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, 32);
 170     st->codec->bit_rate = get_le32(pb);
 171     url_fskip(pb, 20);
 172     st->sample_aspect_ratio.num = get_le32(pb);
 173     st->sample_aspect_ratio.den = get_le32(pb);
 174     url_fskip(pb, 8);
 175     ff_get_bmp_header(pb, st);
 176
 177     return 72 + 40;
 178 }
 179
 180 /**
 181  * Parse MPEG1WAVEFORMATEX extradata structure
 182  */
 183 static void parse_mpeg1waveformatex(AVStream *st)
 184 {
 185     /* fwHeadLayer */
 186     switch (AV_RL16(st->codec->extradata)) {
 187     case 0x0001 : st->codec->codec_id = CODEC_ID_MP1; break;
 188     case 0x0002 : st->codec->codec_id = CODEC_ID_MP2; break;
 189     case 0x0004 : st->codec->codec_id = CODEC_ID_MP3; break;
 190     }
 191
 192     st->codec->bit_rate = AV_RL32(st->codec->extradata + 2); /* dwHeadBitrate */
 193
 194     /* dwHeadMode */
 195     switch (AV_RL16(st->codec->extradata + 6)) {
 196     case 1 : case 2 : case 4 : st->codec->channels = 2; break;
 197     case 8 :                   st->codec->channels = 1; break;
 198     }
 199 }
 200
 201 /**
 202  * Initialise stream
 203  * @param st Stream to initialise, or NULL to create and initialise new stream
 204  * @return NULL on error
 205  */
 206 static AVStream * new_stream(AVFormatContext *s, AVStream *st, int sid, int codec_type)
 207 {
 208     if (st) {
 209         if (st->codec->extradata) {
 210             av_freep(&st->codec->extradata);
 211             st->codec->extradata_size = 0;
 212         }
 213     } else {
 214         WtvStream *wst = av_mallocz(sizeof(WtvStream));
 215         if (!wst)
 216             return NULL;
 217         st = av_new_stream(s, sid);
 218         if (!st)
 219             return NULL;
 220         st->priv_data = wst;
 221     }
 222     st->codec->codec_type = codec_type;
 223     st->need_parsing      = AVSTREAM_PARSE_FULL;
 224     av_set_pts_info(st, 64, 1, 10000000);
 225     return st;
 226 }
 227
 228 /**
 229  * parse Media Type structure and populate stream
 230  * @param st         Stream, or NULL to create new stream
 231  * @param mediatype  Mediatype GUID
 232  * @param subtype    Subtype GUID
 233  * @param formattype Format GUID
 234  * @param size       Size of format buffer
 235  * @return NULL on error
 236  */
 237 static AVStream * parse_media_type(AVFormatContext *s, AVStream *st, int sid,
 238                                    ff_asf_guid mediatype, ff_asf_guid subtype,
 239                                    ff_asf_guid formattype, int size)
 240 {
 241     ByteIOContext *pb = s->pb;
 242     if (!ff_guidcmp(subtype, mediasubtype_cpfilters_processed) &&
 243         !ff_guidcmp(formattype, format_cpfilters_processed)) {
 244         ff_asf_guid actual_subtype;
 245         ff_asf_guid actual_formattype;
 246
 247         if (size < 32) {
 248             av_log(s, AV_LOG_WARNING, "format buffer size underflow\n");
 249             url_fskip(pb, size);
 250             return NULL;
 251         }
 252
 253         url_fskip(pb, size - 32);
 254         ff_get_guid(pb, &actual_subtype);
 255         ff_get_guid(pb, &actual_formattype);
 256         url_fseek(pb, -size, SEEK_CUR);
 257
 258         st = parse_media_type(s, st, sid, mediatype, actual_subtype, actual_formattype, size - 32);
 259         url_fskip(pb, 32);
 260         return st;
 261     } else if (!ff_guidcmp(mediatype, mediatype_audio)) {
 262         st = new_stream(s, st, sid, AVMEDIA_TYPE_AUDIO);
 263         if (!st)
 264             return NULL;
 265         if (!ff_guidcmp(formattype, format_waveformatex)) {
 266             ff_get_wav_header(pb, st->codec, size);
 267         } else {
 268             if (ff_guidcmp(formattype, format_none))
 269                 av_log(s, AV_LOG_WARNING, "unknown formattype:"PRI_GUID"\n", ARG_GUID(formattype));
 270             url_fskip(pb, size);
 271         }
 272
