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

   1 /*
   2  * Windows Television (WTV) demuxer
   3  * Copyright (c) 2010 Peter Ross <pross@xvid.org>
   4  *
   5  * This file is part of FFmpeg.
   6  *
   7  * FFmpeg is free software; you can redistribute it and/or
   8  * modify it under the terms of the GNU Lesser General Public
   9  * License as published by the Free Software Foundation; either
  10  * version 2.1 of the License, or (at your option) any later version.
  11  *
  12  * FFmpeg is distributed in the hope that it will be useful,
  13  * but WITHOUT ANY WARRANTY; without even the implied warranty of
  14  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
  15  * Lesser General Public License for more details.
  16  *
  17  * You should have received a copy of the GNU Lesser General Public
  18  * License along with FFmpeg; if not, write to the Free Software
  19  * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA
  20  */
  21
  22 /**
  23  * @file
  24  * Windows Television (WTV) demuxer
  25  * @author Peter Ross <pross@xvid.org>
  26  */
  27
  28 #include "libavutil/intreadwrite.h"
  29 #include "avformat.h"
  30 #include "riff.h"
  31 #include "asf.h"
  32 #include "mpegts.h"
  33
  34 /* Macros for formating GUIDs */
  35 #define PRI_GUID \
  36     "%02x%02x%02x%02x%02x%02x%02x%02x%02x%02x%02x%02x%02x%02x%02x%02x"
  37 #define ARG_GUID(g) \
  38     g[0],g[1],g[2],g[3],g[4],g[5],g[6],g[7],g[8],g[9],g[10],g[11],g[12],g[13],g[14],g[15]
  39
  40 typedef struct {
  41     int seen_data;
  42 } WtvStream;
  43
  44 typedef struct WtvContext {
  45     uint64_t pts;
  46 } WtvContext;
  47
  48 static int is_zero(uint8_t *v, int n)
  49 {
  50    int i;
  51    for (i = 0; i < n; i++)
  52       if (v[i]) return 0;
  53    return 1;
  54 }
  55
  56 typedef struct {
  57     enum CodecID id;
  58     ff_asf_guid guid;
  59 } AVCodecGuid;
  60
  61 static enum CodecID ff_codec_guid_get_id(const AVCodecGuid *guids, ff_asf_guid guid)
  62 {
  63     int i;
  64     for (i = 0; guids[i].id != CODEC_ID_NONE; i++) {
  65         if (!ff_guidcmp(guids[i].guid, guid))
  66             return guids[i].id;
  67     }
  68     return CODEC_ID_NONE;
  69 }
  70
  71 /* WTV GUIDs */
  72 static const ff_asf_guid wtv_guid =
  73     {0xB7,0xD8,0x00,0x20,0x37,0x49,0xDA,0x11,0xA6,0x4E,0x00,0x07,0xE9,0x5E,0xAD,0x8D};
  74 static const ff_asf_guid meta_guid =
  75     {0x5A,0xFE,0xD7,0x6D,0xC8,0x1D,0x8F,0x4A,0x99,0x22,0xFA,0xB1,0x1C,0x38,0x14,0x53};
  76 static const ff_asf_guid timestamp_guid =
  77     {0x5B,0x05,0xE6,0x1B,0x97,0xA9,0x49,0x43,0x88,0x17,0x1A,0x65,0x5A,0x29,0x8A,0x97};
  78 static const ff_asf_guid data_guid =
  79     {0x95,0xC3,0xD2,0xC2,0x7E,0x9A,0xDA,0x11,0x8B,0xF7,0x00,0x07,0xE9,0x5E,0xAD,0x8D};
  80 static const ff_asf_guid stream_guid =
  81     {0xED,0xA4,0x13,0x23,0x2D,0xBF,0x4F,0x45,0xAD,0x8A,0xD9,0x5B,0xA7,0xF9,0x1F,0xEE};
  82 static const ff_asf_guid stream2_guid =
  83     {0xA2,0xC3,0xD2,0xC2,0x7E,0x9A,0xDA,0x11,0x8B,0xF7,0x00,0x07,0xE9,0x5E,0xAD,0x8D};
  84 static const ff_asf_guid EVENTID_SubtitleSpanningEvent =
  85     {0x48,0xC0,0xCE,0x5D,0xB9,0xD0,0x63,0x41,0x87,0x2C,0x4F,0x32,0x22,0x3B,0xE8,0x8A};
  86 static const ff_asf_guid EVENTID_LanguageSpanningEvent =
  87     {0x6D,0x66,0x92,0xE2,0x02,0x9C,0x8D,0x44,0xAA,0x8D,0x78,0x1A,0x93,0xFD,0xC3,0x95};
  88 static const ff_asf_guid EVENTID_AudioDescriptorSpanningEvent =
  89     {0x1C,0xD4,0x7B,0x10,0xDA,0xA6,0x91,0x46,0x83,0x69,0x11,0xB2,0xCD,0xAA,0x28,0x8E};
  90 static const ff_asf_guid EVENTID_CtxADescriptorSpanningEvent =
