git.sesse.net Git - ffmpeg/blob - libavformat/rmdec.c

   1 /*
   2  * "Real" compatible demuxer.
   3  * Copyright (c) 2000, 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 #include "avformat.h"
  22 #include "rm.h"
  23 #include "avstring.h"
  24
  25 static inline void get_strl(ByteIOContext *pb, char *buf, int buf_size, int len)
  26 {
  27     int i;
  28     char *q, r;
  29
  30     q = buf;
  31     for(i=0;i<len;i++) {
  32         r = get_byte(pb);
  33         if (i < buf_size - 1)
  34             *q++ = r;
  35     }
  36     if (buf_size > 0) *q = '\0';
  37 }
  38
  39 static void get_str16(ByteIOContext *pb, char *buf, int buf_size)
  40 {
  41     get_strl(pb, buf, buf_size, get_be16(pb));
  42 }
  43
  44 static void get_str8(ByteIOContext *pb, char *buf, int buf_size)
  45 {
  46     get_strl(pb, buf, buf_size, get_byte(pb));
  47 }
  48
  49 static int rm_read_audio_stream_info(AVFormatContext *s, AVStream *st,
  50                                       int read_all)
  51 {
  52     RMContext *rm = s->priv_data;
  53     ByteIOContext *pb = &s->pb;
  54     char buf[256];
  55     uint32_t version;
  56     int i;
  57
  58     /* ra type header */
  59     version = get_be32(pb); /* version */
  60     if (((version >> 16) & 0xff) == 3) {
  61         int64_t startpos = url_ftell(pb);
  62         /* very old version */
  63         for(i = 0; i < 14; i++)
  64             get_byte(pb);
  65         get_str8(pb, s->title, sizeof(s->title));
  66         get_str8(pb, s->author, sizeof(s->author));
  67         get_str8(pb, s->copyright, sizeof(s->copyright));
  68         get_str8(pb, s->comment, sizeof(s->comment));
  69         if ((startpos + (version & 0xffff)) >= url_ftell(pb) + 2) {
  70         // fourcc (should always be "lpcJ")
  71         get_byte(pb);
  72         get_str8(pb, buf, sizeof(buf));
  73         }
  74         // Skip extra header crap (this should never happen)
  75         if ((startpos + (version & 0xffff)) > url_ftell(pb))
  76             url_fskip(pb, (version & 0xffff) + startpos - url_ftell(pb));
  77         st->codec->sample_rate = 8000;
  78         st->codec->channels = 1;
  79         st->codec->codec_type = CODEC_TYPE_AUDIO;
  80         st->codec->codec_id = CODEC_ID_RA_144;
  81     } else {
  82         int flavor, sub_packet_h, coded_framesize, sub_packet_size;
  83         /* old version (4) */
  84         get_be32(pb); /* .ra4 */
  85         get_be32(pb); /* data size */
  86         get_be16(pb); /* version2 */
  87         get_be32(pb); /* header size */
  88         flavor= get_be16(pb); /* add codec info / flavor */
  89         rm->coded_framesize = coded_framesize = get_be32(pb); /* coded frame size */
  90         get_be32(pb); /* ??? */
  91         get_be32(pb); /* ??? */
  92         get_be32(pb); /* ??? */
  93         rm->sub_packet_h = sub_packet_h = get_be16(pb); /* 1 */
  94         st->codec->block_align= get_be16(pb); /* frame size */
  95         rm->sub_packet_size = sub_packet_size = get_be16(pb); /* sub packet size */
  96         get_be16(pb); /* ??? */
  97         if (((version >> 16) & 0xff) == 5) {
  98             get_be16(pb); get_be16(pb); get_be16(pb); }
  99         st->codec->sample_rate = get_be16(pb);
 100         get_be32(pb);
 101         st->codec->channels = get_be16(pb);
 102         if (((version >> 16) & 0xff) == 5) {
 103             get_be32(pb);
 104             buf[0] = get_byte(pb);
 105             buf[1] = get_byte(pb);
 106             buf[2] = get_byte(pb);
 107             buf[3] = get_byte(pb);
 108             buf[4] = 0;
 109         } else {
 110             get_str8(pb, buf, sizeof(buf)); /* desc */
 111             get_str8(pb, buf, sizeof(buf)); /* desc */
 112         }
 113         st->codec->codec_type = CODEC_TYPE_AUDIO;
