wtv: Drop some casts that now are unnecessary
[ffmpeg.git] / libavformat / wtv.c
1 /*
2  * Windows Television (WTV) demuxer
3  * Copyright (c) 2010-2011 Peter Ross <pross@xvid.org>
4  *
5  * This file is part of Libav.
6  *
7  * Libav is free software; you can redistribute it and/or
8  * modify it under the terms of the GNU Lesser General Public
9  * License as published by the Free Software Foundation; either
10  * version 2.1 of the License, or (at your option) any later version.
11  *
12  * Libav is distributed in the hope that it will be useful,
13  * but WITHOUT ANY WARRANTY; without even the implied warranty of
14  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
15  * Lesser General Public License for more details.
16  *
17  * You should have received a copy of the GNU Lesser General Public
18  * License along with Libav; if not, write to the Free Software
19  * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA
20  */
21
22 /**
23  * @file
24  * Windows Television (WTV) demuxer
25  * @author Peter Ross <pross@xvid.org>
26  */
27
28 #include "libavutil/channel_layout.h"
29 #include "libavutil/intreadwrite.h"
30 #include "libavutil/intfloat.h"
31 #include "libavutil/dict.h"
32 #include "avformat.h"
33 #include "internal.h"
34 #include "riff.h"
35 #include "asf.h"
36 #include "mpegts.h"
37
38 /* Macros for formating GUIDs */
39 #define PRI_PRETTY_GUID \
40     "%08x-%04x-%04x-%02x%02x%02x%02x%02x%02x%02x%02x"
41 #define ARG_PRETTY_GUID(g) \
42     AV_RL32(g),AV_RL16(g+4),AV_RL16(g+6),g[8],g[9],g[10],g[11],g[12],g[13],g[14],g[15]
43 #define LEN_PRETTY_GUID 34
44
45 /*
46  *
47  * File system routines
48  *
49  */
50
51 #define WTV_SECTOR_BITS    INT64_C(12)
52 #define WTV_SECTOR_SIZE    (1 << WTV_SECTOR_BITS)
53 #define WTV_BIGSECTOR_BITS 18
54
55 typedef struct {
56     AVIOContext *pb_filesystem;  /** file system (AVFormatContext->pb) */
57
58     int sector_bits;     /** sector shift bits; used to convert sector number into pb_filesystem offset */
59     uint32_t *sectors;   /** file allocation table */
60     int nb_sectors;      /** number of sectors */
61
62     int error;
63     int64_t position;
64     int64_t length;
65 } WtvFile;
66
67 /**
68  * @return bytes read, 0 on end of file, or <0 on error
69  */
70 static int wtvfile_read_packet(void *opaque, uint8_t *buf, int buf_size)
71 {
72     WtvFile *wf = opaque;
73     AVIOContext *pb = wf->pb_filesystem;
74     int nread = 0;
75
76     if (wf->error || pb->error)
77         return -1;
78     if (wf->position >= wf->length || pb->eof_reached)
79         return 0;
80
81     buf_size = FFMIN(buf_size, wf->length - wf->position);
82     while(nread < buf_size) {
83         int n;
84         int remaining_in_sector = (1 << wf->sector_bits) - (wf->position & ((1 << wf->sector_bits) - 1));
85         int read_request        = FFMIN(buf_size - nread, remaining_in_sector);
86
87         n = avio_read(pb, buf, read_request);
88         if (n <= 0)
89             break;
90         nread += n;
91         buf += n;
92         wf->position += n;
93         if (n == remaining_in_sector) {
94             int i = wf->position >> wf->sector_bits;
95             if (i >= wf->nb_sectors ||
96                 (wf->sectors[i] != wf->sectors[i - 1] + (1 << (wf->sector_bits - WTV_SECTOR_BITS)) &&
97                 avio_seek(pb, wf->sectors[i] << WTV_SECTOR_BITS, SEEK_SET) < 0)) {
98                 wf->error = 1;
99                 break;
100             }
101         }
102     }
103     return nread;
104 }
105
106 /**
107  * @return position (or file length)
108  */
109 static int64_t wtvfile_seek(void *opaque, int64_t offset, int whence)
110 {
111     WtvFile *wf = opaque;
112     AVIOContext *pb = wf->pb_filesystem;
113
114     if (whence == AVSEEK_SIZE)
115         return wf->length;
116     else if (whence == SEEK_CUR)
117         offset = wf->position + offset;
118     else if (whence == SEEK_END)
119         offset = wf->length;
120
121     wf->error = offset < 0 || offset >= wf->length ||
122                 avio_seek(pb, (wf->sectors[offset >> wf->sector_bits] << WTV_SECTOR_BITS)
123                               + (offset & ((1 << wf->sector_bits) - 1)), SEEK_SET) < 0;
