rename wtv.c to wtvdec.c
[ffmpeg.git] / libavformat / wtvdec.c
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 "internal.h"
32 #include "riff.h"
33 #include "asf.h"
34 #include "mpegts.h"
35 #include <strings.h>
36
37 /* Macros for formating GUIDs */
38 #define PRI_PRETTY_GUID \
39     "%08x-%04x-%04x-%02x%02x%02x%02x%02x%02x%02x%02x"
40 #define ARG_PRETTY_GUID(g) \
41     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]
42 #define LEN_PRETTY_GUID 34
43
44 /*
45  *
46  * File system routines
47  *
48  */
49
50 #define WTV_SECTOR_BITS    12
51 #define WTV_SECTOR_SIZE    (1 << WTV_SECTOR_BITS)
52 #define WTV_BIGSECTOR_BITS 18
53
54 typedef struct {
55     AVIOContext *pb_filesystem;  /** file system (AVFormatContext->pb) */
56
57     int sector_bits;     /** sector shift bits; used to convert sector number into pb_filesystem offset */
58     uint32_t *sectors;   /** file allocation table */
59     int nb_sectors;      /** number of sectors */
60
61     int error;
62     int64_t position;
63     int64_t length;
64 } WtvFile;
65
66 /**
67  * @return bytes read, 0 on end of file, or <0 on error
68  */
69 static int wtvfile_read_packet(void *opaque, uint8_t *buf, int buf_size)
70 {
71     WtvFile *wf = opaque;
72     AVIOContext *pb = wf->pb_filesystem;
73     int nread = 0;
74
75     if (wf->error || pb->error)
76         return -1;
77     if (wf->position >= wf->length || url_feof(pb))
78         return 0;
79
80     buf_size = FFMIN(buf_size, wf->length - wf->position);
81     while(nread < buf_size) {
82         int n;
83         int remaining_in_sector = (1 << wf->sector_bits) - (wf->position & ((1 << wf->sector_bits) - 1));
84         int read_request        = FFMIN(buf_size - nread, remaining_in_sector);
85
86         n = avio_read(pb, buf, read_request);
87         if (n <= 0)
88             break;
89         nread += n;
90         buf += n;
91         wf->position += n;
92         if (n == remaining_in_sector) {
93             int i = wf->position >> wf->sector_bits;
94             if (i >= wf->nb_sectors ||
95                 (wf->sectors[i] != wf->sectors[i - 1] + (1 << (wf->sector_bits - WTV_SECTOR_BITS)) &&
96                 avio_seek(pb, (int64_t)wf->sectors[i] << WTV_SECTOR_BITS, SEEK_SET) < 0)) {
97                 wf->error = 1;
98                 break;
99             }
100         }
101     }
102     return nread;
103 }
104
105 /**
106  * @return position (or file length)
107  */
108 static int64_t wtvfile_seek(void *opaque, int64_t offset, int whence)
109 {
110     WtvFile *wf = opaque;
111     AVIOContext *pb = wf->pb_filesystem;
112
113     if (whence == AVSEEK_SIZE)
114         return wf->length;
115     else if (whence == SEEK_CUR)
116         offset = wf->position + offset;
117     else if (whence == SEEK_END)
118         offset = wf->length;
119
120     wf->error = offset < 0 || offset >= wf->length ||
121                 avio_seek(pb, ((int64_t)wf->sectors[offset >> wf->sector_bits] << WTV_SECTOR_BITS)
122                               + (offset & ((1 << wf->sector_bits) - 1)), SEEK_SET) < 0;
123     wf->position = offset;
124     return offset;
125 }
126
127 /**
128  * read non-zero integers (le32) from input stream
129  * @param pb
130  * @param[out] data destination
131  * @param     count maximum number of integers to read
132  * @return    total number of integers read
133  */
134 static int read_ints(AVIOContext *pb, uint32_t *data, int count)
135 {
136     int i, total = 0;
137     for (i = 0; i < count; i++) {
138         if ((data[total] = avio_rl32(pb)))
139            total++;
140     }
141     return total;
142 }
143
144 /**
145  * Open file
146  * @param first_sector  First sector
147  * @param length        Length of file (bytes)
148  * @param depth         File allocation table depth
149  * @return NULL on error
150  */
151 static AVIOContext * wtvfile_open_sector(int first_sector, uint64_t length, int depth, AVFormatContext *s)
152 {
153     AVIOContext *pb;
154     WtvFile *wf;
155     uint8_t *buffer;
156
157     if (avio_seek(s->pb, first_sector << WTV_SECTOR_BITS, SEEK_SET) < 0)
158         return NULL;
159
160     wf = av_mallocz(sizeof(WtvFile));
161     if (!wf)
162         return NULL;
163
164     if (depth == 0) {
165         wf->sectors = av_malloc(sizeof(uint32_t));
166         if (!wf->sectors) {
167             av_free(wf);
168             return NULL;
169         }
170         wf->sectors[0]  = first_sector;
171         wf->nb_sectors  = 1;
172         wf->sector_bits = WTV_SECTOR_BITS;
173     } else if (depth == 1) {
174         wf->sectors = av_malloc(WTV_SECTOR_SIZE);
175         if (!wf->sectors) {
176             av_free(wf);
177             return NULL;
178         }
179         wf->nb_sectors  = read_ints(s->pb, wf->sectors, WTV_SECTOR_SIZE / 4);
180         wf->sector_bits = length & (1ULL<<63) ? WTV_SECTOR_BITS : WTV_BIGSECTOR_BITS;
181     } else if (depth == 2) {
182         uint32_t sectors1[WTV_SECTOR_SIZE / 4];
183         int nb_sectors1 = read_ints(s->pb, sectors1, WTV_SECTOR_SIZE / 4);
184         int i;
185
186         wf->sectors = av_malloc(nb_sectors1 << WTV_SECTOR_BITS);
187         if (!wf->sectors) {
188             av_free(wf);
189             return NULL;
190         }
191         wf->nb_sectors = 0;
192         for (i = 0; i < nb_sectors1; i++) {
193             if (avio_seek(s->pb, (int64_t)sectors1[i] << WTV_SECTOR_BITS, SEEK_SET) < 0)
