libavformat/asf.c

   1 /*
   2  * ASF 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 "riff.h"
  23 #include "mpegaudio.h"
  24 #include "asf.h"
  25 #include "common.h"
  26 #include "asfcrypt.h"
  27
  28 extern void ff_mms_set_stream_selection(URLContext *h, AVFormatContext *format);
  29
  30 #undef NDEBUG
  31 #include <assert.h>
  32
  33 #define FRAME_HEADER_SIZE 17
  34 // Fix Me! FRAME_HEADER_SIZE may be different.
  35
  36 static const GUID index_guid = {
  37     0x90, 0x08, 0x00, 0x33, 0xb1, 0xe5, 0xcf, 0x11, 0x89, 0xf4, 0x00, 0xa0, 0xc9, 0x03, 0x49, 0xcb
  38 };
  39
  40 static const GUID stream_bitrate_guid = { /* (http://get.to/sdp) */
  41     0xce, 0x75, 0xf8, 0x7b, 0x8d, 0x46, 0xd1, 0x11, 0x8d, 0x82, 0x00, 0x60, 0x97, 0xc9, 0xa2, 0xb2
  42 };
  43 /**********************************/
  44 /* decoding */
  45
  46 //#define DEBUG
  47
  48 #ifdef DEBUG
  49 #define PRINT_IF_GUID(g,cmp) \
  50 if (!memcmp(g, &cmp, sizeof(GUID))) \
  51     printf("(GUID: %s) ", #cmp)
  52
  53 static void print_guid(const GUID *g)
  54 {
  55     int i;
  56     PRINT_IF_GUID(g, asf_header);
  57     else PRINT_IF_GUID(g, file_header);
  58     else PRINT_IF_GUID(g, stream_header);
  59     else PRINT_IF_GUID(g, audio_stream);
  60     else PRINT_IF_GUID(g, audio_conceal_none);
  61     else PRINT_IF_GUID(g, video_stream);
  62     else PRINT_IF_GUID(g, video_conceal_none);
  63     else PRINT_IF_GUID(g, command_stream);
  64     else PRINT_IF_GUID(g, comment_header);
  65     else PRINT_IF_GUID(g, codec_comment_header);
  66     else PRINT_IF_GUID(g, codec_comment1_header);
  67     else PRINT_IF_GUID(g, data_header);
  68     else PRINT_IF_GUID(g, index_guid);
  69     else PRINT_IF_GUID(g, head1_guid);
  70     else PRINT_IF_GUID(g, head2_guid);
  71     else PRINT_IF_GUID(g, my_guid);
  72     else PRINT_IF_GUID(g, ext_stream_header);
  73     else PRINT_IF_GUID(g, extended_content_header);
  74     else PRINT_IF_GUID(g, ext_stream_embed_stream_header);
  75     else PRINT_IF_GUID(g, ext_stream_audio_stream);
  76     else PRINT_IF_GUID(g, metadata_header);
  77     else PRINT_IF_GUID(g, stream_bitrate_guid);
  78     else
  79         printf("(GUID: unknown) ");
  80     for(i=0;i<16;i++)
  81         printf(" 0x%02x,", (*g)[i]);
  82     printf("}\n");
  83 }
  84 #undef PRINT_IF_GUID
  85 #endif
  86
  87 static void get_guid(ByteIOContext *s, GUID *g)
  88 {
  89     assert(sizeof(*g) == 16);
  90     get_buffer(s, g, sizeof(*g));
  91 }
  92
  93 #if 0
  94 static void get_str16(ByteIOContext *pb, char *buf, int buf_size)
  95 {
  96     int len, c;
  97     char *q;
  98
  99     len = get_le16(pb);
 100     q = buf;
 101     while (len > 0) {
 102         c = get_le16(pb);
 103         if ((q - buf) < buf_size - 1)
 104             *q++ = c;
 105         len--;
 106     }
 107     *q = '\0';
 108 }
 109 #endif
 110
 111 static int is_mms(ByteIOContext *pb)
 112 {
 113     return url_fileno(pb) && url_fileno(pb)->prot &&
 114          !strcmp(url_fileno(pb)->prot->name, "mmsh");
 115 }
 116
 117 static void get_str16_nolen(ByteIOContext *pb, int len, char *buf, int buf_size)
 118 {
 119     char* q = buf;
 120     len /= 2;
 121     while (len--) {
 122         uint8_t tmp;
 123         PUT_UTF8(get_le16(pb), tmp, if (q - buf < buf_size - 1) *q++ = tmp;)
 124     }
 125     *q = '\0';
 126 }
 127
 128 static int asf_probe(AVProbeData *pd)
 129 {
 130     /* check file header */
 131     if (!memcmp(pd->buf, &asf_header, sizeof(GUID)))
 132         return AVPROBE_SCORE_MAX;
 133     else
 134         return 0;
 135 }
 136
 137 static int get_value(ByteIOContext *pb, int type){
 138     switch(type){
 139         case 2: return get_le32(pb);
 140         case 3: return get_le32(pb);
 141         case 4: return get_le64(pb);
 142         case 5: return get_le16(pb);
 143         default:return INT_MIN;
 144     }
 145 }
 146
 147 static int asf_read_header(AVFormatContext *s, AVFormatParameters *ap)
 148 {
 149     ASFContext *asf = s->priv_data;
 150     GUID g;
 151     ByteIOContext *pb = s->pb;
 152     AVStream *st;
 153     ASFStream *asf_st;
 154     int size, i;
 155     int64_t gsize;
 156     AVRational dar[128];
 157     uint32_t bitrate[128];
 158
 159     memset(dar, 0, sizeof(dar));
 160     memset(bitrate, 0, sizeof(bitrate));
 161
 162     get_guid(pb, &g);
 163     if (memcmp(&g, &asf_header, sizeof(GUID)))
 164         goto fail;
 165     get_le64(pb);
 166     get_le32(pb);
 167     get_byte(pb);
 168     get_byte(pb);
 169     memset(&asf->asfid2avid, -1, sizeof(asf->asfid2avid));
 170     for(;;) {
 171         get_guid(pb, &g);
 172         gsize = get_le64(pb);
 173 #ifdef DEBUG
 174         printf("%08"PRIx64": ", url_ftell(pb) - 24);
 175         print_guid(&g);
 176         printf("  size=0x%"PRIx64"\n", gsize);
 177 #endif
 178         if (!memcmp(&g, &data_header, sizeof(GUID))) {
 179             asf->data_object_offset = url_ftell(pb);
 180             // if not streaming, gsize is not unlimited (how?), and there is enough space in the file..