  91     {0xE6,0xA2,0xB4,0x3A,0x47,0x42,0x34,0x4B,0x89,0x6C,0x30,0xAF,0xA5,0xD2,0x1C,0x24};
  92 static const ff_asf_guid EVENTID_CSDescriptorSpanningEvent =
  93     {0xD9,0x79,0xE7,0xEf,0xF0,0x97,0x86,0x47,0x80,0x0D,0x95,0xCF,0x50,0x5D,0xDC,0x66};
  94 static const ff_asf_guid EVENTID_DVBScramblingControlSpanningEvent =
  95     {0xC4,0xE1,0xD4,0x4B,0xA1,0x90,0x09,0x41,0x82,0x36,0x27,0xF0,0x0E,0x7D,0xCC,0x5B};
  96 static const ff_asf_guid EVENTID_StreamIDSpanningEvent =
  97     {0x68,0xAB,0xF1,0xCA,0x53,0xE1,0x41,0x4D,0xA6,0xB3,0xA7,0xC9,0x98,0xDB,0x75,0xEE};
  98 static const ff_asf_guid EVENTID_TeletextSpanningEvent =
  99     {0x50,0xD9,0x99,0x95,0x33,0x5F,0x17,0x46,0xAF,0x7C,0x1E,0x54,0xB5,0x10,0xDA,0xA3};
 100
 101 /* Windows media GUIDs */
 102
 103 #define MEDIASUBTYPE_BASE_GUID \
 104     0x00,0x00,0x10,0x00,0x80,0x00,0x00,0xAA,0x00,0x38,0x9B,0x71
 105
 106 /* Media types */
 107 static const ff_asf_guid mediatype_audio =
 108     {'a','u','d','s',MEDIASUBTYPE_BASE_GUID};
 109 static const ff_asf_guid mediatype_video =
 110     {'v','i','d','s',MEDIASUBTYPE_BASE_GUID};
 111 static const ff_asf_guid mediasubtype_mpeg1payload =
 112     {0x81,0xEB,0x36,0xE4,0x4F,0x52,0xCE,0x11,0x9F,0x53,0x00,0x20,0xAF,0x0B,0xA7,0x70};
 113 static const ff_asf_guid mediatype_mpeg2_sections =
 114     {0x6C,0x17,0x5F,0x45,0x06,0x4B,0xCE,0x47,0x9A,0xEF,0x8C,0xAE,0xF7,0x3D,0xF7,0xB5};
 115 static const ff_asf_guid mediatype_mpeg2_pes =
 116     {0x20,0x80,0x6D,0xE0,0x46,0xDB,0xCF,0x11,0xB4,0xD1,0x00,0x80,0x5F,0x6C,0xBB,0xEA};
 117 static const ff_asf_guid mediatype_mstvcaption =
 118     {0x89,0x8A,0x8B,0xB8,0x49,0xB0,0x80,0x4C,0xAD,0xCF,0x58,0x98,0x98,0x5E,0x22,0xC1};
 119
 120 /* Media subtypes */
 121 static const ff_asf_guid mediasubtype_cpfilters_processed =
 122     {0x28,0xBD,0xAD,0x46,0xD0,0x6F,0x96,0x47,0x93,0xB2,0x15,0x5C,0x51,0xDC,0x04,0x8D};
 123 static const ff_asf_guid mediasubtype_dvb_subtitle =
 124     {0xC3,0xCB,0xFF,0x34,0xB3,0xD5,0x71,0x41,0x90,0x02,0xD4,0xC6,0x03,0x01,0x69,0x7F};
 125 static const ff_asf_guid mediasubtype_teletext =
 126     {0xE3,0x76,0x2A,0xF7,0x0A,0xEB,0xD0,0x11,0xAC,0xE4,0x00,0x00,0xC0,0xCC,0x16,0xBA};
 127 static const ff_asf_guid mediasubtype_dtvccdata =
 128     {0xAA,0xDD,0x2A,0xF5,0xF0,0x36,0xF5,0x43,0x95,0xEA,0x6D,0x86,0x64,0x84,0x26,0x2A};
 129 static const ff_asf_guid mediasubtype_mpeg2_sections =
 130     {0x79,0x85,0x9F,0x4A,0xF8,0x6B,0x92,0x43,0x8A,0x6D,0xD2,0xDD,0x09,0xFA,0x78,0x61};
 131
 132 /* Formats */
 133 static const ff_asf_guid format_cpfilters_processed =
 134     {0x6F,0xB3,0x39,0x67,0x5F,0x1D,0xC2,0x4A,0x81,0x92,0x28,0xBB,0x0E,0x73,0xD1,0x6A};
 135 static const ff_asf_guid format_waveformatex =
 136     {0x81,0x9F,0x58,0x05,0x56,0xC3,0xCE,0x11,0xBF,0x01,0x00,0xAA,0x00,0x55,0x59,0x5A};
 137 static const ff_asf_guid format_videoinfo2 =
 138     {0xA0,0x76,0x2A,0xF7,0x0A,0xEB,0xD0,0x11,0xAC,0xE4,0x00,0x00,0xC0,0xCC,0x16,0xBA};
 139 static const ff_asf_guid format_mpeg2_video =
 140     {0xE3,0x80,0x6D,0xE0,0x46,0xDB,0xCF,0x11,0xB4,0xD1,0x00,0x80,0x5F,0x6C,0xBB,0xEA};
 141 static const ff_asf_guid format_none =
 142     {0xD6,0x17,0x64,0x0F,0x18,0xC3,0xD0,0x11,0xA4,0x3F,0x00,0xA0,0xC9,0x22,0x31,0x96};
 143
 144 static const AVCodecGuid video_guids[] = {
 145     {CODEC_ID_MPEG2VIDEO, {0x26,0x80,0x6D,0xE0,0x46,0xDB,0xCF,0x11,0xB4,0xD1,0x00,0x80,0x5F,0x6C,0xBB,0xEA}},
 146     {CODEC_ID_NONE}
 147 };
 148
 149 static const AVCodecGuid audio_guids[] = {
 150     {CODEC_ID_AC3,        {0x2C,0x80,0x6D,0xE0,0x46,0xDB,0xCF,0x11,0xB4,0xD1,0x00,0x80,0x5F,0x6C,0xBB,0xEA}},