124     wf->position = offset;
125     return offset;
126 }
127
128 /**
129  * read non-zero integers (le32) from input stream
130  * @param pb
131  * @param[out] data destination
132  * @param     count maximum number of integers to read
133  * @return    total number of integers read
134  */
135 static int read_ints(AVIOContext *pb, uint32_t *data, int count)
136 {
137     int i, total = 0;
138     for (i = 0; i < count; i++) {
139         if ((data[total] = avio_rl32(pb)))
140            total++;
141     }
142     return total;
143 }
144
145 /**
146  * Open file
147  * @param first_sector  First sector
148  * @param length        Length of file (bytes)
149  * @param depth         File allocation table depth
150  * @return NULL on error
151  */
152 static AVIOContext * wtvfile_open_sector(int first_sector, uint64_t length, int depth, AVFormatContext *s)
153 {
154     AVIOContext *pb;
155     WtvFile *wf;
156     uint8_t *buffer;
157
158     if (avio_seek(s->pb, first_sector << WTV_SECTOR_BITS, SEEK_SET) < 0)
159         return NULL;
160
161     wf = av_mallocz(sizeof(WtvFile));
162     if (!wf)
163         return NULL;
164
165     if (depth == 0) {
166         wf->sectors = av_malloc(sizeof(uint32_t));
167         if (!wf->sectors) {
168             av_free(wf);
169             return NULL;
170         }
171         wf->sectors[0]  = first_sector;
172         wf->nb_sectors  = 1;
173         wf->sector_bits = WTV_SECTOR_BITS;
174     } else if (depth == 1) {
175         wf->sectors = av_malloc(WTV_SECTOR_SIZE);
176         if (!wf->sectors) {
177             av_free(wf);
178             return NULL;
179         }
180         wf->nb_sectors  = read_ints(s->pb, wf->sectors, WTV_SECTOR_SIZE / 4);
181         wf->sector_bits = length & (1ULL<<63) ? WTV_SECTOR_BITS : WTV_BIGSECTOR_BITS;
182     } else if (depth == 2) {
183         uint32_t sectors1[WTV_SECTOR_SIZE / 4];
184         int nb_sectors1 = read_ints(s->pb, sectors1, WTV_SECTOR_SIZE / 4);
185         int i;
186
187         wf->sectors = av_malloc(nb_sectors1 << WTV_SECTOR_BITS);
188         if (!wf->sectors) {
189             av_free(wf);
190             return NULL;
191         }
192         wf->nb_sectors = 0;
193         for (i = 0; i < nb_sectors1; i++) {
194             if (avio_seek(s->pb, sectors1[i] << WTV_SECTOR_BITS, SEEK_SET) < 0)
195                 break;
196             wf->nb_sectors += read_ints(s->pb, wf->sectors + i * WTV_SECTOR_SIZE / 4, WTV_SECTOR_SIZE / 4);
197         }
198         wf->sector_bits = length & (1ULL<<63) ? WTV_SECTOR_BITS : WTV_BIGSECTOR_BITS;
199     } else {
200         av_log(s, AV_LOG_ERROR, "unsupported file allocation table depth (0x%x)\n", depth);
201         av_free(wf);
202         return NULL;
203     }
204
205     if (!wf->nb_sectors) {
206         av_free(wf->sectors);
207         av_free(wf);
208         return NULL;
209     }
210
211     /* check length */
212     length &= 0xFFFFFFFFFFFF;
213     if (length > ((int64_t)wf->nb_sectors << wf->sector_bits)) {
214         av_log(s, AV_LOG_WARNING, "reported file length (0x%"PRIx64") exceeds number of available sectors (0x%"PRIx64")\n", length, (int64_t)wf->nb_sectors << wf->sector_bits);
215         length = (int64_t)wf->nb_sectors <<  wf->sector_bits;
216     }
217     wf->length = length;
218
219     /* seek to initial sector */
220     wf->position = 0;
221     if (avio_seek(s->pb, wf->sectors[0] << WTV_SECTOR_BITS, SEEK_SET) < 0) {
222         av_free(wf->sectors);
223         av_free(wf);
224         return NULL;
225     }
226
227     wf->pb_filesystem = s->pb;
228     buffer = av_malloc(1 << wf->sector_bits);
229     if (!buffer) {
230         av_free(wf->sectors);
231         av_free(wf);
232         return NULL;
233     }
234
235     pb = avio_alloc_context(buffer, 1 << wf->sector_bits, 0, wf,
236                            wtvfile_read_packet, NULL, wtvfile_seek);
237     if (!pb) {
238         av_free(buffer);
239         av_free(wf->sectors);
240         av_free(wf);
241     }
242     return pb;
243 }
244
245 static const ff_asf_guid dir_entry_guid =
