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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 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 "libavutil/intfloat_readwrite.h"
  30 #include "avformat.h"
  31 #include "riff.h"
  32 #include "asf.h"
  33 #include "mpegts.h"
  34
  35 /* Macros for formating GUIDs */
  36 #define PRI_GUID \
  37     "%02x%02x%02x%02x%02x%02x%02x%02x%02x%02x%02x%02x%02x%02x%02x%02x"
  38 #define ARG_GUID(g) \
  39     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]
  40
  41 #define PRI_PRETTY_GUID \
  42     "%08x-%04x-%04x-%02x%02x%02x%02x%02x%02x%02x%02x"
  43 #define ARG_PRETTY_GUID(g) \
  44     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]
  45 #define LEN_PRETTY_GUID 34
  46
  47 /*
  48  *
  49  * File system routines
  50  *
  51  */
  52
  53 #define WTV_SECTOR_BITS    12
  54 #define WTV_SECTOR_SIZE    (1 << WTV_SECTOR_BITS)
  55 #define WTV_BIGSECTOR_BITS 18
  56
  57 typedef struct {
  58     ByteIOContext *pb_filesystem;  /** file system (AVFormatContext->pb) */
  59
  60     int sector_bits;     /** sector shift bits; used to convert sector number into pb_filesystem offset */
  61     uint32_t *sectors;   /** file allocation table */
  62     int nb_sectors;      /** number of sectors */
  63
  64     int error;
  65     int64_t position;
  66     int64_t length;
  67 } WtvFile;
  68
  69 /**
  70  * @return bytes read, 0 on end of file, or <0 on error
  71  */
  72 static int wtvfile_read_packet(void *opaque, uint8_t *buf, int buf_size)
  73 {
  74     WtvFile *wf = opaque;
  75     ByteIOContext *pb = wf->pb_filesystem;
  76     int nread = 0;
  77
  78     if (wf->error || url_ferror(pb))
  79         return -1;
  80     if (wf->position >= wf->length || url_feof(pb))
  81         return 0;
  82
  83     buf_size = FFMIN(buf_size, wf->length - wf->position);
  84     while(nread < buf_size) {
  85         int n;
  86         int remaining_in_sector = (1 << wf->sector_bits) - (wf->position & ((1 << wf->sector_bits) - 1));
  87         int read_request        = FFMIN(buf_size - nread, remaining_in_sector);
  88
  89         n = get_buffer(pb, buf, read_request);
  90         if (n <= 0)
  91             break;
  92         nread += n;
  93         buf += n;
  94         wf->position += n;
  95         if (n == remaining_in_sector) {
  96             int i = wf->position >> wf->sector_bits;
  97             if (i >= wf->nb_sectors ||
  98                 (wf->sectors[i] != wf->sectors[i - 1] + (1 << (wf->sector_bits - WTV_SECTOR_BITS)) &&
  99                 url_fseek(pb, (int64_t)wf->sectors[i] << WTV_SECTOR_BITS, SEEK_SET) < 0)) {
 100                 wf->error = 1;
 101                 break;
 102             }
 103         }
 104     }
 105     return nread;
 106 }
 107
 108 /**
 109  * @return position (or file length)
 110  */
 111 static int64_t wtvfile_seek(void *opaque, int64_t offset, int whence)
 112 {
 113     WtvFile *wf = opaque;
 114     ByteIOContext *pb = wf->pb_filesystem;
 115
 116     if (whence == AVSEEK_SIZE)
 117         return wf->length;
 118     else if (whence == SEEK_CUR)
 119         offset = wf->position + offset;
 120     else if (whence == SEEK_END)
 121         offset = wf->length;
 122
 123     wf->error = offset < 0 || offset >= wf->length ||
 124                 url_fseek(pb, ((int64_t)wf->sectors[offset >> wf->sector_bits] << WTV_SECTOR_BITS)
 125                               + (offset & ((1 << wf->sector_bits) - 1)), SEEK_SET) < 0;
 126     wf->position = offset;
 127     return offset;
 128 }
 129
 130 /**
 131  * read non-zero integers (le32) from input stream
 132  * @param pb
 133  * @param[out] data destination
 134  * @param     count maximum number of integers to read
 135  * @return    total number of integers read
 136  */
 137 static int read_ints(ByteIOContext *pb, uint32_t *data, int count)
 138 {
 139     int i, total = 0;
 140     for (i = 0; i < count; i++) {
 141         if ((data[total] = get_le32(pb)))
 142            total++;
 143     }
 144     return total;
 145 }
 146
 147 /**
 148  * Open file
 149  * @param first_sector  First sector
 150  * @param length        Length of file (bytes)
 151  * @param depth         File allocation table depth
 152  * @return NULL on error
 153  */
 154 static ByteIOContext * wtvfile_open_sector(int first_sector, uint64_t length, int depth, AVFormatContext *s)
 155 {
 156     ByteIOContext *pb;
 157     WtvFile *wf;
 158     uint8_t *buffer;
 159
 160     if (url_fseek(s->pb, first_sector << WTV_SECTOR_BITS, SEEK_SET) < 0)
 161         return NULL;
 162
 163     wf = av_mallocz(sizeof(WtvFile));
 164     if (!wf)
 165         return NULL;
 166
 167     if (depth == 0) {
 168         wf->sectors = av_malloc(sizeof(uint32_t));
 169         if (!wf->sectors) {
 170             av_free(wf);
 171             return NULL;
 172         }
 173         wf->sectors[0]  = first_sector;
 174         wf->nb_sectors  = 1;
 175         wf->sector_bits = WTV_SECTOR_BITS;
 176     } else if (depth == 1) {
 177         wf->sectors = av_malloc(WTV_SECTOR_SIZE);
 178         if (!wf->sectors) {
 179             av_free(wf);
 180             return NULL;
 181         }
 182         wf->nb_sectors  = read_ints(s->pb, wf->sectors, WTV_SECTOR_SIZE / 4);
 183         wf->sector_bits = length & (1ULL<<63) ? WTV_SECTOR_BITS : WTV_BIGSECTOR_BITS;
 184     } else if (depth == 2) {
 185         uint32_t sectors1[WTV_SECTOR_SIZE / 4];