 151     {CODEC_ID_EAC3,       {0xAF,0x87,0xFB,0xA7,0x02,0x2D,0xFB,0x42,0xA4,0xD4,0x05,0xCD,0x93,0x84,0x3B,0xDD}},
 152     {CODEC_ID_MP2,        {0x2B,0x80,0x6D,0xE0,0x46,0xDB,0xCF,0x11,0xB4,0xD1,0x00,0x80,0x5F,0x6C,0xBB,0xEA}},
 153     {CODEC_ID_NONE}
 154 };
 155
 156 static int read_probe(AVProbeData *p)
 157 {
 158     return ff_guidcmp(p->buf, wtv_guid) ? 0 : AVPROBE_SCORE_MAX;
 159 }
 160
 161 /**
 162  * parse VIDEOINFOHEADER2 structure
 163  * @return bytes consumed
 164  */
 165 static int parse_videoinfoheader2(AVFormatContext *s, AVStream *st)
 166 {
 167     ByteIOContext *pb = s->pb;
 168
 169     url_fskip(pb, 72);  // picture aspect ratio is unreliable
 170     ff_get_bmp_header(pb, st);
 171
 172     return 72 + 40;
 173 }
 174
 175 /**
 176  * Parse MPEG1WAVEFORMATEX extradata structure
 177  */
 178 static void parse_mpeg1waveformatex(AVStream *st)
 179 {
 180     /* fwHeadLayer */
 181     switch (AV_RL16(st->codec->extradata)) {
 182     case 0x0001 : st->codec->codec_id = CODEC_ID_MP1; break;
 183     case 0x0002 : st->codec->codec_id = CODEC_ID_MP2; break;
 184     case 0x0004 : st->codec->codec_id = CODEC_ID_MP3; break;
 185     }
 186
 187     st->codec->bit_rate = AV_RL32(st->codec->extradata + 2); /* dwHeadBitrate */
 188
 189     /* dwHeadMode */
 190     switch (AV_RL16(st->codec->extradata + 6)) {
 191     case 1 : case 2 : case 4 : st->codec->channels = 2; break;
 192     case 8 :                   st->codec->channels = 1; break;
 193     }
 194 }
 195
 196 /**
 197  * Initialise stream
 198  * @param st Stream to initialise, or NULL to create and initialise new stream
 199  * @return NULL on error
 200  */
 201 static AVStream * new_stream(AVFormatContext *s, AVStream *st, int sid, int codec_type)
 202 {
 203     if (st) {
 204         if (st->codec->extradata) {
 205             av_freep(&st->codec->extradata);
 206             st->codec->extradata_size = 0;
 207         }
 208     } else {
 209         WtvStream *wst = av_mallocz(sizeof(WtvStream));
 210         if (!wst)
 211             return NULL;
 212         st = av_new_stream(s, sid);
 213         if (!st)
 214             return NULL;
 215         st->priv_data = wst;
 216     }
 217     st->codec->codec_type = codec_type;
 218     st->need_parsing      = AVSTREAM_PARSE_FULL;
 219     av_set_pts_info(st, 64, 1, 10000000);
 220     return st;
 221 }
 222
 223 /**
 224  * parse Media Type structure and populate stream
 225  * @param st         Stream, or NULL to create new stream
 226  * @param mediatype  Mediatype GUID
 227  * @param subtype    Subtype GUID
 228  * @param formattype Format GUID
 229  * @param size       Size of format buffer
 230  * @return NULL on error
 231  */
 232 static AVStream * parse_media_type(AVFormatContext *s, AVStream *st, int sid,
 233                                    ff_asf_guid mediatype, ff_asf_guid subtype,
 234                                    ff_asf_guid formattype, int size)
 235 {
 236     ByteIOContext *pb = s->pb;
 237     if (!ff_guidcmp(subtype, mediasubtype_cpfilters_processed) &&
 238         !ff_guidcmp(formattype, format_cpfilters_processed)) {
 239         ff_asf_guid actual_subtype;
 240         ff_asf_guid actual_formattype;
 241
 242         if (size < 32) {
 243             av_log(s, AV_LOG_WARNING, "format buffer size underflow\n");
 244             url_fskip(pb, size);
 245             return NULL;
 246         }
 247
 248         url_fskip(pb, size - 32);
 249         ff_get_guid(pb, &actual_subtype);
