec_tag = 0;
 541                     }
 542                     if (amv_file_format)
 543                         st->codec->codec_id  = CODEC_ID_ADPCM_IMA_AMV;
 544                     break;
 545                 default:
 546                     st->codec->codec_type = CODEC_TYPE_DATA;
 547                     st->codec->codec_id= CODEC_ID_NONE;
 548                     st->codec->codec_tag= 0;
 549                     url_fskip(pb, size);
 550                     break;
 551                 }
 552             }
 553             break;
 554         case MKTAG('i', 'n', 'd', 'x'):
 555             i= url_ftell(pb);
 556             if(!url_is_streamed(pb) && !(s->flags & AVFMT_FLAG_IGNIDX)){
 557                 read_braindead_odml_indx(s, 0);
 558             }
 559             url_fseek(pb, i+size, SEEK_SET);
 560             break;
 561         case MKTAG('v', 'p', 'r', 'p'):
 562             if(stream_index < (unsigned)s->nb_streams && size > 9*4){
 563                 AVRational active, active_aspect;
 564
 565                 st = s->streams[stream_index];
 566                 get_le32(pb);
 567                 get_le32(pb);
 568                 get_le32(pb);
 569                 get_le32(pb);
 570                 get_le32(pb);
 571
 572                 active_aspect.den= get_le16(pb);
 573                 active_aspect.num= get_le16(pb);
 574                 active.num       = get_le32(pb);
 575                 active.den       = get_le32(pb);
 576                 get_le32(pb); //nbFieldsPerFrame
 577
 578                 if(active_aspect.num && active_aspect.den && active.num && active.den){
 579                     st->sample_aspect_ratio= av_div_q(active_aspect, active);
 580 //av_log(s, AV_LOG_ERROR, "vprp %d/%d %d/%d\n", active_aspect.num, active_aspect.den, active.num, active.den);
 581                 }
 582                 size -= 9*4;
 583             }
 584             url_fseek(pb, size, SEEK_CUR);
 585             break;
 586         case MKTAG('I', 'N', 'A', 'M'):
 587             avi_read_tag(s, "Title", size);
 588             break;
 589         case MKTAG('I', 'A', 'R', 'T'):
 590             avi_read_tag(s, "Artist", size);
 591             break;
 592         case MKTAG('I', 'C', 'O', 'P'):
 593             avi_read_tag(s, "Copyright", size);
 594             break;
 595         case MKTAG('I', 'C', 'M', 'T'):
 596             avi_read_tag(s, "Comment", size);
 597             break;
 598         case MKTAG('I', 'G', 'N', 'R'):
 599             avi_read_tag(s, "Genre", size);
 600             break;
 601         case MKTAG('I', 'P', 'R', 'D'):
 602             avi_read_tag(s, "Album", size);
 603             break;
 604         case MKTAG('I', 'P', 'R', 'T'):
 605             avi_read_tag(s, "Track", size);
 606             break;
 607         default:
 608             if(size > 1000000){
 609                 av_log(s, AV_LOG_ERROR, "Something went wrong during header parsing, "
 610                                         "I will ignore it and try to continue anyway.\n");
 611                 avi->movi_list = url_ftell(pb) - 4;
 612                 avi->movi_end  = url_fsize(pb);
 613                 goto end_of_header;
 614             }
 615             /* skip tag */
 616             size += (size & 1);
 617             url_fskip(pb, size);
 618             break;
 619         }
 620     }
 621  end_of_header:
 622     /* check stream number */
 623     if (stream_index != s->nb_streams - 1) {
 624     fail:
 625         return -1;
 626     }
 627
 628     if(!avi->index_loaded && !url_is_streamed(pb))
 629         avi_load_index(s);