 186         int nb_sectors1 = read_ints(s->pb, sectors1, WTV_SECTOR_SIZE / 4);
 187         int i;
 188
 189         wf->sectors = av_malloc(nb_sectors1 << WTV_SECTOR_BITS);
 190         if (!wf->sectors) {
 191             av_free(wf);
 192             return NULL;
 193         }
 194         wf->nb_sectors = 0;
 195         for (i = 0; i < nb_sectors1; i++) {
 196             if (url_fseek(s->pb, (int64_t)sectors1[i] << WTV_SECTOR_BITS, SEEK_SET) < 0)
 197                 break;
 198             wf->nb_sectors += read_ints(s->pb, wf->sectors + i * WTV_SECTOR_SIZE / 4, WTV_SECTOR_SIZE / 4);
 199         }
 200         wf->sector_bits = length & (1ULL<<63) ? WTV_SECTOR_BITS : WTV_BIGSECTOR_BITS;
 201     } else {
 202         av_log(s, AV_LOG_ERROR, "unsupported file allocation table depth (0x%x)\n", depth);
 203         av_free(wf);
 204         return NULL;
 205     }
 206
 207     if (!wf->nb_sectors) {
 208         av_free(wf->sectors);
 209         av_free(wf);
 210         return NULL;
 211     }
 212
 213     /* check length */
 214     length &= 0xFFFFFFFFFFFF;
 215     if (length > ((int64_t)wf->nb_sectors << wf->sector_bits)) {
 216         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);
 217         length = (int64_t)wf->nb_sectors <<  wf->sector_bits;
 218     }
 219     wf->length = length;
 220
 221     /* seek to intial sector */
 222     wf->position = 0;
 223     if (url_fseek(s->pb, (int64_t)wf->sectors[0] << WTV_SECTOR_BITS, SEEK_SET) < 0) {
 224         av_free(wf->sectors);
 225         av_free(wf);
 226         return NULL;
 227     }
 228
 229     wf->pb_filesystem = s->pb;
 230     buffer = av_malloc(1 << wf->sector_bits);
 231     if (!buffer) {
 232         av_free(wf->sectors);
 233         av_free(wf);
 234         return NULL;
 235     }
 236
 237     pb = av_alloc_put_byte(buffer, 1 << wf->sector_bits, 0, wf,
 238                            wtvfile_read_packet, NULL, wtvfile_seek);
 239     if (!pb) {
 240         av_free(buffer);
 241         av_free(wf->sectors);
 242         av_free(wf);
 243     }
 244     return pb;
 245 }
 246
 247 static const ff_asf_guid dir_entry_guid =
 248     {0x92,0xB7,0x74,0x91,0x59,0x70,0x70,0x44,0x88,0xDF,0x06,0x3B,0x82,0xCC,0x21,0x3D};
 249
 250 /**
 251  * Open file using filename
 252  * @param[in]  buf       directory buffer
 253  * @param      buf_size  directory buffer size
 254  * @param[in]  filename
 255  * @param      filename_size size of filename
 256  * @return NULL on error
 257  */
 258 static ByteIOContext * wtvfile_open2(AVFormatContext *s, const uint8_t *buf, int buf_size, const uint8_t *filename, int filename_size)
 259 {
 260     const uint8_t *buf_end = buf + buf_size;
 261
 262     while(buf + 48 <= buf_end) {
 263         int dir_length, name_size, first_sector, depth;
 264         uint64_t file_length;
 265         const uint8_t *name;
 266         if (ff_guidcmp(buf, dir_entry_guid)) {
 267             av_log(s, AV_LOG_ERROR, "unknown guid "PRI_GUID", expected dir_entry_guid; "
 268                    "remaining directory entries ignored\n", ARG_GUID(buf));
 269             break;
 270         }
 271         dir_length  = AV_RL16(buf + 16);
 272         file_length = AV_RL64(buf + 24);
 273         name_size   = 2 * AV_RL32(buf + 32);
 274         if (buf + 48 + name_size > buf_end) {
 275             av_log(s, AV_LOG_ERROR, "filename exceeds buffer size; remaining directory entries ignored\n");
 276             break;
 277         }
 278         first_sector = AV_RL32(buf + 40 + name_size);
 279         depth        = AV_RL32(buf + 44 + name_size);
 280
 281         /* compare file name; test optional null terminator */
 282         name = buf + 40;
 283         if (name_size >= filename_size &&
 284             !memcmp(name, filename, filename_size) &&
 285             (name_size < filename_size + 2 || !AV_RN16(name + filename_size)))
 286             return wtvfile_open_sector(first_sector, file_length, depth, s);
 287
 288         buf += dir_length;
 289     }
 290     return 0;
 291 }
 292
 293 #define wtvfile_open(s, buf, buf_size, filename) \
 294     wtvfile_open2(s, buf, buf_size, filename, sizeof(filename))
 295
 296 /**
 297  * Close file opened with wtvfile_open_sector(), or wtv_open()
 298  */
 299 static void wtvfile_close(ByteIOContext *pb)
 300 {
 301     WtvFile *wf = pb->opaque;
 302     av_free(wf->sectors);
 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     ByteIOContext *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 typedef struct {
 330     enum CodecID id;
 331     ff_asf_guid guid;
 332 } AVCodecGuid;
 333
 334 static enum CodecID ff_codec_guid_get_id(const AVCodecGuid *guids, ff_asf_guid guid)
 335 {
 336     int i;
 337     for (i = 0; guids[i].id != CODEC_ID_NONE; i++) {
 338         if (!ff_guidcmp(guids[i].guid, guid))
 339             return guids[i].id;
 340     }
 341     return CODEC_ID_NONE;
 342 }
 343
 344 /* WTV GUIDs */
 345 static const ff_asf_guid wtv_guid =
 346     {0xB7,0xD8,0x00,0x20,0x37,0x49,0xDA,0x11,0xA6,0x4E,0x00,0x07,0xE9,0x5E,0xAD,0x8D};
 347 static const ff_asf_guid metadata_guid =
 348     {0x5A,0xFE,0xD7,0x6D,0xC8,0x1D,0x8F,0x4A,0x99,0x22,0xFA,0xB1,0x1C,0x38,0x14,0x53};
 349 static const ff_asf_guid timestamp_guid =
 350     {0x5B,0x05,0xE6,0x1B,0x97,0xA9,0x49,0x43,0x88,0x17,0x1A,0x65,0x5A,0x29,0x8A,0x97};
 351 static const ff_asf_guid data_guid =
 352     {0x95,0xC3,0xD2,0xC2,0x7E,0x9A,0xDA,0x11,0x8B,0xF7,0x00,0x07,0xE9,0x5E,0xAD,0x8D};
