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   1 /*
   2  * Windows Television (WTV) demuxer
   3  * Copyright (c) 2010-2011 Peter Ross <pross@xvid.org>
   4  *
   5  * This file is part of Libav.
   6  *
   7  * Libav 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  * Libav 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 Libav; 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/channel_layout.h"
  29 #include "libavutil/intreadwrite.h"
  30 #include "libavutil/intfloat.h"
  31 #include "libavutil/dict.h"
  32 #include "avformat.h"
  33 #include "internal.h"
  34 #include "riff.h"
  35 #include "asf.h"
  36 #include "mpegts.h"
  37
  38 /* Macros for formating GUIDs */
  39 #define PRI_PRETTY_GUID \
  40     "%08x-%04x-%04x-%02x%02x%02x%02x%02x%02x%02x%02x"
  41 #define ARG_PRETTY_GUID(g) \
  42     AV_RL32(g),AV_RL16(g+4),AV_RL16(g+6),g[8],g[9],g[10],g[11],g[12],g[13],g[14],g[15]
  43 #define LEN_PRETTY_GUID 34
  44
  45 /*
  46  *
  47  * File system routines
  48  *
  49  */
  50
  51 #define WTV_SECTOR_BITS    INT64_C(12)
  52 #define WTV_SECTOR_SIZE    (1 << WTV_SECTOR_BITS)
  53 #define WTV_BIGSECTOR_BITS 18
  54
  55 typedef struct {
  56     AVIOContext *pb_filesystem;  /** file system (AVFormatContext->pb) */
  57
  58     int sector_bits;     /** sector shift bits; used to convert sector number into pb_filesystem offset */
  59     uint32_t *sectors;   /** file allocation table */
  60     int nb_sectors;      /** number of sectors */
  61
  62     int error;
  63     int64_t position;
  64     int64_t length;
  65 } WtvFile;
  66
  67 /**
  68  * @return bytes read, 0 on end of file, or <0 on error
  69  */
  70 static int wtvfile_read_packet(void *opaque, uint8_t *buf, int buf_size)
  71 {
  72     WtvFile *wf = opaque;
  73     AVIOContext *pb = wf->pb_filesystem;
  74     int nread = 0;
  75
  76     if (wf->error || pb->error)
  77         return -1;
  78     if (wf->position >= wf->length || pb->eof_reached)
  79         return 0;
  80
  81     buf_size = FFMIN(buf_size, wf->length - wf->position);
  82     while(nread < buf_size) {
  83         int n;
  84         int remaining_in_sector = (1 << wf->sector_bits) - (wf->position & ((1 << wf->sector_bits) - 1));
  85         int read_request        = FFMIN(buf_size - nread, remaining_in_sector);
  86
  87         n = avio_read(pb, buf, read_request);
  88         if (n <= 0)
  89             break;
  90         nread += n;
  91         buf += n;
  92         wf->position += n;
  93         if (n == remaining_in_sector) {
  94             int i = wf->position >> wf->sector_bits;
  95             if (i >= wf->nb_sectors ||
  96                 (wf->sectors[i] != wf->sectors[i - 1] + (1 << (wf->sector_bits - WTV_SECTOR_BITS)) &&
  97                 avio_seek(pb, wf->sectors[i] << WTV_SECTOR_BITS, SEEK_SET) < 0)) {
  98                 wf->error = 1;
  99                 break;
 100             }
 101         }
 102     }
 103     return nread;
 104 }
 105
 106 /**
 107  * @return position (or file length)
 108  */
 109 static int64_t wtvfile_seek(void *opaque, int64_t offset, int whence)
 110 {
 111     WtvFile *wf = opaque;
 112     AVIOContext *pb = wf->pb_filesystem;
 113
 114     if (whence == AVSEEK_SIZE)
 115         return wf->length;
 116     else if (whence == SEEK_CUR)
 117         offset = wf->position + offset;
 118     else if (whence == SEEK_END)
 119         offset = wf->length;
 120
 121     wf->error = offset < 0 || offset >= wf->length ||
 122                 avio_seek(pb, (wf->sectors[offset >> wf->sector_bits] << WTV_SECTOR_BITS)
 123                               + (offset & ((1 << wf->sector_bits) - 1)), SEEK_SET) < 0;
 124     wf->position = offset;
 125     return offset;
 126 }
 127
 128 /**
 129  * read non-zero integers (le32) from input stream
 130  * @param pb
 131  * @param[out] data destination
 132  * @param     count maximum number of integers to read
 133  * @return    total number of integers read
 134  */
 135 static int read_ints(AVIOContext *pb, uint32_t *data, int count)
 136 {
 137     int i, total = 0;
 138     for (i = 0; i < count; i++) {
 139         if ((data[total] = avio_rl32(pb)))
 140            total++;
 141     }
 142     return total;
 143 }
 144
 145 /**
 146  * Open file
 147  * @param first_sector  First sector
 148  * @param length        Length of file (bytes)
 149  * @param depth         File allocation table depth
 150  * @return NULL on error
 151  */
 152 static AVIOContext * wtvfile_open_sector(int first_sector, uint64_t length, int depth, AVFormatContext *s)
 153 {
 154     AVIOContext *pb;
 155     WtvFile *wf;
 156     uint8_t *buffer;
 157
 158     if (avio_seek(s->pb, first_sector << WTV_SECTOR_BITS, SEEK_SET) < 0)
 159         return NULL;
 160
 161     wf = av_mallocz(sizeof(WtvFile));
 162     if (!wf)
 163         return NULL;
 164
 165     if (depth == 0) {
 166         wf->sectors = av_malloc(sizeof(uint32_t));
 167         if (!wf->sectors) {
 168             av_free(wf);
 169             return NULL;
 170         }
 171         wf->sectors[0]  = first_sector;
 172         wf->nb_sectors  = 1;
 173         wf->sector_bits = WTV_SECTOR_BITS;
 174     } else if (depth == 1) {
 175         wf->sectors = av_malloc(WTV_SECTOR_SIZE);
 176         if (!wf->sectors) {
 177             av_free(wf);
 178             return NULL;
 179         }
 180         wf->nb_sectors  = read_ints(s->pb, wf->sectors, WTV_SECTOR_SIZE / 4);
 181         wf->sector_bits = length & (1ULL<<63) ? WTV_SECTOR_BITS : WTV_BIGSECTOR_BITS;
 182     } else if (depth == 2) {
 183         uint32_t sectors1[WTV_SECTOR_SIZE / 4];
 184         int nb_sectors1 = read_ints(s->pb, sectors1, WTV_SECTOR_SIZE / 4);