 630     avi->index_loaded = 1;
 631     avi->non_interleaved |= guess_ni_flag(s);
 632     if(avi->non_interleaved) {
 633         av_log(s, AV_LOG_INFO, "non-interleaved AVI\n");
 634         clean_index(s);
 635     }
 636
 637     return 0;
 638 }
 639
 640 static int get_stream_idx(int *d){
 641     if(    d[0] >= '0' && d[0] <= '9'
 642         && d[1] >= '0' && d[1] <= '9'){
 643         return (d[0] - '0') * 10 + (d[1] - '0');
 644     }else{
 645         return 100; //invalid stream ID
 646     }
 647 }
 648
 649 static int avi_read_packet(AVFormatContext *s, AVPacket *pkt)
 650 {
 651     AVIContext *avi = s->priv_data;
 652     ByteIOContext *pb = s->pb;
 653     int n, d[8];
 654     unsigned int size;
 655     int64_t i, sync;
 656     void* dstr;
 657
 658     if (CONFIG_DV_DEMUXER && avi->dv_demux) {
 659         int size = dv_get_packet(avi->dv_demux, pkt);
 660         if (size >= 0)
 661             return size;
 662     }
 663
 664     if(avi->non_interleaved){
 665         int best_stream_index = 0;
 666         AVStream *best_st= NULL;
 667         AVIStream *best_ast;
 668         int64_t best_ts= INT64_MAX;
 669         int i;
 670
 671         for(i=0; i<s->nb_streams; i++){
 672             AVStream *st = s->streams[i];
 673             AVIStream *ast = st->priv_data;
 674             int64_t ts= ast->frame_offset;
 675
 676             if(ast->sample_size)
 677                 ts /= ast->sample_size;
 678             ts= av_rescale(ts, AV_TIME_BASE * (int64_t)st->time_base.num, st->time_base.den);
 679
 680 //            av_log(s, AV_LOG_DEBUG, "%"PRId64" %d/%d %"PRId64"\n", ts, st->time_base.num, st->time_base.den, ast->frame_offset);
 681             if(ts < best_ts && st->nb_index_entries){
 682                 best_ts= ts;
 683                 best_st= st;
 684                 best_stream_index= i;
 685             }
 686         }
 687         if(!best_st)
 688             return -1;
 689
 690         best_ast = best_st->priv_data;
 691         best_ts= av_rescale(best_ts, best_st->time_base.den, AV_TIME_BASE * (int64_t)best_st->time_base.num); //FIXME a little ugly
 692         if(best_ast->remaining)
 693             i= av_index_search_timestamp(best_st, best_ts, AVSEEK_FLAG_ANY | AVSEEK_FLAG_BACKWARD);
 694         else{
 695             i= av_index_search_timestamp(best_st, best_ts, AVSEEK_FLAG_ANY);
 696             if(i>=0)
 697                 best_ast->frame_offset= best_st->index_entries[i].timestamp
 698                                       * FFMAX(1, best_ast->sample_size);
 699         }
 700
 701 //        av_log(s, AV_LOG_DEBUG, "%d\n", i);
 702         if(i>=0){
 703             int64_t pos= best_st->index_entries[i].pos;
 704             pos += best_ast->packet_size - best_ast->remaining;
 705             url_fseek(s->pb, pos + 8, SEEK_SET);
 706 //        av_log(s, AV_LOG_DEBUG, "pos=%"PRId64"\n", pos);
 707
 708             assert(best_ast->remaining <= best_ast->packet_size);
 709
 710             avi->stream_index= best_stream_index;
 711             if(!best_ast->remaining)
 712                 best_ast->packet_size=
 713                 best_ast->remaining= best_st->index_entries[i].size;
 714         }
 715     }
 716
 717 resync:
 718     if(avi->stream_index >= 0){
 719         AVStream *st= s->streams[ avi->stream_index ];
 720         AVIStream *ast= st->priv_data;
 721         int size, err;
 722
 723         if(ast->sample_size <= 1) // minorityreport.AVI block_align=1024 sample_size=1 IMA-ADPCM
 724             size= INT_MAX;
 725         else if(ast->sample_size < 32)
 726             size= 64*ast->sample_size;
 727         else