 114         if (!strcmp(buf, "dnet")) {
 115             st->codec->codec_id = CODEC_ID_AC3;
 116             st->need_parsing = AVSTREAM_PARSE_FULL;
 117         } else if (!strcmp(buf, "28_8")) {
 118             st->codec->codec_id = CODEC_ID_RA_288;
 119             st->codec->extradata_size= 0;
 120             rm->audio_framesize = st->codec->block_align;
 121             st->codec->block_align = coded_framesize;
 122
 123             if(rm->audio_framesize >= UINT_MAX / sub_packet_h){
 124                 av_log(s, AV_LOG_ERROR, "rm->audio_framesize * sub_packet_h too large\n");
 125                 return -1;
 126             }
 127
 128             rm->audiobuf = av_malloc(rm->audio_framesize * sub_packet_h);
 129         } else if ((!strcmp(buf, "cook")) || (!strcmp(buf, "atrc"))) {
 130             int codecdata_length, i;
 131             get_be16(pb); get_byte(pb);
 132             if (((version >> 16) & 0xff) == 5)
 133                 get_byte(pb);
 134             codecdata_length = get_be32(pb);
 135             if(codecdata_length + FF_INPUT_BUFFER_PADDING_SIZE <= (unsigned)codecdata_length){
 136                 av_log(s, AV_LOG_ERROR, "codecdata_length too large\n");
 137                 return -1;
 138             }
 139
 140             if (!strcmp(buf, "cook")) st->codec->codec_id = CODEC_ID_COOK;
 141             else st->codec->codec_id = CODEC_ID_ATRAC3;
 142             st->codec->extradata_size= codecdata_length;
 143             st->codec->extradata= av_mallocz(st->codec->extradata_size + FF_INPUT_BUFFER_PADDING_SIZE);
 144             for(i = 0; i < codecdata_length; i++)
 145                 ((uint8_t*)st->codec->extradata)[i] = get_byte(pb);
 146             rm->audio_framesize = st->codec->block_align;
 147             st->codec->block_align = rm->sub_packet_size;
 148
 149             if(rm->audio_framesize >= UINT_MAX / sub_packet_h){
 150                 av_log(s, AV_LOG_ERROR, "rm->audio_framesize * sub_packet_h too large\n");
 151                 return -1;
 152             }
 153
 154             rm->audiobuf = av_malloc(rm->audio_framesize * sub_packet_h);
 155         } else if (!strcmp(buf, "raac") || !strcmp(buf, "racp")) {
 156             int codecdata_length, i;
 157             get_be16(pb); get_byte(pb);
 158             if (((version >> 16) & 0xff) == 5)
 159                 get_byte(pb);
 160             st->codec->codec_id = CODEC_ID_AAC;
 161             codecdata_length = get_be32(pb);
 162             if(codecdata_length + FF_INPUT_BUFFER_PADDING_SIZE <= (unsigned)codecdata_length){
 163                 av_log(s, AV_LOG_ERROR, "codecdata_length too large\n");
 164                 return -1;
 165             }
 166             if (codecdata_length >= 1) {
 167                 st->codec->extradata_size = codecdata_length - 1;
 168                 st->codec->extradata = av_mallocz(st->codec->extradata_size + FF_INPUT_BUFFER_PADDING_SIZE);
 169                 get_byte(pb);
 170                 for(i = 0; i < st->codec->extradata_size; i++)
 171                     ((uint8_t*)st->codec->extradata)[i] = get_byte(pb);
 172             }
 173         } else {
 174             st->codec->codec_id = CODEC_ID_NONE;
 175             av_strlcpy(st->codec->codec_name, buf, sizeof(st->codec->codec_name));
 176         }
 177         if (read_all) {
 178             get_byte(pb);
 179             get_byte(pb);
 180             get_byte(pb);
 181
 182             get_str8(pb, s->title, sizeof(s->title));
 183             get_str8(pb, s->author, sizeof(s->author));
 184             get_str8(pb, s->copyright, sizeof(s->copyright));
 185             get_str8(pb, s->comment, sizeof(s->comment));
 186         }
 187     }
 188     return 0;
 189 }
 190
 191 static int rm_read_header_old(AVFormatContext *s, AVFormatParameters *ap)