 353 static const ff_asf_guid stream_guid =
 354     {0xED,0xA4,0x13,0x23,0x2D,0xBF,0x4F,0x45,0xAD,0x8A,0xD9,0x5B,0xA7,0xF9,0x1F,0xEE};
 355 static const ff_asf_guid stream2_guid =
 356     {0xA2,0xC3,0xD2,0xC2,0x7E,0x9A,0xDA,0x11,0x8B,0xF7,0x00,0x07,0xE9,0x5E,0xAD,0x8D};
 357 static const ff_asf_guid EVENTID_SubtitleSpanningEvent =
 358     {0x48,0xC0,0xCE,0x5D,0xB9,0xD0,0x63,0x41,0x87,0x2C,0x4F,0x32,0x22,0x3B,0xE8,0x8A};
 359 static const ff_asf_guid EVENTID_LanguageSpanningEvent =
 360     {0x6D,0x66,0x92,0xE2,0x02,0x9C,0x8D,0x44,0xAA,0x8D,0x78,0x1A,0x93,0xFD,0xC3,0x95};
 361 static const ff_asf_guid EVENTID_AudioDescriptorSpanningEvent =
 362     {0x1C,0xD4,0x7B,0x10,0xDA,0xA6,0x91,0x46,0x83,0x69,0x11,0xB2,0xCD,0xAA,0x28,0x8E};
 363 static const ff_asf_guid EVENTID_CtxADescriptorSpanningEvent =
 364     {0xE6,0xA2,0xB4,0x3A,0x47,0x42,0x34,0x4B,0x89,0x6C,0x30,0xAF,0xA5,0xD2,0x1C,0x24};
 365 static const ff_asf_guid EVENTID_CSDescriptorSpanningEvent =
 366     {0xD9,0x79,0xE7,0xEf,0xF0,0x97,0x86,0x47,0x80,0x0D,0x95,0xCF,0x50,0x5D,0xDC,0x66};
 367 static const ff_asf_guid EVENTID_DVBScramblingControlSpanningEvent =
 368     {0xC4,0xE1,0xD4,0x4B,0xA1,0x90,0x09,0x41,0x82,0x36,0x27,0xF0,0x0E,0x7D,0xCC,0x5B};
 369 static const ff_asf_guid EVENTID_StreamIDSpanningEvent =
 370     {0x68,0xAB,0xF1,0xCA,0x53,0xE1,0x41,0x4D,0xA6,0xB3,0xA7,0xC9,0x98,0xDB,0x75,0xEE};
 371 static const ff_asf_guid EVENTID_TeletextSpanningEvent =
 372     {0x50,0xD9,0x99,0x95,0x33,0x5F,0x17,0x46,0xAF,0x7C,0x1E,0x54,0xB5,0x10,0xDA,0xA3};
 373
 374 /* Windows media GUIDs */
 375
 376 #define MEDIASUBTYPE_BASE_GUID \
 377     0x00,0x00,0x10,0x00,0x80,0x00,0x00,0xAA,0x00,0x38,0x9B,0x71
 378
 379 /* Media types */
 380 static const ff_asf_guid mediatype_audio =
 381     {'a','u','d','s',MEDIASUBTYPE_BASE_GUID};
 382 static const ff_asf_guid mediatype_video =
 383     {'v','i','d','s',MEDIASUBTYPE_BASE_GUID};
 384 static const ff_asf_guid mediasubtype_mpeg1payload =
 385     {0x81,0xEB,0x36,0xE4,0x4F,0x52,0xCE,0x11,0x9F,0x53,0x00,0x20,0xAF,0x0B,0xA7,0x70};
 386 static const ff_asf_guid mediatype_mpeg2_sections =
 387     {0x6C,0x17,0x5F,0x45,0x06,0x4B,0xCE,0x47,0x9A,0xEF,0x8C,0xAE,0xF7,0x3D,0xF7,0xB5};
 388 static const ff_asf_guid mediatype_mpeg2_pes =
 389     {0x20,0x80,0x6D,0xE0,0x46,0xDB,0xCF,0x11,0xB4,0xD1,0x00,0x80,0x5F,0x6C,0xBB,0xEA};
 390 static const ff_asf_guid mediatype_mstvcaption =
 391     {0x89,0x8A,0x8B,0xB8,0x49,0xB0,0x80,0x4C,0xAD,0xCF,0x58,0x98,0x98,0x5E,0x22,0xC1};
 392
 393 /* Media subtypes */
 394 static const ff_asf_guid mediasubtype_cpfilters_processed =
 395     {0x28,0xBD,0xAD,0x46,0xD0,0x6F,0x96,0x47,0x93,0xB2,0x15,0x5C,0x51,0xDC,0x04,0x8D};
 396 static const ff_asf_guid mediasubtype_dvb_subtitle =
 397     {0xC3,0xCB,0xFF,0x34,0xB3,0xD5,0x71,0x41,0x90,0x02,0xD4,0xC6,0x03,0x01,0x69,0x7F};
 398 static const ff_asf_guid mediasubtype_teletext =
 399     {0xE3,0x76,0x2A,0xF7,0x0A,0xEB,0xD0,0x11,0xAC,0xE4,0x00,0x00,0xC0,0xCC,0x16,0xBA};
 400 static const ff_asf_guid mediasubtype_dtvccdata =
 401     {0xAA,0xDD,0x2A,0xF5,0xF0,0x36,0xF5,0x43,0x95,0xEA,0x6D,0x86,0x64,0x84,0x26,0x2A};
 402 static const ff_asf_guid mediasubtype_mpeg2_sections =
 403     {0x79,0x85,0x9F,0x4A,0xF8,0x6B,0x92,0x43,0x8A,0x6D,0xD2,0xDD,0x09,0xFA,0x78,0x61};
 404
 405 /* Formats */
 406 static const ff_asf_guid format_cpfilters_processed =
 407     {0x6F,0xB3,0x39,0x67,0x5F,0x1D,0xC2,0x4A,0x81,0x92,0x28,0xBB,0x0E,0x73,0xD1,0x6A};
 408 static const ff_asf_guid format_waveformatex =
 409     {0x81,0x9F,0x58,0x05,0x56,0xC3,0xCE,0x11,0xBF,0x01,0x00,0xAA,0x00,0x55,0x59,0x5A};
 410 static const ff_asf_guid format_videoinfo2 =
 411     {0xA0,0x76,0x2A,0xF7,0x0A,0xEB,0xD0,0x11,0xAC,0xE4,0x00,0x00,0xC0,0xCC,0x16,0xBA};
 412 static const ff_asf_guid format_mpeg2_video =
 413     {0xE3,0x80,0x6D,0xE0,0x46,0xDB,0xCF,0x11,0xB4,0xD1,0x00,0x80,0x5F,0x6C,0xBB,0xEA};
 414 static const ff_asf_guid format_none =
 415     {0xD6,0x17,0x64,0x0F,0x18,0xC3,0xD0,0x11,0xA4,0x3F,0x00,0xA0,0xC9,0x22,0x31,0x96};
 416
 417 static const AVCodecGuid video_guids[] = {
 418     {CODEC_ID_MPEG2VIDEO, {0x26,0x80,0x6D,0xE0,0x46,0xDB,0xCF,0x11,0xB4,0xD1,0x00,0x80,0x5F,0x6C,0xBB,0xEA}},
 419     {CODEC_ID_NONE}
 420 };
 421
 422 static const AVCodecGuid audio_guids[] = {
 423     {CODEC_ID_AC3,        {0x2C,0x80,0x6D,0xE0,0x46,0xDB,0xCF,0x11,0xB4,0xD1,0x00,0x80,0x5F,0x6C,0xBB,0xEA}},
 424     {CODEC_ID_EAC3,       {0xAF,0x87,0xFB,0xA7,0x02,0x2D,0xFB,0x42,0xA4,0xD4,0x05,0xCD,0x93,0x84,0x3B,0xDD}},
 425     {CODEC_ID_MP2,        {0x2B,0x80,0x6D,0xE0,0x46,0xDB,0xCF,0x11,0xB4,0xD1,0x00,0x80,0x5F,0x6C,0xBB,0xEA}},
 426     {CODEC_ID_NONE}
 427 };
 428
 429 static int read_probe(AVProbeData *p)
 430 {
 431     return ff_guidcmp(p->buf, wtv_guid) ? 0 : AVPROBE_SCORE_MAX;
 432 }
 433
 434 /**
 435  * Convert win32 FILETIME to ISO-8601 string
 436  */
 437 static void filetime_to_iso8601(char *buf, int buf_size, int64_t value)
 438 {
 439     time_t t = (value / 10000000LL) - 11644473600LL;
 440     strftime(buf, buf_size, "%Y-%m-%d %H:%M:%S", gmtime(&t));
 441 }
 442
 443 /**
 444  * Convert crazy time (100ns since 1 Jan 0001) to ISO-8601 string
 445  */
 446 static void crazytime_to_iso8601(char *buf, int buf_size, int64_t value)
 447 {
 448     time_t t = (value / 10000000LL) - 719162LL*86400LL;
 449     strftime(buf, buf_size, "%Y-%m-%d %H:%M:%S", gmtime(&t));
 450 }
 451
 452 /**
 453  * Convert OLE DATE to ISO-8601 string
 454  */
 455 static void oledate_to_iso8601(char *buf, int buf_size, int64_t value)