246     {0x92,0xB7,0x74,0x91,0x59,0x70,0x70,0x44,0x88,0xDF,0x06,0x3B,0x82,0xCC,0x21,0x3D};
247
248 /**
249  * Open file using filename
250  * @param[in]  buf       directory buffer
251  * @param      buf_size  directory buffer size
252  * @param[in]  filename
253  * @param      filename_size size of filename
254  * @return NULL on error
255  */
256 static AVIOContext * wtvfile_open2(AVFormatContext *s, const uint8_t *buf, int buf_size, const uint8_t *filename, int filename_size)
257 {
258     const uint8_t *buf_end = buf + buf_size;
259
260     while(buf + 48 <= buf_end) {
261         int dir_length, name_size, first_sector, depth;
262         uint64_t file_length;
263         const uint8_t *name;
264         if (ff_guidcmp(buf, dir_entry_guid)) {
265             av_log(s, AV_LOG_ERROR, "unknown guid "FF_PRI_GUID", expected dir_entry_guid; "
266                    "remaining directory entries ignored\n", FF_ARG_GUID(buf));
267             break;
268         }
269         dir_length  = AV_RL16(buf + 16);
270         file_length = AV_RL64(buf + 24);
271         name_size   = 2 * AV_RL32(buf + 32);
272         if (buf + 48 + name_size > buf_end) {
273             av_log(s, AV_LOG_ERROR, "filename exceeds buffer size; remaining directory entries ignored\n");
274             break;
275         }
276         first_sector = AV_RL32(buf + 40 + name_size);
277         depth        = AV_RL32(buf + 44 + name_size);
278
279         /* compare file name; test optional null terminator */
280         name = buf + 40;
281         if (name_size >= filename_size &&
282             !memcmp(name, filename, filename_size) &&
283             (name_size < filename_size + 2 || !AV_RN16(name + filename_size)))
284             return wtvfile_open_sector(first_sector, file_length, depth, s);
285
286         buf += dir_length;
287     }
288     return 0;
289 }
290
291 #define wtvfile_open(s, buf, buf_size, filename) \
292     wtvfile_open2(s, buf, buf_size, filename, sizeof(filename))
293
294 /**
295  * Close file opened with wtvfile_open_sector(), or wtv_open()
296  */
297 static void wtvfile_close(AVIOContext *pb)
298 {
299     WtvFile *wf = pb->opaque;
300     av_free(wf->sectors);
301     av_free(wf);
302     av_free(pb->buffer);
303     av_free(pb);
304 }
305
306 /*
307  *
308  * Main demuxer
309  *
310  */
311
312 typedef struct {
313     int seen_data;
314 } WtvStream;
315
316 typedef struct {
317     AVIOContext *pb;       /** timeline file */
318     int64_t epoch;
319     int64_t pts;             /** pts for next data chunk */
320     int64_t last_valid_pts;  /** latest valid pts, used for interative seeking */
321
322     /* maintain private seek index, as the AVIndexEntry->pos is relative to the
323        start of the 'timeline' file, not the file system (AVFormatContext->pb) */
324     AVIndexEntry *index_entries;
325     int nb_index_entries;
326     unsigned int index_entries_allocated_size;
327 } WtvContext;
328
329 /* WTV GUIDs */
330 static const ff_asf_guid wtv_guid =
331     {0xB7,0xD8,0x00,0x20,0x37,0x49,0xDA,0x11,0xA6,0x4E,0x00,0x07,0xE9,0x5E,0xAD,0x8D};
332 static const ff_asf_guid metadata_guid =
333     {0x5A,0xFE,0xD7,0x6D,0xC8,0x1D,0x8F,0x4A,0x99,0x22,0xFA,0xB1,0x1C,0x38,0x14,0x53};
334 static const ff_asf_guid timestamp_guid =
335     {0x5B,0x05,0xE6,0x1B,0x97,0xA9,0x49,0x43,0x88,0x17,0x1A,0x65,0x5A,0x29,0x8A,0x97};
336 static const ff_asf_guid data_guid =
337     {0x95,0xC3,0xD2,0xC2,0x7E,0x9A,0xDA,0x11,0x8B,0xF7,0x00,0x07,0xE9,0x5E,0xAD,0x8D};
338 static const ff_asf_guid stream_guid =
339     {0xED,0xA4,0x13,0x23,0x2D,0xBF,0x4F,0x45,0xAD,0x8A,0xD9,0x5B,0xA7,0xF9,0x1F,0xEE};
340 static const ff_asf_guid stream2_guid =
341     {0xA2,0xC3,0xD2,0xC2,0x7E,0x9A,0xDA,0x11,0x8B,0xF7,0x00,0x07,0xE9,0x5E,0xAD,0x8D};
342 static const ff_asf_guid EVENTID_SubtitleSpanningEvent =
343     {0x48,0xC0,0xCE,0x5D,0xB9,0xD0,0x63,0x41,0x87,0x2C,0x4F,0x32,0x22,0x3B,0xE8,0x8A};
344 static const ff_asf_guid EVENTID_LanguageSpanningEvent =
345     {0x6D,0x66,0x92,0xE2,0x02,0x9C,0x8D,0x44,0xAA,0x8D,0x78,0x1A,0x93,0xFD,0xC3,0x95};
346 static const ff_asf_guid EVENTID_AudioDescriptorSpanningEvent =
347     {0x1C,0xD4,0x7B,0x10,0xDA,0xA6,0x91,0x46,0x83,0x69,0x11,0xB2,0xCD,0xAA,0x28,0x8E};