 181             if (!(asf->hdr.flags & 0x01) && gsize >= 100) {
 182                 asf->data_object_size = gsize - 24;
 183             } else {
 184                 asf->data_object_size = (uint64_t)-1;
 185             }
 186             break;
 187         }
 188         if (gsize < 24)
 189             goto fail;
 190         if (!memcmp(&g, &file_header, sizeof(GUID))) {
 191             get_guid(pb, &asf->hdr.guid);
 192             asf->hdr.file_size          = get_le64(pb);
 193             asf->hdr.create_time        = get_le64(pb);
 194             asf->nb_packets             = get_le64(pb);
 195             asf->hdr.send_time          = get_le64(pb);
 196             asf->hdr.play_time          = get_le64(pb);
 197             asf->hdr.preroll            = get_le32(pb);
 198             asf->hdr.ignore             = get_le32(pb);
 199             asf->hdr.flags              = get_le32(pb);
 200             asf->hdr.min_pktsize        = get_le32(pb);
 201             asf->hdr.max_pktsize        = get_le32(pb);
 202             asf->hdr.max_bitrate        = get_le32(pb);
 203             asf->packet_size = asf->hdr.max_pktsize;
 204         } else if (!memcmp(&g, &stream_header, sizeof(GUID))) {
 205             int type, type_specific_size, sizeX;
 206             uint64_t total_size;
 207             unsigned int tag1;
 208             int64_t pos1, pos2, start_time;
 209             int test_for_ext_stream_audio, is_dvr_ms_audio=0;
 210
 211             pos1 = url_ftell(pb);
 212
 213             st = av_new_stream(s, 0);
 214             if (!st)
 215                 goto fail;
 216             av_set_pts_info(st, 32, 1, 1000); /* 32 bit pts in ms */
 217             asf_st = av_mallocz(sizeof(ASFStream));
 218             if (!asf_st)
 219                 goto fail;
 220             st->priv_data = asf_st;
 221             start_time = asf->hdr.preroll;
 222
 223             if(!(asf->hdr.flags & 0x01)) { // if we aren't streaming...
 224                 st->duration = asf->hdr.send_time /
 225                     (10000000 / 1000) - start_time;
 226             }
 227             get_guid(pb, &g);
 228
 229             test_for_ext_stream_audio = 0;
 230             if (!memcmp(&g, &audio_stream, sizeof(GUID))) {
 231                 type = CODEC_TYPE_AUDIO;
 232             } else if (!memcmp(&g, &video_stream, sizeof(GUID))) {
 233                 type = CODEC_TYPE_VIDEO;
 234             } else if (!memcmp(&g, &command_stream, sizeof(GUID))) {
 235                 type = CODEC_TYPE_UNKNOWN;
 236             } else if (!memcmp(&g, &ext_stream_embed_stream_header, sizeof(GUID))) {
 237                 test_for_ext_stream_audio = 1;
 238                 type = CODEC_TYPE_UNKNOWN;
 239             } else {
 240                 goto fail;
 241             }
 242             get_guid(pb, &g);
 243             total_size = get_le64(pb);
 244             type_specific_size = get_le32(pb);
 245             get_le32(pb);
 246             st->id = get_le16(pb) & 0x7f; /* stream id */
 247             // mapping of asf ID to AV stream ID;
 248             asf->asfid2avid[st->id] = s->nb_streams - 1;
 249
 250             get_le32(pb);
 251
 252             if (test_for_ext_stream_audio) {
 253                 get_guid(pb, &g);
 254                 if (!memcmp(&g, &ext_stream_audio_stream, sizeof(GUID))) {
 255                     type = CODEC_TYPE_AUDIO;
 256                     is_dvr_ms_audio=1;
 257                     get_guid(pb, &g);
 258                     get_le32(pb);
 259                     get_le32(pb);
 260                     get_le32(pb);
 261                     get_guid(pb, &g);
 262                     get_le32(pb);
 263                 }
 264             }
 265
 266             st->codec->codec_type = type;
 267             if (type == CODEC_TYPE_AUDIO) {
 268                 get_wav_header(pb, st->codec, type_specific_size);
 269                 if (is_dvr_ms_audio) {
 270                     // codec_id and codec_tag are unreliable in dvr_ms
 271                     // files. Set them later by probing stream.