 185         int i;
 186
 187         wf->sectors = av_malloc(nb_sectors1 << WTV_SECTOR_BITS);
 188         if (!wf->sectors) {
 189             av_free(wf);
 190             return NULL;
 191         }
 192         wf->nb_sectors = 0;
 193         for (i = 0; i < nb_sectors1; i++) {
 194             if (avio_seek(s->pb, sectors1[i] << WTV_SECTOR_BITS, SEEK_SET) < 0)
 195                 break;
 196             wf->nb_sectors += read_ints(s->pb, wf->sectors + i * WTV_SECTOR_SIZE / 4, WTV_SECTOR_SIZE / 4);
 197         }
 198         wf->sector_bits = length & (1ULL<<63) ? WTV_SECTOR_BITS : WTV_BIGSECTOR_BITS;
 199     } else {
 200         av_log(s, AV_LOG_ERROR, "unsupported file allocation table depth (0x%x)\n", depth);
 201         av_free(wf);
 202         return NULL;
 203     }
 204
 205     if (!wf->nb_sectors) {
 206         av_free(wf->sectors);
 207         av_free(wf);
 208         return NULL;
 209     }
 210
 211     /* check length */
 212     length &= 0xFFFFFFFFFFFF;
 213     if (length > ((int64_t)wf->nb_sectors << wf->sector_bits)) {
 214         av_log(s, AV_LOG_WARNING, "reported file length (0x%"PRIx64") exceeds number of available sectors (0x%"PRIx64")\n", length, (int64_t)wf->nb_sectors << wf->sector_bits);
 215         length = (int64_t)wf->nb_sectors <<  wf->sector_bits;
 216     }
 217     wf->length = length;
 218
 219     /* seek to initial sector */
 220     wf->position = 0;
 221     if (avio_seek(s->pb, wf->sectors[0] << WTV_SECTOR_BITS, SEEK_SET) < 0) {
 222         av_free(wf->sectors);
 223         av_free(wf);
 224         return NULL;
 225     }
 226
 227     wf->pb_filesystem = s->pb;
 228     buffer = av_malloc(1 << wf->sector_bits);
 229     if (!buffer) {
 230         av_free(wf->sectors);
 231         av_free(wf);
 232         return NULL;
 233     }
 234
 235     pb = avio_alloc_context(buffer, 1 << wf->sector_bits, 0, wf,
 236                            wtvfile_read_packet, NULL, wtvfile_seek);
 237     if (!pb) {
 238         av_free(buffer);
 239         av_free(wf->sectors);
 240         av_free(wf);
 241     }
 242     return pb;
 243 }
 244
 245 static const ff_asf_guid dir_entry_guid =
 246     {0x92,0xB7,0x74,0x91,0x59,0x70,0x70,0x44,0x88,0xDF,0x06,0x3B,0x82,0xCC,0x21,0x3D};
 247
 248 /**
 249  * Open file using filename
 250  * @param[in]  buf       directory buffer
 251  * @param      buf_size  directory buffer size
 252  * @param[in]  filename
 253  * @param      filename_size size of filename
 254  * @return NULL on error
 255  */
 256 static AVIOContext * wtvfile_open2(AVFormatContext *s, const uint8_t *buf, int buf_size, const uint8_t *filename, int filename_size)
 257 {
 258     const uint8_t *buf_end = buf + buf_size;
 259
 260     while(buf + 48 <= buf_end) {
 261         int dir_length, name_size, first_sector, depth;
 262         uint64_t file_length;
 263         const uint8_t *name;
 264         if (ff_guidcmp(buf, dir_entry_guid)) {
 265             av_log(s, AV_LOG_ERROR, "unknown guid "FF_PRI_GUID", expected dir_entry_guid; "
 266                    "remaining directory entries ignored\n", FF_ARG_GUID(buf));
 267             break;
 268         }
 269         dir_length  = AV_RL16(buf + 16);
 270         file_length = AV_RL64(buf + 24);
 271         name_size   = 2 * AV_RL32(buf + 32);
 272         if (buf + 48 + name_size > buf_end) {
 273             av_log(s, AV_LOG_ERROR, "filename exceeds buffer size; remaining directory entries ignored\n");
 274             break;
 275         }
 276         first_sector = AV_RL32(buf + 40 + name_size);
 277         depth        = AV_RL32(buf + 44 + name_size);
 278
 279         /* compare file name; test optional null terminator */
 280         name = buf + 40;
 281         if (name_size >= filename_size &&
 282             !memcmp(name, filename, filename_size) &&
 283             (name_size < filename_size + 2 || !AV_RN16(name + filename_size)))
 284             return wtvfile_open_sector(first_sector, file_length, depth, s);
 285
 286         buf += dir_length;
 287     }
 288     return 0;
 289 }
 290
 291 #define wtvfile_open(s, buf, buf_size, filename) \
 292     wtvfile_open2(s, buf, buf_size, filename, sizeof(filename))
 293
 294 /**
 295  * Close file opened with wtvfile_open_sector(), or wtv_open()
 296  */
 297 static void wtvfile_close(AVIOContext *pb)
 298 {
 299     WtvFile *wf = pb->opaque;
 300     av_free(wf->sectors);
 301     av_free(wf);
 302     av_free(pb->buffer);
 303     av_free(pb);
 304 }
 305
 306 /*
 307  *
 308  * Main demuxer
 309  *
 310  */
 311
 312 typedef struct {
 313     int seen_data;
 314 } WtvStream;
 315
 316 typedef struct {
 317     AVIOContext *pb;       /** timeline file */
 318     int64_t epoch;
 319     int64_t pts;             /** pts for next data chunk */
 320     int64_t last_valid_pts;  /** latest valid pts, used for interative seeking */
 321
 322     /* maintain private seek index, as the AVIndexEntry->pos is relative to the
 323        start of the 'timeline' file, not the file system (AVFormatContext->pb) */
 324     AVIndexEntry *index_entries;
 325     int nb_index_entries;
 326     unsigned int index_entries_allocated_size;
 327 } WtvContext;
 328
 329 /* WTV GUIDs */
 330 static const ff_asf_guid wtv_guid =
 331     {0xB7,0xD8,0x00,0x20,0x37,0x49,0xDA,0x11,0xA6,0x4E,0x00,0x07,0xE9,0x5E,0xAD,0x8D};
 332 static const ff_asf_guid metadata_guid =
 333     {0x5A,0xFE,0xD7,0x6D,0xC8,0x1D,0x8F,0x4A,0x99,0x22,0xFA,0xB1,0x1C,0x38,0x14,0x53};
 334 static const ff_asf_guid timestamp_guid =
 335     {0x5B,0x05,0xE6,0x1B,0x97,0xA9,0x49,0x43,0x88,0x17,0x1A,0x65,0x5A,0x29,0x8A,0x97};
 336 static const ff_asf_guid data_guid =