 250         ff_get_guid(pb, &actual_formattype);
 251         url_fseek(pb, -size, SEEK_CUR);
 252
 253         st = parse_media_type(s, st, sid, mediatype, actual_subtype, actual_formattype, size - 32);
 254         url_fskip(pb, 32);
 255         return st;
 256     } else if (!ff_guidcmp(mediatype, mediatype_audio)) {
 257         st = new_stream(s, st, sid, AVMEDIA_TYPE_AUDIO);
 258         if (!st)
 259             return NULL;
 260         if (!ff_guidcmp(formattype, format_waveformatex)) {
 261             ff_get_wav_header(pb, st->codec, size);
 262         } else {
 263             if (ff_guidcmp(formattype, format_none))
 264                 av_log(s, AV_LOG_WARNING, "unknown formattype:"PRI_GUID"\n", ARG_GUID(formattype));
 265             url_fskip(pb, size);
 266         }
 267
 268         if (!memcmp(subtype + 4, (const uint8_t[]){MEDIASUBTYPE_BASE_GUID}, 12)) {
 269             st->codec->codec_id = ff_wav_codec_get_id(AV_RL32(subtype), st->codec->bits_per_coded_sample);
 270         } else if (!ff_guidcmp(subtype, mediasubtype_mpeg1payload)) {
 271             if (st->codec->extradata && st->codec->extradata_size >= 22)
 272                 parse_mpeg1waveformatex(st);
 273             else
 274                 av_log(s, AV_LOG_WARNING, "MPEG1WAVEFORMATEX underflow\n");
 275         } else {
 276             st->codec->codec_id = ff_codec_guid_get_id(audio_guids, subtype);
 277             if (st->codec->codec_id == CODEC_ID_NONE)
 278                 av_log(s, AV_LOG_WARNING, "unknown subtype:"PRI_GUID"\n", ARG_GUID(subtype));
 279         }
 280         return st;
 281     } else if (!ff_guidcmp(mediatype, mediatype_video)) {
 282         st = new_stream(s, st, sid, AVMEDIA_TYPE_VIDEO);
 283         if (!st)
 284             return NULL;
 285         if (!ff_guidcmp(formattype, format_videoinfo2)) {
 286             int consumed = parse_videoinfoheader2(s, st);
 287             url_fskip(pb, FFMAX(size - consumed, 0));
 288         } else if (!ff_guidcmp(formattype, format_mpeg2_video)) {
 289             int consumed = parse_videoinfoheader2(s, st);
 290             url_fskip(pb, FFMAX(size - consumed, 0));
 291         } else {
 292             if (ff_guidcmp(formattype, format_none))
 293                 av_log(s, AV_LOG_WARNING, "unknown formattype:"PRI_GUID"\n", ARG_GUID(formattype));
 294             url_fskip(pb, size);
 295         }
 296
 297         if (!memcmp(subtype + 4, (const uint8_t[]){MEDIASUBTYPE_BASE_GUID}, 12)) {
 298             st->codec->codec_id = ff_codec_get_id(ff_codec_bmp_tags, AV_RL32(subtype));
 299         } else {
 300             st->codec->codec_id = ff_codec_guid_get_id(video_guids, subtype);
 301         }
 302         if (st->codec->codec_id == CODEC_ID_NONE)
 303             av_log(s, AV_LOG_WARNING, "unknown subtype:"PRI_GUID"\n", ARG_GUID(subtype));
 304         return st;
 305     } else if (!ff_guidcmp(mediatype, mediatype_mpeg2_pes) &&
 306                !ff_guidcmp(subtype, mediasubtype_dvb_subtitle)) {
 307         st = new_stream(s, st, sid, AVMEDIA_TYPE_SUBTITLE);
 308         if (!st)
 309             return NULL;
 310         if (ff_guidcmp(formattype, format_none))
 311             av_log(s, AV_LOG_WARNING, "unknown formattype:"PRI_GUID"\n", ARG_GUID(formattype));
 312         url_fskip(pb, size);
 313         st->codec->codec_id = CODEC_ID_DVB_SUBTITLE;
 314         return st;
 315     } else if (!ff_guidcmp(mediatype, mediatype_mstvcaption) &&
 316                (!ff_guidcmp(subtype, mediasubtype_teletext) || !ff_guidcmp(subtype, mediasubtype_dtvccdata))) {