 728             size= ast->sample_size;
 729
 730         if(size > ast->remaining)
 731             size= ast->remaining;
 732         avi->last_pkt_pos= url_ftell(pb);
 733         err= av_get_packet(pb, pkt, size);
 734         if(err<0)
 735             return err;
 736
 737         if(ast->has_pal && pkt->data && pkt->size<(unsigned)INT_MAX/2){
 738             void *ptr= av_realloc(pkt->data, pkt->size + 4*256 + FF_INPUT_BUFFER_PADDING_SIZE);
 739             if(ptr){
 740             ast->has_pal=0;
 741             pkt->size += 4*256;
 742             pkt->data= ptr;
 743                 memcpy(pkt->data + pkt->size - 4*256, ast->pal, 4*256);
 744             }else
 745                 av_log(s, AV_LOG_ERROR, "Failed to append palette\n");
 746         }
 747
 748         if (CONFIG_DV_DEMUXER && avi->dv_demux) {
 749             dstr = pkt->destruct;
 750             size = dv_produce_packet(avi->dv_demux, pkt,
 751                                     pkt->data, pkt->size);
 752             pkt->destruct = dstr;
 753             pkt->flags |= PKT_FLAG_KEY;
 754         } else {
 755             /* XXX: How to handle B-frames in AVI? */
 756             pkt->dts = ast->frame_offset;
 757 //                pkt->dts += ast->start;
 758             if(ast->sample_size)
 759                 pkt->dts /= ast->sample_size;
 760 //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);
 761             pkt->stream_index = avi->stream_index;
 762
 763             if (st->codec->codec_type == CODEC_TYPE_VIDEO) {
 764                 AVIndexEntry *e;
 765                 int index;
 766                 assert(st->index_entries);
 767
 768                 index= av_index_search_timestamp(st, pkt->dts, 0);
 769                 e= &st->index_entries[index];
 770
 771                 if(index >= 0 && e->timestamp == ast->frame_offset){
 772                     if (e->flags & AVINDEX_KEYFRAME)
 773                         pkt->flags |= PKT_FLAG_KEY;
 774                 }
 775             } else {
 776                 pkt->flags |= PKT_FLAG_KEY;
 777             }
 778             if(ast->sample_size)
 779                 ast->frame_offset += pkt->size;
 780             else
 781                 ast->frame_offset++;
 782         }
 783         ast->remaining -= size;
 784         if(!ast->remaining){
 785             avi->stream_index= -1;
 786             ast->packet_size= 0;
 787         }
 788
 789         return size;
 790     }
 791
 792     memset(d, -1, sizeof(int)*8);
 793     for(i=sync=url_ftell(pb); !url_feof(pb); i++) {
 794         int j;
 795
 796         for(j=0; j<7; j++)
 797             d[j]= d[j+1];
 798         d[7]= get_byte(pb);
 799
 800         size= d[4] + (d[5]<<8) + (d[6]<<16) + (d[7]<<24);
 801
 802         n= get_stream_idx(d+2);
 803 //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);
 804         if(i + (uint64_t)size > avi->fsize || d[0]<0)
 805             continue;
 806
 807         //parse ix##
 808         if(  (d[0] == 'i' && d[1] == 'x' && n < s->nb_streams)
 809         //parse JUNK
 810            ||(d[0] == 'J' && d[1] == 'U' && d[2] == 'N' && d[3] == 'K')
 811            ||(d[0] == 'i' && d[1] == 'd' && d[2] == 'x' && d[3] == '1')){
 812             url_fskip(pb, size);
 813 //av_log(s, AV_LOG_DEBUG, "SKIP\n");
 814             goto resync;
 815         }
 816
 817         n= get_stream_idx(d);
 818
 819         if(!((i-avi->last_pkt_pos)&1) && get_stream_idx(d+1) < s->nb_streams)
 820             continue;
 821
 822         //parse ##dc/##wb
 823         if(n < s->nb_streams){
 824             AVStream *st;
 825             AVIStream *ast;