 456 {
 457     time_t t = 631112400LL + 86400*av_int2dbl(value);
 458     strftime(buf, buf_size, "%Y-%m-%d %H:%M:%S", gmtime(&t));
 459 }
 460
 461 static void get_attachment(AVFormatContext *s, ByteIOContext *pb, int length)
 462 {
 463     char mime[1024];
 464     char description[1024];
 465     unsigned int filesize;
 466     AVStream *st;
 467     int64_t pos = url_ftell(pb);
 468
 469     avio_get_str16le(pb, INT_MAX, mime, sizeof(mime));
 470     if (strcmp(mime, "image/jpeg"))
 471         goto done;
 472
 473     get_byte(pb);
 474     avio_get_str16le(pb, INT_MAX, description, sizeof(description));
 475     filesize = get_le32(pb);
 476     if (!filesize)
 477         goto done;
 478
 479     st = av_new_stream(s, 0);
 480     if (!st)
 481         goto done;
 482     av_metadata_set2(&st->metadata, "title", description, 0);
 483     st->codec->codec_id   = CODEC_ID_MJPEG;
 484     st->codec->codec_type = AVMEDIA_TYPE_ATTACHMENT;
 485     st->codec->extradata  = av_mallocz(filesize);
 486     if (!st->codec->extradata)
 487         goto done;
 488     st->codec->extradata_size = filesize;
 489     get_buffer(pb, st->codec->extradata, filesize);
 490 done:
 491     url_fseek(pb, pos + length, SEEK_SET);
 492 }
 493
 494 static void get_tag(AVFormatContext *s, ByteIOContext *pb, const char *key, int type, int length)
 495 {
 496     int buf_size = FFMAX(2*length, LEN_PRETTY_GUID) + 1;
 497     char *buf = av_malloc(buf_size);
 498     if (!buf)
 499         return;
 500
 501     if (type == 0 && length == 4) {
 502         snprintf(buf, buf_size, "%"PRIi32, get_le32(pb));
 503     } else if (type == 1) {
 504         avio_get_str16le(pb, length, buf, buf_size);
 505         if (!strlen(buf)) {
 506            av_free(buf);
 507            return;
 508         }
 509     } else if (type == 3 && length == 4) {
 510         strcpy(buf, get_le32(pb) ? "true" : "false");
 511     } else if (type == 4 && length == 8) {
 512         int64_t num = get_le64(pb);
 513         if (!strcmp(key, "WM/EncodingTime") ||
 514             !strcmp(key, "WM/MediaOriginalBroadcastDateTime"))
 515             filetime_to_iso8601(buf, buf_size, num);
 516         else if (!strcmp(key, "WM/WMRVEncodeTime") ||
 517                  !strcmp(key, "WM/WMRVEndTime"))
 518             crazytime_to_iso8601(buf, buf_size, num);
 519         else if (!strcmp(key, "WM/WMRVExpirationDate"))
 520             oledate_to_iso8601(buf, buf_size, num);
 521         else if (!strcmp(key, "WM/WMRVBitrate"))
 522             snprintf(buf, buf_size, "%f", av_int2dbl(num));
 523         else
 524             snprintf(buf, buf_size, "%"PRIi64, num);
 525     } else if (type == 5 && length == 2) {
 526         snprintf(buf, buf_size, "%"PRIi16, get_le16(pb));
 527     } else if (type == 6 && length == 16) {
 528         ff_asf_guid guid;
 529         get_buffer(pb, guid, 16);
 530         snprintf(buf, buf_size, PRI_PRETTY_GUID, ARG_PRETTY_GUID(guid));
 531     } else if (type == 2 && !strcmp(key, "WM/Picture")) {
 532         get_attachment(s, pb, length);
 533         av_freep(&buf);
 534         return;
 535     } else {
 536         av_freep(&buf);
 537         av_log(s, AV_LOG_WARNING, "unsupported metadata entry; key:%s, type:%d, length:0x%x\n", key, type, length);
 538         url_fskip(pb, length);
 539         return;
 540     }
 541
 542     av_metadata_set2(&s->metadata, key, buf, 0);
 543     av_freep(&buf);
 544 }
 545
 546 /**
 547  * Parse metadata entries
 548  */
 549 static void parse_legacy_attrib(AVFormatContext *s, ByteIOContext *pb)
 550 {
 551     ff_asf_guid guid;
 552     int length, type;
 553     while(!url_feof(pb)) {
 554         char key[1024];
 555         ff_get_guid(pb, &guid);
 556         type   = get_le32(pb);
 557         length = get_le32(pb);
 558         if (!length)
 559             break;
 560         if (ff_guidcmp(&guid, metadata_guid)) {
 561             av_log(s, AV_LOG_WARNING, "unknown guid "PRI_GUID", expected metadata_guid; "
 562                    "remaining metadata entries ignored\n", ARG_GUID(guid));
 563             break;
 564         }
 565         avio_get_str16le(pb, INT_MAX, key, sizeof(key));
 566         get_tag(s, pb, key, type, length);
 567     }
 568
 569     ff_metadata_conv(&s->metadata, NULL, ff_asf_metadata_conv);
 570 }
 571
 572 /**
 573  * parse VIDEOINFOHEADER2 structure
 574  * @return bytes consumed
 575  */
 576 static int parse_videoinfoheader2(AVFormatContext *s, AVStream *st)
 577 {
 578     WtvContext *wtv = s->priv_data;
 579     ByteIOContext *pb = wtv->pb;
 580
 581     url_fskip(pb, 72);  // picture aspect ratio is unreliable
 582     ff_get_bmp_header(pb, st);
 583
 584     return 72 + 40;
 585 }
 586
 587 /**
 588  * Parse MPEG1WAVEFORMATEX extradata structure
 589  */
 590 static void parse_mpeg1waveformatex(AVStream *st)
 591 {
 592     /* fwHeadLayer */
 593     switch (AV_RL16(st->codec->extradata)) {
 594     case 0x0001 : st->codec->codec_id = CODEC_ID_MP1; break;
 595     case 0x0002 : st->codec->codec_id = CODEC_ID_MP2; break;
 596     case 0x0004 : st->codec->codec_id = CODEC_ID_MP3; break;
 597     }
 598
 599     st->codec->bit_rate = AV_RL32(st->codec->extradata + 2); /* dwHeadBitrate */
 600
 601     /* dwHeadMode */
 602     switch (AV_RL16(st->codec->extradata + 6)) {
 603     case 1 : case 2 : case 4 : st->codec->channels = 2; break;
 604     case 8 :                   st->codec->channels = 1; break;