 317         st = new_stream(s, st, sid, AVMEDIA_TYPE_SUBTITLE);
 318         if (!st)
 319             return NULL;
 320         if (ff_guidcmp(formattype, format_none))
 321             av_log(s, AV_LOG_WARNING, "unknown formattype:"PRI_GUID"\n", ARG_GUID(formattype));
 322         url_fskip(pb, size);
 323         st->codec->codec_id   = CODEC_ID_DVB_TELETEXT;
 324         return st;
 325     } else if (!ff_guidcmp(mediatype, mediatype_mpeg2_sections) &&
 326                !ff_guidcmp(subtype, mediasubtype_mpeg2_sections)) {
 327         if (ff_guidcmp(formattype, format_none))
 328             av_log(s, AV_LOG_WARNING, "unknown formattype:"PRI_GUID"\n", ARG_GUID(formattype));
 329         url_fskip(pb, size);
 330         return NULL;
 331     }
 332
 333     av_log(s, AV_LOG_WARNING, "unknown media type, mediatype:"PRI_GUID
 334                               ", subtype:"PRI_GUID", formattype:"PRI_GUID"\n",
 335                               ARG_GUID(mediatype), ARG_GUID(subtype), ARG_GUID(formattype));
 336     url_fskip(pb, size);
 337     return NULL;
 338 }
 339
 340 enum {
 341     SEEK_TO_DATA = 0,
 342     SEEK_TO_BYTE,
 343     SEEK_TO_PTS,
 344 };
 345
 346 /**
 347  * Parse WTV chunks
 348  * @param mode SEEK_TO_DATA, SEEK_TO_BYTE, SEEK_TO_PTS
 349  * @param seekts either byte position or timestamp
 350  * @param[out] len Length of data chunk
 351  * @return stream index of data chunk, or <0 on error
 352  */
 353 static int parse_chunks(AVFormatContext *s, int mode, int64_t seekts, int *len_ptr)
 354 {
 355     WtvContext *wtv = s->priv_data;
 356     ByteIOContext *pb = s->pb;
 357     while (!url_feof(pb)) {
 358         ff_asf_guid g;
 359         int len, sid, consumed;
 360
 361         if (mode == SEEK_TO_BYTE && url_ftell(pb) >= seekts)
 362             return 0;
 363
 364         ff_get_guid(pb, &g);
 365         if (is_zero(g, sizeof(ff_asf_guid)))
 366             return AVERROR_EOF;
 367
 368         len = get_le32(pb);
 369         if (len < 32)
 370             break;
 371         sid = get_le32(pb) & 0x7FFF;
 372         url_fskip(pb, 8);
 373         consumed = 32;
 374
 375         if (!ff_guidcmp(g, stream_guid)) {
 376             if (ff_find_stream_index(s, sid) < 0) {
 377                 ff_asf_guid mediatype, subtype, formattype;
 378                 int size;
 379                 consumed += 20;
 380                 url_fskip(pb, 16);
 381                 if (get_le32(pb)) {
 382                     url_fskip(pb, 8);
 383                     ff_get_guid(pb, &mediatype);
 384                     ff_get_guid(pb, &subtype);
 385                     url_fskip(pb, 12);
 386                     ff_get_guid(pb, &formattype);
 387                     size = get_le32(pb);
 388                     parse_media_type(s, 0, sid, mediatype, subtype, formattype, size);
 389                     consumed += 72 + size;
 390                 }
 391             }
 392         } else if (!ff_guidcmp(g, stream2_guid)) {
 393             int stream_index = ff_find_stream_index(s, sid);
 394             if (stream_index >= 0 && !((WtvStream*)s->streams[stream_index]->priv_data)->seen_data) {
 395                 ff_asf_guid mediatype, subtype, formattype;
 396                 int size;
 397                 url_fskip(pb, 12);
 398                 ff_get_guid(pb, &mediatype);
 399                 ff_get_guid(pb, &subtype);
 400                 url_fskip(pb, 12);
 401                 ff_get_guid(pb, &formattype);
 402                 size = get_le32(pb);