 192 {
 193     RMContext *rm = s->priv_data;
 194     AVStream *st;
 195
 196     rm->old_format = 1;
 197     st = av_new_stream(s, 0);
 198     if (!st)
 199         return -1;
 200     return rm_read_audio_stream_info(s, st, 1);
 201 }
 202
 203 static int rm_read_header(AVFormatContext *s, AVFormatParameters *ap)
 204 {
 205     RMContext *rm = s->priv_data;
 206     AVStream *st;
 207     ByteIOContext *pb = &s->pb;
 208     unsigned int tag, v;
 209     int tag_size, size, codec_data_size, i;
 210     int64_t codec_pos;
 211     unsigned int start_time, duration;
 212     char buf[128];
 213     int flags = 0;
 214
 215     tag = get_le32(pb);
 216     if (tag == MKTAG('.', 'r', 'a', 0xfd)) {
 217         /* very old .ra format */
 218         return rm_read_header_old(s, ap);
 219     } else if (tag != MKTAG('.', 'R', 'M', 'F')) {
 220         return AVERROR(EIO);
 221     }
 222
 223     get_be32(pb); /* header size */
 224     get_be16(pb);
 225     get_be32(pb);
 226     get_be32(pb); /* number of headers */
 227
 228     for(;;) {
 229         if (url_feof(pb))
 230             goto fail;
 231         tag = get_le32(pb);
 232         tag_size = get_be32(pb);
 233         get_be16(pb);
 234 #if 0
 235         printf("tag=%c%c%c%c (%08x) size=%d\n",
 236                (tag) & 0xff,
 237                (tag >> 8) & 0xff,
 238                (tag >> 16) & 0xff,
 239                (tag >> 24) & 0xff,
 240                tag,
 241                tag_size);
 242 #endif
 243         if (tag_size < 10 && tag != MKTAG('D', 'A', 'T', 'A'))
 244             goto fail;
 245         switch(tag) {
 246         case MKTAG('P', 'R', 'O', 'P'):
 247             /* file header */
 248             get_be32(pb); /* max bit rate */
 249             get_be32(pb); /* avg bit rate */
 250             get_be32(pb); /* max packet size */
 251             get_be32(pb); /* avg packet size */
 252             get_be32(pb); /* nb packets */
 253             get_be32(pb); /* duration */
 254             get_be32(pb); /* preroll */
 255             get_be32(pb); /* index offset */
 256             get_be32(pb); /* data offset */
 257             get_be16(pb); /* nb streams */
 258             flags = get_be16(pb); /* flags */
 259             break;
 260         case MKTAG('C', 'O', 'N', 'T'):
 261             get_str16(pb, s->title, sizeof(s->title));
 262             get_str16(pb, s->author, sizeof(s->author));
 263             get_str16(pb, s->copyright, sizeof(s->copyright));
 264             get_str16(pb, s->comment, sizeof(s->comment));
 265             break;
 266         case MKTAG('M', 'D', 'P', 'R'):
 267             st = av_new_stream(s, 0);
 268             if (!st)
 269                 goto fail;
 270             st->id = get_be16(pb);
 271             get_be32(pb); /* max bit rate */
 272             st->codec->bit_rate = get_be32(pb); /* bit rate */
 273             get_be32(pb); /* max packet size */
 274             get_be32(pb); /* avg packet size */
 275             start_time = get_be32(pb); /* start time */
 276             get_be32(pb); /* preroll */
 277             duration = get_be32(pb); /* duration */
 278             st->start_time = start_time;
 279             st->duration = duration;
 280             get_str8(pb, buf, sizeof(buf)); /* desc */
 281             get_str8(pb, buf, sizeof(buf)); /* mimetype */
 282             codec_data_size = get_be32(pb);
 283             codec_pos = url_ftell(pb);
 284             st->codec->codec_type = CODEC_TYPE_DATA;
 285             av_set_pts_info(st, 64, 1, 1000);
 286
 287             v = get_be32(pb);
 288             if (v == MKTAG(0xfd, 'a', 'r', '.')) {
 289                 /* ra type header */
 290                 if (rm_read_audio_stream_info(s, st, 0))