348 static const ff_asf_guid EVENTID_CtxADescriptorSpanningEvent =
349     {0xE6,0xA2,0xB4,0x3A,0x47,0x42,0x34,0x4B,0x89,0x6C,0x30,0xAF,0xA5,0xD2,0x1C,0x24};
350 static const ff_asf_guid EVENTID_CSDescriptorSpanningEvent =
351     {0xD9,0x79,0xE7,0xEf,0xF0,0x97,0x86,0x47,0x80,0x0D,0x95,0xCF,0x50,0x5D,0xDC,0x66};
352 static const ff_asf_guid EVENTID_DVBScramblingControlSpanningEvent =
353     {0xC4,0xE1,0xD4,0x4B,0xA1,0x90,0x09,0x41,0x82,0x36,0x27,0xF0,0x0E,0x7D,0xCC,0x5B};
354 static const ff_asf_guid EVENTID_StreamIDSpanningEvent =
355     {0x68,0xAB,0xF1,0xCA,0x53,0xE1,0x41,0x4D,0xA6,0xB3,0xA7,0xC9,0x98,0xDB,0x75,0xEE};
356 static const ff_asf_guid EVENTID_TeletextSpanningEvent =
357     {0x50,0xD9,0x99,0x95,0x33,0x5F,0x17,0x46,0xAF,0x7C,0x1E,0x54,0xB5,0x10,0xDA,0xA3};
358 static const ff_asf_guid EVENTID_AudioTypeSpanningEvent =
359     {0xBE,0xBF,0x1C,0x50,0x49,0xB8,0xCE,0x42,0x9B,0xE9,0x3D,0xB8,0x69,0xFB,0x82,0xB3};
360
361 /* Windows media GUIDs */
362
363 /* Media types */
364 static const ff_asf_guid mediatype_audio =
365     {'a','u','d','s',FF_MEDIASUBTYPE_BASE_GUID};
366 static const ff_asf_guid mediatype_video =
367     {'v','i','d','s',FF_MEDIASUBTYPE_BASE_GUID};
368 static const ff_asf_guid mediasubtype_mpeg1payload =
369     {0x81,0xEB,0x36,0xE4,0x4F,0x52,0xCE,0x11,0x9F,0x53,0x00,0x20,0xAF,0x0B,0xA7,0x70};
370 static const ff_asf_guid mediatype_mpeg2_sections =
371     {0x6C,0x17,0x5F,0x45,0x06,0x4B,0xCE,0x47,0x9A,0xEF,0x8C,0xAE,0xF7,0x3D,0xF7,0xB5};
372 static const ff_asf_guid mediatype_mpeg2_pes =
373     {0x20,0x80,0x6D,0xE0,0x46,0xDB,0xCF,0x11,0xB4,0xD1,0x00,0x80,0x5F,0x6C,0xBB,0xEA};
374 static const ff_asf_guid mediatype_mstvcaption =
375     {0x89,0x8A,0x8B,0xB8,0x49,0xB0,0x80,0x4C,0xAD,0xCF,0x58,0x98,0x98,0x5E,0x22,0xC1};
376
377 /* Media subtypes */
378 static const ff_asf_guid mediasubtype_cpfilters_processed =
379     {0x28,0xBD,0xAD,0x46,0xD0,0x6F,0x96,0x47,0x93,0xB2,0x15,0x5C,0x51,0xDC,0x04,0x8D};
380 static const ff_asf_guid mediasubtype_dvb_subtitle =
381     {0xC3,0xCB,0xFF,0x34,0xB3,0xD5,0x71,0x41,0x90,0x02,0xD4,0xC6,0x03,0x01,0x69,0x7F};
382 static const ff_asf_guid mediasubtype_teletext =
383     {0xE3,0x76,0x2A,0xF7,0x0A,0xEB,0xD0,0x11,0xAC,0xE4,0x00,0x00,0xC0,0xCC,0x16,0xBA};
384 static const ff_asf_guid mediasubtype_dtvccdata =
385     {0xAA,0xDD,0x2A,0xF5,0xF0,0x36,0xF5,0x43,0x95,0xEA,0x6D,0x86,0x64,0x84,0x26,0x2A};
386 static const ff_asf_guid mediasubtype_mpeg2_sections =
387     {0x79,0x85,0x9F,0x4A,0xF8,0x6B,0x92,0x43,0x8A,0x6D,0xD2,0xDD,0x09,0xFA,0x78,0x61};
388
389 /* Formats */
390 static const ff_asf_guid format_cpfilters_processed =
391     {0x6F,0xB3,0x39,0x67,0x5F,0x1D,0xC2,0x4A,0x81,0x92,0x28,0xBB,0x0E,0x73,0xD1,0x6A};
392 static const ff_asf_guid format_waveformatex =
393     {0x81,0x9F,0x58,0x05,0x56,0xC3,0xCE,0x11,0xBF,0x01,0x00,0xAA,0x00,0x55,0x59,0x5A};
394 static const ff_asf_guid format_videoinfo2 =
395     {0xA0,0x76,0x2A,0xF7,0x0A,0xEB,0xD0,0x11,0xAC,0xE4,0x00,0x00,0xC0,0xCC,0x16,0xBA};
396 static const ff_asf_guid format_mpeg2_video =
397     {0xE3,0x80,0x6D,0xE0,0x46,0xDB,0xCF,0x11,0xB4,0xD1,0x00,0x80,0x5F,0x6C,0xBB,0xEA};
398 static const ff_asf_guid format_none =
399     {0xD6,0x17,0x64,0x0F,0x18,0xC3,0xD0,0x11,0xA4,0x3F,0x00,0xA0,0xC9,0x22,0x31,0x96};
400
401 static const AVCodecGuid video_guids[] = {
402     {AV_CODEC_ID_MPEG2VIDEO, {0x26,0x80,0x6D,0xE0,0x46,0xDB,0xCF,0x11,0xB4,0xD1,0x00,0x80,0x5F,0x6C,0xBB,0xEA}},
403     {AV_CODEC_ID_NONE}
404 };
405
406 static int read_probe(AVProbeData *p)
407 {
408     return ff_guidcmp(p->buf, wtv_guid) ? 0 : AVPROBE_SCORE_MAX;
409 }
410
411 /**
412  * Convert win32 FILETIME to ISO-8601 string
413  */
414 static void filetime_to_iso8601(char *buf, int buf_size, int64_t value)
415 {
416     time_t t = (value / 10000000LL) - 11644473600LL;
417     struct tm *tm = gmtime(&t);
418     if (tm)
419         strftime(buf, buf_size, "%Y-%m-%d %H:%M:%S", gmtime(&t));
420     else
421         buf[0] = '\0';
422 }
423
424 /**
425  * Convert crazy time (100ns since 1 Jan 0001) to ISO-8601 string
426  */
427 static void crazytime_to_iso8601(char *buf, int buf_size, int64_t value)