 272                     st->codec->codec_id = CODEC_ID_NONE;
 273                     st->codec->codec_tag = 0;
 274                 }
 275                 st->need_parsing = AVSTREAM_PARSE_FULL;
 276                 /* We have to init the frame size at some point .... */
 277                 pos2 = url_ftell(pb);
 278                 if (gsize >= (pos2 + 8 - pos1 + 24)) {
 279                     asf_st->ds_span = get_byte(pb);
 280                     asf_st->ds_packet_size = get_le16(pb);
 281                     asf_st->ds_chunk_size = get_le16(pb);
 282                     get_le16(pb); //ds_data_size
 283                     get_byte(pb); //ds_silence_data
 284                 }
 285                 //printf("Descrambling: ps:%d cs:%d ds:%d s:%d  sd:%d\n",
 286                 //       asf_st->ds_packet_size, asf_st->ds_chunk_size,
 287                 //       asf_st->ds_data_size, asf_st->ds_span, asf_st->ds_silence_data);
 288                 if (asf_st->ds_span > 1) {
 289                     if (!asf_st->ds_chunk_size
 290                         || (asf_st->ds_packet_size/asf_st->ds_chunk_size <= 1)
 291                         || asf_st->ds_packet_size % asf_st->ds_chunk_size)
 292                         asf_st->ds_span = 0; // disable descrambling
 293                 }
 294                 switch (st->codec->codec_id) {
 295                 case CODEC_ID_MP3:
 296                     st->codec->frame_size = MPA_FRAME_SIZE;
 297                     break;
 298                 case CODEC_ID_PCM_S16LE:
 299                 case CODEC_ID_PCM_S16BE:
 300                 case CODEC_ID_PCM_U16LE:
 301                 case CODEC_ID_PCM_U16BE:
 302                 case CODEC_ID_PCM_S8:
 303                 case CODEC_ID_PCM_U8:
 304                 case CODEC_ID_PCM_ALAW:
 305                 case CODEC_ID_PCM_MULAW:
 306                     st->codec->frame_size = 1;
 307                     break;
 308                 default:
 309                     /* This is probably wrong, but it prevents a crash later */
 310                     st->codec->frame_size = 1;
 311                     break;
 312                 }
 313             } else if (type == CODEC_TYPE_VIDEO) {
 314                 get_le32(pb);
 315                 get_le32(pb);
 316                 get_byte(pb);
 317                 size = get_le16(pb); /* size */
 318                 sizeX= get_le32(pb); /* size */
 319                 st->codec->width = get_le32(pb);
 320                 st->codec->height = get_le32(pb);
 321                 /* not available for asf */
 322                 get_le16(pb); /* panes */
 323                 st->codec->bits_per_sample = get_le16(pb); /* depth */
 324                 tag1 = get_le32(pb);
 325                 url_fskip(pb, 20);
 326 //                av_log(NULL, AV_LOG_DEBUG, "size:%d tsize:%d sizeX:%d\n", size, total_size, sizeX);
 327                 size= sizeX;
 328                 if (size > 40) {
 329                     st->codec->extradata_size = size - 40;
 330                     st->codec->extradata = av_mallocz(st->codec->extradata_size + FF_INPUT_BUFFER_PADDING_SIZE);
 331                     get_buffer(pb, st->codec->extradata, st->codec->extradata_size);
 332                 }
 333
 334         /* Extract palette from extradata if bpp <= 8 */
 335         /* This code assumes that extradata contains only palette */
 336         /* This is true for all paletted codecs implemented in ffmpeg */
 337         if (st->codec->extradata_size && (st->codec->bits_per_sample <= 8)) {
 338             st->codec->palctrl = av_mallocz(sizeof(AVPaletteControl));
 339 #ifdef WORDS_BIGENDIAN
 340             for (i = 0; i < FFMIN(st->codec->extradata_size, AVPALETTE_SIZE)/4; i++)
 341                 st->codec->palctrl->palette[i] = bswap_32(((uint32_t*)st->codec->extradata)[i]);
 342 #else
 343             memcpy(st->codec->palctrl->palette, st->codec->extradata,
 344                    FFMIN(st->codec->extradata_size, AVPALETTE_SIZE));
 345 #endif
 346             st->codec->palctrl->palette_changed = 1;
 347         }
 348
 349                 st->codec->codec_tag = tag1;
 350                 st->codec->codec_id = codec_get_id(codec_bmp_tags, tag1);
 351                 if(tag1 == MKTAG('D', 'V', 'R', ' '))
 352                     st->need_parsing = AVSTREAM_PARSE_FULL;
 353             }
 354             pos2 = url_ftell(pb);
 355             url_fskip(pb, gsize - (pos2 - pos1 + 24));
 356         } else if (!memcmp(&g, &comment_header, sizeof(GUID))) {
 357             int len1, len2, len3, len4, len5;
 358
 359             len1 = get_le16(pb);
 360             len2 = get_le16(pb);
 361             len3 = get_le16(pb);
 362             len4 = get_le16(pb);
 363             len5 = get_le16(pb);
 364             get_str16_nolen(pb, len1, s->title    , sizeof(s->title));
 365             get_str16_nolen(pb, len2, s->author   , sizeof(s->author));
 366             get_str16_nolen(pb, len3, s->copyright, sizeof(s->copyright));
 367             get_str16_nolen(pb, len4, s->comment  , sizeof(s->comment));
 368             url_fskip(pb, len5);
 369         } else if (!memcmp(&g, &stream_bitrate_guid, sizeof(GUID))) {
 370             int stream_count = get_le16(pb);
 371             int j;
 372
 373 //            av_log(NULL, AV_LOG_ERROR, "stream bitrate properties\n");
 374 //            av_log(NULL, AV_LOG_ERROR, "streams %d\n", streams);
 375             for(j = 0; j < stream_count; j++) {
 376                 int flags, bitrate, stream_id;
 377
 378                 flags= get_le16(pb);
 379                 bitrate= get_le32(pb);
 380                 stream_id= (flags & 0x7f);
 381 //                av_log(NULL, AV_LOG_ERROR, "flags: 0x%x stream id %d, bitrate %d\n", flags, stream_id, bitrate);
 382                 asf->stream_bitrates[stream_id]= bitrate;
 383             }
 384        } else if (!memcmp(&g, &extended_content_header, sizeof(GUID))) {
 385                 int desc_count, i;
 386
 387                 desc_count = get_le16(pb);
 388                 for(i=0;i<desc_count;i++)
 389                 {
 390                         int name_len,value_type,value_len;
 391                         uint64_t value_num = 0;