 291                     return -1;
 292             } else {
 293                 int fps, fps2;
 294                 if (get_le32(pb) != MKTAG('V', 'I', 'D', 'O')) {
 295                 fail1:
 296                     av_log(st->codec, AV_LOG_ERROR, "Unsupported video codec\n");
 297                     goto skip;
 298                 }
 299                 st->codec->codec_tag = get_le32(pb);
 300 //                av_log(NULL, AV_LOG_DEBUG, "%X %X\n", st->codec->codec_tag, MKTAG('R', 'V', '2', '0'));
 301                 if (   st->codec->codec_tag != MKTAG('R', 'V', '1', '0')
 302                     && st->codec->codec_tag != MKTAG('R', 'V', '2', '0')
 303                     && st->codec->codec_tag != MKTAG('R', 'V', '3', '0')
 304                     && st->codec->codec_tag != MKTAG('R', 'V', '4', '0'))
 305                     goto fail1;
 306                 st->codec->width = get_be16(pb);
 307                 st->codec->height = get_be16(pb);
 308                 st->codec->time_base.num= 1;
 309                 fps= get_be16(pb);
 310                 st->codec->codec_type = CODEC_TYPE_VIDEO;
 311                 get_be32(pb);
 312                 fps2= get_be16(pb);
 313                 get_be16(pb);
 314
 315                 st->codec->extradata_size= codec_data_size - (url_ftell(pb) - codec_pos);
 316
 317                 if(st->codec->extradata_size + FF_INPUT_BUFFER_PADDING_SIZE <= (unsigned)st->codec->extradata_size){
 318                     //check is redundant as get_buffer() will catch this
 319                     av_log(s, AV_LOG_ERROR, "st->codec->extradata_size too large\n");
 320                     return -1;
 321                 }
 322                 st->codec->extradata= av_mallocz(st->codec->extradata_size + FF_INPUT_BUFFER_PADDING_SIZE);
 323                 get_buffer(pb, st->codec->extradata, st->codec->extradata_size);
 324
 325 //                av_log(NULL, AV_LOG_DEBUG, "fps= %d fps2= %d\n", fps, fps2);
 326                 st->codec->time_base.den = fps * st->codec->time_base.num;
 327                 switch(((uint8_t*)st->codec->extradata)[4]>>4){
 328                 case 1: st->codec->codec_id = CODEC_ID_RV10; break;
 329                 case 2: st->codec->codec_id = CODEC_ID_RV20; break;
 330                 case 3: st->codec->codec_id = CODEC_ID_RV30; break;
 331                 case 4: st->codec->codec_id = CODEC_ID_RV40; break;
 332                 default: goto fail1;
 333                 }
 334             }
 335 skip:
 336             /* skip codec info */
 337             size = url_ftell(pb) - codec_pos;
 338             url_fskip(pb, codec_data_size - size);
 339             break;
 340         case MKTAG('D', 'A', 'T', 'A'):
 341             goto header_end;
 342         default:
 343             /* unknown tag: skip it */
 344             url_fskip(pb, tag_size - 10);
 345             break;
 346         }
 347     }
 348  header_end:
 349     rm->nb_packets = get_be32(pb); /* number of packets */
 350     if (!rm->nb_packets && (flags & 4))
 351         rm->nb_packets = 3600 * 25;
 352     get_be32(pb); /* next data header */
 353     return 0;
 354
 355  fail:
 356     for(i=0;i<s->nb_streams;i++) {
 357         av_free(s->streams[i]);
 358     }
 359     return AVERROR(EIO);
 360 }
 361
 362 static int get_num(ByteIOContext *pb, int *len)
 363 {
 364     int n, n1;
 365
 366     n = get_be16(pb);
 367     (*len)-=2;
 368     if (n >= 0x4000) {
 369         return n - 0x4000;
 370     } else {
 371         n1 = get_be16(pb);
 372         (*len)-=2;
 373         return (n << 16) | n1;
 374     }
 375 }
 376
 377 /* multiple of 20 bytes for ra144 (ugly) */
 378 #define RAW_PACKET_SIZE 1000
 379
 380 static int sync(AVFormatContext *s, int64_t *timestamp, int *flags, int *stream_index, int64_t *pos){