 403                 parse_media_type(s, s->streams[stream_index], sid, mediatype, subtype, formattype, size);
 404                 consumed += 76 + size;
 405             }
 406         } else if (!ff_guidcmp(g, EVENTID_AudioDescriptorSpanningEvent) ||
 407                    !ff_guidcmp(g, EVENTID_CtxADescriptorSpanningEvent) ||
 408                    !ff_guidcmp(g, EVENTID_CSDescriptorSpanningEvent) ||
 409                    !ff_guidcmp(g, EVENTID_StreamIDSpanningEvent) ||
 410                    !ff_guidcmp(g, EVENTID_SubtitleSpanningEvent) ||
 411                    !ff_guidcmp(g, EVENTID_TeletextSpanningEvent)) {
 412             int stream_index = ff_find_stream_index(s, sid);
 413             if (stream_index >= 0) {
 414                 AVStream *st = s->streams[stream_index];
 415                 uint8_t buf[258];
 416                 const uint8_t *pbuf = buf;
 417                 int buf_size;
 418
 419                 url_fskip(pb, 8);
 420                 consumed += 8;
 421                 if (!ff_guidcmp(g, EVENTID_CtxADescriptorSpanningEvent) ||
 422                     !ff_guidcmp(g, EVENTID_CSDescriptorSpanningEvent)) {
 423                     url_fskip(pb, 6);
 424                     consumed += 6;
 425                 }
 426
 427                 buf_size = FFMIN(len - consumed, sizeof(buf));
 428                 get_buffer(pb, buf, buf_size);
 429                 consumed += buf_size;
 430                 ff_parse_mpeg2_descriptor(s, st, 0, &pbuf, buf + buf_size, 0, 0, 0, 0);
 431             }
 432         } else if (!ff_guidcmp(g, EVENTID_DVBScramblingControlSpanningEvent)) {
 433             int stream_index = ff_find_stream_index(s, sid);
 434             if (stream_index >= 0) {
 435                 url_fskip(pb, 12);
 436                 if (get_le32(pb))
 437                     av_log(s, AV_LOG_WARNING, "DVB scrambled stream detected (st:%d), decoding will likely fail\n", stream_index);
 438                 consumed += 16;
 439             }
 440         } else if (!ff_guidcmp(g, EVENTID_LanguageSpanningEvent)) {
 441             int stream_index = ff_find_stream_index(s, sid);
 442             if (stream_index >= 0) {
 443                 AVStream *st = s->streams[stream_index];
 444                 uint8_t language[4];
 445                 url_fskip(pb, 12);
 446                 get_buffer(pb, language, 3);
 447                 if (language[0]) {
 448                     language[3] = 0;
 449                     av_metadata_set2(&st->metadata, "language", language, 0);
 450                 }
 451                 consumed += 15;
 452             }
 453         } else if (!ff_guidcmp(g, timestamp_guid)) {
 454             int stream_index = ff_find_stream_index(s, sid);
 455             if (stream_index >= 0) {
 456                 url_fskip(pb, 8);
 457                 wtv->pts = get_le64(pb);
 458                 consumed += 16;
 459                 if (wtv->pts == -1)
 460                     wtv->pts = AV_NOPTS_VALUE;
 461                 if (mode == SEEK_TO_PTS && wtv->pts >= seekts) {
 462 #define WTV_PAD8(x) (((x) + 7) & ~7)
 463                     url_fskip(pb, WTV_PAD8(len) - consumed);
 464                     return 0;
 465                 }
 466             }
 467         } else if (!ff_guidcmp(g, data_guid)) {
 468             int stream_index = ff_find_stream_index(s, sid);
 469             if (mode == SEEK_TO_DATA && stream_index >= 0) {
 470                 WtvStream *wst = s->streams[stream_index]->priv_data;
 471                 wst->seen_data = 1;
 472                 if (len_ptr) {