 273         if (!memcmp(subtype + 4, (const uint8_t[]){MEDIASUBTYPE_BASE_GUID}, 12)) {
 274             st->codec->codec_id = ff_wav_codec_get_id(AV_RL32(subtype), st->codec->bits_per_coded_sample);
 275         } else if (!ff_guidcmp(subtype, mediasubtype_mpeg1payload)) {
 276             if (st->codec->extradata && st->codec->extradata_size >= 22)
 277                 parse_mpeg1waveformatex(st);
 278             else
 279                 av_log(s, AV_LOG_WARNING, "MPEG1WAVEFORMATEX underflow\n");
 280         } else {
 281             st->codec->codec_id = ff_codec_guid_get_id(audio_guids, subtype);
 282             if (st->codec->codec_id == CODEC_ID_NONE)
 283                 av_log(s, AV_LOG_WARNING, "unknown subtype:"PRI_GUID"\n", ARG_GUID(subtype));
 284         }
 285         return st;
 286     } else if (!ff_guidcmp(mediatype, mediatype_video)) {
 287         st = new_stream(s, st, sid, AVMEDIA_TYPE_VIDEO);
 288         if (!st)
 289             return NULL;
 290         if (!ff_guidcmp(formattype, format_videoinfo2)) {
 291             int consumed = parse_videoinfoheader2(s, st);
 292             url_fskip(pb, FFMAX(size - consumed, 0));
 293         } else if (!ff_guidcmp(formattype, format_mpeg2_video)) {
 294             int consumed = parse_videoinfoheader2(s, st);
 295             url_fskip(pb, FFMAX(size - consumed, 0));
 296         } else {
 297             if (ff_guidcmp(formattype, format_none))
 298                 av_log(s, AV_LOG_WARNING, "unknown formattype:"PRI_GUID"\n", ARG_GUID(formattype));
 299             url_fskip(pb, size);
 300         }
 301
 302         if (!memcmp(subtype + 4, (const uint8_t[]){MEDIASUBTYPE_BASE_GUID}, 12)) {
 303             st->codec->codec_id = ff_codec_get_id(ff_codec_bmp_tags, AV_RL32(subtype));
 304         } else {
 305             st->codec->codec_id = ff_codec_guid_get_id(video_guids, subtype);
 306         }
 307         if (st->codec->codec_id == CODEC_ID_NONE)
 308             av_log(s, AV_LOG_WARNING, "unknown subtype:"PRI_GUID"\n", ARG_GUID(subtype));
 309         return st;
 310     } else if (!ff_guidcmp(mediatype, mediatype_mpeg2_pes) &&
 311                !ff_guidcmp(subtype, mediasubtype_dvb_subtitle)) {
 312         st = new_stream(s, st, sid, AVMEDIA_TYPE_SUBTITLE);
 313         if (!st)
 314             return NULL;
 315         if (ff_guidcmp(formattype, format_none))
 316             av_log(s, AV_LOG_WARNING, "unknown formattype:"PRI_GUID"\n", ARG_GUID(formattype));
 317         url_fskip(pb, size);
 318         st->codec->codec_id = CODEC_ID_DVB_SUBTITLE;
 319         return st;
 320     } else if (!ff_guidcmp(mediatype, mediatype_mstvcaption) &&
 321                (!ff_guidcmp(subtype, mediasubtype_teletext) || !ff_guidcmp(subtype, mediasubtype_dtvccdata))) {
 322         st = new_stream(s, st, sid, AVMEDIA_TYPE_SUBTITLE);
 323         if (!st)
 324             return NULL;
 325         if (ff_guidcmp(formattype, format_none))
 326             av_log(s, AV_LOG_WARNING, "unknown formattype:"PRI_GUID"\n", ARG_GUID(formattype));
 327         url_fskip(pb, size);
 328         st->codec->codec_id   = CODEC_ID_DVB_TELETEXT;
 329         return st;
 330     } else if (!ff_guidcmp(mediatype, mediatype_mpeg2_sections) &&
 331                !ff_guidcmp(subtype, mediasubtype_mpeg2_sections)) {
 332         if (ff_guidcmp(formattype, format_none))
 333             av_log(s, AV_LOG_WARNING, "unknown formattype:"PRI_GUID"\n", ARG_GUID(formattype));
 334         url_fskip(pb, size);
 335         return NULL;
 336     }
 337
 338     av_log(s, AV_LOG_WARNING, "unknown media type, mediatype:"PRI_GUID
 339                               ", subtype:"PRI_GUID", formattype:"PRI_GUID"\n",
 340                               ARG_GUID(mediatype), ARG_GUID(subtype), ARG_GUID(formattype));
 341     url_fskip(pb, size);
 342     return NULL;
 343 }
 344
 345 enum {
 346     SEEK_TO_DATA = 0,
 347     SEEK_TO_BYTE,
 348     SEEK_TO_PTS,
 349 };
 350