194                 break;
195             wf->nb_sectors += read_ints(s->pb, wf->sectors + i * WTV_SECTOR_SIZE / 4, WTV_SECTOR_SIZE / 4);
196         }
197         wf->sector_bits = length & (1ULL<<63) ? WTV_SECTOR_BITS : WTV_BIGSECTOR_BITS;
198     } else {
199         av_log(s, AV_LOG_ERROR, "unsupported file allocation table depth (0x%x)\n", depth);
200         av_free(wf);
201         return NULL;
202     }
203
204     if (!wf->nb_sectors) {
205         av_free(wf->sectors);
206         av_free(wf);
207         return NULL;
208     }
209
210     /* check length */
211     length &= 0xFFFFFFFFFFFF;
212     if (length > ((int64_t)wf->nb_sectors << wf->sector_bits)) {
213         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);
214         length = (int64_t)wf->nb_sectors <<  wf->sector_bits;
215     }
216     wf->length = length;
217
218     /* seek to intial sector */
219     wf->position = 0;
220     if (avio_seek(s->pb, (int64_t)wf->sectors[0] << WTV_SECTOR_BITS, SEEK_SET) < 0) {
221         av_free(wf->sectors);
222         av_free(wf);
223         return NULL;
224     }
225
226     wf->pb_filesystem = s->pb;
227     buffer = av_malloc(1 << wf->sector_bits);
228     if (!buffer) {
229         av_free(wf->sectors);
230         av_free(wf);
231         return NULL;
232     }
233
234     pb = avio_alloc_context(buffer, 1 << wf->sector_bits, 0, wf,
235                            wtvfile_read_packet, NULL, wtvfile_seek);
236     if (!pb) {
237         av_free(buffer);
238         av_free(wf->sectors);
239         av_free(wf);
240     }
241     return pb;
242 }
243
244 static const ff_asf_guid dir_entry_guid =
245     {0x92,0xB7,0x74,0x91,0x59,0x70,0x70,0x44,0x88,0xDF,0x06,0x3B,0x82,0xCC,0x21,0x3D};
246
247 /**
248  * Open file using filename
249  * @param[in]  buf       directory buffer
250  * @param      buf_size  directory buffer size
251  * @param[in]  filename
252  * @param      filename_size size of filename
253  * @return NULL on error
254  */
255 static AVIOContext * wtvfile_open2(AVFormatContext *s, const uint8_t *buf, int buf_size, const uint8_t *filename, int filename_size)
256 {
257     const uint8_t *buf_end = buf + buf_size;
258
259     while(buf + 48 <= buf_end) {
260         int dir_length, name_size, first_sector, depth;
261         uint64_t file_length;
262         const uint8_t *name;
263         if (ff_guidcmp(buf, dir_entry_guid)) {
264             av_log(s, AV_LOG_ERROR, "unknown guid "FF_PRI_GUID", expected dir_entry_guid; "
265                    "remaining directory entries ignored\n", FF_ARG_GUID(buf));
266             break;
267         }
268         dir_length  = AV_RL16(buf + 16);
269         file_length = AV_RL64(buf + 24);
270         name_size   = 2 * AV_RL32(buf + 32);
271         if (buf + 48 + name_size > buf_end) {
272             av_log(s, AV_LOG_ERROR, "filename exceeds buffer size; remaining directory entries ignored\n");
273             break;
274         }
275         first_sector = AV_RL32(buf + 40 + name_size);
276         depth        = AV_RL32(buf + 44 + name_size);
277
278         /* compare file name; test optional null terminator */
279         name = buf + 40;
280         if (name_size >= filename_size &&
281             !memcmp(name, filename, filename_size) &&
282             (name_size < filename_size + 2 || !AV_RN16(name + filename_size)))
283             return wtvfile_open_sector(first_sector, file_length, depth, s);
284
285         buf += dir_length;
286     }
287     return 0;
288 }
289
290 #define wtvfile_open(s, buf, buf_size, filename) \
291     wtvfile_open2(s, buf, buf_size, filename, sizeof(filename))
292
293 /**
294  * Close file opened with wtvfile_open_sector(), or wtv_open()
295  */
296 static void wtvfile_close(AVIOContext *pb)
297 {
298     WtvFile *wf = pb->opaque;
299     av_free(wf->sectors);
300     av_free(pb);
301 }
302
303 /*
304  *
305  * Main demuxer
306  *
307  */
308
309 typedef struct {
310     int seen_data;
311 } WtvStream;
312
313 typedef struct {
314     AVIOContext *pb;       /** timeline file */
315     int64_t epoch;
316     int64_t pts;             /** pts for next data chunk */
317     int64_t last_valid_pts;  /** latest valid pts, used for interative seeking */
318
319     /* maintain private seek index, as the AVIndexEntry->pos is relative to the
320        start of the 'timeline' file, not the file system (AVFormatContext->pb) */
321     AVIndexEntry *index_entries;
322     int nb_index_entries;
323     unsigned int index_entries_allocated_size;
324 } WtvContext;
325
326 /* WTV GUIDs */
327 static const ff_asf_guid wtv_guid =
328     {0xB7,0xD8,0x00,0x20,0x37,0x49,0xDA,0x11,0xA6,0x4E,0x00,0x07,0xE9,0x5E,0xAD,0x8D};
329 static const ff_asf_guid metadata_guid =
330     {0x5A,0xFE,0xD7,0x6D,0xC8,0x1D,0x8F,0x4A,0x99,0x22,0xFA,0xB1,0x1C,0x38,0x14,0x53};
331 static const ff_asf_guid timestamp_guid =
332     {0x5B,0x05,0xE6,0x1B,0x97,0xA9,0x49,0x43,0x88,0x17,0x1A,0x65,0x5A,0x29,0x8A,0x97};
333 static const ff_asf_guid data_guid =
334     {0x95,0xC3,0xD2,0xC2,0x7E,0x9A,0xDA,0x11,0x8B,0xF7,0x00,0x07,0xE9,0x5E,0xAD,0x8D};
335 static const ff_asf_guid stream_guid =
336     {0xED,0xA4,0x13,0x23,0x2D,0xBF,0x4F,0x45,0xAD,0x8A,0xD9,0x5B,0xA7,0xF9,0x1F,0xEE};
337 static const ff_asf_guid stream2_guid =
338     {0xA2,0xC3,0xD2,0xC2,0x7E,0x9A,0xDA,0x11,0x8B,0xF7,0x00,0x07,0xE9,0x5E,0xAD,0x8D};