 337     {0x95,0xC3,0xD2,0xC2,0x7E,0x9A,0xDA,0x11,0x8B,0xF7,0x00,0x07,0xE9,0x5E,0xAD,0x8D};
 338 static const ff_asf_guid stream_guid =
 339     {0xED,0xA4,0x13,0x23,0x2D,0xBF,0x4F,0x45,0xAD,0x8A,0xD9,0x5B,0xA7,0xF9,0x1F,0xEE};
 340 static const ff_asf_guid stream2_guid =
 341     {0xA2,0xC3,0xD2,0xC2,0x7E,0x9A,0xDA,0x11,0x8B,0xF7,0x00,0x07,0xE9,0x5E,0xAD,0x8D};
 342 static const ff_asf_guid EVENTID_SubtitleSpanningEvent =
 343     {0x48,0xC0,0xCE,0x5D,0xB9,0xD0,0x63,0x41,0x87,0x2C,0x4F,0x32,0x22,0x3B,0xE8,0x8A};
 344 static const ff_asf_guid EVENTID_LanguageSpanningEvent =
 345     {0x6D,0x66,0x92,0xE2,0x02,0x9C,0x8D,0x44,0xAA,0x8D,0x78,0x1A,0x93,0xFD,0xC3,0x95};
 346 static const ff_asf_guid EVENTID_AudioDescriptorSpanningEvent =
 347     {0x1C,0xD4,0x7B,0x10,0xDA,0xA6,0x91,0x46,0x83,0x69,0x11,0xB2,0xCD,0xAA,0x28,0x8E};
 348 static const ff_asf_guid EVENTID_CtxADescriptorSpanningEvent =
 349     {0xE6,0xA2,0xB4,0x3A,0x47,0x42,0x34,0x4B,0x89,0x6C,0x30,0xAF,0xA5,0xD2,0x1C,0x24};
 350 static const ff_asf_guid EVENTID_CSDescriptorSpanningEvent =
 351     {0xD9,0x79,0xE7,0xEf,0xF0,0x97,0x86,0x47,0x80,0x0D,0x95,0xCF,0x50,0x5D,0xDC,0x66};
 352 static const ff_asf_guid EVENTID_DVBScramblingControlSpanningEvent =
 353     {0xC4,0xE1,0xD4,0x4B,0xA1,0x90,0x09,0x41,0x82,0x36,0x27,0xF0,0x0E,0x7D,0xCC,0x5B};
 354 static const ff_asf_guid EVENTID_StreamIDSpanningEvent =
 355     {0x68,0xAB,0xF1,0xCA,0x53,0xE1,0x41,0x4D,0xA6,0xB3,0xA7,0xC9,0x98,0xDB,0x75,0xEE};
 356 static const ff_asf_guid EVENTID_TeletextSpanningEvent =
 357     {0x50,0xD9,0x99,0x95,0x33,0x5F,0x17,0x46,0xAF,0x7C,0x1E,0x54,0xB5,0x10,0xDA,0xA3};
 358 static const ff_asf_guid EVENTID_AudioTypeSpanningEvent =
 359     {0xBE,0xBF,0x1C,0x50,0x49,0xB8,0xCE,0x42,0x9B,0xE9,0x3D,0xB8,0x69,0xFB,0x82,0xB3};
 360
 361 /* Windows media GUIDs */
 362
 363 /* Media types */
 364 static const ff_asf_guid mediatype_audio =
 365     {'a','u','d','s',FF_MEDIASUBTYPE_BASE_GUID};
 366 static const ff_asf_guid mediatype_video =
 367     {'v','i','d','s',FF_MEDIASUBTYPE_BASE_GUID};
 368 static const ff_asf_guid mediasubtype_mpeg1payload =
 369     {0x81,0xEB,0x36,0xE4,0x4F,0x52,0xCE,0x11,0x9F,0x53,0x00,0x20,0xAF,0x0B,0xA7,0x70};
 370 static const ff_asf_guid mediatype_mpeg2_sections =
 371     {0x6C,0x17,0x5F,0x45,0x06,0x4B,0xCE,0x47,0x9A,0xEF,0x8C,0xAE,0xF7,0x3D,0xF7,0xB5};
 372 static const ff_asf_guid mediatype_mpeg2_pes =
 373     {0x20,0x80,0x6D,0xE0,0x46,0xDB,0xCF,0x11,0xB4,0xD1,0x00,0x80,0x5F,0x6C,0xBB,0xEA};
 374 static const ff_asf_guid mediatype_mstvcaption =
 375     {0x89,0x8A,0x8B,0xB8,0x49,0xB0,0x80,0x4C,0xAD,0xCF,0x58,0x98,0x98,0x5E,0x22,0xC1};
 376
 377 /* Media subtypes */
 378 static const ff_asf_guid mediasubtype_cpfilters_processed =
 379     {0x28,0xBD,0xAD,0x46,0xD0,0x6F,0x96,0x47,0x93,0xB2,0x15,0x5C,0x51,0xDC,0x04,0x8D};
 380 static const ff_asf_guid mediasubtype_dvb_subtitle =
 381     {0xC3,0xCB,0xFF,0x34,0xB3,0xD5,0x71,0x41,0x90,0x02,0xD4,0xC6,0x03,0x01,0x69,0x7F};
 382 static const ff_asf_guid mediasubtype_teletext =
 383     {0xE3,0x76,0x2A,0xF7,0x0A,0xEB,0xD0,0x11,0xAC,0xE4,0x00,0x00,0xC0,0xCC,0x16,0xBA};
 384 static const ff_asf_guid mediasubtype_dtvccdata =
 385     {0xAA,0xDD,0x2A,0xF5,0xF0,0x36,0xF5,0x43,0x95,0xEA,0x6D,0x86,0x64,0x84,0x26,0x2A};
 386 static const ff_asf_guid mediasubtype_mpeg2_sections =
 387     {0x79,0x85,0x9F,0x4A,0xF8,0x6B,0x92,0x43,0x8A,0x6D,0xD2,0xDD,0x09,0xFA,0x78,0x61};
 388
 389 /* Formats */
 390 static const ff_asf_guid format_cpfilters_processed =
 391     {0x6F,0xB3,0x39,0x67,0x5F,0x1D,0xC2,0x4A,0x81,0x92,0x28,0xBB,0x0E,0x73,0xD1,0x6A};
 392 static const ff_asf_guid format_waveformatex =
 393     {0x81,0x9F,0x58,0x05,0x56,0xC3,0xCE,0x11,0xBF,0x01,0x00,0xAA,0x00,0x55,0x59,0x5A};
 394 static const ff_asf_guid format_videoinfo2 =
 395     {0xA0,0x76,0x2A,0xF7,0x0A,0xEB,0xD0,0x11,0xAC,0xE4,0x00,0x00,0xC0,0xCC,0x16,0xBA};
 396 static const ff_asf_guid format_mpeg2_video =
 397     {0xE3,0x80,0x6D,0xE0,0x46,0xDB,0xCF,0x11,0xB4,0xD1,0x00,0x80,0x5F,0x6C,0xBB,0xEA};
 398 static const ff_asf_guid format_none =
 399     {0xD6,0x17,0x64,0x0F,0x18,0xC3,0xD0,0x11,0xA4,0x3F,0x00,0xA0,0xC9,0x22,0x31,0x96};
 400
 401 static const AVCodecGuid video_guids[] = {
 402     {AV_CODEC_ID_MPEG2VIDEO, {0x26,0x80,0x6D,0xE0,0x46,0xDB,0xCF,0x11,0xB4,0xD1,0x00,0x80,0x5F,0x6C,0xBB,0xEA}},
 403     {AV_CODEC_ID_NONE}
 404 };
 405
 406 static int read_probe(AVProbeData *p)
 407 {
 408     return ff_guidcmp(p->buf, wtv_guid) ? 0 : AVPROBE_SCORE_MAX;
 409 }
 410
 411 /**
 412  * Convert win32 FILETIME to ISO-8601 string
 413  */
 414 static void filetime_to_iso8601(char *buf, int buf_size, int64_t value)
 415 {
 416     time_t t = (value / 10000000LL) - 11644473600LL;
 417     struct tm *tm = gmtime(&t);
 418     if (tm)
 419         strftime(buf, buf_size, "%Y-%m-%d %H:%M:%S", gmtime(&t));
 420     else
 421         buf[0] = '\0';
 422 }
 423
 424 /**
 425  * Convert crazy time (100ns since 1 Jan 0001) to ISO-8601 string
 426  */
 427 static void crazytime_to_iso8601(char *buf, int buf_size, int64_t value)
 428 {
 429     time_t t = (value / 10000000LL) - 719162LL*86400LL;
 430     struct tm *tm = gmtime(&t);
 431     if (tm)
 432         strftime(buf, buf_size, "%Y-%m-%d %H:%M:%S", gmtime(&t));
 433     else
 434         buf[0] = '\0';
 435 }
 436
 437 /**
 438  * Convert OLE DATE to ISO-8601 string
 439  */
 440 static void oledate_to_iso8601(char *buf, int buf_size, int64_t value)
 441 {
 442     time_t t = 631112400LL + 86400*av_int2double(value);
 443     struct tm *tm = gmtime(&t);
 444     if (tm)
 445         strftime(buf, buf_size, "%Y-%m-%d %H:%M:%S", gmtime(&t));
 446     else
 447         buf[0] = '\0';