 381     RMContext *rm = s->priv_data;
 382     ByteIOContext *pb = &s->pb;
 383     int len, num, res, i;
 384     AVStream *st;
 385     uint32_t state=0xFFFFFFFF;
 386
 387     while(!url_feof(pb)){
 388         *pos= url_ftell(pb);
 389         if(rm->remaining_len > 0){
 390             num= rm->current_stream;
 391             len= rm->remaining_len;
 392             *timestamp = AV_NOPTS_VALUE;
 393             *flags= 0;
 394         }else{
 395             state= (state<<8) + get_byte(pb);
 396
 397             if(state == MKBETAG('I', 'N', 'D', 'X')){
 398                 len = get_be16(pb) - 6;
 399                 if(len<0)
 400                     continue;
 401                 goto skip;
 402             }
 403
 404             if(state > (unsigned)0xFFFF || state < 12)
 405                 continue;
 406             len=state;
 407             state= 0xFFFFFFFF;
 408
 409             num = get_be16(pb);
 410             *timestamp = get_be32(pb);
 411             res= get_byte(pb); /* reserved */
 412             *flags = get_byte(pb); /* flags */
 413
 414
 415             len -= 12;
 416         }
 417         for(i=0;i<s->nb_streams;i++) {
 418             st = s->streams[i];
 419             if (num == st->id)
 420                 break;
 421         }
 422         if (i == s->nb_streams) {
 423 skip:
 424             /* skip packet if unknown number */
 425             url_fskip(pb, len);
 426             rm->remaining_len -= len;
 427             continue;
 428         }
 429         *stream_index= i;
 430
 431         return len;
 432     }
 433     return -1;
 434 }
 435
 436 static int rm_read_packet(AVFormatContext *s, AVPacket *pkt)
 437 {
 438     RMContext *rm = s->priv_data;
 439     ByteIOContext *pb = &s->pb;
 440     AVStream *st;
 441     int i, len, j;
 442     int64_t timestamp, pos;
 443     uint8_t *ptr;
 444     int flags;
 445
 446     if (rm->audio_pkt_cnt) {
 447         // If there are queued audio packet return them first
 448         st = s->streams[rm->audio_stream_num];
 449         if (st->codec->codec_id == CODEC_ID_AAC)
 450             av_get_packet(pb, pkt, rm->sub_packet_lengths[rm->sub_packet_cnt - rm->audio_pkt_cnt]);
 451         else {
 452         av_new_packet(pkt, st->codec->block_align);
 453         memcpy(pkt->data, rm->audiobuf + st->codec->block_align *
 454                (rm->sub_packet_h * rm->audio_framesize / st->codec->block_align - rm->audio_pkt_cnt),
 455                st->codec->block_align);
 456         }
 457         rm->audio_pkt_cnt--;
 458         pkt->flags = 0;
 459         pkt->stream_index = rm->audio_stream_num;
 460     } else if (rm->old_format) {
 461         st = s->streams[0];
 462         if (st->codec->codec_id == CODEC_ID_RA_288) {
 463             int x, y;
 464
 465             for (y = 0; y < rm->sub_packet_h; y++)
 466                 for (x = 0; x < rm->sub_packet_h/2; x++)
 467                     if (get_buffer(pb, rm->audiobuf+x*2*rm->audio_framesize+y*rm->coded_framesize, rm->coded_framesize) <= 0)
 468                         return AVERROR(EIO);
 469             rm->audio_stream_num = 0;
 470             rm->audio_pkt_cnt = rm->sub_packet_h * rm->audio_framesize / st->codec->block_align - 1;
 471             // Release first audio packet
 472             av_new_packet(pkt, st->codec->block_align);
 473             memcpy(pkt->data, rm->audiobuf, st->codec->block_align);
 474             pkt->flags |= PKT_FLAG_KEY; // Mark first packet as keyframe
 475             pkt->stream_index = 0;
 476         } else {
 477             /* just read raw bytes */
 478             len = RAW_PACKET_SIZE;
 479             len= av_get_packet(pb, pkt, len);
 480             pkt->stream_index = 0;
 481             if (len <= 0) {