 605     }
 606 }
 607
 608 /**
 609  * Initialise stream
 610  * @param st Stream to initialise, or NULL to create and initialise new stream
 611  * @return NULL on error
 612  */
 613 static AVStream * new_stream(AVFormatContext *s, AVStream *st, int sid, int codec_type)
 614 {
 615     if (st) {
 616         if (st->codec->extradata) {
 617             av_freep(&st->codec->extradata);
 618             st->codec->extradata_size = 0;
 619         }
 620     } else {
 621         WtvStream *wst = av_mallocz(sizeof(WtvStream));
 622         if (!wst)
 623             return NULL;
 624         st = av_new_stream(s, sid);
 625         if (!st)
 626             return NULL;
 627         st->priv_data = wst;
 628     }
 629     st->codec->codec_type = codec_type;
 630     st->need_parsing      = AVSTREAM_PARSE_FULL;
 631     av_set_pts_info(st, 64, 1, 10000000);
 632     return st;
 633 }
 634
 635 /**
 636  * parse Media Type structure and populate stream
 637  * @param st         Stream, or NULL to create new stream
 638  * @param mediatype  Mediatype GUID
 639  * @param subtype    Subtype GUID
 640  * @param formattype Format GUID
 641  * @param size       Size of format buffer
 642  * @return NULL on error
 643  */
 644 static AVStream * parse_media_type(AVFormatContext *s, AVStream *st, int sid,
 645                                    ff_asf_guid mediatype, ff_asf_guid subtype,
 646                                    ff_asf_guid formattype, int size)
 647 {
 648     WtvContext *wtv = s->priv_data;
 649     ByteIOContext *pb = wtv->pb;
 650     if (!ff_guidcmp(subtype, mediasubtype_cpfilters_processed) &&
 651         !ff_guidcmp(formattype, format_cpfilters_processed)) {
 652         ff_asf_guid actual_subtype;
 653         ff_asf_guid actual_formattype;
 654
 655         if (size < 32) {
 656             av_log(s, AV_LOG_WARNING, "format buffer size underflow\n");
 657             url_fskip(pb, size);
 658             return NULL;
 659         }
 660
 661         url_fskip(pb, size - 32);
 662         ff_get_guid(pb, &actual_subtype);
 663         ff_get_guid(pb, &actual_formattype);
 664         url_fseek(pb, -size, SEEK_CUR);
 665
 666         st = parse_media_type(s, st, sid, mediatype, actual_subtype, actual_formattype, size - 32);
 667         url_fskip(pb, 32);
 668         return st;
 669     } else if (!ff_guidcmp(mediatype, mediatype_audio)) {
 670         st = new_stream(s, st, sid, AVMEDIA_TYPE_AUDIO);
 671         if (!st)
 672             return NULL;
 673         if (!ff_guidcmp(formattype, format_waveformatex)) {
 674             ff_get_wav_header(pb, st->codec, size);
 675         } else {
 676             if (ff_guidcmp(formattype, format_none))
 677                 av_log(s, AV_LOG_WARNING, "unknown formattype:"PRI_GUID"\n", ARG_GUID(formattype));
 678             url_fskip(pb, size);
 679         }
 680
 681         if (!memcmp(subtype + 4, (const uint8_t[]){MEDIASUBTYPE_BASE_GUID}, 12)) {
 682             st->codec->codec_id = ff_wav_codec_get_id(AV_RL32(subtype), st->codec->bits_per_coded_sample);
 683         } else if (!ff_guidcmp(subtype, mediasubtype_mpeg1payload)) {
 684             if (st->codec->extradata && st->codec->extradata_size >= 22)
 685                 parse_mpeg1waveformatex(st);
 686             else
 687                 av_log(s, AV_LOG_WARNING, "MPEG1WAVEFORMATEX underflow\n");
 688         } else {
 689             st->codec->codec_id = ff_codec_guid_get_id(audio_guids, subtype);
 690             if (st->codec->codec_id == CODEC_ID_NONE)
 691                 av_log(s, AV_LOG_WARNING, "unknown subtype:"PRI_GUID"\n", ARG_GUID(subtype));
 692         }
 693         return st;
 694     } else if (!ff_guidcmp(mediatype, mediatype_video)) {
 695         st = new_stream(s, st, sid, AVMEDIA_TYPE_VIDEO);
 696         if (!st)
 697             return NULL;
 698         if (!ff_guidcmp(formattype, format_videoinfo2)) {
 699             int consumed = parse_videoinfoheader2(s, st);
 700             url_fskip(pb, FFMAX(size - consumed, 0));
 701         } else if (!ff_guidcmp(formattype, format_mpeg2_video)) {
 702             int consumed = parse_videoinfoheader2(s, st);
 703             url_fskip(pb, FFMAX(size - consumed, 0));
 704         } else {
 705             if (ff_guidcmp(formattype, format_none))
 706                 av_log(s, AV_LOG_WARNING, "unknown formattype:"PRI_GUID"\n", ARG_GUID(formattype));
 707             url_fskip(pb, size);
 708         }
 709
 710         if (!memcmp(subtype + 4, (const uint8_t[]){MEDIASUBTYPE_BASE_GUID}, 12)) {
 711             st->codec->codec_id = ff_codec_get_id(ff_codec_bmp_tags, AV_RL32(subtype));
 712         } else {
 713             st->codec->codec_id = ff_codec_guid_get_id(video_guids, subtype);
 714         }
 715         if (st->codec->codec_id == CODEC_ID_NONE)
 716             av_log(s, AV_LOG_WARNING, "unknown subtype:"PRI_GUID"\n", ARG_GUID(subtype));
 717         return st;
 718     } else if (!ff_guidcmp(mediatype, mediatype_mpeg2_pes) &&
 719                !ff_guidcmp(subtype, mediasubtype_dvb_subtitle)) {
 720         st = new_stream(s, st, sid, AVMEDIA_TYPE_SUBTITLE);
 721         if (!st)
 722             return NULL;
 723         if (ff_guidcmp(formattype, format_none))
 724             av_log(s, AV_LOG_WARNING, "unknown formattype:"PRI_GUID"\n", ARG_GUID(formattype));
 725         url_fskip(pb, size);
 726         st->codec->codec_id = CODEC_ID_DVB_SUBTITLE;
 727         return st;