339 static const ff_asf_guid EVENTID_SubtitleSpanningEvent =
340     {0x48,0xC0,0xCE,0x5D,0xB9,0xD0,0x63,0x41,0x87,0x2C,0x4F,0x32,0x22,0x3B,0xE8,0x8A};
341 static const ff_asf_guid EVENTID_LanguageSpanningEvent =
342     {0x6D,0x66,0x92,0xE2,0x02,0x9C,0x8D,0x44,0xAA,0x8D,0x78,0x1A,0x93,0xFD,0xC3,0x95};
343 static const ff_asf_guid EVENTID_AudioDescriptorSpanningEvent =
344     {0x1C,0xD4,0x7B,0x10,0xDA,0xA6,0x91,0x46,0x83,0x69,0x11,0xB2,0xCD,0xAA,0x28,0x8E};
345 static const ff_asf_guid EVENTID_CtxADescriptorSpanningEvent =
346     {0xE6,0xA2,0xB4,0x3A,0x47,0x42,0x34,0x4B,0x89,0x6C,0x30,0xAF,0xA5,0xD2,0x1C,0x24};
347 static const ff_asf_guid EVENTID_CSDescriptorSpanningEvent =
348     {0xD9,0x79,0xE7,0xEf,0xF0,0x97,0x86,0x47,0x80,0x0D,0x95,0xCF,0x50,0x5D,0xDC,0x66};
349 static const ff_asf_guid EVENTID_DVBScramblingControlSpanningEvent =
350     {0xC4,0xE1,0xD4,0x4B,0xA1,0x90,0x09,0x41,0x82,0x36,0x27,0xF0,0x0E,0x7D,0xCC,0x5B};
351 static const ff_asf_guid EVENTID_StreamIDSpanningEvent =
352     {0x68,0xAB,0xF1,0xCA,0x53,0xE1,0x41,0x4D,0xA6,0xB3,0xA7,0xC9,0x98,0xDB,0x75,0xEE};
353 static const ff_asf_guid EVENTID_TeletextSpanningEvent =
354     {0x50,0xD9,0x99,0x95,0x33,0x5F,0x17,0x46,0xAF,0x7C,0x1E,0x54,0xB5,0x10,0xDA,0xA3};
355 static const ff_asf_guid EVENTID_AudioTypeSpanningEvent =
356     {0xBE,0xBF,0x1C,0x50,0x49,0xB8,0xCE,0x42,0x9B,0xE9,0x3D,0xB8,0x69,0xFB,0x82,0xB3};
357
358 /* Windows media GUIDs */
359
360 /* Media types */
361 static const ff_asf_guid mediatype_audio =
362     {'a','u','d','s',FF_MEDIASUBTYPE_BASE_GUID};
363 static const ff_asf_guid mediatype_video =
364     {'v','i','d','s',FF_MEDIASUBTYPE_BASE_GUID};
365 static const ff_asf_guid mediasubtype_mpeg1payload =
366     {0x81,0xEB,0x36,0xE4,0x4F,0x52,0xCE,0x11,0x9F,0x53,0x00,0x20,0xAF,0x0B,0xA7,0x70};
367 static const ff_asf_guid mediatype_mpeg2_sections =
368     {0x6C,0x17,0x5F,0x45,0x06,0x4B,0xCE,0x47,0x9A,0xEF,0x8C,0xAE,0xF7,0x3D,0xF7,0xB5};
369 static const ff_asf_guid mediatype_mpeg2_pes =
370     {0x20,0x80,0x6D,0xE0,0x46,0xDB,0xCF,0x11,0xB4,0xD1,0x00,0x80,0x5F,0x6C,0xBB,0xEA};
371 static const ff_asf_guid mediatype_mstvcaption =
372     {0x89,0x8A,0x8B,0xB8,0x49,0xB0,0x80,0x4C,0xAD,0xCF,0x58,0x98,0x98,0x5E,0x22,0xC1};
373
374 /* Media subtypes */
375 static const ff_asf_guid mediasubtype_cpfilters_processed =
376     {0x28,0xBD,0xAD,0x46,0xD0,0x6F,0x96,0x47,0x93,0xB2,0x15,0x5C,0x51,0xDC,0x04,0x8D};
377 static const ff_asf_guid mediasubtype_dvb_subtitle =
378     {0xC3,0xCB,0xFF,0x34,0xB3,0xD5,0x71,0x41,0x90,0x02,0xD4,0xC6,0x03,0x01,0x69,0x7F};
379 static const ff_asf_guid mediasubtype_teletext =
380     {0xE3,0x76,0x2A,0xF7,0x0A,0xEB,0xD0,0x11,0xAC,0xE4,0x00,0x00,0xC0,0xCC,0x16,0xBA};
381 static const ff_asf_guid mediasubtype_dtvccdata =
382     {0xAA,0xDD,0x2A,0xF5,0xF0,0x36,0xF5,0x43,0x95,0xEA,0x6D,0x86,0x64,0x84,0x26,0x2A};
383 static const ff_asf_guid mediasubtype_mpeg2_sections =
384     {0x79,0x85,0x9F,0x4A,0xF8,0x6B,0x92,0x43,0x8A,0x6D,0xD2,0xDD,0x09,0xFA,0x78,0x61};
385
386 /* Formats */
387 static const ff_asf_guid format_cpfilters_processed =
388     {0x6F,0xB3,0x39,0x67,0x5F,0x1D,0xC2,0x4A,0x81,0x92,0x28,0xBB,0x0E,0x73,0xD1,0x6A};
389 static const ff_asf_guid format_waveformatex =
390     {0x81,0x9F,0x58,0x05,0x56,0xC3,0xCE,0x11,0xBF,0x01,0x00,0xAA,0x00,0x55,0x59,0x5A};
391 static const ff_asf_guid format_videoinfo2 =
392     {0xA0,0x76,0x2A,0xF7,0x0A,0xEB,0xD0,0x11,0xAC,0xE4,0x00,0x00,0xC0,0xCC,0x16,0xBA};
393 static const ff_asf_guid format_mpeg2_video =
394     {0xE3,0x80,0x6D,0xE0,0x46,0xDB,0xCF,0x11,0xB4,0xD1,0x00,0x80,0x5F,0x6C,0xBB,0xEA};
395 static const ff_asf_guid format_none =
396     {0xD6,0x17,0x64,0x0F,0x18,0xC3,0xD0,0x11,0xA4,0x3F,0x00,0xA0,0xC9,0x22,0x31,0x96};
397
398 static const AVCodecGuid video_guids[] = {
399     {CODEC_ID_MPEG2VIDEO, {0x26,0x80,0x6D,0xE0,0x46,0xDB,0xCF,0x11,0xB4,0xD1,0x00,0x80,0x5F,0x6C,0xBB,0xEA}},
400     {CODEC_ID_NONE}
401 };
402
403 static int read_probe(AVProbeData *p)
404 {
405     return ff_guidcmp(p->buf, wtv_guid) ? 0 : AVPROBE_SCORE_MAX;
406 }
407
408 /**
409  * Convert win32 FILETIME to ISO-8601 string
410  */
411 static void filetime_to_iso8601(char *buf, int buf_size, int64_t value)
412 {
413     time_t t = (value / 10000000LL) - 11644473600LL;
414     strftime(buf, buf_size, "%Y-%m-%d %H:%M:%S", gmtime(&t));
415 }
416
417 /**
418  * Convert crazy time (100ns since 1 Jan 0001) to ISO-8601 string
419  */
420 static void crazytime_to_iso8601(char *buf, int buf_size, int64_t value)
421 {
422     time_t t = (value / 10000000LL) - 719162LL*86400LL;
423     strftime(buf, buf_size, "%Y-%m-%d %H:%M:%S", gmtime(&t));
424 }
425
426 /**
427  * Convert OLE DATE to ISO-8601 string
428  */
429 static void oledate_to_iso8601(char *buf, int buf_size, int64_t value)
430 {
431     time_t t = 631112400LL + 86400*av_int2dbl(value);
432     strftime(buf, buf_size, "%Y-%m-%d %H:%M:%S", gmtime(&t));
433 }
434
435 static void get_attachment(AVFormatContext *s, AVIOContext *pb, int length)
436 {
437     char mime[1024];
438     char description[1024];
439     unsigned int filesize;
440     AVStream *st;
441     int64_t pos = avio_tell(pb);
442
443     avio_get_str16le(pb, INT_MAX, mime, sizeof(mime));
444     if (strcmp(mime, "image/jpeg"))
445         goto done;
446
447     avio_r8(pb);
448     avio_get_str16le(pb, INT_MAX, description, sizeof(description));
449     filesize = avio_rl32(pb);