 482                 return AVERROR(EIO);
 483             }
 484             pkt->size = len;
 485         }
 486     } else {
 487         int seq=1;
 488 resync:
 489         len=sync(s, &timestamp, &flags, &i, &pos);
 490         if(len<0)
 491             return AVERROR(EIO);
 492         st = s->streams[i];
 493
 494         if (st->codec->codec_type == CODEC_TYPE_VIDEO) {
 495             int h, pic_num, len2, pos;
 496
 497             h= get_byte(pb); len--;
 498             if(!(h & 0x40)){
 499                 seq = get_byte(pb); len--;
 500             }
 501
 502             if((h & 0xc0) == 0x40){
 503                 len2= pos= 0;
 504             }else{
 505                 len2 = get_num(pb, &len);
 506                 pos = get_num(pb, &len);
 507             }
 508             /* picture number */
 509             pic_num= get_byte(pb); len--;
 510             rm->remaining_len= len;
 511             rm->current_stream= st->id;
 512
 513 //            av_log(NULL, AV_LOG_DEBUG, "%X len:%d pos:%d len2:%d pic_num:%d\n",h, len, pos, len2, pic_num);
 514             if((h & 0xc0) == 0x80)
 515                 len=pos;
 516             if(len2 && len2<len)
 517                 len=len2;
 518             rm->remaining_len-= len;
 519             av_get_packet(pb, pkt, len);
 520
 521         } else if (st->codec->codec_type == CODEC_TYPE_AUDIO) {
 522             if ((st->codec->codec_id == CODEC_ID_RA_288) ||
 523                 (st->codec->codec_id == CODEC_ID_COOK) ||
 524                 (st->codec->codec_id == CODEC_ID_ATRAC3)) {
 525                 int x;
 526                 int sps = rm->sub_packet_size;
 527                 int cfs = rm->coded_framesize;
 528                 int h = rm->sub_packet_h;
 529                 int y = rm->sub_packet_cnt;
 530                 int w = rm->audio_framesize;
 531
 532                 if (flags & 2)
 533                     y = rm->sub_packet_cnt = 0;
 534                 if (!y)
 535                     rm->audiotimestamp = timestamp;
 536
 537                 switch(st->codec->codec_id) {
 538                     case CODEC_ID_RA_288:
 539                         for (x = 0; x < h/2; x++)
 540                             get_buffer(pb, rm->audiobuf+x*2*w+y*cfs, cfs);
 541                         break;
 542                     case CODEC_ID_ATRAC3:
 543                     case CODEC_ID_COOK:
 544                         for (x = 0; x < w/sps; x++)
 545                             get_buffer(pb, rm->audiobuf+sps*(h*x+((h+1)/2)*(y&1)+(y>>1)), sps);
 546                         break;
 547                 }
 548
 549                 if (++(rm->sub_packet_cnt) < h)
 550                     goto resync;
 551                 else {
 552                     rm->sub_packet_cnt = 0;
 553                     rm->audio_stream_num = i;
 554                     rm->audio_pkt_cnt = h * w / st->codec->block_align - 1;
 555                     // Release first audio packet
 556                     av_new_packet(pkt, st->codec->block_align);
 557                     memcpy(pkt->data, rm->audiobuf, st->codec->block_align);
 558                     timestamp = rm->audiotimestamp;
 559                     flags = 2; // Mark first packet as keyframe
 560                 }
 561             } else if (st->codec->codec_id == CODEC_ID_AAC) {
 562                 int x;
 563                 rm->audio_stream_num = i;
 564                 rm->sub_packet_cnt = (get_be16(pb) & 0xf0) >> 4;
 565                 if (rm->sub_packet_cnt) {
 566                     for (x = 0; x < rm->sub_packet_cnt; x++)
 567                         rm->sub_packet_lengths[x] = get_be16(pb);
 568                     // Release first audio packet
 569                     rm->audio_pkt_cnt = rm->sub_packet_cnt - 1;