 728     } else if (!ff_guidcmp(mediatype, mediatype_mstvcaption) &&
 729                (!ff_guidcmp(subtype, mediasubtype_teletext) || !ff_guidcmp(subtype, mediasubtype_dtvccdata))) {
 730         st = new_stream(s, st, sid, AVMEDIA_TYPE_SUBTITLE);
 731         if (!st)
 732             return NULL;
 733         if (ff_guidcmp(formattype, format_none))
 734             av_log(s, AV_LOG_WARNING, "unknown formattype:"PRI_GUID"\n", ARG_GUID(formattype));
 735         url_fskip(pb, size);
 736         st->codec->codec_id   = CODEC_ID_DVB_TELETEXT;
 737         return st;
 738     } else if (!ff_guidcmp(mediatype, mediatype_mpeg2_sections) &&
 739                !ff_guidcmp(subtype, mediasubtype_mpeg2_sections)) {
 740         if (ff_guidcmp(formattype, format_none))
 741             av_log(s, AV_LOG_WARNING, "unknown formattype:"PRI_GUID"\n", ARG_GUID(formattype));
 742         url_fskip(pb, size);
 743         return NULL;
 744     }
 745
 746     av_log(s, AV_LOG_WARNING, "unknown media type, mediatype:"PRI_GUID
 747                               ", subtype:"PRI_GUID", formattype:"PRI_GUID"\n",
 748                               ARG_GUID(mediatype), ARG_GUID(subtype), ARG_GUID(formattype));
 749     url_fskip(pb, size);
 750     return NULL;
 751 }
 752
 753 enum {
 754     SEEK_TO_DATA = 0,
 755     SEEK_TO_PTS,
 756 };
 757
 758 /**
 759  * Parse WTV chunks
 760  * @param mode SEEK_TO_DATA or SEEK_TO_PTS
 761  * @param seekts timestamp
 762  * @param[out] len Length of data chunk
 763  * @return stream index of data chunk, or <0 on error
 764  */
 765 static int parse_chunks(AVFormatContext *s, int mode, int64_t seekts, int *len_ptr)
 766 {
 767     WtvContext *wtv = s->priv_data;
 768     ByteIOContext *pb = wtv->pb;
 769     while (!url_feof(pb)) {
 770         ff_asf_guid g;
 771         int len, sid, consumed;
 772
 773         ff_get_guid(pb, &g);
 774         len = get_le32(pb);
 775         if (len < 32)
 776             break;
 777         sid = get_le32(pb) & 0x7FFF;
 778         url_fskip(pb, 8);
 779         consumed = 32;
 780
 781         if (!ff_guidcmp(g, stream_guid)) {
 782             if (ff_find_stream_index(s, sid) < 0) {
 783                 ff_asf_guid mediatype, subtype, formattype;
 784                 int size;
 785                 consumed += 20;
 786                 url_fskip(pb, 16);
 787                 if (get_le32(pb)) {
 788                     url_fskip(pb, 8);
 789                     ff_get_guid(pb, &mediatype);
 790                     ff_get_guid(pb, &subtype);
 791                     url_fskip(pb, 12);
 792                     ff_get_guid(pb, &formattype);
 793                     size = get_le32(pb);
 794                     parse_media_type(s, 0, sid, mediatype, subtype, formattype, size);
 795                     consumed += 72 + size;
 796                 }
 797             }
 798         } else if (!ff_guidcmp(g, stream2_guid)) {
 799             int stream_index = ff_find_stream_index(s, sid);
 800             if (stream_index >= 0 && !((WtvStream*)s->streams[stream_index]->priv_data)->seen_data) {
 801                 ff_asf_guid mediatype, subtype, formattype;
 802                 int size;
 803                 url_fskip(pb, 12);
 804                 ff_get_guid(pb, &mediatype);
 805                 ff_get_guid(pb, &subtype);
 806                 url_fskip(pb, 12);
 807                 ff_get_guid(pb, &formattype);
 808                 size = get_le32(pb);
 809                 parse_media_type(s, s->streams[stream_index], sid, mediatype, subtype, formattype, size);
 810                 consumed += 76 + size;
 811             }
 812         } else if (!ff_guidcmp(g, EVENTID_AudioDescriptorSpanningEvent) ||
 813                    !ff_guidcmp(g, EVENTID_CtxADescriptorSpanningEvent) ||
 814                    !ff_guidcmp(g, EVENTID_CSDescriptorSpanningEvent) ||
 815                    !ff_guidcmp(g, EVENTID_StreamIDSpanningEvent) ||
 816                    !ff_guidcmp(g, EVENTID_SubtitleSpanningEvent) ||
 817                    !ff_guidcmp(g, EVENTID_TeletextSpanningEvent)) {
 818             int stream_index = ff_find_stream_index(s, sid);
 819             if (stream_index >= 0) {
 820                 AVStream *st = s->streams[stream_index];
 821                 uint8_t buf[258];
 822                 const uint8_t *pbuf = buf;
 823                 int buf_size;
 824
 825                 url_fskip(pb, 8);
 826                 consumed += 8;
 827                 if (!ff_guidcmp(g, EVENTID_CtxADescriptorSpanningEvent) ||
 828                     !ff_guidcmp(g, EVENTID_CSDescriptorSpanningEvent)) {
 829                     url_fskip(pb, 6);
 830                     consumed += 6;
 831                 }
 832
 833                 buf_size = FFMIN(len - consumed, sizeof(buf));
 834                 get_buffer(pb, buf, buf_size);
 835                 consumed += buf_size;
 836                 ff_parse_mpeg2_descriptor(s, st, 0, &pbuf, buf + buf_size, 0, 0, 0, 0);
 837             }
 838         } else if (!ff_guidcmp(g, EVENTID_DVBScramblingControlSpanningEvent)) {
 839             int stream_index = ff_find_stream_index(s, sid);
 840             if (stream_index >= 0) {
 841                 url_fskip(pb, 12);
 842                 if (get_le32(pb))
 843                     av_log(s, AV_LOG_WARNING, "DVB scrambled stream detected (st:%d), decoding will likely fail\n", stream_index);
 844                 consumed += 16;
 845             }