 392                         char name[1024];
 393
 394                         name_len = get_le16(pb);
 395                         get_str16_nolen(pb, name_len, name, sizeof(name));
 396                         value_type = get_le16(pb);
 397                         value_len = get_le16(pb);
 398                         if ((value_type == 0) || (value_type == 1)) // unicode or byte
 399                         {
 400                                 if     (!strcmp(name,"WM/AlbumTitle")) get_str16_nolen(pb, value_len, s->album, sizeof(s->album));
 401                                 else if(!strcmp(name,"WM/Genre"     )) get_str16_nolen(pb, value_len, s->genre, sizeof(s->genre));
 402                                 else if(!strcmp(name,"WM/Year"      )) {
 403                                     char year[8];
 404                                     get_str16_nolen(pb, value_len, year, sizeof(year));
 405                                     s->year = atoi(year);
 406                                 }
 407                                 else if(!strcmp(name,"WM/Track") && s->track == 0) {
 408                                     char track[8];
 409                                     get_str16_nolen(pb, value_len, track, sizeof(track));
 410                                     s->track = strtol(track, NULL, 10) + 1;
 411                                 }
 412                                 else if(!strcmp(name,"WM/TrackNumber")) {
 413                                     char track[8];
 414                                     get_str16_nolen(pb, value_len, track, sizeof(track));
 415                                     s->track = strtol(track, NULL, 10);
 416                                 }
 417                                 else url_fskip(pb, value_len);
 418                         }
 419                         if ((value_type >= 2) && (value_type <= 5)) // boolean or DWORD or QWORD or WORD
 420                         {
 421                                 value_num= get_value(pb, value_type);
 422                                 if (!strcmp(name,"WM/Track"      ) && s->track == 0) s->track = value_num + 1;
 423                                 if (!strcmp(name,"WM/TrackNumber")) s->track = value_num;
 424                         }
 425                 }
 426         } else if (!memcmp(&g, &metadata_header, sizeof(GUID))) {
 427             int n, stream_num, name_len, value_len, value_type, value_num;
 428             n = get_le16(pb);
 429
 430             for(i=0;i<n;i++) {
 431                 char name[1024];
 432
 433                 get_le16(pb); //lang_list_index
 434                 stream_num= get_le16(pb);
 435                 name_len=   get_le16(pb);
 436                 value_type= get_le16(pb);
 437                 value_len=  get_le32(pb);
 438
 439                 get_str16_nolen(pb, name_len, name, sizeof(name));
 440 //av_log(NULL, AV_LOG_ERROR, "%d %d %d %d %d <%s>\n", i, stream_num, name_len, value_type, value_len, name);
 441                 value_num= get_le16(pb);//we should use get_value() here but it does not work 2 is le16 here but le32 elsewhere
 442                 url_fskip(pb, value_len - 2);
 443
 444                 if(stream_num<128){
 445                     if     (!strcmp(name, "AspectRatioX")) dar[stream_num].num= value_num;
 446                     else if(!strcmp(name, "AspectRatioY")) dar[stream_num].den= value_num;
 447                 }
 448             }
 449         } else if (!memcmp(&g, &ext_stream_header, sizeof(GUID))) {
 450             int ext_len, payload_ext_ct, stream_ct;
 451             uint32_t ext_d, leak_rate, stream_num;
 452             int64_t pos_ex_st;
 453             pos_ex_st = url_ftell(pb);
 454
 455             get_le64(pb); // starttime
 456             get_le64(pb); // endtime
 457             leak_rate = get_le32(pb); // leak-datarate
 458             get_le32(pb); // bucket-datasize
 459             get_le32(pb); // init-bucket-fullness
 460             get_le32(pb); // alt-leak-datarate
 461             get_le32(pb); // alt-bucket-datasize
 462             get_le32(pb); // alt-init-bucket-fullness
 463             get_le32(pb); // max-object-size
 464             get_le32(pb); // flags (reliable,seekable,no_cleanpoints?,resend-live-cleanpoints, rest of bits reserved)
 465             stream_num = get_le16(pb); // stream-num
 466             get_le16(pb); // stream-language-id-index
 467             get_le64(pb); // avg frametime in 100ns units
 468             stream_ct = get_le16(pb); //stream-name-count
 469             payload_ext_ct = get_le16(pb); //payload-extension-system-count
 470
 471             if (stream_num < 128)
 472                 bitrate[stream_num] = leak_rate;
 473
 474             for (i=0; i<stream_ct; i++){
 475                 get_le16(pb);
 476                 ext_len = get_le16(pb);
 477                 url_fseek(pb, ext_len, SEEK_CUR);
 478             }
 479
 480             for (i=0; i<payload_ext_ct; i++){
 481                 get_guid(pb, &g);
 482                 ext_d=get_le16(pb);
 483                 ext_len=get_le32(pb);
 484                 url_fseek(pb, ext_len, SEEK_CUR);
 485             }
 486
 487             // there could be a optional stream properties object to follow
 488             // if so the next iteration will pick it up
 489         } else if (!memcmp(&g, &head1_guid, sizeof(GUID))) {
 490             int v1, v2;
 491             get_guid(pb, &g);
 492             v1 = get_le32(pb);
 493             v2 = get_le16(pb);
 494 #if 0
 495         } else if (!memcmp(&g, &codec_comment_header, sizeof(GUID))) {
 496             int len, v1, n, num;
 497             char str[256], *q;
 498             char tag[16];
 499
 500             get_guid(pb, &g);
 501             print_guid(&g);
 502
 503             n = get_le32(pb);
 504             for(i=0;i<n;i++) {
 505                 num = get_le16(pb); /* stream number */
 506                 get_str16(pb, str, sizeof(str));
 507                 get_str16(pb, str, sizeof(str));
 508                 len = get_le16(pb);
 509                 q = tag;
 510                 while (len > 0) {
 511                     v1 = get_byte(pb);