 570                     av_get_packet(pb, pkt, rm->sub_packet_lengths[0]);
 571                     flags = 2; // Mark first packet as keyframe
 572                 }
 573             } else
 574                 av_get_packet(pb, pkt, len);
 575
 576         } else
 577             av_get_packet(pb, pkt, len);
 578
 579         if(  (st->discard >= AVDISCARD_NONKEY && !(flags&2))
 580            || st->discard >= AVDISCARD_ALL){
 581             av_free_packet(pkt);
 582             goto resync;
 583         }
 584
 585         pkt->stream_index = i;
 586
 587 #if 0
 588         if (st->codec->codec_type == CODEC_TYPE_VIDEO) {
 589             if(st->codec->codec_id == CODEC_ID_RV20){
 590                 int seq= 128*(pkt->data[2]&0x7F) + (pkt->data[3]>>1);
 591                 av_log(NULL, AV_LOG_DEBUG, "%d %"PRId64" %d\n", timestamp, timestamp*512LL/25, seq);
 592
 593                 seq |= (timestamp&~0x3FFF);
 594                 if(seq - timestamp >  0x2000) seq -= 0x4000;
 595                 if(seq - timestamp < -0x2000) seq += 0x4000;
 596             }
 597         }
 598 #endif
 599         pkt->pts= timestamp;
 600         if(flags&2){
 601             pkt->flags |= PKT_FLAG_KEY;
 602             if((seq&0x7F) == 1)
 603                 av_add_index_entry(st, pos, timestamp, 0, 0, AVINDEX_KEYFRAME);
 604         }
 605     }
 606
 607     /* for AC3, needs to swap bytes */
 608     if (st->codec->codec_id == CODEC_ID_AC3) {
 609         ptr = pkt->data;
 610         for(j=0;j<pkt->size;j+=2) {
 611             FFSWAP(int, ptr[0], ptr[1]);
 612             ptr += 2;
 613         }
 614     }
 615     return 0;
 616 }
 617
 618 static int rm_read_close(AVFormatContext *s)
 619 {
 620     RMContext *rm = s->priv_data;
 621
 622     av_free(rm->audiobuf);
 623     return 0;
 624 }
 625
 626 static int rm_probe(AVProbeData *p)
 627 {
 628     /* check file header */
 629     if ((p->buf[0] == '.' && p->buf[1] == 'R' &&
 630          p->buf[2] == 'M' && p->buf[3] == 'F' &&
 631          p->buf[4] == 0 && p->buf[5] == 0) ||
 632         (p->buf[0] == '.' && p->buf[1] == 'r' &&
 633          p->buf[2] == 'a' && p->buf[3] == 0xfd))
 634         return AVPROBE_SCORE_MAX;
 635     else
 636         return 0;
 637 }
 638
 639 static int64_t rm_read_dts(AVFormatContext *s, int stream_index,
 640                                int64_t *ppos, int64_t pos_limit)
 641 {
 642     RMContext *rm = s->priv_data;
 643     int64_t pos, dts;
 644     int stream_index2, flags, len, h;
 645
 646     pos = *ppos;
 647
 648     if(rm->old_format)
 649         return AV_NOPTS_VALUE;
 650
 651     url_fseek(&s->pb, pos, SEEK_SET);
 652     rm->remaining_len=0;
 653     for(;;){
 654         int seq=1;
 655         AVStream *st;
 656
 657         len=sync(s, &dts, &flags, &stream_index2, &pos);
 658         if(len<0)
 659             return AV_NOPTS_VALUE;
 660
 661         st = s->streams[stream_index2];
 662         if (st->codec->codec_type == CODEC_TYPE_VIDEO) {
 663             h= get_byte(&s->pb); len--;
 664             if(!(h & 0x40)){
 665                 seq = get_byte(&s->pb); len--;
 666             }
 667         }
 668
 669         if((flags&2) && (seq&0x7F) == 1){
 670 //            av_log(s, AV_LOG_DEBUG, "%d %d-%d %"PRId64" %d\n", flags, stream_index2, stream_index, dts, seq);
 671             av_add_index_entry(st, pos, dts, 0, 0, AVINDEX_KEYFRAME);
 672             if(stream_index2 == stream_index)
 673                 break;
 674         }
 675
 676         url_fskip(&s->pb, len);
 677     }
 678     *ppos = pos;
 679     return dts;
 680 }
 681
 682 AVInputFormat rm_demuxer = {
 683     "rm",
 684     "rm format",
 685     sizeof(RMContext),
 686     rm_probe,
 687     rm_read_header,
 688     rm_read_packet,
 689     rm_read_close,
 690     NULL,
 691     rm_read_dts,
 692 };