428 {
429     time_t t = (value / 10000000LL) - 719162LL*86400LL;
430     struct tm *tm = gmtime(&t);
431     if (tm)
432         strftime(buf, buf_size, "%Y-%m-%d %H:%M:%S", gmtime(&t));
433     else
434         buf[0] = '\0';
435 }
436
437 /**
438  * Convert OLE DATE to ISO-8601 string
439  */
440 static void oledate_to_iso8601(char *buf, int buf_size, int64_t value)
441 {
442     time_t t = 631112400LL + 86400*av_int2double(value);
443     struct tm *tm = gmtime(&t);
444     if (tm)
445         strftime(buf, buf_size, "%Y-%m-%d %H:%M:%S", gmtime(&t));
446     else
447         buf[0] = '\0';
448 }
449
450 static void get_attachment(AVFormatContext *s, AVIOContext *pb, int length)
451 {
452     char mime[1024];
453     char description[1024];
454     unsigned int filesize;
455     AVStream *st;
456     int64_t pos = avio_tell(pb);
457
458     avio_get_str16le(pb, INT_MAX, mime, sizeof(mime));
459     if (strcmp(mime, "image/jpeg"))
460         goto done;
461
462     avio_r8(pb);
463     avio_get_str16le(pb, INT_MAX, description, sizeof(description));
464     filesize = avio_rl32(pb);
465     if (!filesize)
466         goto done;
467
468     st = avformat_new_stream(s, NULL);
469     if (!st)
470         goto done;
471     av_dict_set(&st->metadata, "title", description, 0);
472     st->codec->codec_id   = AV_CODEC_ID_MJPEG;
473     st->codec->codec_type = AVMEDIA_TYPE_ATTACHMENT;
474     st->codec->extradata  = av_mallocz(filesize);
475     st->id = -1;
476     if (!st->codec->extradata)
477         goto done;
478     st->codec->extradata_size = filesize;
479     avio_read(pb, st->codec->extradata, filesize);
480 done:
481     avio_seek(pb, pos + length, SEEK_SET);
482 }
483
484 static void get_tag(AVFormatContext *s, AVIOContext *pb, const char *key, int type, int length)
485 {
486     int buf_size = FFMAX(2*length, LEN_PRETTY_GUID) + 1;
487     char *buf = av_malloc(buf_size);
488     if (!buf)
489         return;
490
491     if (type == 0 && length == 4) {
492         snprintf(buf, buf_size, "%"PRIi32, avio_rl32(pb));
493     } else if (type == 1) {
494         avio_get_str16le(pb, length, buf, buf_size);
495         if (!strlen(buf)) {
496            av_free(buf);
497            return;
498         }
499     } else if (type == 3 && length == 4) {
500         strcpy(buf, avio_rl32(pb) ? "true" : "false");
501     } else if (type == 4 && length == 8) {
502         int64_t num = avio_rl64(pb);
503         if (!strcmp(key, "WM/EncodingTime") ||
504             !strcmp(key, "WM/MediaOriginalBroadcastDateTime"))
505             filetime_to_iso8601(buf, buf_size, num);
506         else if (!strcmp(key, "WM/WMRVEncodeTime") ||
507                  !strcmp(key, "WM/WMRVEndTime"))
508             crazytime_to_iso8601(buf, buf_size, num);
509         else if (!strcmp(key, "WM/WMRVExpirationDate"))
510             oledate_to_iso8601(buf, buf_size, num);
511         else if (!strcmp(key, "WM/WMRVBitrate"))
512             snprintf(buf, buf_size, "%f", av_int2double(num));
513         else
514             snprintf(buf, buf_size, "%"PRIi64, num);
515     } else if (type == 5 && length == 2) {
516         snprintf(buf, buf_size, "%"PRIi16, avio_rl16(pb));
517     } else if (type == 6 && length == 16) {
518         ff_asf_guid guid;
519         avio_read(pb, guid, 16);
520         snprintf(buf, buf_size, PRI_PRETTY_GUID, ARG_PRETTY_GUID(guid));
521     } else if (type == 2 && !strcmp(key, "WM/Picture")) {
522         get_attachment(s, pb, length);
523         av_freep(&buf);
524         return;
525     } else {
526         av_freep(&buf);
527         av_log(s, AV_LOG_WARNING, "unsupported metadata entry; key:%s, type:%d, length:0x%x\n", key, type, length);
528         avio_skip(pb, length);
529         return;
530     }
531
532     av_dict_set(&s->metadata, key, buf, 0);
533     av_freep(&buf);
534 }
535
536 /**
537  * Parse metadata entries
538  */
539 static void parse_legacy_attrib(AVFormatContext *s, AVIOContext *pb)
540 {
541     ff_asf_guid guid;
542     int length, type;
543     while(!pb->eof_reached) {
544         char key[1024];
545         ff_get_guid(pb, &guid);
546         type   = avio_rl32(pb);