 351 /**
 352  * Parse WTV chunks
 353  * @param mode SEEK_TO_DATA, SEEK_TO_BYTE, SEEK_TO_PTS
 354  * @param seekts either byte position or timestamp
 355  * @param[out] len Length of data chunk
 356  * @return stream index of data chunk, or <0 on error
 357  */
 358 static int parse_chunks(AVFormatContext *s, int mode, int64_t seekts, int *len_ptr)
 359 {
 360     WtvContext *wtv = s->priv_data;
 361     ByteIOContext *pb = s->pb;
 362     while (!url_feof(pb)) {
 363         ff_asf_guid g;
 364         int len, sid, consumed;
 365
 366         if (mode == SEEK_TO_BYTE && url_ftell(pb) >= seekts)
 367             return 0;
 368
 369         ff_get_guid(pb, &g);
 370         if (is_zero(g, sizeof(ff_asf_guid)))
 371             return AVERROR_EOF;
 372
 373         len = get_le32(pb);
 374         if (len < 32)
 375             break;
 376         sid = get_le32(pb) & 0x7FFF;
 377         url_fskip(pb, 8);
 378         consumed = 32;
 379
 380         if (!ff_guidcmp(g, stream_guid)) {
 381             if (ff_find_stream_index(s, sid) < 0) {
 382                 ff_asf_guid mediatype, subtype, formattype;
 383                 int size;
 384                 consumed += 20;
 385                 url_fskip(pb, 16);
 386                 if (get_le32(pb)) {
 387                     url_fskip(pb, 8);
 388                     ff_get_guid(pb, &mediatype);
 389                     ff_get_guid(pb, &subtype);
 390                     url_fskip(pb, 12);
 391                     ff_get_guid(pb, &formattype);
 392                     size = get_le32(pb);
 393                     parse_media_type(s, 0, sid, mediatype, subtype, formattype, size);
 394                     consumed += 72 + size;
 395                 }
 396             }
 397         } else if (!ff_guidcmp(g, stream2_guid)) {
 398             int stream_index = ff_find_stream_index(s, sid);
 399             if (stream_index >= 0 && !((WtvStream*)s->streams[stream_index]->priv_data)->seen_data) {
 400                 ff_asf_guid mediatype, subtype, formattype;
 401                 int size;
 402                 url_fskip(pb, 12);
 403                 ff_get_guid(pb, &mediatype);
 404                 ff_get_guid(pb, &subtype);
 405                 url_fskip(pb, 12);
 406                 ff_get_guid(pb, &formattype);
 407                 size = get_le32(pb);
 408                 parse_media_type(s, s->streams[stream_index], sid, mediatype, subtype, formattype, size);
 409                 consumed += 76 + size;
 410             }
 411         } else if (!ff_guidcmp(g, EVENTID_AudioDescriptorSpanningEvent) ||
 412                    !ff_guidcmp(g, EVENTID_CtxADescriptorSpanningEvent) ||
 413                    !ff_guidcmp(g, EVENTID_CSDescriptorSpanningEvent) ||
 414                    !ff_guidcmp(g, EVENTID_StreamIDSpanningEvent) ||
 415                    !ff_guidcmp(g, EVENTID_SubtitleSpanningEvent) ||
 416                    !ff_guidcmp(g, EVENTID_TeletextSpanningEvent)) {
 417             int stream_index = ff_find_stream_index(s, sid);
 418             if (stream_index >= 0) {
 419                 AVStream *st = s->streams[stream_index];
 420                 uint8_t buf[258];
 421                 const uint8_t *pbuf = buf;
 422                 int buf_size;
 423
 424                 url_fskip(pb, 8);
 425                 consumed += 8;
 426                 if (!ff_guidcmp(g, EVENTID_CtxADescriptorSpanningEvent) ||
 427                     !ff_guidcmp(g, EVENTID_CSDescriptorSpanningEvent)) {
 428                     url_fskip(pb, 6);
 429                     consumed += 6;
 430                 }
 431
 432                 buf_size = FFMIN(len - consumed, sizeof(buf));
 433                 get_buffer(pb, buf, buf_size);
 434                 consumed += buf_size;
 435                 ff_parse_mpeg2_descriptor(s, st, 0, &pbuf, buf + buf_size, 0, 0, 0, 0);
 436             }
 437         } else if (!ff_guidcmp(g, EVENTID_DVBScramblingControlSpanningEvent)) {