450     if (!filesize)
451         goto done;
452
453     st = av_new_stream(s, 0);
454     if (!st)
455         goto done;
456     av_metadata_set2(&st->metadata, "title", description, 0);
457     st->codec->codec_id   = CODEC_ID_MJPEG;
458     st->codec->codec_type = AVMEDIA_TYPE_ATTACHMENT;
459     st->codec->extradata  = av_mallocz(filesize);
460     if (!st->codec->extradata)
461         goto done;
462     st->codec->extradata_size = filesize;
463     avio_read(pb, st->codec->extradata, filesize);
464 done:
465     avio_seek(pb, pos + length, SEEK_SET);
466 }
467
468 static void get_tag(AVFormatContext *s, AVIOContext *pb, const char *key, int type, int length)
469 {
470     int buf_size = FFMAX(2*length, LEN_PRETTY_GUID) + 1;
471     char *buf = av_malloc(buf_size);
472     if (!buf)
473         return;
474
475     if (type == 0 && length == 4) {
476         snprintf(buf, buf_size, "%"PRIi32, avio_rl32(pb));
477     } else if (type == 1) {
478         avio_get_str16le(pb, length, buf, buf_size);
479         if (!strlen(buf)) {
480            av_free(buf);
481            return;
482         }
483     } else if (type == 3 && length == 4) {
484         strcpy(buf, avio_rl32(pb) ? "true" : "false");
485     } else if (type == 4 && length == 8) {
486         int64_t num = avio_rl64(pb);
487         if (!strcmp(key, "WM/EncodingTime") ||
488             !strcmp(key, "WM/MediaOriginalBroadcastDateTime"))
489             filetime_to_iso8601(buf, buf_size, num);
490         else if (!strcmp(key, "WM/WMRVEncodeTime") ||
491                  !strcmp(key, "WM/WMRVEndTime"))
492             crazytime_to_iso8601(buf, buf_size, num);
493         else if (!strcmp(key, "WM/WMRVExpirationDate"))
494             oledate_to_iso8601(buf, buf_size, num);
495         else if (!strcmp(key, "WM/WMRVBitrate"))
496             snprintf(buf, buf_size, "%f", av_int2dbl(num));
497         else
498             snprintf(buf, buf_size, "%"PRIi64, num);
499     } else if (type == 5 && length == 2) {
500         snprintf(buf, buf_size, "%"PRIi16, avio_rl16(pb));
501     } else if (type == 6 && length == 16) {
502         ff_asf_guid guid;
503         avio_read(pb, guid, 16);
504         snprintf(buf, buf_size, PRI_PRETTY_GUID, ARG_PRETTY_GUID(guid));
505     } else if (type == 2 && !strcmp(key, "WM/Picture")) {
506         get_attachment(s, pb, length);
507         av_freep(&buf);
508         return;
509     } else {
510         av_freep(&buf);
511         av_log(s, AV_LOG_WARNING, "unsupported metadata entry; key:%s, type:%d, length:0x%x\n", key, type, length);
512         avio_skip(pb, length);
513         return;
514     }
515
516     av_metadata_set2(&s->metadata, key, buf, 0);
517     av_freep(&buf);
518 }
519
520 /**
521  * Parse metadata entries
522  */
523 static void parse_legacy_attrib(AVFormatContext *s, AVIOContext *pb)
524 {
525     ff_asf_guid guid;
526     int length, type;
527     while(!url_feof(pb)) {
528         char key[1024];
529         ff_get_guid(pb, &guid);
530         type   = avio_rl32(pb);
531         length = avio_rl32(pb);
532         if (!length)
533             break;
534         if (ff_guidcmp(&guid, metadata_guid)) {
535             av_log(s, AV_LOG_WARNING, "unknown guid "FF_PRI_GUID", expected metadata_guid; "
536                    "remaining metadata entries ignored\n", FF_ARG_GUID(guid));
537             break;
538         }
539         avio_get_str16le(pb, INT_MAX, key, sizeof(key));
540         get_tag(s, pb, key, type, length);
541     }
542
543     ff_metadata_conv(&s->metadata, NULL, ff_asf_metadata_conv);
544 }
545
546 /**
547  * parse VIDEOINFOHEADER2 structure
548  * @return bytes consumed
549  */
550 static int parse_videoinfoheader2(AVFormatContext *s, AVStream *st)
551 {
552     WtvContext *wtv = s->priv_data;
553     AVIOContext *pb = wtv->pb;
554
555     avio_skip(pb, 72);  // picture aspect ratio is unreliable
556     ff_get_bmp_header(pb, st);
557
558     return 72 + 40;
559 }
560
561 /**
562  * Parse MPEG1WAVEFORMATEX extradata structure
563  */
564 static void parse_mpeg1waveformatex(AVStream *st)
565 {
566     /* fwHeadLayer */
567     switch (AV_RL16(st->codec->extradata)) {
568     case 0x0001 : st->codec->codec_id = CODEC_ID_MP1; break;
569     case 0x0002 : st->codec->codec_id = CODEC_ID_MP2; break;
570     case 0x0004 : st->codec->codec_id = CODEC_ID_MP3; break;
571     }
572
573     st->codec->bit_rate = AV_RL32(st->codec->extradata + 2); /* dwHeadBitrate */
574
575     /* dwHeadMode */
576     switch (AV_RL16(st->codec->extradata + 6)) {
577     case 1 : case 2 : case 4 : st->codec->channels = 2; break;
578     case 8 :                   st->codec->channels = 1; break;
579     }
580 }
581
582 /**
583  * Initialise stream
584  * @param st Stream to initialise, or NULL to create and initialise new stream
585  * @return NULL on error
586  */
587 static AVStream * new_stream(AVFormatContext *s, AVStream *st, int sid, int codec_type)
588 {
589     if (st) {
590         if (st->codec->extradata) {
591             av_freep(&st->codec->extradata);
592             st->codec->extradata_size = 0;
593         }
594     } else {
595         WtvStream *wst = av_mallocz(sizeof(WtvStream));
596         if (!wst)
597             return NULL;
598         st = av_new_stream(s, sid);
599         if (!st)
600             return NULL;
601         st->priv_data = wst;
602     }