 448 }
 449
 450 static void get_attachment(AVFormatContext *s, AVIOContext *pb, int length)
 451 {
 452     char mime[1024];
 453     char description[1024];
 454     unsigned int filesize;
 455     AVStream *st;
 456     int64_t pos = avio_tell(pb);
 457
 458     avio_get_str16le(pb, INT_MAX, mime, sizeof(mime));
 459     if (strcmp(mime, "image/jpeg"))
 460         goto done;
 461
 462     avio_r8(pb);
 463     avio_get_str16le(pb, INT_MAX, description, sizeof(description));
 464     filesize = avio_rl32(pb);
 465     if (!filesize)
 466         goto done;
 467
 468     st = avformat_new_stream(s, NULL);
 469     if (!st)
 470         goto done;
 471     av_dict_set(&st->metadata, "title", description, 0);
 472     st->codec->codec_id   = AV_CODEC_ID_MJPEG;
 473     st->codec->codec_type = AVMEDIA_TYPE_ATTACHMENT;
 474     st->codec->extradata  = av_mallocz(filesize);
 475     st->id = -1;
 476     if (!st->codec->extradata)
 477         goto done;
 478     st->codec->extradata_size = filesize;
 479     avio_read(pb, st->codec->extradata, filesize);
 480 done:
 481     avio_seek(pb, pos + length, SEEK_SET);
 482 }
 483
 484 static void get_tag(AVFormatContext *s, AVIOContext *pb, const char *key, int type, int length)
 485 {
 486     int buf_size = FFMAX(2*length, LEN_PRETTY_GUID) + 1;
 487     char *buf = av_malloc(buf_size);
 488     if (!buf)
 489         return;
 490
 491     if (type == 0 && length == 4) {
 492         snprintf(buf, buf_size, "%"PRIi32, avio_rl32(pb));
 493     } else if (type == 1) {
 494         avio_get_str16le(pb, length, buf, buf_size);
 495         if (!strlen(buf)) {
 496            av_free(buf);
 497            return;
 498         }
 499     } else if (type == 3 && length == 4) {
 500         strcpy(buf, avio_rl32(pb) ? "true" : "false");
 501     } else if (type == 4 && length == 8) {
 502         int64_t num = avio_rl64(pb);
 503         if (!strcmp(key, "WM/EncodingTime") ||
 504             !strcmp(key, "WM/MediaOriginalBroadcastDateTime"))
 505             filetime_to_iso8601(buf, buf_size, num);
 506         else if (!strcmp(key, "WM/WMRVEncodeTime") ||
 507                  !strcmp(key, "WM/WMRVEndTime"))
 508             crazytime_to_iso8601(buf, buf_size, num);
 509         else if (!strcmp(key, "WM/WMRVExpirationDate"))
 510             oledate_to_iso8601(buf, buf_size, num);
 511         else if (!strcmp(key, "WM/WMRVBitrate"))
 512             snprintf(buf, buf_size, "%f", av_int2double(num));
 513         else
 514             snprintf(buf, buf_size, "%"PRIi64, num);
 515     } else if (type == 5 && length == 2) {
 516         snprintf(buf, buf_size, "%"PRIi16, avio_rl16(pb));
 517     } else if (type == 6 && length == 16) {
 518         ff_asf_guid guid;
 519         avio_read(pb, guid, 16);
 520         snprintf(buf, buf_size, PRI_PRETTY_GUID, ARG_PRETTY_GUID(guid));
 521     } else if (type == 2 && !strcmp(key, "WM/Picture")) {
 522         get_attachment(s, pb, length);
 523         av_freep(&buf);
 524         return;
 525     } else {
 526         av_freep(&buf);
 527         av_log(s, AV_LOG_WARNING, "unsupported metadata entry; key:%s, type:%d, length:0x%x\n", key, type, length);
 528         avio_skip(pb, length);
 529         return;
 530     }
 531
 532     av_dict_set(&s->metadata, key, buf, 0);
 533     av_freep(&buf);
 534 }
 535
 536 /**
 537  * Parse metadata entries
 538  */
 539 static void parse_legacy_attrib(AVFormatContext *s, AVIOContext *pb)
 540 {
 541     ff_asf_guid guid;
 542     int length, type;
 543     while(!pb->eof_reached) {
 544         char key[1024];
 545         ff_get_guid(pb, &guid);
 546         type   = avio_rl32(pb);
 547         length = avio_rl32(pb);
 548         if (!length)
 549             break;
 550         if (ff_guidcmp(&guid, metadata_guid)) {
 551             av_log(s, AV_LOG_WARNING, "unknown guid "FF_PRI_GUID", expected metadata_guid; "
 552                    "remaining metadata entries ignored\n", FF_ARG_GUID(guid));
 553             break;
 554         }
 555         avio_get_str16le(pb, INT_MAX, key, sizeof(key));
 556         get_tag(s, pb, key, type, length);
 557     }
 558
 559     ff_metadata_conv(&s->metadata, NULL, ff_asf_metadata_conv);
 560 }
 561
 562 /**
 563  * parse VIDEOINFOHEADER2 structure
 564  * @return bytes consumed
 565  */
 566 static int parse_videoinfoheader2(AVFormatContext *s, AVStream *st)
 567 {
 568     WtvContext *wtv = s->priv_data;
 569     AVIOContext *pb = wtv->pb;
 570
 571     avio_skip(pb, 72);  // picture aspect ratio is unreliable
 572     ff_get_bmp_header(pb, st);
 573
 574     return 72 + 40;
 575 }
 576
 577 /**
 578  * Parse MPEG1WAVEFORMATEX extradata structure
 579  */
 580 static void parse_mpeg1waveformatex(AVStream *st)
 581 {
 582     /* fwHeadLayer */
 583     switch (AV_RL16(st->codec->extradata)) {
 584     case 0x0001 : st->codec->codec_id = AV_CODEC_ID_MP1; break;
 585     case 0x0002 : st->codec->codec_id = AV_CODEC_ID_MP2; break;
 586     case 0x0004 : st->codec->codec_id = AV_CODEC_ID_MP3; break;
 587     }
 588
 589     st->codec->bit_rate = AV_RL32(st->codec->extradata + 2); /* dwHeadBitrate */
 590
 591     /* dwHeadMode */
 592     switch (AV_RL16(st->codec->extradata + 6)) {
 593     case 1 :
 594     case 2 :
 595     case 4 : st->codec->channels       = 2;
 596              st->codec->channel_layout = AV_CH_LAYOUT_STEREO;
 597              break;
 598     case 8 : st->codec->channels       = 1;
 599              st->codec->channel_layout = AV_CH_LAYOUT_MONO;
 600              break;
 601     }
 602 }
 603
 604 /**
 605  * Initialise stream
 606  * @param st Stream to initialise, or NULL to create and initialise new stream