 826             st = s->streams[n];
 827             ast = st->priv_data;
 828
 829             if(s->nb_streams>=2){
 830                 AVStream *st1  = s->streams[1];
 831                 AVIStream *ast1= st1->priv_data;
 832                 //workaround for broken small-file-bug402.avi
 833                 if(   d[2] == 'w' && d[3] == 'b'
 834                    && n==0
 835                    && st ->codec->codec_type == CODEC_TYPE_VIDEO
 836                    && st1->codec->codec_type == CODEC_TYPE_AUDIO
 837                    && ast->prefix == 'd'*256+'c'
 838                    && (d[2]*256+d[3] == ast1->prefix || !ast1->prefix_count)
 839                   ){
 840                     n=1;
 841                     st = st1;
 842                     ast = ast1;
 843                     av_log(s, AV_LOG_WARNING, "Invalid stream + prefix combination, assuming audio.\n");
 844                 }
 845             }
 846
 847
 848             if(   (st->discard >= AVDISCARD_DEFAULT && size==0)
 849                /*|| (st->discard >= AVDISCARD_NONKEY && !(pkt->flags & PKT_FLAG_KEY))*/ //FIXME needs a little reordering
 850                || st->discard >= AVDISCARD_ALL){
 851                 if(ast->sample_size) ast->frame_offset += pkt->size;
 852                 else                 ast->frame_offset++;
 853                 url_fskip(pb, size);
 854                 goto resync;
 855             }
 856
 857             if (d[2] == 'p' && d[3] == 'c' && size<=4*256+4) {
 858                 int k = get_byte(pb);
 859                 int last = (k + get_byte(pb) - 1) & 0xFF;
 860
 861                 get_le16(pb); //flags
 862
 863                 for (; k <= last; k++)
 864                     ast->pal[k] = get_be32(pb)>>8;// b + (g << 8) + (r << 16);
 865                 ast->has_pal= 1;
 866                 goto resync;
 867             } else if(   ((ast->prefix_count<5 || sync+9 > i) && d[2]<128 && d[3]<128) ||
 868                          d[2]*256+d[3] == ast->prefix /*||
 869                          (d[2] == 'd' && d[3] == 'c') ||
 870                          (d[2] == 'w' && d[3] == 'b')*/) {
 871
 872 //av_log(s, AV_LOG_DEBUG, "OK\n");
 873                 if(d[2]*256+d[3] == ast->prefix)
 874                     ast->prefix_count++;
 875                 else{
 876                     ast->prefix= d[2]*256+d[3];
 877                     ast->prefix_count= 0;
 878                 }
 879
 880                 avi->stream_index= n;
 881                 ast->packet_size= size + 8;
 882                 ast->remaining= size;
 883
 884                 {
 885                     uint64_t pos= url_ftell(pb) - 8;
 886                     if(!st->index_entries || !st->nb_index_entries || st->index_entries[st->nb_index_entries - 1].pos < pos){
 887                         av_add_index_entry(st, pos, ast->frame_offset / FFMAX(1, ast->sample_size), size, 0, AVINDEX_KEYFRAME);
 888                     }
 889                 }
 890                 goto resync;
 891             }
 892         }
 893     }
 894
 895     return AVERROR_EOF;
 896 }
 897
 898 /* XXX: We make the implicit supposition that the positions are sorted
 899    for each stream. */
 900 static int avi_read_idx1(AVFormatContext *s, int size)
 901 {
 902     AVIContext *avi = s->priv_data;
 903     ByteIOContext *pb = s->pb;
 904     int nb_index_entries, i;
 905     AVStream *st;
 906     AVIStream *ast;
 907     unsigned int index, tag, flags, pos, len;
 908     unsigned last_pos= -1;
 909
 910     nb_index_entries = size / 16;
 911     if (nb_index_entries <= 0)
 912         return -1;
 913