603     st->codec->codec_type = codec_type;
604     st->need_parsing      = AVSTREAM_PARSE_FULL;
605     av_set_pts_info(st, 64, 1, 10000000);
606     return st;
607 }
608
609 /**
610  * parse Media Type structure and populate stream
611  * @param st         Stream, or NULL to create new stream
612  * @param mediatype  Mediatype GUID
613  * @param subtype    Subtype GUID
614  * @param formattype Format GUID
615  * @param size       Size of format buffer
616  * @return NULL on error
617  */
618 static AVStream * parse_media_type(AVFormatContext *s, AVStream *st, int sid,
619                                    ff_asf_guid mediatype, ff_asf_guid subtype,
620                                    ff_asf_guid formattype, int size)
621 {
622     WtvContext *wtv = s->priv_data;
623     AVIOContext *pb = wtv->pb;
624     if (!ff_guidcmp(subtype, mediasubtype_cpfilters_processed) &&
625         !ff_guidcmp(formattype, format_cpfilters_processed)) {
626         ff_asf_guid actual_subtype;
627         ff_asf_guid actual_formattype;
628
629         if (size < 32) {
630             av_log(s, AV_LOG_WARNING, "format buffer size underflow\n");
631             avio_skip(pb, size);
632             return NULL;
633         }
634
635         avio_skip(pb, size - 32);
636         ff_get_guid(pb, &actual_subtype);
637         ff_get_guid(pb, &actual_formattype);
638         avio_seek(pb, -size, SEEK_CUR);
639
640         st = parse_media_type(s, st, sid, mediatype, actual_subtype, actual_formattype, size - 32);
641         avio_skip(pb, 32);
642         return st;
643     } else if (!ff_guidcmp(mediatype, mediatype_audio)) {
644         st = new_stream(s, st, sid, AVMEDIA_TYPE_AUDIO);
645         if (!st)
646             return NULL;
647         if (!ff_guidcmp(formattype, format_waveformatex)) {
648             int ret = ff_get_wav_header(pb, st->codec, size);
649             if (ret < 0)
650                 return NULL;
651         } else {
652             if (ff_guidcmp(formattype, format_none))
653                 av_log(s, AV_LOG_WARNING, "unknown formattype:"FF_PRI_GUID"\n", FF_ARG_GUID(formattype));
654             avio_skip(pb, size);
655         }
656
657         if (!memcmp(subtype + 4, (const uint8_t[]){FF_MEDIASUBTYPE_BASE_GUID}, 12)) {
658             st->codec->codec_id = ff_wav_codec_get_id(AV_RL32(subtype), st->codec->bits_per_coded_sample);
659         } else if (!ff_guidcmp(subtype, mediasubtype_mpeg1payload)) {
660             if (st->codec->extradata && st->codec->extradata_size >= 22)
661                 parse_mpeg1waveformatex(st);
662             else
663                 av_log(s, AV_LOG_WARNING, "MPEG1WAVEFORMATEX underflow\n");
664         } else {
665             st->codec->codec_id = ff_codec_guid_get_id(ff_codec_wav_guids, subtype);
666             if (st->codec->codec_id == CODEC_ID_NONE)
667                 av_log(s, AV_LOG_WARNING, "unknown subtype:"FF_PRI_GUID"\n", FF_ARG_GUID(subtype));
668         }
669         return st;
670     } else if (!ff_guidcmp(mediatype, mediatype_video)) {
671         st = new_stream(s, st, sid, AVMEDIA_TYPE_VIDEO);
672         if (!st)
673             return NULL;
674         if (!ff_guidcmp(formattype, format_videoinfo2)) {
675             int consumed = parse_videoinfoheader2(s, st);
676             avio_skip(pb, FFMAX(size - consumed, 0));
677         } else if (!ff_guidcmp(formattype, format_mpeg2_video)) {
678             int consumed = parse_videoinfoheader2(s, st);
679             avio_skip(pb, FFMAX(size - consumed, 0));
680         } else {
681             if (ff_guidcmp(formattype, format_none))
682                 av_log(s, AV_LOG_WARNING, "unknown formattype:"FF_PRI_GUID"\n", FF_ARG_GUID(formattype));
683             avio_skip(pb, size);
684         }
685
686         if (!memcmp(subtype + 4, (const uint8_t[]){FF_MEDIASUBTYPE_BASE_GUID}, 12)) {
687             st->codec->codec_id = ff_codec_get_id(ff_codec_bmp_tags, AV_RL32(subtype));
688         } else {
689             st->codec->codec_id = ff_codec_guid_get_id(video_guids, subtype);
690         }
691         if (st->codec->codec_id == CODEC_ID_NONE)
692             av_log(s, AV_LOG_WARNING, "unknown subtype:"FF_PRI_GUID"\n", FF_ARG_GUID(subtype));
693         return st;
694     } else if (!ff_guidcmp(mediatype, mediatype_mpeg2_pes) &&
695                !ff_guidcmp(subtype, mediasubtype_dvb_subtitle)) {
696         st = new_stream(s, st, sid, AVMEDIA_TYPE_SUBTITLE);
697         if (!st)
698             return NULL;
699         if (ff_guidcmp(formattype, format_none))
700             av_log(s, AV_LOG_WARNING, "unknown formattype:"FF_PRI_GUID"\n", FF_ARG_GUID(formattype));
701         avio_skip(pb, size);
702         st->codec->codec_id = CODEC_ID_DVB_SUBTITLE;
703         return st;
704     } else if (!ff_guidcmp(mediatype, mediatype_mstvcaption) &&
705                (!ff_guidcmp(subtype, mediasubtype_teletext) || !ff_guidcmp(subtype, mediasubtype_dtvccdata))) {
706         st = new_stream(s, st, sid, AVMEDIA_TYPE_SUBTITLE);
707         if (!st)
708             return NULL;
709         if (ff_guidcmp(formattype, format_none))
710             av_log(s, AV_LOG_WARNING, "unknown formattype:"FF_PRI_GUID"\n", FF_ARG_GUID(formattype));
711         avio_skip(pb, size);
712         st->codec->codec_id   = CODEC_ID_DVB_TELETEXT;
713         return st;
714     } else if (!ff_guidcmp(mediatype, mediatype_mpeg2_sections) &&