 846         } else if (!ff_guidcmp(g, EVENTID_LanguageSpanningEvent)) {
 847             int stream_index = ff_find_stream_index(s, sid);
 848             if (stream_index >= 0) {
 849                 AVStream *st = s->streams[stream_index];
 850                 uint8_t language[4];
 851                 url_fskip(pb, 12);
 852                 get_buffer(pb, language, 3);
 853                 if (language[0]) {
 854                     language[3] = 0;
 855                     av_metadata_set2(&st->metadata, "language", language, 0);
 856                 }
 857                 consumed += 15;
 858             }
 859         } else if (!ff_guidcmp(g, timestamp_guid)) {
 860             int stream_index = ff_find_stream_index(s, sid);
 861             if (stream_index >= 0) {
 862                 url_fskip(pb, 8);
 863                 wtv->pts = get_le64(pb);
 864                 consumed += 16;
 865                 if (wtv->pts == -1)
 866                     wtv->pts = AV_NOPTS_VALUE;
 867                 else {
 868                     wtv->last_valid_pts = wtv->pts;
 869                     if (wtv->epoch == AV_NOPTS_VALUE || wtv->pts < wtv->epoch)
 870                         wtv->epoch = wtv->pts;
 871                 if (mode == SEEK_TO_PTS && wtv->pts >= seekts) {
 872 #define WTV_PAD8(x) (((x) + 7) & ~7)
 873                     url_fskip(pb, WTV_PAD8(len) - consumed);
 874                     return 0;
 875                 }
 876                 }
 877             }
 878         } else if (!ff_guidcmp(g, data_guid)) {
 879             int stream_index = ff_find_stream_index(s, sid);
 880             if (mode == SEEK_TO_DATA && stream_index >= 0) {
 881                 WtvStream *wst = s->streams[stream_index]->priv_data;
 882                 wst->seen_data = 1;
 883                 if (len_ptr) {
 884                     *len_ptr = len;
 885                 }
 886                 return stream_index;
 887             }
 888         } else if (
 889             !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}) ||
 890             !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}) ||
 891             !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}) ||
 892             !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}) ||
 893             !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}) ||
 894             !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}) ||
 895             !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}) ||
 896             !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}) ||
 897             !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}) ||
 898             !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}) ||
 899             !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}) ||
 900             !ff_guidcmp(g, (const ff_asf_guid){0x1E,0xBE,0xC3,0xC5,0x43,0x92,0xDC,0x11,0x85,0xE5,0x00,0x12,0x3F,0x6F,0x73,0xB9}) ||
 901             !ff_guidcmp(g, (const ff_asf_guid){0x3B,0x86,0xA2,0xB1,0xEB,0x1E,0xC3,0x44,0x8C,0x88,0x1C,0xA3,0xFF,0xE3,0xE7,0x6A}) ||
 902             !ff_guidcmp(g, (const ff_asf_guid){0x4E,0x7F,0x4C,0x5B,0xC4,0xD0,0x38,0x4B,0xA8,0x3E,0x21,0x7F,0x7B,0xBF,0x52,0xE7}) ||
 903             !ff_guidcmp(g, (const ff_asf_guid){0x63,0x36,0xEB,0xFE,0xA1,0x7E,0xD9,0x11,0x83,0x08,0x00,0x07,0xE9,0x5E,0xAD,0x8D}) ||
 904             !ff_guidcmp(g, (const ff_asf_guid){0x70,0xE9,0xF1,0xF8,0x89,0xA4,0x4C,0x4D,0x83,0x73,0xB8,0x12,0xE0,0xD5,0xF8,0x1E}) ||
 905             !ff_guidcmp(g, (const ff_asf_guid){0x96,0xC3,0xD2,0xC2,0x7E,0x9A,0xDA,0x11,0x8B,0xF7,0x00,0x07,0xE9,0x5E,0xAD,0x8D}) ||
 906             !ff_guidcmp(g, (const ff_asf_guid){0x97,0xC3,0xD2,0xC2,0x7E,0x9A,0xDA,0x11,0x8B,0xF7,0x00,0x07,0xE9,0x5E,0xAD,0x8D}) ||
 907             !ff_guidcmp(g, (const ff_asf_guid){0xA1,0xC3,0xD2,0xC2,0x7E,0x9A,0xDA,0x11,0x8B,0xF7,0x00,0x07,0xE9,0x5E,0xAD,0x8D})) {
 908             //ignore known guids
 909         } else
 910             av_log(s, AV_LOG_WARNING, "unsupported chunk:"PRI_GUID"\n", ARG_GUID(g));
 911
 912         url_fskip(pb, WTV_PAD8(len) - consumed);
 913     }
 914     return AVERROR_EOF;
 915 }
 916
 917 /* declare utf16le strings */
 918 #define _ , 0,
 919 static const uint8_t timeline_le16[] =
 920     {'t'_'i'_'m'_'e'_'l'_'i'_'n'_'e', 0};
 921 static const uint8_t table_0_entries_legacy_attrib_le16[] =
 922     {'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};
 923 static const uint8_t table_0_entries_time_le16[] =
 924     {'t'_'a'_'b'_'l'_'e'_'.'_'0'_'.'_'e'_'n'_'t'_'r'_'i'_'e'_'s'_'.'_'t'_'i'_'m'_'e', 0};
 925 static const uint8_t timeline_table_0_entries_Events_le16[] =
 926     {'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};
 927 #undef _
 928
 929 static int read_header(AVFormatContext *s, AVFormatParameters *ap)
 930 {
 931     WtvContext *wtv = s->priv_data;
 932     int root_sector, root_size;
 933     uint8_t root[WTV_SECTOR_SIZE];
 934     ByteIOContext *pb;
 935     int64_t timeline_pos;
 936     int ret;
 937
 938     wtv->epoch          =
 939     wtv->pts            =
 940     wtv->last_valid_pts = AV_NOPTS_VALUE;
 941
 942     /* read root directory sector */
 943     url_fskip(s->pb, 0x30);
 944     root_size = get_le32(s->pb);
 945     if (root_size > sizeof(root)) {
 946         av_log(s, AV_LOG_ERROR, "root directory size exceeds sector size\n");
 947         return AVERROR_INVALIDDATA;
 948     }
 949     url_fskip(s->pb, 4);
 950     root_sector = get_le32(s->pb);
 951