 607  * @return NULL on error
 608  */
 609 static AVStream * new_stream(AVFormatContext *s, AVStream *st, int sid, int codec_type)
 610 {
 611     if (st) {
 612         if (st->codec->extradata) {
 613             av_freep(&st->codec->extradata);
 614             st->codec->extradata_size = 0;
 615         }
 616     } else {
 617         WtvStream *wst = av_mallocz(sizeof(WtvStream));
 618         if (!wst)
 619             return NULL;
 620         st = avformat_new_stream(s, NULL);
 621         if (!st)
 622             return NULL;
 623         st->id = sid;
 624         st->priv_data = wst;
 625     }
 626     st->codec->codec_type = codec_type;
 627     st->need_parsing      = AVSTREAM_PARSE_FULL;
 628     avpriv_set_pts_info(st, 64, 1, 10000000);
 629     return st;
 630 }
 631
 632 /**
 633  * parse Media Type structure and populate stream
 634  * @param st         Stream, or NULL to create new stream
 635  * @param mediatype  Mediatype GUID
 636  * @param subtype    Subtype GUID
 637  * @param formattype Format GUID
 638  * @param size       Size of format buffer
 639  * @return NULL on error
 640  */
 641 static AVStream * parse_media_type(AVFormatContext *s, AVStream *st, int sid,
 642                                    ff_asf_guid mediatype, ff_asf_guid subtype,
 643                                    ff_asf_guid formattype, int size)
 644 {
 645     WtvContext *wtv = s->priv_data;
 646     AVIOContext *pb = wtv->pb;
 647     if (!ff_guidcmp(subtype, mediasubtype_cpfilters_processed) &&
 648         !ff_guidcmp(formattype, format_cpfilters_processed)) {
 649         ff_asf_guid actual_subtype;
 650         ff_asf_guid actual_formattype;
 651
 652         if (size < 32) {
 653             av_log(s, AV_LOG_WARNING, "format buffer size underflow\n");
 654             avio_skip(pb, size);
 655             return NULL;
 656         }
 657
 658         avio_skip(pb, size - 32);
 659         ff_get_guid(pb, &actual_subtype);
 660         ff_get_guid(pb, &actual_formattype);
 661         avio_seek(pb, -size, SEEK_CUR);
 662
 663         st = parse_media_type(s, st, sid, mediatype, actual_subtype, actual_formattype, size - 32);
 664         avio_skip(pb, 32);
 665         return st;
 666     } else if (!ff_guidcmp(mediatype, mediatype_audio)) {
 667         st = new_stream(s, st, sid, AVMEDIA_TYPE_AUDIO);
 668         if (!st)
 669             return NULL;
 670         if (!ff_guidcmp(formattype, format_waveformatex)) {
 671             int ret = ff_get_wav_header(pb, st->codec, size);
 672             if (ret < 0)
 673                 return NULL;
 674         } else {
 675             if (ff_guidcmp(formattype, format_none))
 676                 av_log(s, AV_LOG_WARNING, "unknown formattype:"FF_PRI_GUID"\n", FF_ARG_GUID(formattype));
 677             avio_skip(pb, size);
 678         }
 679
 680         if (!memcmp(subtype + 4, (const uint8_t[]){FF_MEDIASUBTYPE_BASE_GUID}, 12)) {
 681             st->codec->codec_id = ff_wav_codec_get_id(AV_RL32(subtype), st->codec->bits_per_coded_sample);
 682         } else if (!ff_guidcmp(subtype, mediasubtype_mpeg1payload)) {
 683             if (st->codec->extradata && st->codec->extradata_size >= 22)
 684                 parse_mpeg1waveformatex(st);
 685             else
 686                 av_log(s, AV_LOG_WARNING, "MPEG1WAVEFORMATEX underflow\n");
 687         } else {
 688             st->codec->codec_id = ff_codec_guid_get_id(ff_codec_wav_guids, subtype);
 689             if (st->codec->codec_id == AV_CODEC_ID_NONE)
 690                 av_log(s, AV_LOG_WARNING, "unknown subtype:"FF_PRI_GUID"\n", FF_ARG_GUID(subtype));
 691         }
 692         return st;
 693     } else if (!ff_guidcmp(mediatype, mediatype_video)) {
 694         st = new_stream(s, st, sid, AVMEDIA_TYPE_VIDEO);
 695         if (!st)
 696             return NULL;
 697         if (!ff_guidcmp(formattype, format_videoinfo2)) {
 698             int consumed = parse_videoinfoheader2(s, st);
 699             avio_skip(pb, FFMAX(size - consumed, 0));
 700         } else if (!ff_guidcmp(formattype, format_mpeg2_video)) {
 701             int consumed = parse_videoinfoheader2(s, st);
 702             avio_skip(pb, FFMAX(size - consumed, 0));
 703         } else {
 704             if (ff_guidcmp(formattype, format_none))
 705                 av_log(s, AV_LOG_WARNING, "unknown formattype:"FF_PRI_GUID"\n", FF_ARG_GUID(formattype));
 706             avio_skip(pb, size);
 707         }
 708
 709         if (!memcmp(subtype + 4, (const uint8_t[]){FF_MEDIASUBTYPE_BASE_GUID}, 12)) {
 710             st->codec->codec_id = ff_codec_get_id(ff_codec_bmp_tags, AV_RL32(subtype));
 711         } else {
 712             st->codec->codec_id = ff_codec_guid_get_id(video_guids, subtype);
 713         }
 714         if (st->codec->codec_id == AV_CODEC_ID_NONE)
 715             av_log(s, AV_LOG_WARNING, "unknown subtype:"FF_PRI_GUID"\n", FF_ARG_GUID(subtype));
 716         return st;
 717     } else if (!ff_guidcmp(mediatype, mediatype_mpeg2_pes) &&
 718                !ff_guidcmp(subtype, mediasubtype_dvb_subtitle)) {
 719         st = new_stream(s, st, sid, AVMEDIA_TYPE_SUBTITLE);
 720         if (!st)
 721             return NULL;
 722         if (ff_guidcmp(formattype, format_none))
 723             av_log(s, AV_LOG_WARNING, "unknown formattype:"FF_PRI_GUID"\n", FF_ARG_GUID(formattype));
 724         avio_skip(pb, size);
 725         st->codec->codec_id = AV_CODEC_ID_DVB_SUBTITLE;
 726         return st;
 727     } else if (!ff_guidcmp(mediatype, mediatype_mstvcaption) &&
 728                (!ff_guidcmp(subtype, mediasubtype_teletext) || !ff_guidcmp(subtype, mediasubtype_dtvccdata))) {