715                !ff_guidcmp(subtype, mediasubtype_mpeg2_sections)) {
716         if (ff_guidcmp(formattype, format_none))
717             av_log(s, AV_LOG_WARNING, "unknown formattype:"FF_PRI_GUID"\n", FF_ARG_GUID(formattype));
718         avio_skip(pb, size);
719         return NULL;
720     }
721
722     av_log(s, AV_LOG_WARNING, "unknown media type, mediatype:"FF_PRI_GUID
723                               ", subtype:"FF_PRI_GUID", formattype:"FF_PRI_GUID"\n",
724                               FF_ARG_GUID(mediatype), FF_ARG_GUID(subtype), FF_ARG_GUID(formattype));
725     avio_skip(pb, size);
726     return NULL;
727 }
728
729 enum {
730     SEEK_TO_DATA = 0,
731     SEEK_TO_PTS,
732 };
733
734 /**
735  * Parse WTV chunks
736  * @param mode SEEK_TO_DATA or SEEK_TO_PTS
737  * @param seekts timestamp
738  * @param[out] len Length of data chunk
739  * @return stream index of data chunk, or <0 on error
740  */
741 static int parse_chunks(AVFormatContext *s, int mode, int64_t seekts, int *len_ptr)
742 {
743     WtvContext *wtv = s->priv_data;
744     AVIOContext *pb = wtv->pb;
745     while (!url_feof(pb)) {
746         ff_asf_guid g;
747         int len, sid, consumed;
748
749         ff_get_guid(pb, &g);
750         len = avio_rl32(pb);
751         if (len < 32)
752             break;
753         sid = avio_rl32(pb) & 0x7FFF;
754         avio_skip(pb, 8);
755         consumed = 32;
756
757         if (!ff_guidcmp(g, stream_guid)) {
758             if (ff_find_stream_index(s, sid) < 0) {
759                 ff_asf_guid mediatype, subtype, formattype;
760                 int size;
761                 avio_skip(pb, 28);
762                 ff_get_guid(pb, &mediatype);
763                 ff_get_guid(pb, &subtype);
764                 avio_skip(pb, 12);
765                 ff_get_guid(pb, &formattype);
766                 size = avio_rl32(pb);
767                 parse_media_type(s, 0, sid, mediatype, subtype, formattype, size);
768                 consumed += 92 + size;
769             }
770         } else if (!ff_guidcmp(g, stream2_guid)) {
771             int stream_index = ff_find_stream_index(s, sid);
772             if (stream_index >= 0 && !((WtvStream*)s->streams[stream_index]->priv_data)->seen_data) {
773                 ff_asf_guid mediatype, subtype, formattype;
774                 int size;
775                 avio_skip(pb, 12);
776                 ff_get_guid(pb, &mediatype);
777                 ff_get_guid(pb, &subtype);
778                 avio_skip(pb, 12);
779                 ff_get_guid(pb, &formattype);
780                 size = avio_rl32(pb);
781                 parse_media_type(s, s->streams[stream_index], sid, mediatype, subtype, formattype, size);
782                 consumed += 76 + size;
783             }
784         } else if (!ff_guidcmp(g, EVENTID_AudioDescriptorSpanningEvent) ||
785                    !ff_guidcmp(g, EVENTID_CtxADescriptorSpanningEvent) ||
786                    !ff_guidcmp(g, EVENTID_CSDescriptorSpanningEvent) ||
787                    !ff_guidcmp(g, EVENTID_StreamIDSpanningEvent) ||
788                    !ff_guidcmp(g, EVENTID_SubtitleSpanningEvent) ||
789                    !ff_guidcmp(g, EVENTID_TeletextSpanningEvent)) {
790             int stream_index = ff_find_stream_index(s, sid);
791             if (stream_index >= 0) {
792                 AVStream *st = s->streams[stream_index];
793                 uint8_t buf[258];
794                 const uint8_t *pbuf = buf;
795                 int buf_size;
796
797                 avio_skip(pb, 8);
798                 consumed += 8;
799                 if (!ff_guidcmp(g, EVENTID_CtxADescriptorSpanningEvent) ||
800                     !ff_guidcmp(g, EVENTID_CSDescriptorSpanningEvent)) {
801                     avio_skip(pb, 6);
802                     consumed += 6;
803                 }
804
805                 buf_size = FFMIN(len - consumed, sizeof(buf));
806                 avio_read(pb, buf, buf_size);
807                 consumed += buf_size;
808                 ff_parse_mpeg2_descriptor(s, st, 0, &pbuf, buf + buf_size, 0, 0, 0, 0);
809             }
810         } else if (!ff_guidcmp(g, EVENTID_AudioTypeSpanningEvent)) {
811             int stream_index = ff_find_stream_index(s, sid);
812             if (stream_index >= 0) {
813                 AVStream *st = s->streams[stream_index];
814                 int audio_type;
815                 avio_skip(pb, 8);
816                 audio_type = avio_r8(pb);
817                 if (audio_type == 2)
818                     st->disposition |= AV_DISPOSITION_HEARING_IMPAIRED;
819                 else if (audio_type == 3)
820                     st->disposition |= AV_DISPOSITION_VISUAL_IMPAIRED;
821                 consumed += 9;
822             }
823         } else if (!ff_guidcmp(g, EVENTID_DVBScramblingControlSpanningEvent)) {
824             int stream_index = ff_find_stream_index(s, sid);
825             if (stream_index >= 0) {
826                 avio_skip(pb, 12);
827                 if (avio_rl32(pb))
828                     av_log(s, AV_LOG_WARNING, "DVB scrambled stream detected (st:%d), decoding will likely fail\n", stream_index);
829                 consumed += 16;
830             }
831         } else if (!ff_guidcmp(g, EVENTID_LanguageSpanningEvent)) {
832             int stream_index = ff_find_stream_index(s, sid);