 438             int stream_index = ff_find_stream_index(s, sid);
 439             if (stream_index >= 0) {
 440                 url_fskip(pb, 12);
 441                 if (get_le32(pb))
 442                     av_log(s, AV_LOG_WARNING, "DVB scrambled stream detected (st:%d), decoding will likely fail\n", stream_index);
 443                 consumed += 16;
 444             }
 445         } else if (!ff_guidcmp(g, EVENTID_LanguageSpanningEvent)) {
 446             int stream_index = ff_find_stream_index(s, sid);
 447             if (stream_index >= 0) {
 448                 AVStream *st = s->streams[stream_index];
 449                 uint8_t language[4];
 450                 url_fskip(pb, 12);
 451                 get_buffer(pb, language, 3);
 452                 if (language[0]) {
 453                     language[3] = 0;
 454                     av_metadata_set2(&st->metadata, "language", language, 0);
 455                 }
 456                 consumed += 15;
 457             }
 458         } else if (!ff_guidcmp(g, timestamp_guid)) {
 459             url_fskip(pb, 8);
 460             wtv->pts = get_le64(pb);
 461             consumed += 16;
 462             if (wtv->pts == -1)
 463                 wtv->pts = AV_NOPTS_VALUE;
 464             if (mode == SEEK_TO_PTS && wtv->pts >= seekts) {
 465 #define WTV_PAD8(x) (((x) + 7) & ~7)
 466                 url_fskip(pb, WTV_PAD8(len) - consumed);
 467                 return 0;
 468             }
 469         } else if (!ff_guidcmp(g, data_guid)) {
 470             int stream_index = ff_find_stream_index(s, sid);
 471             if (mode == SEEK_TO_DATA && stream_index >= 0) {
 472                 WtvStream *wst = s->streams[stream_index]->priv_data;
 473                 wst->seen_data = 1;
 474                 if (len_ptr) {
 475                     *len_ptr = len;
 476                 }
 477                 if (wtv->pts != AV_NOPTS_VALUE)
 478                     av_add_index_entry(s->streams[stream_index], url_ftell(pb) - consumed, wtv->pts, 0, 0, AVINDEX_KEYFRAME);
 479                 return stream_index;
 480             }
 481         } else if (
 482             !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}) ||
 483             !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}) ||
 484             !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}) ||
 485             !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}) ||
 486             !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}) ||
 487             !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}) ||
 488             !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}) ||
 489             !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}) ||
 490             !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}) ||
 491             !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}) ||
 492             !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}) ||
 493             !ff_guidcmp(g, (const ff_asf_guid){0x1E,0xBE,0xC3,0xC5,0x43,0x92,0xDC,0x11,0x85,0xE5,0x00,0x12,0x3F,0x6F,0x73,0xB9}) ||
 494             !ff_guidcmp(g, (const ff_asf_guid){0x3B,0x86,0xA2,0xB1,0xEB,0x1E,0xC3,0x44,0x8C,0x88,0x1C,0xA3,0xFF,0xE3,0xE7,0x6A}) ||
 495             !ff_guidcmp(g, (const ff_asf_guid){0x4E,0x7F,0x4C,0x5B,0xC4,0xD0,0x38,0x4B,0xA8,0x3E,0x21,0x7F,0x7B,0xBF,0x52,0xE7}) ||
 496             !ff_guidcmp(g, (const ff_asf_guid){0x63,0x36,0xEB,0xFE,0xA1,0x7E,0xD9,0x11,0x83,0x08,0x00,0x07,0xE9,0x5E,0xAD,0x8D}) ||
 497             !ff_guidcmp(g, (const ff_asf_guid){0x70,0xE9,0xF1,0xF8,0x89,0xA4,0x4C,0x4D,0x83,0x73,0xB8,0x12,0xE0,0xD5,0xF8,0x1E}) ||
 498             !ff_guidcmp(g, (const ff_asf_guid){0x96,0xC3,0xD2,0xC2,0x7E,0x9A,0xDA,0x11,0x8B,0xF7,0x00,0x07,0xE9,0x5E,0xAD,0x8D}) ||
 499             !ff_guidcmp(g, (const ff_asf_guid){0x97,0xC3,0xD2,0xC2,0x7E,0x9A,0xDA,0x11,0x8B,0xF7,0x00,0x07,0xE9,0x5E,0xAD,0x8D}) ||
