libavformat/rm.c

   1 /*
   2  * "Real" compatible mux and demux.
   3  * Copyright (c) 2000, 2001 Fabrice Bellard.
   4  *
   5  * This library is free software; you can redistribute it and/or
   6  * modify it under the terms of the GNU Lesser General Public
   7  * License as published by the Free Software Foundation; either
   8  * version 2 of the License, or (at your option) any later version.
   9  *
  10  * This library is distributed in the hope that it will be useful,
  11  * but WITHOUT ANY WARRANTY; without even the implied warranty of
  12  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
  13  * Lesser General Public License for more details.
  14  *
  15  * You should have received a copy of the GNU Lesser General Public
  16  * License along with this library; if not, write to the Free Software
  17  * Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA  02111-1307  USA
  18  */
  19 #include "avformat.h"
  20
  21 /* in ms */
  22 #define BUFFER_DURATION 0
  23
  24 typedef struct {
  25     int nb_packets;
  26     int packet_total_size;
  27     int packet_max_size;
  28     /* codec related output */
  29     int bit_rate;
  30     float frame_rate;
  31     int nb_frames;    /* current frame number */
  32     int total_frames; /* total number of frames */
  33     int num;
  34     AVCodecContext *enc;
  35 } StreamInfo;
  36
  37 typedef struct {
  38     StreamInfo streams[2];
  39     StreamInfo *audio_stream, *video_stream;
  40     int data_pos; /* position of the data after the header */
  41     int nb_packets;
  42     int old_format;
  43 } RMContext;
  44
  45 #ifdef CONFIG_ENCODERS
  46 static void put_str(ByteIOContext *s, const char *tag)
  47 {
  48     put_be16(s,strlen(tag));
  49     while (*tag) {
  50         put_byte(s, *tag++);
  51     }
  52 }
  53
  54 static void put_str8(ByteIOContext *s, const char *tag)
  55 {
  56     put_byte(s, strlen(tag));
  57     while (*tag) {
  58         put_byte(s, *tag++);
  59     }
  60 }
  61
  62 static void rv10_write_header(AVFormatContext *ctx,
  63                               int data_size, int index_pos)
  64 {
  65     RMContext *rm = ctx->priv_data;
  66     ByteIOContext *s = &ctx->pb;
  67     StreamInfo *stream;
  68     unsigned char *data_offset_ptr, *start_ptr;
  69     const char *desc, *mimetype;
  70     int nb_packets, packet_total_size, packet_max_size, size, packet_avg_size, i;
  71     int bit_rate, v, duration, flags, data_pos;
  72
  73     start_ptr = s->buf_ptr;
  74
  75     put_tag(s, ".RMF");
  76     put_be32(s,18); /* header size */
  77     put_be16(s,0);
  78     put_be32(s,0);
  79     put_be32(s,4 + ctx->nb_streams); /* num headers */
  80
  81     put_tag(s,"PROP");
  82     put_be32(s, 50);
  83     put_be16(s, 0);
  84     packet_max_size = 0;
  85     packet_total_size = 0;
  86     nb_packets = 0;
  87     bit_rate = 0;
  88     duration = 0;
  89     for(i=0;i<ctx->nb_streams;i++) {
  90         StreamInfo *stream = &rm->streams[i];
  91         bit_rate += stream->bit_rate;
  92         if (stream->packet_max_size > packet_max_size)
  93             packet_max_size = stream->packet_max_size;
  94         nb_packets += stream->nb_packets;
  95         packet_total_size += stream->packet_total_size;
  96         /* select maximum duration */
  97         v = (int) (1000.0 * (float)stream->total_frames / stream->frame_rate);
  98         if (v > duration)
  99             duration = v;
 100     }
 101     put_be32(s, bit_rate); /* max bit rate */
 102     put_be32(s, bit_rate); /* avg bit rate */
 103     put_be32(s, packet_max_size);        /* max packet size */
 104     if (nb_packets > 0)
 105         packet_avg_size = packet_total_size / nb_packets;
 106     else
 107         packet_avg_size = 0;
 108     put_be32(s, packet_avg_size);        /* avg packet size */