833             if (stream_index >= 0) {
834                 AVStream *st = s->streams[stream_index];
835                 uint8_t language[4];
836                 avio_skip(pb, 12);
837                 avio_read(pb, language, 3);
838                 if (language[0]) {
839                     language[3] = 0;
840                     av_metadata_set2(&st->metadata, "language", language, 0);
841                     if (!strcmp(language, "nar") || !strcmp(language, "NAR"))
842                         st->disposition |= AV_DISPOSITION_VISUAL_IMPAIRED;
843                 }
844                 consumed += 15;
845             }
846         } else if (!ff_guidcmp(g, timestamp_guid)) {
847             int stream_index = ff_find_stream_index(s, sid);
848             if (stream_index >= 0) {
849                 avio_skip(pb, 8);
850                 wtv->pts = avio_rl64(pb);
851                 consumed += 16;
852                 if (wtv->pts == -1)
853                     wtv->pts = AV_NOPTS_VALUE;
854                 else {
855                     wtv->last_valid_pts = wtv->pts;
856                     if (wtv->epoch == AV_NOPTS_VALUE || wtv->pts < wtv->epoch)
857                         wtv->epoch = wtv->pts;
858                 if (mode == SEEK_TO_PTS && wtv->pts >= seekts) {
859 #define WTV_PAD8(x) (((x) + 7) & ~7)
860                     avio_skip(pb, WTV_PAD8(len) - consumed);
861                     return 0;
862                 }
863                 }
864             }
865         } else if (!ff_guidcmp(g, data_guid)) {
866             int stream_index = ff_find_stream_index(s, sid);
867             if (mode == SEEK_TO_DATA && stream_index >= 0 && len > 32) {
868                 WtvStream *wst = s->streams[stream_index]->priv_data;
869                 wst->seen_data = 1;
870                 if (len_ptr) {
871                     *len_ptr = len;
872                 }
873                 return stream_index;
874             }
875         } else if (
876             !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}) ||
877             !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}) ||
878             !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}) ||
879             !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}) ||
880             !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}) ||
881             !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}) ||
882             !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}) ||
883             !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}) ||
884             !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}) ||
885             !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}) ||
886             !ff_guidcmp(g, (const ff_asf_guid){0x1E,0xBE,0xC3,0xC5,0x43,0x92,0xDC,0x11,0x85,0xE5,0x00,0x12,0x3F,0x6F,0x73,0xB9}) ||
887             !ff_guidcmp(g, (const ff_asf_guid){0x3B,0x86,0xA2,0xB1,0xEB,0x1E,0xC3,0x44,0x8C,0x88,0x1C,0xA3,0xFF,0xE3,0xE7,0x6A}) ||
888             !ff_guidcmp(g, (const ff_asf_guid){0x4E,0x7F,0x4C,0x5B,0xC4,0xD0,0x38,0x4B,0xA8,0x3E,0x21,0x7F,0x7B,0xBF,0x52,0xE7}) ||
889             !ff_guidcmp(g, (const ff_asf_guid){0x63,0x36,0xEB,0xFE,0xA1,0x7E,0xD9,0x11,0x83,0x08,0x00,0x07,0xE9,0x5E,0xAD,0x8D}) ||
890             !ff_guidcmp(g, (const ff_asf_guid){0x70,0xE9,0xF1,0xF8,0x89,0xA4,0x4C,0x4D,0x83,0x73,0xB8,0x12,0xE0,0xD5,0xF8,0x1E}) ||
891             !ff_guidcmp(g, (const ff_asf_guid){0x96,0xC3,0xD2,0xC2,0x7E,0x9A,0xDA,0x11,0x8B,0xF7,0x00,0x07,0xE9,0x5E,0xAD,0x8D}) ||
892             !ff_guidcmp(g, (const ff_asf_guid){0x97,0xC3,0xD2,0xC2,0x7E,0x9A,0xDA,0x11,0x8B,0xF7,0x00,0x07,0xE9,0x5E,0xAD,0x8D}) ||
893             !ff_guidcmp(g, (const ff_asf_guid){0xA1,0xC3,0xD2,0xC2,0x7E,0x9A,0xDA,0x11,0x8B,0xF7,0x00,0x07,0xE9,0x5E,0xAD,0x8D})) {
894             //ignore known guids
895         } else
896             av_log(s, AV_LOG_WARNING, "unsupported chunk:"FF_PRI_GUID"\n", FF_ARG_GUID(g));
897
898         avio_skip(pb, WTV_PAD8(len) - consumed);
899     }
900     return AVERROR_EOF;
901 }
902
903 /* declare utf16le strings */
904 #define _ , 0,
905 static const uint8_t timeline_le16[] =
906     {'t'_'i'_'m'_'e'_'l'_'i'_'n'_'e', 0};
907 static const uint8_t table_0_entries_legacy_attrib_le16[] =
908     {'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};
909 static const uint8_t table_0_entries_time_le16[] =
910     {'t'_'a'_'b'_'l'_'e'_'.'_'0'_'.'_'e'_'n'_'t'_'r'_'i'_'e'_'s'_'.'_'t'_'i'_'m'_'e', 0};
911 static const uint8_t timeline_table_0_entries_Events_le16[] =
912     {'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};
913 #undef _
914
915 static int read_header(AVFormatContext *s, AVFormatParameters *ap)
916 {
917     WtvContext *wtv = s->priv_data;
918     int root_sector, root_size;
919     uint8_t root[WTV_SECTOR_SIZE];
920     AVIOContext *pb;
921     int64_t timeline_pos;
922     int ret;
923
924     wtv->epoch          =
925     wtv->pts            =
926     wtv->last_valid_pts = AV_NOPTS_VALUE;
927
928     /* read root directory sector */
929     avio_skip(s->pb, 0x30);
930     root_size = avio_rl32(s->pb);
931     if (root_size > sizeof(root)) {
932         av_log(s, AV_LOG_ERROR, "root directory size exceeds sector size\n");
933         return AVERROR_INVALIDDATA;
934     }
935     avio_skip(s->pb, 4);
936     root_sector = avio_rl32(s->pb);
937