547         length = avio_rl32(pb);
548         if (!length)
549             break;
550         if (ff_guidcmp(&guid, metadata_guid)) {
551             av_log(s, AV_LOG_WARNING, "unknown guid "FF_PRI_GUID", expected metadata_guid; "
552                    "remaining metadata entries ignored\n", FF_ARG_GUID(guid));
553             break;
554         }
555         avio_get_str16le(pb, INT_MAX, key, sizeof(key));
556         get_tag(s, pb, key, type, length);
557     }
558
559     ff_metadata_conv(&s->metadata, NULL, ff_asf_metadata_conv);
560 }
561
562 /**
563  * parse VIDEOINFOHEADER2 structure
564  * @return bytes consumed
565  */
566 static int parse_videoinfoheader2(AVFormatContext *s, AVStream *st)
567 {
568     WtvContext *wtv = s->priv_data;
569     AVIOContext *pb = wtv->pb;
570
571     avio_skip(pb, 72);  // picture aspect ratio is unreliable
572     ff_get_bmp_header(pb, st);
573
574     return 72 + 40;
575 }
576
577 /**
578  * Parse MPEG1WAVEFORMATEX extradata structure
579  */
580 static void parse_mpeg1waveformatex(AVStream *st)
581 {
582     /* fwHeadLayer */
583     switch (AV_RL16(st->codec->extradata)) {
584     case 0x0001 : st->codec->codec_id = AV_CODEC_ID_MP1; break;
585     case 0x0002 : st->codec->codec_id = AV_CODEC_ID_MP2; break;
586     case 0x0004 : st->codec->codec_id = AV_CODEC_ID_MP3; break;
587     }
588
589     st->codec->bit_rate = AV_RL32(st->codec->extradata + 2); /* dwHeadBitrate */
590
591     /* dwHeadMode */
592     switch (AV_RL16(st->codec->extradata + 6)) {
593     case 1 :
594     case 2 :
595     case 4 : st->codec->channels       = 2;
596              st->codec->channel_layout = AV_CH_LAYOUT_STEREO;
597              break;
598     case 8 : st->codec->channels       = 1;
599              st->codec->channel_layout = AV_CH_LAYOUT_MONO;
600              break;
601     }
602 }
603
604 /**
605  * Initialise stream
606  * @param st Stream to initialise, or NULL to create and initialise new stream
607  * @return NULL on error
608  */
609 static AVStream * new_stream(AVFormatContext *s, AVStream *st, int sid, int codec_type)
610 {
611     if (st) {
612         if (st->codec->extradata) {
613             av_freep(&st->codec->extradata);
614             st->codec->extradata_size = 0;
615         }
616     } else {
617         WtvStream *wst = av_mallocz(sizeof(WtvStream));
618         if (!wst)
619             return NULL;
620         st = avformat_new_stream(s, NULL);
621         if (!st)
622             return NULL;
623         st->id = sid;
624         st->priv_data = wst;
625     }
626     st->codec->codec_type = codec_type;
627     st->need_parsing      = AVSTREAM_PARSE_FULL;
628     avpriv_set_pts_info(st, 64, 1, 10000000);
629     return st;
630 }
631
632 /**
633  * parse Media Type structure and populate stream
634  * @param st         Stream, or NULL to create new stream
635  * @param mediatype  Mediatype GUID
636  * @param subtype    Subtype GUID
637  * @param formattype Format GUID
638  * @param size       Size of format buffer
639  * @return NULL on error
640  */
641 static AVStream * parse_media_type(AVFormatContext *s, AVStream *st, int sid,
642                                    ff_asf_guid mediatype, ff_asf_guid subtype,
643                                    ff_asf_guid formattype, int size)
644 {
645     WtvContext *wtv = s->priv_data;
646     AVIOContext *pb = wtv->pb;
647     if (!ff_guidcmp(subtype, mediasubtype_cpfilters_processed) &&
648         !ff_guidcmp(formattype, format_cpfilters_processed)) {
649         ff_asf_guid actual_subtype;
650         ff_asf_guid actual_formattype;
651
652         if (size < 32) {
653             av_log(s, AV_LOG_WARNING, "format buffer size underflow\n");
654             avio_skip(pb, size);
655             return NULL;
656         }
657
658         avio_skip(pb, size - 32);
659         ff_get_guid(pb, &actual_subtype);
660         ff_get_guid(pb, &actual_formattype);
661         avio_seek(pb, -size, SEEK_CUR);
662
663         st = parse_media_type(s, st, sid, mediatype, actual_subtype, actual_formattype, size - 32);
664         avio_skip(pb, 32);
665         return st;