 109     put_be32(s, nb_packets);  /* num packets */
 110     put_be32(s, duration); /* duration */
 111     put_be32(s, BUFFER_DURATION);           /* preroll */
 112     put_be32(s, index_pos);           /* index offset */
 113     /* computation of data the data offset */
 114     data_offset_ptr = s->buf_ptr;
 115     put_be32(s, 0);           /* data offset : will be patched after */
 116     put_be16(s, ctx->nb_streams);    /* num streams */
 117     flags = 1 | 2; /* save allowed & perfect play */
 118     if (url_is_streamed(s))
 119         flags |= 4; /* live broadcast */
 120     put_be16(s, flags);
 121
 122     /* comments */
 123
 124     put_tag(s,"CONT");
 125     size = strlen(ctx->title) + strlen(ctx->author) + strlen(ctx->copyright) +
 126         strlen(ctx->comment) + 4 * 2 + 10;
 127     put_be32(s,size);
 128     put_be16(s,0);
 129     put_str(s, ctx->title);
 130     put_str(s, ctx->author);
 131     put_str(s, ctx->copyright);
 132     put_str(s, ctx->comment);
 133
 134     for(i=0;i<ctx->nb_streams;i++) {
 135         int codec_data_size;
 136
 137         stream = &rm->streams[i];
 138
 139         if (stream->enc->codec_type == CODEC_TYPE_AUDIO) {
 140             desc = "The Audio Stream";
 141             mimetype = "audio/x-pn-realaudio";
 142             codec_data_size = 73;
 143         } else {
 144             desc = "The Video Stream";
 145             mimetype = "video/x-pn-realvideo";
 146             codec_data_size = 34;
 147         }
 148
 149         put_tag(s,"MDPR");
 150         size = 10 + 9 * 4 + strlen(desc) + strlen(mimetype) + codec_data_size;
 151         put_be32(s, size);
 152         put_be16(s, 0);
 153
 154         put_be16(s, i); /* stream number */
 155         put_be32(s, stream->bit_rate); /* max bit rate */
 156         put_be32(s, stream->bit_rate); /* avg bit rate */
 157         put_be32(s, stream->packet_max_size);        /* max packet size */
 158         if (stream->nb_packets > 0)
 159             packet_avg_size = stream->packet_total_size /
 160                 stream->nb_packets;
 161         else
 162             packet_avg_size = 0;
 163         put_be32(s, packet_avg_size);        /* avg packet size */
 164         put_be32(s, 0);           /* start time */
 165         put_be32(s, BUFFER_DURATION);           /* preroll */
 166         /* duration */
 167         if (url_is_streamed(s) || !stream->total_frames)
 168             put_be32(s, (int)(3600 * 1000));
 169         else
 170             put_be32(s, (int)(stream->total_frames * 1000 / stream->frame_rate));
 171         put_str8(s, desc);
 172         put_str8(s, mimetype);
 173         put_be32(s, codec_data_size);
 174
 175         if (stream->enc->codec_type == CODEC_TYPE_AUDIO) {
 176             int coded_frame_size, fscode, sample_rate;
 177             sample_rate = stream->enc->sample_rate;
 178             coded_frame_size = (stream->enc->bit_rate *
 179                                 stream->enc->frame_size) / (8 * sample_rate);
 180             /* audio codec info */
 181             put_tag(s, ".ra");
 182             put_byte(s, 0xfd);
 183             put_be32(s, 0x00040000); /* version */
 184             put_tag(s, ".ra4");
 185             put_be32(s, 0x01b53530); /* stream length */
 186             put_be16(s, 4); /* unknown */
 187             put_be32(s, 0x39); /* header size */
 188
 189             switch(sample_rate) {
 190             case 48000:
 191             case 24000:
 192             case 12000:
 193                 fscode = 1;
 194                 break;
 195             default:
 196             case 44100:
 197             case 22050:
 198             case 11025:
 199                 fscode = 2;
 200                 break;
 201             case 32000:
 202             case 16000:
 203             case 8000:
 204                 fscode = 3;
 205             }
 206             put_be16(s, fscode); /* codec additional info, for AC3, seems
 207                                      to be a frequency code */
 208             /* special hack to compensate rounding errors... */
 209             if (coded_frame_size == 557)
 210                 coded_frame_size--;
 211             put_be32(s, coded_frame_size); /* frame length */
 212             put_be32(s, 0x51540); /* unknown */
 213             put_be32(s, 0x249f0); /* unknown */
 214             put_be32(s, 0x249f0); /* unknown */
 215             put_be16(s, 0x01);
 216             /* frame length : seems to be very important */
 217             put_be16(s, coded_frame_size);
 218             put_be32(s, 0); /* unknown */
 219             put_be16(s, stream->enc->sample_rate); /* sample rate */
 220             put_be32(s, 0x10); /* unknown */
 221             put_be16(s, stream->enc->channels);
 222             put_str8(s, "Int0"); /* codec name */
 223             put_str8(s, "dnet"); /* codec name */
 224             put_be16(s, 0); /* title length */
 225             put_be16(s, 0); /* author length */
 226             put_be16(s, 0); /* copyright length */
 227             put_byte(s, 0); /* end of header */
 228         } else {
 229             /* video codec info */
 230             put_be32(s,34); /* size */
 231             put_tag(s,"VIDORV10");
 232             put_be16(s, stream->enc->width);
 233             put_be16(s, stream->enc->height);
 234             put_be16(s, (int) stream->frame_rate); /* frames per seconds ? */
 235             put_be32(s,0);     /* unknown meaning */
 236             put_be16(s, (int) stream->frame_rate);  /* unknown meaning */
 237             put_be32(s,0);     /* unknown meaning */
 238             put_be16(s, 8);    /* unknown meaning */
 239             /* Seems to be the codec version: only use basic H263. The next
 240                versions seems to add a diffential DC coding as in
 241                MPEG... nothing new under the sun */
 242             put_be32(s,0x10000000);
 243             //put_be32(s,0x10003000);
 244         }
 245     }
 246
 247     /* patch data offset field */
 248     data_pos = s->buf_ptr - start_ptr;
 249     rm->data_pos = data_pos;
 250     data_offset_ptr[0] = data_pos >> 24;
 251     data_offset_ptr[1] = data_pos >> 16;
 252     data_offset_ptr[2] = data_pos >> 8;
 253     data_offset_ptr[3] = data_pos;
 254
 255     /* data stream */
 256     put_tag(s,"DATA");
 257     put_be32(s,data_size + 10 + 8);
 258     put_be16(s,0);
 259
 260     put_be32(s, nb_packets); /* number of packets */
 261     put_be32(s,0); /* next data header */
 262 }
 263
 264 static void write_packet_header(AVFormatContext *ctx, StreamInfo *stream,
 265                                 int length, int key_frame)
 266 {
 267     int timestamp;
 268     ByteIOContext *s = &ctx->pb;
 269
 270     stream->nb_packets++;
 271     stream->packet_total_size += length;
 272     if (length > stream->packet_max_size)
 273         stream->packet_max_size =  length;
 274
 275     put_be16(s,0); /* version */
 276     put_be16(s,length + 12);
 277     put_be16(s, stream->num); /* stream number */
 278     timestamp = (1000 * (float)stream->nb_frames) / stream->frame_rate;
 279     put_be32(s, timestamp); /* timestamp */
 280     put_byte(s, 0); /* reserved */
 281     put_byte(s, key_frame ? 2 : 0); /* flags */
 282 }
 283
 284 static int rm_write_header(AVFormatContext *s)
 285 {
 286     RMContext *rm = s->priv_data;
 287     StreamInfo *stream;
 288     int n;
 289     AVCodecContext *codec;
 290
 291     for(n=0;n<s->nb_streams;n++) {
 292         s->streams[n]->id = n;
 293         codec = &s->streams[n]->codec;
 294         stream = &rm->streams[n];
 295         memset(stream, 0, sizeof(StreamInfo));