 914     /* Read the entries and sort them in each stream component. */
 915     for(i = 0; i < nb_index_entries; i++) {
 916         tag = get_le32(pb);
 917         flags = get_le32(pb);
 918         pos = get_le32(pb);
 919         len = get_le32(pb);
 920 #if defined(DEBUG_SEEK)
 921         av_log(s, AV_LOG_DEBUG, "%d: tag=0x%x flags=0x%x pos=0x%x len=%d/",
 922                i, tag, flags, pos, len);
 923 #endif
 924         if(i==0 && pos > avi->movi_list)
 925             avi->movi_list= 0; //FIXME better check
 926         pos += avi->movi_list;
 927
 928         index = ((tag & 0xff) - '0') * 10;
 929         index += ((tag >> 8) & 0xff) - '0';
 930         if (index >= s->nb_streams)
 931             continue;
 932         st = s->streams[index];
 933         ast = st->priv_data;
 934
 935 #if defined(DEBUG_SEEK)
 936         av_log(s, AV_LOG_DEBUG, "%d cum_len=%"PRId64"\n", len, ast->cum_len);
 937 #endif
 938         if(url_feof(pb))
 939             return -1;
 940
 941         if(last_pos == pos)
 942             avi->non_interleaved= 1;
 943         else
 944             av_add_index_entry(st, pos, ast->cum_len / FFMAX(1, ast->sample_size), len, 0, (flags&AVIIF_INDEX) ? AVINDEX_KEYFRAME : 0);
 945         if(ast->sample_size)
 946             ast->cum_len += len;
 947         else
 948             ast->cum_len ++;
 949         last_pos= pos;
 950     }
 951     return 0;
 952 }
 953
 954 static int guess_ni_flag(AVFormatContext *s){
 955     int i;
 956     int64_t last_start=0;
 957     int64_t first_end= INT64_MAX;
 958
 959     for(i=0; i<s->nb_streams; i++){
 960         AVStream *st = s->streams[i];
 961         int n= st->nb_index_entries;
 962
 963         if(n <= 0)
 964             continue;
 965
 966         if(st->index_entries[0].pos > last_start)
 967             last_start= st->index_entries[0].pos;
 968         if(st->index_entries[n-1].pos < first_end)
 969             first_end= st->index_entries[n-1].pos;
 970     }
 971     return last_start > first_end;
 972 }
 973
 974 static int avi_load_index(AVFormatContext *s)
 975 {
 976     AVIContext *avi = s->priv_data;
 977     ByteIOContext *pb = s->pb;
 978     uint32_t tag, size;
 979     int64_t pos= url_ftell(pb);
 980
 981     url_fseek(pb, avi->movi_end, SEEK_SET);
 982 #ifdef DEBUG_SEEK
 983     printf("movi_end=0x%"PRIx64"\n", avi->movi_end);
 984 #endif
 985     for(;;) {
 986         if (url_feof(pb))
 987             break;
 988         tag = get_le32(pb);
 989         size = get_le32(pb);
 990 #ifdef DEBUG_SEEK
 991         printf("tag=%c%c%c%c size=0x%x\n",
 992                tag & 0xff,
 993                (tag >> 8) & 0xff,
 994                (tag >> 16) & 0xff,
 995                (tag >> 24) & 0xff,
 996                size);
 997 #endif
 998         switch(tag) {
 999         case MKTAG('i', 'd', 'x', '1'):
1000             if (avi_read_idx1(s, size) < 0)
1001                 goto skip;
1002             else
1003                 goto the_end;
1004             break;
1005         default:
1006         skip:
1007             size += (size & 1);
1008             url_fskip(pb, size);
1009             break;
1010         }
1011     }
1012  the_end:
1013     url_fseek(pb, pos, SEEK_SET);
1014     return 0;
1015 }
1016
1017 static int avi_read_seek(AVFormatContext *s, int stream_index, int64_t timestamp, int flags)
1018 {
1019     AVIContext *avi = s->priv_data;
1020     AVStream *st;
1021     int i, index;
1022     int64_t pos;
1023
1024     if (!avi->index_loaded) {
1025         /* we only load the index on demand */
1026         avi_load_index(s);
1027         avi->index_loaded = 1;