938     avio_seek(s->pb, root_sector << WTV_SECTOR_BITS, SEEK_SET);
939     root_size = avio_read(s->pb, root, root_size);
940     if (root_size < 0)
941         return AVERROR_INVALIDDATA;
942
943     /* parse chunks up until first data chunk */
944     wtv->pb = wtvfile_open(s, root, root_size, timeline_le16);
945     if (!wtv->pb) {
946         av_log(s, AV_LOG_ERROR, "timeline data missing\n");
947         return AVERROR_INVALIDDATA;
948     }
949
950     ret = parse_chunks(s, SEEK_TO_DATA, 0, 0);
951     if (ret < 0)
952         return ret;
953     avio_seek(wtv->pb, -32, SEEK_CUR);
954
955     timeline_pos = avio_tell(s->pb); // save before opening another file
956
957     /* read metadata */
958     pb = wtvfile_open(s, root, root_size, table_0_entries_legacy_attrib_le16);
959     if (pb) {
960         parse_legacy_attrib(s, pb);
961         wtvfile_close(pb);
962     }
963
964     /* read seek index */
965     if (s->nb_streams) {
966         AVStream *st = s->streams[0];
967         pb = wtvfile_open(s, root, root_size, table_0_entries_time_le16);
968         if (pb) {
969             while(1) {
970                 uint64_t timestamp = avio_rl64(pb);
971                 uint64_t frame_nb  = avio_rl64(pb);
972                 if (url_feof(pb))
973                     break;
974                 ff_add_index_entry(&wtv->index_entries, &wtv->nb_index_entries, &wtv->index_entries_allocated_size,
975                                    0, timestamp, frame_nb, 0, AVINDEX_KEYFRAME);
976             }
977             wtvfile_close(pb);
978
979             if (wtv->nb_index_entries) {
980                 pb = wtvfile_open(s, root, root_size, timeline_table_0_entries_Events_le16);
981                 if (pb) {
982                     int i;
983                     while (1) {
984                         uint64_t frame_nb = avio_rl64(pb);
985                         uint64_t position = avio_rl64(pb);
986                         if (url_feof(pb))
987                             break;
988                         for (i = wtv->nb_index_entries - 1; i >= 0; i--) {
989                             AVIndexEntry *e = wtv->index_entries + i;
990                             if (frame_nb > e->size)
991                                 break;
992                             if (position > e->pos)
993                                 e->pos = position;
994                         }
995                     }
996                     wtvfile_close(pb);
997                     st->duration = wtv->index_entries[wtv->nb_index_entries - 1].timestamp;
998                 }
999             }
1000         }
1001     }
1002
1003     avio_seek(s->pb, timeline_pos, SEEK_SET);
1004     return 0;
1005 }
1006
1007 static int read_packet(AVFormatContext *s, AVPacket *pkt)
1008 {
1009     WtvContext *wtv = s->priv_data;
1010     AVIOContext *pb = wtv->pb;
1011     int stream_index, len, ret;
1012
1013     stream_index = parse_chunks(s, SEEK_TO_DATA, 0, &len);
1014     if (stream_index < 0)
1015         return stream_index;
1016
1017     ret = av_get_packet(pb, pkt, len - 32);
1018     if (ret < 0)
1019         return ret;
1020     pkt->stream_index = stream_index;
1021     pkt->pts          = wtv->pts;
1022     avio_skip(pb, WTV_PAD8(len) - len);
1023     return 0;
1024 }
1025
1026 static int read_seek(AVFormatContext *s, int stream_index,
1027                      int64_t ts, int flags)
1028 {
1029     WtvContext *wtv = s->priv_data;
1030     AVIOContext *pb = wtv->pb;
1031     AVStream *st = s->streams[0];
1032     int64_t ts_relative;
1033     int i;
1034
1035     if ((flags & AVSEEK_FLAG_FRAME) || (flags & AVSEEK_FLAG_BYTE))
1036         return AVERROR(ENOSYS);
1037
1038     /* timestamp adjustment is required because wtv->pts values are absolute,
1039      * whereas AVIndexEntry->timestamp values are relative to epoch. */
1040     ts_relative = ts;
1041     if (wtv->epoch != AV_NOPTS_VALUE)
1042         ts_relative -= wtv->epoch;
1043
1044     i = ff_index_search_timestamp(wtv->index_entries, wtv->nb_index_entries, ts_relative, flags);
1045     if (i < 0) {
1046         if (wtv->last_valid_pts == AV_NOPTS_VALUE || ts < wtv->last_valid_pts)
1047             avio_seek(pb, 0, SEEK_SET);
1048         else if (st->duration != AV_NOPTS_VALUE && ts_relative > st->duration && wtv->nb_index_entries)
1049             avio_seek(pb, wtv->index_entries[wtv->nb_index_entries - 1].pos, SEEK_SET);
1050         if (parse_chunks(s, SEEK_TO_PTS, ts, 0) < 0)
1051             return AVERROR(ERANGE);
1052         return 0;
1053     }
1054     wtv->pts = wtv->index_entries[i].timestamp;
1055     if (wtv->epoch != AV_NOPTS_VALUE)
1056         wtv->pts += wtv->epoch;
1057     wtv->last_valid_pts = wtv->pts;
1058     avio_seek(pb, wtv->index_entries[i].pos, SEEK_SET);
1059     return 0;
1060 }
1061
1062 static int read_close(AVFormatContext *s)
1063 {
1064     WtvContext *wtv = s->priv_data;
1065     wtvfile_close(wtv->pb);
1066     return 0;
1067 }
1068
1069 AVInputFormat ff_wtv_demuxer = {
1070     .name           = "wtv",
1071     .long_name      = NULL_IF_CONFIG_SMALL("Windows Television (WTV)"),
1072     .priv_data_size = sizeof(WtvContext),
1073     .read_probe     = read_probe,
1074     .read_header    = read_header,
1075     .read_packet    = read_packet,
1076     .read_seek      = read_seek,
1077     .read_close     = read_close,
1078     .flags          = AVFMT_SHOW_IDS,
1079 };