 296         stream->num = n;
 297         stream->bit_rate = codec->bit_rate;
 298         stream->enc = codec;
 299
 300         switch(codec->codec_type) {
 301         case CODEC_TYPE_AUDIO:
 302             rm->audio_stream = stream;
 303             stream->frame_rate = (float)codec->sample_rate / (float)codec->frame_size;
 304             /* XXX: dummy values */
 305             stream->packet_max_size = 1024;
 306             stream->nb_packets = 0;
 307             stream->total_frames = stream->nb_packets;
 308             break;
 309         case CODEC_TYPE_VIDEO:
 310             rm->video_stream = stream;
 311             stream->frame_rate = (float)codec->frame_rate / (float)codec->frame_rate_base;
 312             /* XXX: dummy values */
 313             stream->packet_max_size = 4096;
 314             stream->nb_packets = 0;
 315             stream->total_frames = stream->nb_packets;
 316             break;
 317         default:
 318             av_abort();
 319         }
 320     }
 321
 322     rv10_write_header(s, 0, 0);
 323     put_flush_packet(&s->pb);
 324     return 0;
 325 }
 326
 327 static int rm_write_audio(AVFormatContext *s, const uint8_t *buf, int size)
 328 {
 329     uint8_t *buf1;
 330     RMContext *rm = s->priv_data;
 331     ByteIOContext *pb = &s->pb;
 332     StreamInfo *stream = rm->audio_stream;
 333     int i;
 334
 335     /* XXX: suppress this malloc */
 336     buf1= (uint8_t*) av_malloc( size * sizeof(uint8_t) );
 337
 338     write_packet_header(s, stream, size, stream->enc->coded_frame->key_frame);
 339
 340     /* for AC3, the words seems to be reversed */
 341     for(i=0;i<size;i+=2) {
 342         buf1[i] = buf[i+1];
 343         buf1[i+1] = buf[i];
 344     }
 345     put_buffer(pb, buf1, size);
 346     put_flush_packet(pb);
 347     stream->nb_frames++;
 348     av_free(buf1);
 349     return 0;
 350 }
 351
 352 static int rm_write_video(AVFormatContext *s, const uint8_t *buf, int size)
 353 {
 354     RMContext *rm = s->priv_data;
 355     ByteIOContext *pb = &s->pb;
 356     StreamInfo *stream = rm->video_stream;
 357     int key_frame = stream->enc->coded_frame->key_frame;
 358
 359     /* XXX: this is incorrect: should be a parameter */
 360
 361     /* Well, I spent some time finding the meaning of these bits. I am
 362        not sure I understood everything, but it works !! */
 363 #if 1
 364     write_packet_header(s, stream, size + 7, key_frame);
 365     /* bit 7: '1' if final packet of a frame converted in several packets */
 366     put_byte(pb, 0x81);
 367     /* bit 7: '1' if I frame. bits 6..0 : sequence number in current
 368        frame starting from 1 */
 369     if (key_frame) {
 370         put_byte(pb, 0x81);
 371     } else {
 372         put_byte(pb, 0x01);
 373     }
 374     put_be16(pb, 0x4000 | (size)); /* total frame size */
 375     put_be16(pb, 0x4000 | (size));              /* offset from the start or the end */
 376 #else
 377     /* full frame */
 378     write_packet_header(s, size + 6);
 379     put_byte(pb, 0xc0);
 380     put_be16(pb, 0x4000 | size); /* total frame size */
 381     put_be16(pb, 0x4000 + packet_number * 126); /* position in stream */
 382 #endif
 383     put_byte(pb, stream->nb_frames & 0xff);
 384
 385     put_buffer(pb, buf, size);
 386     put_flush_packet(pb);
 387
 388     stream->nb_frames++;
 389     return 0;
 390 }
 391
 392 static int rm_write_packet(AVFormatContext *s, int stream_index,
 393                            const uint8_t *buf, int size, int64_t pts)
 394 {
 395     if (s->streams[stream_index]->codec.codec_type ==
 396         CODEC_TYPE_AUDIO)
 397         return rm_write_audio(s, buf, size);
 398     else
 399         return rm_write_video(s, buf, size);
 400 }
 401
 402 static int rm_write_trailer(AVFormatContext *s)
 403 {
 404     RMContext *rm = s->priv_data;