1028     }
1029     assert(stream_index>= 0);
1030
1031     st = s->streams[stream_index];
1032     index= av_index_search_timestamp(st, timestamp, flags);
1033     if(index<0)
1034         return -1;
1035
1036     /* find the position */
1037     pos = st->index_entries[index].pos;
1038     timestamp = st->index_entries[index].timestamp;
1039
1040 //    av_log(s, AV_LOG_DEBUG, "XX %"PRId64" %d %"PRId64"\n", timestamp, index, st->index_entries[index].timestamp);
1041
1042     if (CONFIG_DV_DEMUXER && avi->dv_demux) {
1043         /* One and only one real stream for DV in AVI, and it has video  */
1044         /* offsets. Calling with other stream indexes should have failed */
1045         /* the av_index_search_timestamp call above.                     */
1046         assert(stream_index == 0);
1047
1048         /* Feed the DV video stream version of the timestamp to the */
1049         /* DV demux so it can synthesize correct timestamps.        */
1050         dv_offset_reset(avi->dv_demux, timestamp);
1051
1052         url_fseek(s->pb, pos, SEEK_SET);
1053         avi->stream_index= -1;
1054         return 0;
1055     }
1056
1057     for(i = 0; i < s->nb_streams; i++) {
1058         AVStream *st2 = s->streams[i];
1059         AVIStream *ast2 = st2->priv_data;
1060
1061         ast2->packet_size=
1062         ast2->remaining= 0;
1063
1064         if (st2->nb_index_entries <= 0)
1065             continue;
1066
1067 //        assert(st2->codec->block_align);
1068         assert((int64_t)st2->time_base.num*ast2->rate == (int64_t)st2->time_base.den*ast2->scale);
1069         index = av_index_search_timestamp(
1070                 st2,
1071                 av_rescale(timestamp, st2->time_base.den*(int64_t)st->time_base.num, st->time_base.den * (int64_t)st2->time_base.num),
1072                 flags | AVSEEK_FLAG_BACKWARD);
1073         if(index<0)
1074             index=0;
1075
1076         if(!avi->non_interleaved){
1077             while(index>0 && st2->index_entries[index].pos > pos)
1078                 index--;
1079             while(index+1 < st2->nb_index_entries && st2->index_entries[index].pos < pos)
1080                 index++;
1081         }
1082
1083 //        av_log(s, AV_LOG_DEBUG, "%"PRId64" %d %"PRId64"\n", timestamp, index, st2->index_entries[index].timestamp);
1084         /* extract the current frame number */
1085         ast2->frame_offset = st2->index_entries[index].timestamp;
1086         if(ast2->sample_size)
1087             ast2->frame_offset *=ast2->sample_size;
1088     }
1089
1090     /* do the seek */
1091     url_fseek(s->pb, pos, SEEK_SET);
1092     avi->stream_index= -1;
1093     return 0;
1094 }
1095
1096 static int avi_read_close(AVFormatContext *s)
1097 {
1098     int i;
1099     AVIContext *avi = s->priv_data;
1100
1101     for(i=0;i<s->nb_streams;i++) {
1102         AVStream *st = s->streams[i];
1103         av_free(st->codec->palctrl);
1104     }
1105
1106     if (avi->dv_demux)
1107         av_free(avi->dv_demux);
1108
1109     return 0;
1110 }
1111
1112 static int avi_probe(AVProbeData *p)
1113 {
1114     int i;
1115
1116     /* check file header */
1117     for(i=0; avi_headers[i][0]; i++)
1118         if(!memcmp(p->buf  , avi_headers[i]  , 4) &&
1119            !memcmp(p->buf+8, avi_headers[i]+4, 4))
1120             return AVPROBE_SCORE_MAX;
1121
1122     return 0;
1123 }
1124
1125 AVInputFormat avi_demuxer = {
1126     "avi",
1127     NULL_IF_CONFIG_SMALL("AVI format"),
1128     sizeof(AVIContext),
1129     avi_probe,
1130     avi_read_header,
1131     avi_read_packet,
1132     avi_read_close,
1133     avi_read_seek,
1134 };