 512                     if ((q - tag) < sizeof(tag) - 1)
 513                         *q++ = v1;
 514                     len--;
 515                 }
 516                 *q = '\0';
 517             }
 518 #endif
 519         } else if (url_feof(pb)) {
 520             goto fail;
 521         } else {
 522             url_fseek(pb, gsize - 24, SEEK_CUR);
 523         }
 524     }
 525     get_guid(pb, &g);
 526     get_le64(pb);
 527     get_byte(pb);
 528     get_byte(pb);
 529     if (url_feof(pb))
 530         goto fail;
 531     asf->data_offset = url_ftell(pb);
 532     asf->packet_size_left = 0;
 533
 534
 535     for(i=0; i<128; i++){
 536         int stream_num= asf->asfid2avid[i];
 537         if(stream_num>=0){
 538             AVCodecContext *codec= s->streams[stream_num]->codec;
 539             if (!codec->bit_rate)
 540                 codec->bit_rate = bitrate[i];
 541             if (dar[i].num > 0 && dar[i].den > 0)
 542                 av_reduce(&codec->sample_aspect_ratio.num,
 543                           &codec->sample_aspect_ratio.den,
 544                           dar[i].num, dar[i].den, INT_MAX);
 545 //av_log(NULL, AV_LOG_ERROR, "dar %d:%d sar=%d:%d\n", dar[i].num, dar[i].den, codec->sample_aspect_ratio.num, codec->sample_aspect_ratio.den);
 546         }
 547     }
 548
 549 #ifdef CONFIG_MMSH_PROTOCOL
 550     /* Give info about ourselves to the mms protocol */
 551     if(is_mms(pb))
 552         ff_mms_set_stream_selection(url_fileno(pb), s);
 553 #endif
 554
 555     return 0;
 556
 557  fail:
 558      for(i=0;i<s->nb_streams;i++) {
 559         AVStream *st = s->streams[i];
 560         if (st) {
 561             av_free(st->priv_data);
 562             av_free(st->codec->extradata);
 563         }
 564         av_free(st);
 565     }
 566     return -1;
 567 }
 568
 569 #define DO_2BITS(bits, var, defval) \
 570     switch (bits & 3) \
 571     { \
 572     case 3: var = get_le32(pb); rsize += 4; break; \
 573     case 2: var = get_le16(pb); rsize += 2; break; \
 574     case 1: var = get_byte(pb); rsize++; break; \
 575     default: var = defval; break; \
 576     }
 577
 578 /**
 579  *
 580  * @return <0 in case of an error
 581  */
 582 static int asf_get_packet(AVFormatContext *s)
 583 {
 584     ASFContext *asf = s->priv_data;
 585     ByteIOContext *pb = s->pb;
 586     uint32_t packet_length, padsize;
 587     int rsize = 8;
 588     int c, d, e, off;
 589
 590     off= (url_ftell(s->pb) - s->data_offset) % asf->packet_size + 3;
 591
 592     c=d=e=-1;
 593     while(off-- > 0){
 594         c=d; d=e;
 595         e= get_byte(pb);
 596         if(c == 0x82 && !d && !e)
 597             break;
 598     }
 599
 600     if (c != 0x82) {
 601         if (!url_feof(pb))
 602             av_log(s, AV_LOG_ERROR, "ff asf bad header %x  at:%"PRId64"\n", c, url_ftell(pb));
 603     }
 604     if ((c & 0x8f) == 0x82) {
 605         if (d || e) {
 606             if (!url_feof(pb))
 607                 av_log(s, AV_LOG_ERROR, "ff asf bad non zero\n");
 608             return -1;
 609         }
 610         c= get_byte(pb);
 611         d= get_byte(pb);
 612         rsize+=3;
 613     }else{
 614         url_fseek(pb, -1, SEEK_CUR); //FIXME
 615     }
 616
 617     asf->packet_flags    = c;
 618     asf->packet_property = d;
 619
 620     DO_2BITS(asf->packet_flags >> 5, packet_length, asf->packet_size);
 621     DO_2BITS(asf->packet_flags >> 1, padsize, 0); // sequence ignored
 622     DO_2BITS(asf->packet_flags >> 3, padsize, 0); // padding length
 623
 624     //the following checks prevent overflows and infinite loops
 625     if(packet_length >= (1U<<29)){
 626         av_log(s, AV_LOG_ERROR, "invalid packet_length %d at:%"PRId64"\n", packet_length, url_ftell(pb));
 627         return -1;
 628     }
 629     if(padsize >= packet_length){
 630         av_log(s, AV_LOG_ERROR, "invalid padsize %d at:%"PRId64"\n", padsize, url_ftell(pb));
 631         return -1;
 632     }
 633
 634     asf->packet_timestamp = get_le32(pb);
 635     get_le16(pb); /* duration */
 636     // rsize has at least 11 bytes which have to be present
 637
 638     if (asf->packet_flags & 0x01) {
 639         asf->packet_segsizetype = get_byte(pb); rsize++;
 640         asf->packet_segments = asf->packet_segsizetype & 0x3f;
 641     } else {
 642         asf->packet_segments = 1;
 643         asf->packet_segsizetype = 0x80;
 644     }
 645     asf->packet_size_left = packet_length - padsize - rsize;
 646     if (packet_length < asf->hdr.min_pktsize)
 647         padsize += asf->hdr.min_pktsize - packet_length;
 648     asf->packet_padsize = padsize;
 649 #ifdef DEBUG
 650     printf("packet: size=%d padsize=%d  left=%d\n", asf->packet_size, asf->packet_padsize, asf->packet_size_left);
 651 #endif
 652     return 0;
 653 }
 654
 655 /**
 656  *
 657  * @return <0 if error
 658  */
 659 static int asf_read_frame_header(AVFormatContext *s){
 660     ASFContext *asf = s->priv_data;
 661     ByteIOContext *pb = s->pb;
 662     int rsize = 1;
 663     int num = get_byte(pb);
 664     int64_t ts0, ts1;
 665
 666     asf->packet_segments--;
 667     asf->packet_key_frame = num >> 7;
 668     asf->stream_index = asf->asfid2avid[num & 0x7f];
 669     // sequence should be ignored!
 670     DO_2BITS(asf->packet_property >> 4, asf->packet_seq, 0);
 671     DO_2BITS(asf->packet_property >> 2, asf->packet_frag_offset, 0);
 672     DO_2BITS(asf->packet_property, asf->packet_replic_size, 0);
 673 //printf("key:%d stream:%d seq:%d offset:%d replic_size:%d\n", asf->packet_key_frame, asf->stream_index, asf->packet_seq, //asf->packet_frag_offset, asf->packet_replic_size);
 674     if (asf->packet_replic_size >= 8) {
 675         asf->packet_obj_size = get_le32(pb);
 676         if(asf->packet_obj_size >= (1<<24) || asf->packet_obj_size <= 0){
 677             av_log(s, AV_LOG_ERROR, "packet_obj_size invalid\n");
 678             return -1;
 679         }
 680         asf->packet_frag_timestamp = get_le32(pb); // timestamp
 681         if(asf->packet_replic_size >= 8+38+4){
 682 //            for(i=0; i<asf->packet_replic_size-8; i++)
 683 //                av_log(s, AV_LOG_DEBUG, "%02X ",get_byte(pb));
 684 //            av_log(s, AV_LOG_DEBUG, "\n");