 729         st = new_stream(s, st, sid, AVMEDIA_TYPE_SUBTITLE);
 730         if (!st)
 731             return NULL;
 732         if (ff_guidcmp(formattype, format_none))
 733             av_log(s, AV_LOG_WARNING, "unknown formattype:"FF_PRI_GUID"\n", FF_ARG_GUID(formattype));
 734         avio_skip(pb, size);
 735         st->codec->codec_id   = AV_CODEC_ID_DVB_TELETEXT;
 736         return st;
 737     } else if (!ff_guidcmp(mediatype, mediatype_mpeg2_sections) &&
 738                !ff_guidcmp(subtype, mediasubtype_mpeg2_sections)) {
 739         if (ff_guidcmp(formattype, format_none))
 740             av_log(s, AV_LOG_WARNING, "unknown formattype:"FF_PRI_GUID"\n", FF_ARG_GUID(formattype));
 741         avio_skip(pb, size);
 742         return NULL;
 743     }
 744
 745     av_log(s, AV_LOG_WARNING, "unknown media type, mediatype:"FF_PRI_GUID
 746                               ", subtype:"FF_PRI_GUID", formattype:"FF_PRI_GUID"\n",
 747                               FF_ARG_GUID(mediatype), FF_ARG_GUID(subtype), FF_ARG_GUID(formattype));
 748     avio_skip(pb, size);
 749     return NULL;
 750 }
 751
 752 enum {
 753     SEEK_TO_DATA = 0,
 754     SEEK_TO_PTS,
 755 };
 756
 757 /**
 758  * Parse WTV chunks
 759  * @param mode SEEK_TO_DATA or SEEK_TO_PTS
 760  * @param seekts timestamp
 761  * @param[out] len_ptr Length of data chunk
 762  * @return stream index of data chunk, or <0 on error
 763  */
 764 static int parse_chunks(AVFormatContext *s, int mode, int64_t seekts, int *len_ptr)
 765 {
 766     WtvContext *wtv = s->priv_data;
 767     AVIOContext *pb = wtv->pb;
 768     while (!pb->eof_reached) {
 769         ff_asf_guid g;
 770         int len, sid, consumed;
 771
 772         ff_get_guid(pb, &g);
 773         len = avio_rl32(pb);
 774         if (len < 32)
 775             break;
 776         sid = avio_rl32(pb) & 0x7FFF;
 777         avio_skip(pb, 8);
 778         consumed = 32;
 779
 780         if (!ff_guidcmp(g, stream_guid)) {
 781             if (ff_find_stream_index(s, sid) < 0) {
 782                 ff_asf_guid mediatype, subtype, formattype;
 783                 int size;
 784                 avio_skip(pb, 28);
 785                 ff_get_guid(pb, &mediatype);
 786                 ff_get_guid(pb, &subtype);
 787                 avio_skip(pb, 12);
 788                 ff_get_guid(pb, &formattype);
 789                 size = avio_rl32(pb);
 790                 parse_media_type(s, 0, sid, mediatype, subtype, formattype, size);
 791                 consumed += 92 + size;
 792             }
 793         } else if (!ff_guidcmp(g, stream2_guid)) {
 794             int stream_index = ff_find_stream_index(s, sid);
 795             if (stream_index >= 0 && !((WtvStream*)s->streams[stream_index]->priv_data)->seen_data) {
 796                 ff_asf_guid mediatype, subtype, formattype;
 797                 int size;
 798                 avio_skip(pb, 12);
 799                 ff_get_guid(pb, &mediatype);
 800                 ff_get_guid(pb, &subtype);
 801                 avio_skip(pb, 12);
 802                 ff_get_guid(pb, &formattype);
 803                 size = avio_rl32(pb);
 804                 parse_media_type(s, s->streams[stream_index], sid, mediatype, subtype, formattype, size);
 805                 consumed += 76 + size;
 806             }
 807         } else if (!ff_guidcmp(g, EVENTID_AudioDescriptorSpanningEvent) ||
 808                    !ff_guidcmp(g, EVENTID_CtxADescriptorSpanningEvent) ||
 809                    !ff_guidcmp(g, EVENTID_CSDescriptorSpanningEvent) ||
 810                    !ff_guidcmp(g, EVENTID_StreamIDSpanningEvent) ||
 811                    !ff_guidcmp(g, EVENTID_SubtitleSpanningEvent) ||
 812                    !ff_guidcmp(g, EVENTID_TeletextSpanningEvent)) {
 813             int stream_index = ff_find_stream_index(s, sid);
 814             if (stream_index >= 0) {
 815                 AVStream *st = s->streams[stream_index];
 816                 uint8_t buf[258];
 817                 const uint8_t *pbuf = buf;
 818                 int buf_size;
 819
 820                 avio_skip(pb, 8);
 821                 consumed += 8;
 822                 if (!ff_guidcmp(g, EVENTID_CtxADescriptorSpanningEvent) ||
 823                     !ff_guidcmp(g, EVENTID_CSDescriptorSpanningEvent)) {
 824                     avio_skip(pb, 6);
 825                     consumed += 6;
 826                 }
 827
 828                 buf_size = FFMIN(len - consumed, sizeof(buf));
 829                 avio_read(pb, buf, buf_size);
 830                 consumed += buf_size;
 831                 ff_parse_mpeg2_descriptor(s, st, 0, &pbuf, buf + buf_size, NULL, 0, 0, NULL);
 832             }
 833         } else if (!ff_guidcmp(g, EVENTID_AudioTypeSpanningEvent)) {
 834             int stream_index = ff_find_stream_index(s, sid);
 835             if (stream_index >= 0) {
 836                 AVStream *st = s->streams[stream_index];
 837                 int audio_type;
 838                 avio_skip(pb, 8);
 839                 audio_type = avio_r8(pb);
 840                 if (audio_type == 2)
 841                     st->disposition |= AV_DISPOSITION_HEARING_IMPAIRED;
 842                 else if (audio_type == 3)
 843                     st->disposition |= AV_DISPOSITION_VISUAL_IMPAIRED;
 844                 consumed += 9;
 845             }
 846         } else if (!ff_guidcmp(g, EVENTID_DVBScramblingControlSpanningEvent)) {
 847             int stream_index = ff_find_stream_index(s, sid);
 848             if (stream_index >= 0) {
 849                 avio_skip(pb, 12);
 850                 if (avio_rl32(pb))
 851                     av_log(s, AV_LOG_WARNING, "DVB scrambled stream detected (st:%d), decoding will likely fail\n", stream_index);