 405     int data_size, index_pos, i;
 406     ByteIOContext *pb = &s->pb;
 407
 408     if (!url_is_streamed(&s->pb)) {
 409         /* end of file: finish to write header */
 410         index_pos = url_fseek(pb, 0, SEEK_CUR);
 411         data_size = index_pos - rm->data_pos;
 412
 413         /* index */
 414         put_tag(pb, "INDX");
 415         put_be32(pb, 10 + 10 * s->nb_streams);
 416         put_be16(pb, 0);
 417
 418         for(i=0;i<s->nb_streams;i++) {
 419             put_be32(pb, 0); /* zero indices */
 420             put_be16(pb, i); /* stream number */
 421             put_be32(pb, 0); /* next index */
 422         }
 423         /* undocumented end header */
 424         put_be32(pb, 0);
 425         put_be32(pb, 0);
 426
 427         url_fseek(pb, 0, SEEK_SET);
 428         for(i=0;i<s->nb_streams;i++)
 429             rm->streams[i].total_frames = rm->streams[i].nb_frames;
 430         rv10_write_header(s, data_size, index_pos);
 431     } else {
 432         /* undocumented end header */
 433         put_be32(pb, 0);
 434         put_be32(pb, 0);
 435     }
 436     put_flush_packet(pb);
 437     return 0;
 438 }
 439 #endif //CONFIG_ENCODERS
 440
 441 /***************************************************/
 442
 443 static void get_str(ByteIOContext *pb, char *buf, int buf_size)
 444 {
 445     int len, i;
 446     char *q;
 447
 448     len = get_be16(pb);
 449     q = buf;
 450     for(i=0;i<len;i++) {
 451         if (i < buf_size - 1)
 452             *q++ = get_byte(pb);
 453     }
 454     *q = '\0';
 455 }
 456
 457 static void get_str8(ByteIOContext *pb, char *buf, int buf_size)
 458 {
 459     int len, i;
 460     char *q;
 461
 462     len = get_byte(pb);
 463     q = buf;
 464     for(i=0;i<len;i++) {
 465         if (i < buf_size - 1)
 466             *q++ = get_byte(pb);
 467     }
 468     *q = '\0';
 469 }
 470
 471 static void rm_read_audio_stream_info(AVFormatContext *s, AVStream *st,
 472                                       int read_all)
 473 {
 474     ByteIOContext *pb = &s->pb;
 475     char buf[128];
 476     uint32_t version;
 477     int i;
 478
 479     /* ra type header */
 480     version = get_be32(pb); /* version */
 481     if (((version >> 16) & 0xff) == 3) {
 482         /* very old version */
 483         for(i = 0; i < 14; i++)
 484             get_byte(pb);
 485         get_str8(pb, s->title, sizeof(s->title));
 486         get_str8(pb, s->author, sizeof(s->author));
 487         get_str8(pb, s->copyright, sizeof(s->copyright));
 488         get_str8(pb, s->comment, sizeof(s->comment));
 489         get_byte(pb);
 490         get_str8(pb, buf, sizeof(buf));
 491         st->codec.sample_rate = 8000;
 492         st->codec.channels = 1;
 493         st->codec.codec_type = CODEC_TYPE_AUDIO;
 494         st->codec.codec_id = CODEC_ID_RA_144;
 495     } else {
 496         /* old version (4) */
 497         get_be32(pb); /* .ra4 */
 498         get_be32(pb);
 499         get_be16(pb);
 500         get_be32(pb); /* header size */
 501         get_be16(pb); /* add codec info */
 502         get_be32(pb); /* coded frame size */
 503         get_be32(pb); /* ??? */
 504         get_be32(pb); /* ??? */
 505         get_be32(pb); /* ??? */
 506         get_be16(pb); /* 1 */
 507         get_be16(pb); /* coded frame size */
 508         get_be32(pb);
 509         st->codec.sample_rate = get_be16(pb);
 510         get_be32(pb);
 511         st->codec.channels = get_be16(pb);
 512         get_str8(pb, buf, sizeof(buf)); /* desc */
 513         get_str8(pb, buf, sizeof(buf)); /* desc */
 514         st->codec.codec_type = CODEC_TYPE_AUDIO;
 515         if (!strcmp(buf, "dnet")) {
 516             st->codec.codec_id = CODEC_ID_AC3;
 517         } else {
 518             st->codec.codec_id = CODEC_ID_NONE;
