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