666     } else if (!ff_guidcmp(mediatype, mediatype_audio)) {
667         st = new_stream(s, st, sid, AVMEDIA_TYPE_AUDIO);
668         if (!st)
669             return NULL;
670         if (!ff_guidcmp(formattype, format_waveformatex)) {
671             int ret = ff_get_wav_header(pb, st->codec, size);
672             if (ret < 0)
673                 return NULL;
674         } else {
675             if (ff_guidcmp(formattype, format_none))
676                 av_log(s, AV_LOG_WARNING, "unknown formattype:"FF_PRI_GUID"\n", FF_ARG_GUID(formattype));
677             avio_skip(pb, size);
678         }
679
680         if (!memcmp(subtype + 4, (const uint8_t[]){FF_MEDIASUBTYPE_BASE_GUID}, 12)) {
681             st->codec->codec_id = ff_wav_codec_get_id(AV_RL32(subtype), st->codec->bits_per_coded_sample);
682         } else if (!ff_guidcmp(subtype, mediasubtype_mpeg1payload)) {
683             if (st->codec->extradata && st->codec->extradata_size >= 22)
684                 parse_mpeg1waveformatex(st);
685             else
686                 av_log(s, AV_LOG_WARNING, "MPEG1WAVEFORMATEX underflow\n");
687         } else {
688             st->codec->codec_id = ff_codec_guid_get_id(ff_codec_wav_guids, subtype);
689             if (st->codec->codec_id == AV_CODEC_ID_NONE)
690                 av_log(s, AV_LOG_WARNING, "unknown subtype:"FF_PRI_GUID"\n", FF_ARG_GUID(subtype));
691         }
692         return st;
693     } else if (!ff_guidcmp(mediatype, mediatype_video)) {
694         st = new_stream(s, st, sid, AVMEDIA_TYPE_VIDEO);
695         if (!st)
696             return NULL;
697         if (!ff_guidcmp(formattype, format_videoinfo2)) {
698             int consumed = parse_videoinfoheader2(s, st);
699             avio_skip(pb, FFMAX(size - consumed, 0));
700         } else if (!ff_guidcmp(formattype, format_mpeg2_video)) {
701             int consumed = parse_videoinfoheader2(s, st);
702             avio_skip(pb, FFMAX(size - consumed, 0));
703         } else {
704             if (ff_guidcmp(formattype, format_none))
705                 av_log(s, AV_LOG_WARNING, "unknown formattype:"FF_PRI_GUID"\n", FF_ARG_GUID(formattype));
706             avio_skip(pb, size);
707         }
708
709         if (!memcmp(subtype + 4, (const uint8_t[]){FF_MEDIASUBTYPE_BASE_GUID}, 12)) {
710             st->codec->codec_id = ff_codec_get_id(ff_codec_bmp_tags, AV_RL32(subtype));
711         } else {
712             st->codec->codec_id = ff_codec_guid_get_id(video_guids, subtype);
713         }
714         if (st->codec->codec_id == AV_CODEC_ID_NONE)
715             av_log(s, AV_LOG_WARNING, "unknown subtype:"FF_PRI_GUID"\n", FF_ARG_GUID(subtype));
716         return st;
717     } else if (!ff_guidcmp(mediatype, mediatype_mpeg2_pes) &&
718                !ff_guidcmp(subtype, mediasubtype_dvb_subtitle)) {
719         st = new_stream(s, st, sid, AVMEDIA_TYPE_SUBTITLE);
720         if (!st)
721             return NULL;
722         if (ff_guidcmp(formattype, format_none))
723             av_log(s, AV_LOG_WARNING, "unknown formattype:"FF_PRI_GUID"\n", FF_ARG_GUID(formattype));
724         avio_skip(pb, size);
725         st->codec->codec_id = AV_CODEC_ID_DVB_SUBTITLE;
726         return st;
727     } else if (!ff_guidcmp(mediatype, mediatype_mstvcaption) &&
728                (!ff_guidcmp(subtype, mediasubtype_teletext) || !ff_guidcmp(subtype, mediasubtype_dtvccdata))) {
729         st = new_stream(s, st, sid, AVMEDIA_TYPE_SUBTITLE);
730         if (!st)
731             return NULL;
732         if (ff_guidcmp(formattype, format_none))
733             av_log(s, AV_LOG_WARNING, "unknown formattype:"FF_PRI_GUID"\n", FF_ARG_GUID(formattype));
734         avio_skip(pb, size);
735         st->codec->codec_id   = AV_CODEC_ID_DVB_TELETEXT;
736         return st;
737     } else if (!ff_guidcmp(mediatype, mediatype_mpeg2_sections) &&
738                !ff_guidcmp(subtype, mediasubtype_mpeg2_sections)) {
739         if (ff_guidcmp(formattype, format_none))
740             av_log(s, AV_LOG_WARNING, "unknown formattype:"FF_PRI_GUID"\n", FF_ARG_GUID(formattype));
741         avio_skip(pb, size);
742         return NULL;
743     }
744