 519             pstrcpy(st->codec.codec_name, sizeof(st->codec.codec_name),
 520                     buf);
 521         }
 522         if (read_all) {
 523             get_byte(pb);
 524             get_byte(pb);
 525             get_byte(pb);
 526
 527             get_str8(pb, s->title, sizeof(s->title));
 528             get_str8(pb, s->author, sizeof(s->author));
 529             get_str8(pb, s->copyright, sizeof(s->copyright));
 530             get_str8(pb, s->comment, sizeof(s->comment));
 531         }
 532     }
 533 }
 534
 535 static int rm_read_header_old(AVFormatContext *s, AVFormatParameters *ap)
 536 {
 537     RMContext *rm = s->priv_data;
 538     AVStream *st;
 539
 540     rm->old_format = 1;
 541     st = av_new_stream(s, 0);
 542     if (!st)
 543         goto fail;
 544     rm_read_audio_stream_info(s, st, 1);
 545     return 0;
 546  fail:
 547     return -1;
 548 }
 549
 550 static int rm_read_header(AVFormatContext *s, AVFormatParameters *ap)
 551 {
 552     RMContext *rm = s->priv_data;
 553     AVStream *st;
 554     ByteIOContext *pb = &s->pb;
 555     unsigned int tag, v;
 556     int tag_size, size, codec_data_size, i;
 557     int64_t codec_pos;
 558     unsigned int h263_hack_version, start_time, duration;
 559     char buf[128];
 560     int flags = 0;
 561
 562     tag = get_le32(pb);
 563     if (tag == MKTAG('.', 'r', 'a', 0xfd)) {
 564         /* very old .ra format */
 565         return rm_read_header_old(s, ap);
 566     } else if (tag != MKTAG('.', 'R', 'M', 'F')) {
 567         return -EIO;
 568     }
 569
 570     get_be32(pb); /* header size */
 571     get_be16(pb);
 572     get_be32(pb);
 573     get_be32(pb); /* number of headers */
 574
 575     for(;;) {
 576         if (url_feof(pb))
 577             goto fail;
 578         tag = get_le32(pb);
 579         tag_size = get_be32(pb);
 580         get_be16(pb);
 581 #if 0
 582         printf("tag=%c%c%c%c (%08x) size=%d\n",
 583                (tag) & 0xff,
 584                (tag >> 8) & 0xff,
 585                (tag >> 16) & 0xff,
 586                (tag >> 24) & 0xff,
 587                tag,
 588                tag_size);
 589 #endif
 590         if (tag_size < 10)
 591             goto fail;
 592         switch(tag) {
 593         case MKTAG('P', 'R', 'O', 'P'):
 594             /* file header */
 595             get_be32(pb); /* max bit rate */
 596             get_be32(pb); /* avg bit rate */
 597             get_be32(pb); /* max packet size */
 598             get_be32(pb); /* avg packet size */
 599             get_be32(pb); /* nb packets */
 600             get_be32(pb); /* duration */
 601             get_be32(pb); /* preroll */
 602             get_be32(pb); /* index offset */
 603             get_be32(pb); /* data offset */
 604             get_be16(pb); /* nb streams */
 605             flags = get_be16(pb); /* flags */
 606             break;
 607         case MKTAG('C', 'O', 'N', 'T'):
 608             get_str(pb, s->title, sizeof(s->title));
 609             get_str(pb, s->author, sizeof(s->author));
 610             get_str(pb, s->copyright, sizeof(s->copyright));
 611             get_str(pb, s->comment, sizeof(s->comment));
 612             break;
 613         case MKTAG('M', 'D', 'P', 'R'):
 614             st = av_new_stream(s, 0);
 615             if (!st)
 616                 goto fail;
 617             st->id = get_be16(pb);
 618             get_be32(pb); /* max bit rate */
 619             st->codec.bit_rate = get_be32(pb); /* bit rate */
 620             get_be32(pb); /* max packet size */
 621             get_be32(pb); /* avg packet size */
 622             start_time = get_be32(pb); /* start time */
 623             get_be32(pb); /* preroll */
 624             duration = get_be32(pb); /* duration */
 625             st->start_time = start_time * (AV_TIME_BASE / 1000);