 473                     *len_ptr = len;
 474                 }
 475                 if (wtv->pts != AV_NOPTS_VALUE)
 476                     av_add_index_entry(s->streams[stream_index], url_ftell(pb) - consumed, wtv->pts, 0, 0, AVINDEX_KEYFRAME);
 477                 return stream_index;
 478             }
 479         } else if (
 480             !ff_guidcmp(g, /* DSATTRIB_CAPTURE_STREAMTIME */ (const ff_asf_guid){0x14,0x56,0x1A,0x0C,0xCD,0x30,0x40,0x4F,0xBC,0xBF,0xD0,0x3E,0x52,0x30,0x62,0x07}) ||
 481             !ff_guidcmp(g, /* DSATTRIB_PicSampleSeq */ (const ff_asf_guid){0x02,0xAE,0x5B,0x2F,0x8F,0x7B,0x60,0x4F,0x82,0xD6,0xE4,0xEA,0x2F,0x1F,0x4C,0x99}) ||
 482             !ff_guidcmp(g, /* DSATTRIB_TRANSPORT_PROPERTIES */ (const ff_asf_guid){0x12,0xF6,0x22,0xB6,0xAD,0x47,0x71,0x46,0xAD,0x6C,0x05,0xA9,0x8E,0x65,0xDE,0x3A}) ||
 483             !ff_guidcmp(g, /* dvr_ms_vid_frame_rep_data */ (const ff_asf_guid){0xCC,0x32,0x64,0xDD,0x29,0xE2,0xDB,0x40,0x80,0xF6,0xD2,0x63,0x28,0xD2,0x76,0x1F}) ||
 484             !ff_guidcmp(g, /* EVENTID_AudioTypeSpanningEvent */ (const ff_asf_guid){0xBE,0xBF,0x1C,0x50,0x49,0xB8,0xCE,0x42,0x9B,0xE9,0x3D,0xB8,0x69,0xFB,0x82,0xB3}) ||
 485             !ff_guidcmp(g, /* EVENTID_ChannelChangeSpanningEvent */ (const ff_asf_guid){0xE5,0xC5,0x67,0x90,0x5C,0x4C,0x05,0x42,0x86,0xC8,0x7A,0xFE,0x20,0xFE,0x1E,0xFA}) ||
 486             !ff_guidcmp(g, /* EVENTID_ChannelInfoSpanningEvent */ (const ff_asf_guid){0x80,0x6D,0xF3,0x41,0x32,0x41,0xC2,0x4C,0xB1,0x21,0x01,0xA4,0x32,0x19,0xD8,0x1B}) ||
 487             !ff_guidcmp(g, /* EVENTID_ChannelTypeSpanningEvent */ (const ff_asf_guid){0x51,0x1D,0xAB,0x72,0xD2,0x87,0x9B,0x48,0xBA,0x11,0x0E,0x08,0xDC,0x21,0x02,0x43}) ||
 488             !ff_guidcmp(g, /* EVENTID_PIDListSpanningEvent */ (const ff_asf_guid){0x65,0x8F,0xFC,0x47,0xBB,0xE2,0x34,0x46,0x9C,0xEF,0xFD,0xBF,0xE6,0x26,0x1D,0x5C}) ||
 489             !ff_guidcmp(g, /* EVENTID_SignalAndServiceStatusSpanningEvent */ (const ff_asf_guid){0xCB,0xC5,0x68,0x80,0x04,0x3C,0x2B,0x49,0xB4,0x7D,0x03,0x08,0x82,0x0D,0xCE,0x51}) ||
 490             !ff_guidcmp(g, /* EVENTID_StreamTypeSpanningEvent */ (const ff_asf_guid){0xBC,0x2E,0xAF,0x82,0xA6,0x30,0x64,0x42,0xA8,0x0B,0xAD,0x2E,0x13,0x72,0xAC,0x60}) ||
 491             !ff_guidcmp(g, (const ff_asf_guid){0x1E,0xBE,0xC3,0xC5,0x43,0x92,0xDC,0x11,0x85,0xE5,0x00,0x12,0x3F,0x6F,0x73,0xB9}) ||
 492             !ff_guidcmp(g, (const ff_asf_guid){0x3B,0x86,0xA2,0xB1,0xEB,0x1E,0xC3,0x44,0x8C,0x88,0x1C,0xA3,0xFF,0xE3,0xE7,0x6A}) ||
 493             !ff_guidcmp(g, (const ff_asf_guid){0x4E,0x7F,0x4C,0x5B,0xC4,0xD0,0x38,0x4B,0xA8,0x3E,0x21,0x7F,0x7B,0xBF,0x52,0xE7}) ||
 494             !ff_guidcmp(g, (const ff_asf_guid){0x63,0x36,0xEB,0xFE,0xA1,0x7E,0xD9,0x11,0x83,0x08,0x00,0x07,0xE9,0x5E,0xAD,0x8D}) ||
 495             !ff_guidcmp(g, (const ff_asf_guid){0x70,0xE9,0xF1,0xF8,0x89,0xA4,0x4C,0x4D,0x83,0x73,0xB8,0x12,0xE0,0xD5,0xF8,0x1E}) ||
 496             !ff_guidcmp(g, (const ff_asf_guid){0x96,0xC3,0xD2,0xC2,0x7E,0x9A,0xDA,0x11,0x8B,0xF7,0x00,0x07,0xE9,0x5E,0xAD,0x8D}) ||
 497             !ff_guidcmp(g, (const ff_asf_guid){0x97,0xC3,0xD2,0xC2,0x7E,0x9A,0xDA,0x11,0x8B,0xF7,0x00,0x07,0xE9,0x5E,0xAD,0x8D}) ||
 498             !ff_guidcmp(g, (const ff_asf_guid){0xA1,0xC3,0xD2,0xC2,0x7E,0x9A,0xDA,0x11,0x8B,0xF7,0x00,0x07,0xE9,0x5E,0xAD,0x8D})) {
 499             //ignore known guids
 500         } else
 501             av_log(s, AV_LOG_WARNING, "unsupported chunk:"PRI_GUID"\n", ARG_GUID(g));
 502
 503         url_fskip(pb, WTV_PAD8(len) - consumed);