 685             url_fskip(pb, 10);
 686             ts0= get_le64(pb);
 687             ts1= get_le64(pb);
 688             url_fskip(pb, 12);
 689             get_le32(pb);
 690             url_fskip(pb, asf->packet_replic_size - 8 - 38 - 4);
 691             if(ts0!= -1) asf->packet_frag_timestamp= ts0/10000;
 692             else         asf->packet_frag_timestamp= AV_NOPTS_VALUE;
 693         }else
 694             url_fskip(pb, asf->packet_replic_size - 8);
 695         rsize += asf->packet_replic_size; // FIXME - check validity
 696     } else if (asf->packet_replic_size==1){
 697         // multipacket - frag_offset is begining timestamp
 698         asf->packet_time_start = asf->packet_frag_offset;
 699         asf->packet_frag_offset = 0;
 700         asf->packet_frag_timestamp = asf->packet_timestamp;
 701
 702         asf->packet_time_delta = get_byte(pb);
 703         rsize++;
 704     }else if(asf->packet_replic_size!=0){
 705         av_log(s, AV_LOG_ERROR, "unexpected packet_replic_size of %d\n", asf->packet_replic_size);
 706         return -1;
 707     }
 708     if (asf->packet_flags & 0x01) {
 709         DO_2BITS(asf->packet_segsizetype >> 6, asf->packet_frag_size, 0); // 0 is illegal
 710         if(asf->packet_frag_size > asf->packet_size_left - rsize){
 711             av_log(s, AV_LOG_ERROR, "packet_frag_size is invalid\n");
 712             return -1;
 713         }
 714         //printf("Fragsize %d\n", asf->packet_frag_size);
 715     } else {
 716         asf->packet_frag_size = asf->packet_size_left - rsize;
 717         //printf("Using rest  %d %d %d\n", asf->packet_frag_size, asf->packet_size_left, rsize);
 718     }
 719     if (asf->packet_replic_size == 1) {
 720         asf->packet_multi_size = asf->packet_frag_size;
 721         if (asf->packet_multi_size > asf->packet_size_left)
 722             return -1;
 723     }
 724     asf->packet_size_left -= rsize;
 725     //printf("___objsize____  %d   %d    rs:%d\n", asf->packet_obj_size, asf->packet_frag_offset, rsize);
 726
 727     return 0;
 728 }
 729
 730 static int asf_read_packet(AVFormatContext *s, AVPacket *pkt)
 731 {
 732     ASFContext *asf = s->priv_data;
 733     ASFStream *asf_st = 0;
 734     ByteIOContext *pb = s->pb;
 735     //static int pc = 0;
 736     for (;;) {
 737         if(url_feof(pb))
 738             return AVERROR(EIO);
 739         if (asf->packet_size_left < FRAME_HEADER_SIZE
 740             || asf->packet_segments < 1) {
 741             //asf->packet_size_left <= asf->packet_padsize) {
 742             int ret = asf->packet_size_left + asf->packet_padsize;
 743             //printf("PacketLeftSize:%d  Pad:%d Pos:%"PRId64"\n", asf->packet_size_left, asf->packet_padsize, url_ftell(pb));
 744             assert(ret>=0);
 745             /* fail safe */
 746             url_fskip(pb, ret);
 747
 748             asf->packet_pos= url_ftell(s->pb);
 749             if (asf->data_object_size != (uint64_t)-1 &&
 750                 (asf->packet_pos - asf->data_object_offset >= asf->data_object_size))
 751                 return AVERROR(EIO); /* Do not exceed the size of the data object */
 752             ret = asf_get_packet(s);
 753             //printf("READ ASF PACKET  %d   r:%d   c:%d\n", ret, asf->packet_size_left, pc++);
 754             if (ret < 0)
 755                 assert(asf->packet_size_left < FRAME_HEADER_SIZE || asf->packet_segments < 1);
 756             asf->packet_time_start = 0;
 757             continue;
 758         }
 759         if (asf->packet_time_start == 0) {
 760             if(asf_read_frame_header(s) < 0){
 761                 asf->packet_segments= 0;
 762                 continue;
 763             }
 764             if (asf->stream_index < 0
 765                 || s->streams[asf->stream_index]->discard >= AVDISCARD_ALL
 766                 || (!asf->packet_key_frame && s->streams[asf->stream_index]->discard >= AVDISCARD_NONKEY)
 767                 ) {
 768                 asf->packet_time_start = 0;
 769                 /* unhandled packet (should not happen) */
 770                 url_fskip(pb, asf->packet_frag_size);
 771                 asf->packet_size_left -= asf->packet_frag_size;
 772                 if(asf->stream_index < 0)
 773                     av_log(s, AV_LOG_ERROR, "ff asf skip %d (unknown stream)\n", asf->packet_frag_size);
 774                 continue;
 775             }
 776             asf->asf_st = s->streams[asf->stream_index]->priv_data;
 777         }
 778         asf_st = asf->asf_st;
 779
 780         if (asf->packet_replic_size == 1) {
 781             // frag_offset is here used as the begining timestamp
 782             asf->packet_frag_timestamp = asf->packet_time_start;
 783             asf->packet_time_start += asf->packet_time_delta;
 784             asf->packet_obj_size = asf->packet_frag_size = get_byte(pb);
 785             asf->packet_size_left--;
 786             asf->packet_multi_size--;
 787             if (asf->packet_multi_size < asf->packet_obj_size)
 788             {
 789                 asf->packet_time_start = 0;
 790                 url_fskip(pb, asf->packet_multi_size);
 791                 asf->packet_size_left -= asf->packet_multi_size;
 792                 continue;
 793             }
 794             asf->packet_multi_size -= asf->packet_obj_size;
 795             //printf("COMPRESS size  %d  %d  %d   ms:%d\n", asf->packet_obj_size, asf->packet_frag_timestamp, asf->packet_size_left, asf->packet_multi_size);
 796         }
 797         if(   /*asf->packet_frag_size == asf->packet_obj_size*/
 798               asf_st->frag_offset + asf->packet_frag_size <= asf_st->pkt.size
 799            && asf_st->frag_offset + asf->packet_frag_size > asf->packet_obj_size){
 800             av_log(s, AV_LOG_INFO, "ignoring invalid packet_obj_size (%d %d %d %d)\n",
 801                 asf_st->frag_offset, asf->packet_frag_size,
 802                 asf->packet_obj_size, asf_st->pkt.size);
 803             asf->packet_obj_size= asf_st->pkt.size;
 804         }
 805
 806         if (   asf_st->pkt.size != asf->packet_obj_size
 807             || asf_st->frag_offset + asf->packet_frag_size > asf_st->pkt.size) { //FIXME is this condition sufficient?