 852                 consumed += 16;
 853             }
 854         } else if (!ff_guidcmp(g, EVENTID_LanguageSpanningEvent)) {
 855             int stream_index = ff_find_stream_index(s, sid);
 856             if (stream_index >= 0) {
 857                 AVStream *st = s->streams[stream_index];
 858                 uint8_t language[4];
 859                 avio_skip(pb, 12);
 860                 avio_read(pb, language, 3);
 861                 if (language[0]) {
 862                     language[3] = 0;
 863                     av_dict_set(&st->metadata, "language", language, 0);
 864                     if (!strcmp(language, "nar") || !strcmp(language, "NAR"))
 865                         st->disposition |= AV_DISPOSITION_VISUAL_IMPAIRED;
 866                 }
 867                 consumed += 15;
 868             }
 869         } else if (!ff_guidcmp(g, timestamp_guid)) {
 870             int stream_index = ff_find_stream_index(s, sid);
 871             if (stream_index >= 0) {
 872                 avio_skip(pb, 8);
 873                 wtv->pts = avio_rl64(pb);
 874                 consumed += 16;
 875                 if (wtv->pts == -1)
 876                     wtv->pts = AV_NOPTS_VALUE;
 877                 else {
 878                     wtv->last_valid_pts = wtv->pts;
 879                     if (wtv->epoch == AV_NOPTS_VALUE || wtv->pts < wtv->epoch)
 880                         wtv->epoch = wtv->pts;
 881                 if (mode == SEEK_TO_PTS && wtv->pts >= seekts) {
 882 #define WTV_PAD8(x) (((x) + 7) & ~7)
 883                     avio_skip(pb, WTV_PAD8(len) - consumed);
 884                     return 0;
 885                 }
 886                 }
 887             }
 888         } else if (!ff_guidcmp(g, data_guid)) {
 889             int stream_index = ff_find_stream_index(s, sid);
 890             if (mode == SEEK_TO_DATA && stream_index >= 0 && len > 32) {
 891                 WtvStream *wst = s->streams[stream_index]->priv_data;
 892                 wst->seen_data = 1;
 893                 if (len_ptr) {
 894                     *len_ptr = len;
 895                 }
 896                 return stream_index;
 897             }
 898         } else if (
 899             !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}) ||
 900             !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}) ||
 901             !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}) ||
 902             !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}) ||
 903             !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}) ||
 904             !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}) ||
 905             !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}) ||
 906             !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}) ||
 907             !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}) ||
 908             !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}) ||
 909             !ff_guidcmp(g, (const ff_asf_guid){0x1E,0xBE,0xC3,0xC5,0x43,0x92,0xDC,0x11,0x85,0xE5,0x00,0x12,0x3F,0x6F,0x73,0xB9}) ||
 910             !ff_guidcmp(g, (const ff_asf_guid){0x3B,0x86,0xA2,0xB1,0xEB,0x1E,0xC3,0x44,0x8C,0x88,0x1C,0xA3,0xFF,0xE3,0xE7,0x6A}) ||
 911             !ff_guidcmp(g, (const ff_asf_guid){0x4E,0x7F,0x4C,0x5B,0xC4,0xD0,0x38,0x4B,0xA8,0x3E,0x21,0x7F,0x7B,0xBF,0x52,0xE7}) ||
 912             !ff_guidcmp(g, (const ff_asf_guid){0x63,0x36,0xEB,0xFE,0xA1,0x7E,0xD9,0x11,0x83,0x08,0x00,0x07,0xE9,0x5E,0xAD,0x8D}) ||
 913             !ff_guidcmp(g, (const ff_asf_guid){0x70,0xE9,0xF1,0xF8,0x89,0xA4,0x4C,0x4D,0x83,0x73,0xB8,0x12,0xE0,0xD5,0xF8,0x1E}) ||
 914             !ff_guidcmp(g, (const ff_asf_guid){0x96,0xC3,0xD2,0xC2,0x7E,0x9A,0xDA,0x11,0x8B,0xF7,0x00,0x07,0xE9,0x5E,0xAD,0x8D}) ||
 915             !ff_guidcmp(g, (const ff_asf_guid){0x97,0xC3,0xD2,0xC2,0x7E,0x9A,0xDA,0x11,0x8B,0xF7,0x00,0x07,0xE9,0x5E,0xAD,0x8D}) ||
 916             !ff_guidcmp(g, (const ff_asf_guid){0xA1,0xC3,0xD2,0xC2,0x7E,0x9A,0xDA,0x11,0x8B,0xF7,0x00,0x07,0xE9,0x5E,0xAD,0x8D})) {
 917             //ignore known guids
 918         } else
 919             av_log(s, AV_LOG_WARNING, "unsupported chunk:"FF_PRI_GUID"\n", FF_ARG_GUID(g));
 920
 921         avio_skip(pb, WTV_PAD8(len) - consumed);
 922     }
 923     return AVERROR_EOF;
 924 }
 925
 926 /* declare utf16le strings */
 927 #define _ , 0,
 928 static const uint8_t timeline_le16[] =
 929     {'t'_'i'_'m'_'e'_'l'_'i'_'n'_'e', 0};
 930 static const uint8_t table_0_entries_legacy_attrib_le16[] =
 931     {'t'_'a'_'b'_'l'_'e'_'.'_'0'_'.'_'e'_'n'_'t'_'r'_'i'_'e'_'s'_'.'_'l'_'e'_'g'_'a'_'c'_'y'_'_'_'a'_'t'_'t'_'r'_'i'_'b', 0};
 932 static const uint8_t table_0_entries_time_le16[] =
 933     {'t'_'a'_'b'_'l'_'e'_'.'_'0'_'.'_'e'_'n'_'t'_'r'_'i'_'e'_'s'_'.'_'t'_'i'_'m'_'e', 0};
 934 static const uint8_t timeline_table_0_entries_Events_le16[] =
 935     {'t'_'i'_'m'_'e'_'l'_'i'_'n'_'e'_'.'_'t'_'a'_'b'_'l'_'e'_'.'_'0'_'.'_'e'_'n'_'t'_'r'_'i'_'e'_'s'_'.'_'E'_'v'_'e'_'n'_'t'_'s', 0};
 936 #undef _
 937
 938 static int read_header(AVFormatContext *s)
 939 {
 940     WtvContext *wtv = s->priv_data;
 941     int root_sector, root_size;
 942     uint8_t root[WTV_SECTOR_SIZE];
 943     AVIOContext *pb;
 944     int64_t timeline_pos;
 945     int ret;
 946
 947     wtv->epoch          =
 948     wtv->pts            =
 949     wtv->last_valid_pts = AV_NOPTS_VALUE;
 950
 951     /* read root directory sector */
 952     avio_skip(s->pb, 0x30);
 953     root_size = avio_rl32(s->pb);
 954     if (root_size > sizeof(root)) {
 955         av_log(s, AV_LOG_ERROR, "root directory size exceeds sector size\n");