 952     url_fseek(s->pb, root_sector << WTV_SECTOR_BITS, SEEK_SET);
 953     root_size = get_buffer(s->pb, root, root_size);
 954     if (root_size < 0)
 955         return AVERROR_INVALIDDATA;
 956
 957     /* parse chunks up until first data chunk */
 958     wtv->pb = wtvfile_open(s, root, root_size, timeline_le16);
 959     if (!wtv->pb) {
 960         av_log(s, AV_LOG_ERROR, "timeline data missing\n");
 961         return AVERROR_INVALIDDATA;
 962     }
 963
 964     ret = parse_chunks(s, SEEK_TO_DATA, 0, 0);
 965     if (ret < 0)
 966         return ret;
 967     url_fseek(wtv->pb, -32, SEEK_CUR);
 968
 969     timeline_pos = url_ftell(s->pb); // save before opening another file
 970
 971     /* read metadata */
 972     pb = wtvfile_open(s, root, root_size, table_0_entries_legacy_attrib_le16);
 973     if (pb) {
 974         parse_legacy_attrib(s, pb);
 975         wtvfile_close(pb);
 976     }
 977
 978     /* read seek index */
 979     if (s->nb_streams) {
 980         AVStream *st = s->streams[0];
 981         pb = wtvfile_open(s, root, root_size, table_0_entries_time_le16);
 982         if (pb) {
 983             while(1) {
 984                 uint64_t timestamp = get_le64(pb);
 985                 uint64_t frame_nb  = get_le64(pb);
 986                 if (url_feof(pb))
 987                     break;
 988                 ff_add_index_entry(&wtv->index_entries, &wtv->nb_index_entries, &wtv->index_entries_allocated_size,
 989                                    0, timestamp, frame_nb, 0, AVINDEX_KEYFRAME);
 990             }
 991             wtvfile_close(pb);
 992
 993             if (wtv->nb_index_entries) {
 994                 pb = wtvfile_open(s, root, root_size, timeline_table_0_entries_Events_le16);
 995                 if (pb) {
 996                     int i;
 997                     while (1) {
 998                         uint64_t frame_nb = get_le64(pb);
 999                         uint64_t position = get_le64(pb);
1000                         if (url_feof(pb))
1001                             break;
1002                         for (i = wtv->nb_index_entries - 1; i >= 0; i--) {
1003                             AVIndexEntry *e = wtv->index_entries + i;
1004                             if (frame_nb > e->size)
1005                                 break;
1006                             if (position > e->pos)
1007                                 e->pos = position;
1008                         }
1009                     }
1010                     wtvfile_close(pb);
1011                     st->duration = wtv->index_entries[wtv->nb_index_entries - 1].timestamp;
1012                 }
1013             }
1014         }
1015     }
1016
1017     url_fseek(s->pb, timeline_pos, SEEK_SET);
1018     return 0;
1019 }
1020
1021 static int read_packet(AVFormatContext *s, AVPacket *pkt)
1022 {
1023     WtvContext *wtv = s->priv_data;
1024     ByteIOContext *pb = wtv->pb;
1025     int stream_index, len, ret;
1026
1027     stream_index = parse_chunks(s, SEEK_TO_DATA, 0, &len);
1028     if (stream_index < 0)
1029         return stream_index;
1030
1031     ret = av_get_packet(pb, pkt, len - 32);
1032     if (ret < 0)
1033         return ret;
1034     pkt->stream_index = stream_index;
1035     pkt->pts          = wtv->pts;
1036     url_fskip(pb, WTV_PAD8(len) - len);
1037     return 0;
1038 }
1039
1040 static int read_seek(AVFormatContext *s, int stream_index,
1041                      int64_t ts, int flags)
1042 {
1043     WtvContext *wtv = s->priv_data;
1044     ByteIOContext *pb = wtv->pb;
1045     AVStream *st = s->streams[0];
1046     int64_t ts_relative;
1047     int i;
1048
1049     if ((flags & AVSEEK_FLAG_FRAME) || (flags & AVSEEK_FLAG_BYTE))
1050         return AVERROR_NOTSUPP;
1051
1052     /* timestamp adjustment is required because wtv->pts values are absolute,
1053      * whereas AVIndexEntry->timestamp values are relative to epoch. */
1054     ts_relative = ts;
1055     if (wtv->epoch != AV_NOPTS_VALUE)
1056         ts_relative -= wtv->epoch;
1057
1058     i = ff_index_search_timestamp(wtv->index_entries, wtv->nb_index_entries, ts_relative, flags);
1059     if (i < 0) {
1060         if (wtv->last_valid_pts == AV_NOPTS_VALUE || ts < wtv->last_valid_pts)
1061             url_fseek(pb, 0, SEEK_SET);
1062         else if (st->duration != AV_NOPTS_VALUE && ts_relative > st->duration && wtv->nb_index_entries)
1063             url_fseek(pb, wtv->index_entries[wtv->nb_index_entries - 1].pos, SEEK_SET);
1064         if (parse_chunks(s, SEEK_TO_PTS, ts, 0) < 0)
1065             return AVERROR(ERANGE);
1066         return 0;
1067     }
1068     wtv->pts = wtv->index_entries[i].timestamp;
1069     if (wtv->epoch != AV_NOPTS_VALUE)
1070         wtv->pts += wtv->epoch;
1071     wtv->last_valid_pts = wtv->pts;
1072     url_fseek(pb, wtv->index_entries[i].pos, SEEK_SET);
1073     return 0;
1074 }
1075
1076 static int read_close(AVFormatContext *s)
1077 {
1078     WtvContext *wtv = s->priv_data;
1079     wtvfile_close(wtv->pb);
1080     return 0;
1081 }
1082
1083 AVInputFormat ff_wtv_demuxer = {
1084     .name           = "wtv",
1085     .long_name      = NULL_IF_CONFIG_SMALL("Windows Television (WTV)"),
1086     .priv_data_size = sizeof(WtvContext),
1087     .read_probe     = read_probe,
1088     .read_header    = read_header,
1089     .read_packet    = read_packet,
1090     .read_seek      = read_seek,
1091     .read_close     = read_close,
1092     .flags          = AVFMT_SHOW_IDS,
1093 };