 626             st->duration = duration * (AV_TIME_BASE / 1000);
 627             get_str8(pb, buf, sizeof(buf)); /* desc */
 628             get_str8(pb, buf, sizeof(buf)); /* mimetype */
 629             codec_data_size = get_be32(pb);
 630             codec_pos = url_ftell(pb);
 631
 632             v = get_be32(pb);
 633             if (v == MKTAG(0xfd, 'a', 'r', '.')) {
 634                 /* ra type header */
 635                 rm_read_audio_stream_info(s, st, 0);
 636             } else {
 637                 if (get_le32(pb) != MKTAG('V', 'I', 'D', 'O')) {
 638                 fail1:
 639                     av_log(&st->codec, AV_LOG_ERROR, "Unsupported video codec\n");
 640                     goto fail;
 641                 }
 642                 st->codec.codec_tag = get_le32(pb);
 643                 if (st->codec.codec_tag != MKTAG('R', 'V', '1', '0'))
 644                     goto fail1;
 645                 st->codec.width = get_be16(pb);
 646                 st->codec.height = get_be16(pb);
 647                 st->codec.frame_rate_base= 1;
 648                 st->codec.frame_rate = get_be16(pb) * st->codec.frame_rate_base;
 649                 st->codec.codec_type = CODEC_TYPE_VIDEO;
 650                 get_be32(pb);
 651                 get_be16(pb);
 652                 get_be32(pb);
 653                 get_be16(pb);
 654                 /* modification of h263 codec version (!) */
 655                 h263_hack_version = get_be32(pb);
 656                 switch(h263_hack_version) {
 657                 case 0x10000000:
 658                 case 0x10003000:
 659                 case 0x10003001:
 660                     st->codec.sub_id = h263_hack_version;
 661                     st->codec.codec_id = CODEC_ID_RV10;
 662                     break;
 663                 default:
 664                     /* not handled */
 665                     st->codec.codec_id = CODEC_ID_NONE;
 666                     break;
 667                 }
 668             }
 669             /* skip codec info */
 670             size = url_ftell(pb) - codec_pos;
 671             url_fskip(pb, codec_data_size - size);
 672             break;
 673         case MKTAG('D', 'A', 'T', 'A'):
 674             goto header_end;
 675         default:
 676             /* unknown tag: skip it */
 677             url_fskip(pb, tag_size - 10);
 678             break;
 679         }
 680     }
 681  header_end:
 682     rm->nb_packets = get_be32(pb); /* number of packets */
 683     if (!rm->nb_packets && (flags & 4))
 684         rm->nb_packets = 3600 * 25;
 685     get_be32(pb); /* next data header */
 686     return 0;
 687
 688  fail:
 689     for(i=0;i<s->nb_streams;i++) {
 690         av_free(s->streams[i]);
 691     }
 692     return -EIO;
 693 }
 694
 695 static int get_num(ByteIOContext *pb, int *len)
 696 {
 697     int n, n1;
 698
 699     n = get_be16(pb);
 700     (*len)-=2;
 701     if (n >= 0x4000) {
 702         return n - 0x4000;
 703     } else {
 704         n1 = get_be16(pb);
 705         (*len)-=2;
 706         return (n << 16) | n1;
 707     }
 708 }
 709
 710 /* multiple of 20 bytes for ra144 (ugly) */
 711 #define RAW_PACKET_SIZE 1000
 712
 713 static int rm_read_packet(AVFormatContext *s, AVPacket *pkt)
 714 {
 715     RMContext *rm = s->priv_data;
 716     ByteIOContext *pb = &s->pb;
 717     AVStream *st;
 718     int len, num, timestamp, i, tmp, j;
 719     uint8_t *ptr;
 720     int flags;
 721
 722     if (rm->old_format) {
 723         /* just read raw bytes */
 724         len = RAW_PACKET_SIZE;
 725         av_new_packet(pkt, len);
 726         pkt->stream_index = 0;
 727         len = get_buffer(pb, pkt->data, len);
 728         if (len <= 0) {
 729             av_free_packet(pkt);
 730             return -EIO;
 731         }
 732         pkt->size = len;
 733         st = s->streams[0];