 956         return AVERROR_INVALIDDATA;
 957     }
 958     avio_skip(s->pb, 4);
 959     root_sector = avio_rl32(s->pb);
 960
 961     avio_seek(s->pb, root_sector << WTV_SECTOR_BITS, SEEK_SET);
 962     root_size = avio_read(s->pb, root, root_size);
 963     if (root_size < 0)
 964         return AVERROR_INVALIDDATA;
 965
 966     /* parse chunks up until first data chunk */
 967     wtv->pb = wtvfile_open(s, root, root_size, timeline_le16);
 968     if (!wtv->pb) {
 969         av_log(s, AV_LOG_ERROR, "timeline data missing\n");
 970         return AVERROR_INVALIDDATA;
 971     }
 972
 973     ret = parse_chunks(s, SEEK_TO_DATA, 0, 0);
 974     if (ret < 0)
 975         return ret;
 976     avio_seek(wtv->pb, -32, SEEK_CUR);
 977
 978     timeline_pos = avio_tell(s->pb); // save before opening another file
 979
 980     /* read metadata */
 981     pb = wtvfile_open(s, root, root_size, table_0_entries_legacy_attrib_le16);
 982     if (pb) {
 983         parse_legacy_attrib(s, pb);
 984         wtvfile_close(pb);
 985     }
 986
 987     /* read seek index */
 988     if (s->nb_streams) {
 989         AVStream *st = s->streams[0];
 990         pb = wtvfile_open(s, root, root_size, table_0_entries_time_le16);
 991         if (pb) {
 992             while(1) {
 993                 uint64_t timestamp = avio_rl64(pb);
 994                 uint64_t frame_nb  = avio_rl64(pb);
 995                 if (pb->eof_reached)
 996                     break;
 997                 ff_add_index_entry(&wtv->index_entries, &wtv->nb_index_entries, &wtv->index_entries_allocated_size,
 998                                    0, timestamp, frame_nb, 0, AVINDEX_KEYFRAME);
 999             }
1000             wtvfile_close(pb);
1001
1002             if (wtv->nb_index_entries) {
1003                 pb = wtvfile_open(s, root, root_size, timeline_table_0_entries_Events_le16);
1004                 if (pb) {
1005                     int i;
1006                     while (1) {
1007                         uint64_t frame_nb = avio_rl64(pb);
1008                         uint64_t position = avio_rl64(pb);
1009                         if (pb->eof_reached)
1010                             break;
1011                         for (i = wtv->nb_index_entries - 1; i >= 0; i--) {
1012                             AVIndexEntry *e = wtv->index_entries + i;
1013                             if (frame_nb > e->size)
1014                                 break;
1015                             if (position > e->pos)
1016                                 e->pos = position;
1017                         }
1018                     }
1019                     wtvfile_close(pb);
1020                     st->duration = wtv->index_entries[wtv->nb_index_entries - 1].timestamp;
1021                 }
1022             }
1023         }
1024     }
1025
1026     avio_seek(s->pb, timeline_pos, SEEK_SET);
1027     return 0;
1028 }
1029
1030 static int read_packet(AVFormatContext *s, AVPacket *pkt)
1031 {
1032     WtvContext *wtv = s->priv_data;
1033     AVIOContext *pb = wtv->pb;
1034     int stream_index, len, ret;
1035
1036     stream_index = parse_chunks(s, SEEK_TO_DATA, 0, &len);
1037     if (stream_index < 0)
1038         return stream_index;
1039
1040     ret = av_get_packet(pb, pkt, len - 32);
1041     if (ret < 0)
1042         return ret;
1043     pkt->stream_index = stream_index;
1044     pkt->pts          = wtv->pts;
1045     avio_skip(pb, WTV_PAD8(len) - len);
1046     return 0;
1047 }
1048
1049 static int read_seek(AVFormatContext *s, int stream_index,
1050                      int64_t ts, int flags)
1051 {
1052     WtvContext *wtv = s->priv_data;
1053     AVIOContext *pb = wtv->pb;
1054     AVStream *st = s->streams[0];
1055     int64_t ts_relative;
1056     int i;
1057
1058     if ((flags & AVSEEK_FLAG_FRAME) || (flags & AVSEEK_FLAG_BYTE))
1059         return AVERROR(ENOSYS);
1060
1061     /* timestamp adjustment is required because wtv->pts values are absolute,
1062      * whereas AVIndexEntry->timestamp values are relative to epoch. */
1063     ts_relative = ts;
1064     if (wtv->epoch != AV_NOPTS_VALUE)
1065         ts_relative -= wtv->epoch;
1066
1067     i = ff_index_search_timestamp(wtv->index_entries, wtv->nb_index_entries, ts_relative, flags);
1068     if (i < 0) {
1069         if (wtv->last_valid_pts == AV_NOPTS_VALUE || ts < wtv->last_valid_pts)
1070             avio_seek(pb, 0, SEEK_SET);
1071         else if (st->duration != AV_NOPTS_VALUE && ts_relative > st->duration && wtv->nb_index_entries)
1072             avio_seek(pb, wtv->index_entries[wtv->nb_index_entries - 1].pos, SEEK_SET);
1073         if (parse_chunks(s, SEEK_TO_PTS, ts, 0) < 0)
1074             return AVERROR(ERANGE);
1075         return 0;
1076     }
1077     wtv->pts = wtv->index_entries[i].timestamp;
1078     if (wtv->epoch != AV_NOPTS_VALUE)
1079         wtv->pts += wtv->epoch;
1080     wtv->last_valid_pts = wtv->pts;
1081     avio_seek(pb, wtv->index_entries[i].pos, SEEK_SET);
1082     return 0;
1083 }
1084
1085 static int read_close(AVFormatContext *s)
1086 {
1087     WtvContext *wtv = s->priv_data;
1088     av_free(wtv->index_entries);
1089     wtvfile_close(wtv->pb);
1090     return 0;
1091 }
1092
1093 AVInputFormat ff_wtv_demuxer = {
1094     .name           = "wtv",
1095     .long_name      = NULL_IF_CONFIG_SMALL("Windows Television (WTV)"),
1096     .priv_data_size = sizeof(WtvContext),
1097     .read_probe     = read_probe,
1098     .read_header    = read_header,
1099     .read_packet    = read_packet,
1100     .read_seek      = read_seek,
1101     .read_close     = read_close,
1102     .flags          = AVFMT_SHOW_IDS,
1103 };