 808             if(asf_st->pkt.data){
 809                 av_log(s, AV_LOG_INFO, "freeing incomplete packet size %d, new %d\n", asf_st->pkt.size, asf->packet_obj_size);
 810                 asf_st->frag_offset = 0;
 811                 av_free_packet(&asf_st->pkt);
 812             }
 813             /* new packet */
 814             av_new_packet(&asf_st->pkt, asf->packet_obj_size);
 815             asf_st->seq = asf->packet_seq;
 816             asf_st->pkt.pts = asf->packet_frag_timestamp;
 817             asf_st->pkt.stream_index = asf->stream_index;
 818             asf_st->pkt.pos =
 819             asf_st->packet_pos= asf->packet_pos;
 820 //printf("new packet: stream:%d key:%d packet_key:%d audio:%d size:%d\n",
 821 //asf->stream_index, asf->packet_key_frame, asf_st->pkt.flags & PKT_FLAG_KEY,
 822 //s->streams[asf->stream_index]->codec->codec_type == CODEC_TYPE_AUDIO, asf->packet_obj_size);
 823             if (s->streams[asf->stream_index]->codec->codec_type == CODEC_TYPE_AUDIO)
 824                 asf->packet_key_frame = 1;
 825             if (asf->packet_key_frame)
 826                 asf_st->pkt.flags |= PKT_FLAG_KEY;
 827         }
 828
 829         /* read data */
 830         //printf("READ PACKET s:%d  os:%d  o:%d,%d  l:%d   DATA:%p\n",
 831         //       asf->packet_size, asf_st->pkt.size, asf->packet_frag_offset,
 832         //       asf_st->frag_offset, asf->packet_frag_size, asf_st->pkt.data);
 833         asf->packet_size_left -= asf->packet_frag_size;
 834         if (asf->packet_size_left < 0)
 835             continue;
 836
 837         if(   asf->packet_frag_offset >= asf_st->pkt.size
 838            || asf->packet_frag_size > asf_st->pkt.size - asf->packet_frag_offset){
 839             av_log(s, AV_LOG_ERROR, "packet fragment position invalid %u,%u not in %u\n",
 840                 asf->packet_frag_offset, asf->packet_frag_size, asf_st->pkt.size);
 841             continue;
 842         }
 843
 844         get_buffer(pb, asf_st->pkt.data + asf->packet_frag_offset,
 845                    asf->packet_frag_size);
 846         if (s->key && s->keylen == 20)
 847             ff_asfcrypt_dec(s->key, asf_st->pkt.data + asf->packet_frag_offset,
 848                             asf->packet_frag_size);
 849         asf_st->frag_offset += asf->packet_frag_size;
 850         /* test if whole packet is read */
 851         if (asf_st->frag_offset == asf_st->pkt.size) {
 852             //workaround for macroshit radio DVR-MS files
 853             if(   s->streams[asf->stream_index]->codec->codec_id == CODEC_ID_MPEG2VIDEO
 854                && asf_st->pkt.size > 100){
 855                 int i;
 856                 for(i=0; i<asf_st->pkt.size && !asf_st->pkt.data[i]; i++);
 857                 if(i == asf_st->pkt.size){
 858                     av_log(s, AV_LOG_DEBUG, "discarding ms fart\n");
 859                     asf_st->frag_offset = 0;
 860                     av_free_packet(&asf_st->pkt);
 861                     continue;
 862                 }
 863             }
 864
 865             /* return packet */
 866             if (asf_st->ds_span > 1) {
 867               if(asf_st->pkt.size != asf_st->ds_packet_size * asf_st->ds_span){
 868                     av_log(s, AV_LOG_ERROR, "pkt.size != ds_packet_size * ds_span (%d %d %d)\n", asf_st->pkt.size, asf_st->ds_packet_size, asf_st->ds_span);
 869               }else{
 870                 /* packet descrambling */
 871                 uint8_t *newdata = av_malloc(asf_st->pkt.size);
 872                 if (newdata) {
 873                     int offset = 0;
 874                     while (offset < asf_st->pkt.size) {
 875                         int off = offset / asf_st->ds_chunk_size;
 876                         int row = off / asf_st->ds_span;
 877                         int col = off % asf_st->ds_span;
 878                         int idx = row + col * asf_st->ds_packet_size / asf_st->ds_chunk_size;
 879                         //printf("off:%d  row:%d  col:%d  idx:%d\n", off, row, col, idx);
 880
 881                         assert(offset + asf_st->ds_chunk_size <= asf_st->pkt.size);
 882                         assert(idx+1 <= asf_st->pkt.size / asf_st->ds_chunk_size);
 883                         memcpy(newdata + offset,
 884                                asf_st->pkt.data + idx * asf_st->ds_chunk_size,
 885                                asf_st->ds_chunk_size);
 886                         offset += asf_st->ds_chunk_size;
 887                     }
 888                     av_free(asf_st->pkt.data);
 889                     asf_st->pkt.data = newdata;
 890                 }
 891               }
 892             }
 893             asf_st->frag_offset = 0;
 894             *pkt= asf_st->pkt;
 895             //printf("packet %d %d\n", asf_st->pkt.size, asf->packet_frag_size);
 896             asf_st->pkt.size = 0;
 897             asf_st->pkt.data = 0;
 898             break; // packet completed
 899         }
 900     }
 901     return 0;
 902 }
 903
 904 // Added to support seeking after packets have been read
 905 // If information is not reset, read_packet fails due to
 906 // leftover information from previous reads
 907 static void asf_reset_header(AVFormatContext *s)
 908 {
 909     ASFContext *asf = s->priv_data;
 910     ASFStream *asf_st;
 911     int i;
 912
 913     asf->packet_nb_frames = 0;
 914     asf->packet_size_left = 0;
 915     asf->packet_segments = 0;
 916     asf->packet_flags = 0;
 917     asf->packet_property = 0;
 918     asf->packet_timestamp = 0;
 919     asf->packet_segsizetype = 0;
 920     asf->packet_segments = 0;
 921     asf->packet_seq = 0;
 922     asf->packet_replic_size = 0;
 923     asf->packet_key_frame = 0;
 924     asf->packet_padsize = 0;
 925     asf->packet_frag_offset = 0;
