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