 504     }
 505     return AVERROR_EOF;
 506 }
 507
 508 #define WTV_CHUNK_START 0x40000
 509
 510 static int read_header(AVFormatContext *s, AVFormatParameters *ap)
 511 {
 512     ByteIOContext *pb = s->pb;
 513     int ret;
 514
 515     url_fseek(pb, WTV_CHUNK_START, SEEK_SET);
 516     ret = parse_chunks(s, SEEK_TO_DATA, 0, 0);
 517     if (ret < 0)
 518         return ret;
 519
 520     url_fseek(pb, -32, SEEK_CUR);
 521     return 0;
 522 }
 523
 524 static int read_packet(AVFormatContext *s, AVPacket *pkt)
 525 {
 526     WtvContext *wtv = s->priv_data;
 527     ByteIOContext *pb = s->pb;
 528     int stream_index, len, ret;
 529
 530     stream_index = parse_chunks(s, SEEK_TO_DATA, 0, &len);
 531     if (stream_index < 0)
 532         return stream_index;
 533
 534     ret = av_get_packet(pb, pkt, len - 32);
 535     if (ret < 0)
 536         return ret;
 537     pkt->stream_index = stream_index;
 538     pkt->pts          = wtv->pts;
 539     url_fskip(pb, WTV_PAD8(len) - len);
 540     return 0;
 541 }
 542
 543 static int read_seek2(AVFormatContext *s, int stream_index,
 544                       int64_t min_ts, int64_t ts, int64_t max_ts, int flags)
 545 {
 546     WtvContext *wtv = s->priv_data;
 547     ByteIOContext *pb = s->pb;
 548     AVStream *st;
 549     int i;
 550
 551     if (stream_index < 0) {
 552         stream_index = av_find_default_stream_index(s);
 553         if (stream_index < 0)
 554             return -1;
 555     }
 556     st = s->streams[stream_index];
 557
 558     if ((flags & AVSEEK_FLAG_FRAME)) {
 559         return AVERROR_NOTSUPP;
 560     } else if ((flags & AVSEEK_FLAG_BYTE)) {
 561         if (ts < url_ftell(pb)) {
 562             for (i = st->nb_index_entries - 1; i >= 0; i--) {
 563                 if (st->index_entries[i].pos <= ts) {
 564                     wtv->pts    = st->index_entries[i].timestamp;
 565                     url_fseek(pb, st->index_entries[i].pos, SEEK_SET);
 566                     break;
 567                 }
 568             }
 569             if (i < 0) {
 570                 wtv->pts = 0;
 571                 url_fseek(pb, WTV_CHUNK_START, SEEK_SET);
 572             }
 573         }
 574         if (parse_chunks(s, SEEK_TO_BYTE, ts, 0) < 0)
 575             return AVERROR(ERANGE);
 576         return 0;
 577     } else {
 578         ts *= 10;
 579         i = av_index_search_timestamp(st, ts, flags);
 580         if (i < 0) {
 581             if (st->nb_index_entries > 0) {
 582                 wtv->pts    = st->index_entries[st->nb_index_entries - 1].timestamp;
 583                 url_fseek(pb, st->index_entries[st->nb_index_entries - 1].pos, SEEK_SET);
 584             } else {
 585                 wtv->pts = 0;
 586                 url_fseek(pb, WTV_CHUNK_START, SEEK_SET);
 587             }
 588             if (parse_chunks(s, SEEK_TO_PTS, ts, 0) < 0)
 589                 return AVERROR(ERANGE);
 590             return 0;
 591         }
 592         wtv->pts    = st->index_entries[i].timestamp;
 593         url_fseek(pb, st->index_entries[i].pos, SEEK_SET);
 594         return 0;
 595     }
 596 }
 597
 598 AVInputFormat wtv_demuxer = {
 599     .name           = "wtv",
 600     .long_name      = NULL_IF_CONFIG_SMALL("Windows Television (WTV)"),
 601     .priv_data_size = sizeof(WtvContext),
 602     .read_probe     = read_probe,
 603     .read_header    = read_header,
 604     .read_packet    = read_packet,
 605     .read_seek2     = read_seek2,
 606     .flags          = AVFMT_SHOW_IDS|AVFMT_TS_DISCONT,
 607 };