 926     asf->packet_frag_size = 0;
 927     asf->packet_frag_timestamp = 0;
 928     asf->packet_multi_size = 0;
 929     asf->packet_obj_size = 0;
 930     asf->packet_time_delta = 0;
 931     asf->packet_time_start = 0;
 932
 933     for(i=0; i<s->nb_streams; i++){
 934         asf_st= s->streams[i]->priv_data;
 935         av_free_packet(&asf_st->pkt);
 936         asf_st->frag_offset=0;
 937         asf_st->seq=0;
 938     }
 939     asf->asf_st= NULL;
 940 }
 941
 942 static int asf_read_close(AVFormatContext *s)
 943 {
 944     int i;
 945
 946     asf_reset_header(s);
 947     for(i=0;i<s->nb_streams;i++) {
 948         AVStream *st = s->streams[i];
 949         av_free(st->priv_data);
 950         av_free(st->codec->palctrl);
 951     }
 952     return 0;
 953 }
 954
 955 static int64_t asf_read_pts(AVFormatContext *s, int stream_index, int64_t *ppos, int64_t pos_limit)
 956 {
 957     ASFContext *asf = s->priv_data;
 958     AVPacket pkt1, *pkt = &pkt1;
 959     ASFStream *asf_st;
 960     int64_t pts;
 961     int64_t pos= *ppos;
 962     int i;
 963     int64_t start_pos[s->nb_streams];
 964
 965     for(i=0; i<s->nb_streams; i++){
 966         start_pos[i]= pos;
 967     }
 968
 969     pos= (pos+asf->packet_size-1-s->data_offset)/asf->packet_size*asf->packet_size+ s->data_offset;
 970     *ppos= pos;
 971     url_fseek(s->pb, pos, SEEK_SET);
 972
 973 //printf("asf_read_pts\n");
 974     asf_reset_header(s);
 975     for(;;){
 976         if (av_read_frame(s, pkt) < 0){
 977             av_log(s, AV_LOG_INFO, "asf_read_pts failed\n");
 978             return AV_NOPTS_VALUE;
 979         }
 980
 981         pts= pkt->pts;
 982
 983         av_free_packet(pkt);
 984         if(pkt->flags&PKT_FLAG_KEY){
 985             i= pkt->stream_index;
 986
 987             asf_st= s->streams[i]->priv_data;
 988
 989 //            assert((asf_st->packet_pos - s->data_offset) % asf->packet_size == 0);
 990             pos= asf_st->packet_pos;
 991
 992             av_add_index_entry(s->streams[i], pos, pts, pkt->size, pos - start_pos[i] + 1, AVINDEX_KEYFRAME);
 993             start_pos[i]= asf_st->packet_pos + 1;
 994
 995             if(pkt->stream_index == stream_index)
 996                break;
 997         }
 998     }
 999
1000     *ppos= pos;
1001 //printf("found keyframe at %"PRId64" stream %d stamp:%"PRId64"\n", *ppos, stream_index, pts);
1002
1003     return pts;
1004 }
1005
1006 static void asf_build_simple_index(AVFormatContext *s, int stream_index)
1007 {
1008     GUID g;
1009     ASFContext *asf = s->priv_data;
1010     int64_t gsize, itime;
1011     int64_t pos, current_pos, index_pts;
1012     int i;
1013     int pct,ict;
1014
1015     current_pos = url_ftell(s->pb);
1016
1017     url_fseek(s->pb, asf->data_object_offset + asf->data_object_size, SEEK_SET);
1018     get_guid(s->pb, &g);
1019     if (!memcmp(&g, &index_guid, sizeof(GUID))) {
1020         gsize = get_le64(s->pb);
1021         get_guid(s->pb, &g);
1022         itime=get_le64(s->pb);
1023         pct=get_le32(s->pb);
1024         ict=get_le32(s->pb);
1025         av_log(NULL, AV_LOG_DEBUG, "itime:0x%"PRIx64", pct:%d, ict:%d\n",itime,pct,ict);
1026
1027         for (i=0;i<ict;i++){
1028             int pktnum=get_le32(s->pb);
1029             int pktct =get_le16(s->pb);
1030             av_log(NULL, AV_LOG_DEBUG, "pktnum:%d, pktct:%d\n", pktnum, pktct);
1031
1032             pos=s->data_offset + asf->packet_size*(int64_t)pktnum;
1033             index_pts=av_rescale(itime, i, 10000);
1034
1035             av_add_index_entry(s->streams[stream_index], pos, index_pts, asf->packet_size, 0, AVINDEX_KEYFRAME);
1036         }
1037         asf->index_read= 1;
1038     }
1039     url_fseek(s->pb, current_pos, SEEK_SET);
1040 }
1041
1042 static int asf_read_seek(AVFormatContext *s, int stream_index, int64_t pts, int flags)
1043 {
1044     ASFContext *asf = s->priv_data;
1045     AVStream *st = s->streams[stream_index];
1046     int64_t pos;
1047     int index;
1048
1049     if (asf->packet_size <= 0)
1050         return -1;
1051
1052     if (!asf->index_read)
1053         asf_build_simple_index(s, stream_index);
1054
1055     if(!(asf->index_read && st->index_entries)){
1056         if(av_seek_frame_binary(s, stream_index, pts, flags)<0)
1057             return -1;
1058     }else{
1059         index= av_index_search_timestamp(st, pts, flags);
1060         if(index<0)
1061             return -1;
1062
1063         /* find the position */
1064         pos = st->index_entries[index].pos;
1065         pts = st->index_entries[index].timestamp;
1066
1067     // various attempts to find key frame have failed so far
1068     //    asf_reset_header(s);
1069     //    url_fseek(s->pb, pos, SEEK_SET);
1070     //    key_pos = pos;
1071     //     for(i=0;i<16;i++){
1072     //         pos = url_ftell(s->pb);
1073     //         if (av_read_frame(s, &pkt) < 0){
1074     //             av_log(s, AV_LOG_INFO, "seek failed\n");
1075     //             return -1;
1076     //         }
1077     //         asf_st = s->streams[stream_index]->priv_data;
1078     //         pos += st->parser->frame_offset;
1079     //
1080     //         if (pkt.size > b) {
1081     //             b = pkt.size;
1082     //             key_pos = pos;
1083     //         }
1084     //
1085     //         av_free_packet(&pkt);
1086     //     }
1087
1088         /* do the seek */
1089         av_log(NULL, AV_LOG_DEBUG, "SEEKTO: %"PRId64"\n", pos);
1090         url_fseek(s->pb, pos, SEEK_SET);
1091     }
1092     asf_reset_header(s);
1093     return 0;
1094 }
1095
1096 AVInputFormat asf_demuxer = {
1097     "asf",
1098     "asf format",
1099     sizeof(ASFContext),
1100     asf_probe,
1101     asf_read_header,
1102     asf_read_packet,
1103     asf_read_close,
1104     asf_read_seek,
1105     asf_read_pts,
1106 };