 500             !ff_guidcmp(g, (const ff_asf_guid){0xA1,0xC3,0xD2,0xC2,0x7E,0x9A,0xDA,0x11,0x8B,0xF7,0x00,0x07,0xE9,0x5E,0xAD,0x8D})) {
 501             //ignore known guids
 502         } else
 503             av_log(s, AV_LOG_WARNING, "unsupported chunk:"PRI_GUID"\n", ARG_GUID(g));
 504
 505         url_fskip(pb, WTV_PAD8(len) - consumed);
 506     }
 507     return AVERROR_EOF;
 508 }
 509
 510 #define WTV_CHUNK_START 0x40000
 511
 512 static int read_header(AVFormatContext *s, AVFormatParameters *ap)
 513 {
 514     ByteIOContext *pb = s->pb;
 515     int ret;
 516
 517     url_fseek(pb, WTV_CHUNK_START, SEEK_SET);
 518     ret = parse_chunks(s, SEEK_TO_DATA, 0, 0);
 519     if (ret < 0)
 520         return ret;
 521
 522     url_fseek(pb, -32, SEEK_CUR);
 523     return 0;
 524 }
 525
 526 static int read_packet(AVFormatContext *s, AVPacket *pkt)
 527 {
 528     WtvContext *wtv = s->priv_data;
 529     ByteIOContext *pb = s->pb;
 530     int stream_index, len, ret;
 531
 532     stream_index = parse_chunks(s, SEEK_TO_DATA, 0, &len);
 533     if (stream_index < 0)
 534         return stream_index;
 535
 536     ret = av_get_packet(pb, pkt, len - 32);
 537     if (ret < 0)
 538         return ret;
 539     pkt->stream_index = stream_index;
 540     pkt->pts          = wtv->pts;
 541     url_fskip(pb, WTV_PAD8(len) - len);
 542     return 0;
 543 }
 544
 545 static int read_seek2(AVFormatContext *s, int stream_index,
 546                       int64_t min_ts, int64_t ts, int64_t max_ts, int flags)
 547 {
 548     WtvContext *wtv = s->priv_data;
 549     ByteIOContext *pb = s->pb;
 550     AVStream *st;
 551     int i;
 552
 553     if (stream_index < 0) {
 554         stream_index = av_find_default_stream_index(s);
 555         if (stream_index < 0)
 556             return -1;
 557     }
 558     st = s->streams[stream_index];
 559
 560     if ((flags & AVSEEK_FLAG_FRAME)) {
 561         return AVERROR_NOTSUPP;
 562     } else if ((flags & AVSEEK_FLAG_BYTE)) {
 563         if (ts < url_ftell(pb)) {
 564             for (i = st->nb_index_entries - 1; i >= 0; i--) {
 565                 if (st->index_entries[i].pos <= ts) {
 566                     wtv->pts    = st->index_entries[i].timestamp;
 567                     url_fseek(pb, st->index_entries[i].pos, SEEK_SET);
 568                     break;
 569                 }
 570             }
 571             if (i < 0) {
 572                 wtv->pts = 0;
 573                 url_fseek(pb, WTV_CHUNK_START, SEEK_SET);
 574             }
 575         }
 576         if (parse_chunks(s, SEEK_TO_BYTE, ts, 0) < 0)
 577             return AVERROR(ERANGE);
 578         return 0;
 579     } else {
 580         ts *= 10;
 581         i = av_index_search_timestamp(st, ts, flags);
 582         if (i < 0) {
 583             if (st->nb_index_entries > 0) {
 584                 wtv->pts    = st->index_entries[st->nb_index_entries - 1].timestamp;
 585                 url_fseek(pb, st->index_entries[st->nb_index_entries - 1].pos, SEEK_SET);
 586             } else {
 587                 wtv->pts = 0;
 588                 url_fseek(pb, WTV_CHUNK_START, SEEK_SET);
 589             }
 590             if (parse_chunks(s, SEEK_TO_PTS, ts, 0) < 0)
 591                 return AVERROR(ERANGE);
 592             return 0;
 593         }
 594         wtv->pts    = st->index_entries[i].timestamp;
 595         url_fseek(pb, st->index_entries[i].pos, SEEK_SET);
 596         return 0;
 597     }
 598 }
 599
 600 AVInputFormat wtv_demuxer = {
 601     .name           = "wtv",
 602     .long_name      = NULL_IF_CONFIG_SMALL("Windows Television (WTV)"),
 603     .priv_data_size = sizeof(WtvContext),
 604     .read_probe     = read_probe,
 605     .read_header    = read_header,
 606     .read_packet    = read_packet,
 607     .read_seek2     = read_seek2,
 608     .flags          = AVFMT_SHOW_IDS|AVFMT_TS_DISCONT,
 609 };