 734     } else {
 735     redo:
 736         if (rm->nb_packets == 0)
 737             return -EIO;
 738         get_be16(pb);
 739         len = get_be16(pb);
 740         if (len < 12)
 741             return -EIO;
 742         num = get_be16(pb);
 743         timestamp = get_be32(pb);
 744         get_byte(pb); /* reserved */
 745         flags = get_byte(pb); /* flags */
 746         rm->nb_packets--;
 747         len -= 12;
 748
 749         st = NULL;
 750         for(i=0;i<s->nb_streams;i++) {
 751             st = s->streams[i];
 752             if (num == st->id)
 753                 break;
 754         }
 755         if (i == s->nb_streams) {
 756             /* skip packet if unknown number */
 757             url_fskip(pb, len);
 758             goto redo;
 759         }
 760
 761         if (st->codec.codec_type == CODEC_TYPE_VIDEO) {
 762             int full_frame, h, pic_num;
 763
 764             h= get_byte(pb);
 765             if ((h & 0xc0) == 0xc0) {
 766                 int len2, pos;
 767                 full_frame = 1;
 768                 len2= get_num(pb, &len);
 769                 pos = get_num(pb, &len);
 770                 //printf("pos:%d\n",len);
 771                 len -= 2;
 772             } else {
 773                 int seq, frame_size, pos;
 774                 full_frame = 0;
 775                 seq = get_byte(pb);
 776                 frame_size = get_num(pb, &len);
 777                 pos = get_num(pb, &len);
 778                 //printf("seq:%d, size:%d, pos:%d\n",seq,frame_size,pos);
 779                 len -= 3;
 780             }
 781             /* picture number */
 782             pic_num= get_byte(pb);
 783
 784             //XXX/FIXME/HACK, demuxer should be fixed to send complete frames ...
 785             if(st->codec.slice_offset==NULL)
 786                 st->codec.slice_offset= (int*)av_malloc(sizeof(int));
 787             st->codec.slice_count= full_frame;
 788             st->codec.slice_offset[0]= 0;
 789         }
 790
 791         av_new_packet(pkt, len);
 792         pkt->stream_index = i;
 793         get_buffer(pb, pkt->data, len);
 794     }
 795
 796     /* for AC3, needs to swap bytes */
 797     if (st->codec.codec_id == CODEC_ID_AC3) {
 798         ptr = pkt->data;
 799         for(j=0;j<len;j+=2) {
 800             tmp = ptr[0];
 801             ptr[0] = ptr[1];
 802             ptr[1] = tmp;
 803                 ptr += 2;
 804         }
 805     }
 806     return 0;
 807 }
 808
 809 static int rm_read_close(AVFormatContext *s)
 810 {
 811     return 0;
 812 }
 813
 814 static int rm_probe(AVProbeData *p)
 815 {
 816     /* check file header */
 817     if (p->buf_size <= 32)
 818         return 0;
 819     if ((p->buf[0] == '.' && p->buf[1] == 'R' &&
 820          p->buf[2] == 'M' && p->buf[3] == 'F' &&
 821          p->buf[4] == 0 && p->buf[5] == 0) ||
 822         (p->buf[0] == '.' && p->buf[1] == 'r' &&
 823          p->buf[2] == 'a' && p->buf[3] == 0xfd))
 824         return AVPROBE_SCORE_MAX;
 825     else
 826         return 0;
 827 }
 828
 829 static AVInputFormat rm_iformat = {
 830     "rm",
 831     "rm format",
 832     sizeof(RMContext),
 833     rm_probe,
 834     rm_read_header,
 835     rm_read_packet,
 836     rm_read_close,
 837 };
 838
 839 #ifdef CONFIG_ENCODERS
 840 static AVOutputFormat rm_oformat = {
 841     "rm",
 842     "rm format",
 843     "application/vnd.rn-realmedia",
 844     "rm,ra",
 845     sizeof(RMContext),
 846     CODEC_ID_AC3,
 847     CODEC_ID_RV10,
 848     rm_write_header,
 849     rm_write_packet,
 850     rm_write_trailer,
 851 };
 852 #endif //CONFIG_ENCODERS
 853
 854 int rm_init(void)
 855 {
 856     av_register_input_format(&rm_iformat);
 857 #ifdef CONFIG_ENCODERS
 858     av_register_output_format(&rm_oformat);
 859 #endif //CONFIG_ENCODERS
 860     return 0;
 861 }