745     av_log(s, AV_LOG_WARNING, "unknown media type, mediatype:"FF_PRI_GUID
746                               ", subtype:"FF_PRI_GUID", formattype:"FF_PRI_GUID"\n",
747                               FF_ARG_GUID(mediatype), FF_ARG_GUID(subtype), FF_ARG_GUID(formattype));
748     avio_skip(pb, size);
749     return NULL;
750 }
751
752 enum {
753     SEEK_TO_DATA = 0,
754     SEEK_TO_PTS,
755 };
756
757 /**
758  * Parse WTV chunks
759  * @param mode SEEK_TO_DATA or SEEK_TO_PTS
760  * @param seekts timestamp
761  * @param[out] len_ptr Length of data chunk
762  * @return stream index of data chunk, or <0 on error
763  */
764 static int parse_chunks(AVFormatContext *s, int mode, int64_t seekts, int *len_ptr)
765 {
766     WtvContext *wtv = s->priv_data;
767     AVIOContext *pb = wtv->pb;
768     while (!pb->eof_reached) {
769         ff_asf_guid g;
770         int len, sid, consumed;
771
772         ff_get_guid(pb, &g);
773         len = avio_rl32(pb);
774         if (len < 32)
775             break;
776         sid = avio_rl32(pb) & 0x7FFF;
777         avio_skip(pb, 8);
778         consumed = 32;
779
780         if (!ff_guidcmp(g, stream_guid)) {
781             if (ff_find_stream_index(s, sid) < 0) {
782                 ff_asf_guid mediatype, subtype, formattype;
783                 int size;
784                 avio_skip(pb, 28);
785                 ff_get_guid(pb, &mediatype);
786                 ff_get_guid(pb, &subtype);
787                 avio_skip(pb, 12);
788                 ff_get_guid(pb, &formattype);
789                 size = avio_rl32(pb);
790                 parse_media_type(s, 0, sid, mediatype, subtype, formattype, size);
791                 consumed += 92 + size;
792             }
793         } else if (!ff_guidcmp(g, stream2_guid)) {
794             int stream_index = ff_find_stream_index(s, sid);
795             if (stream_index >= 0 && !((WtvStream*)s->streams[stream_index]->priv_data)->seen_data) {
796                 ff_asf_guid mediatype, subtype, formattype;
797                 int size;
798                 avio_skip(pb, 12);
799                 ff_get_guid(pb, &mediatype);
800                 ff_get_guid(pb, &subtype);
801                 avio_skip(pb, 12);
802                 ff_get_guid(pb, &formattype);
803                 size = avio_rl32(pb);
804                 parse_media_type(s, s->streams[stream_index], sid, mediatype, subtype, formattype, size);
805                 consumed += 76 + size;
806             }
807         } else if (!ff_guidcmp(g, EVENTID_AudioDescriptorSpanningEvent) ||
808                    !ff_guidcmp(g, EVENTID_CtxADescriptorSpanningEvent) ||
809                    !ff_guidcmp(g, EVENTID_CSDescriptorSpanningEvent) ||
810                    !ff_guidcmp(g, EVENTID_StreamIDSpanningEvent) ||
811                    !ff_guidcmp(g, EVENTID_SubtitleSpanningEvent) ||
812                    !ff_guidcmp(g, EVENTID_TeletextSpanningEvent)) {
813             int stream_index = ff_find_stream_index(s, sid);
814             if (stream_index >= 0) {
815                 AVStream *st = s->streams[stream_index];
816                 uint8_t buf[258];
817                 const uint8_t *pbuf = buf;
818                 int buf_size;
819
820                 avio_skip(pb, 8);
821                 consumed += 8;
822                 if (!ff_guidcmp(g, EVENTID_CtxADescriptorSpanningEvent) ||
823                     !ff_guidcmp(g, EVENTID_CSDescriptorSpanningEvent)) {
824                     avio_skip(pb, 6);
825                     consumed += 6;
826                 }
827
828                 buf_size = FFMIN(len - consumed, sizeof(buf));
829                 avio_read(pb, buf, buf_size);
830                 consumed += buf_size;
831                 ff_parse_mpeg2_descriptor(s, st, 0, &pbuf, buf + buf_size, NULL, 0, 0, NULL);
832             }
833         } else if (!ff_guidcmp(g, EVENTID_AudioTypeSpanningEvent)) {
834             int stream_index = ff_find_stream_index(s, sid);
835             if (stream_index >= 0) {
836                 AVStream *st = s->streams[stream_index];
837                 int audio_type;
838                 avio_skip(pb, 8);
839                 audio_type = avio_r8(pb);
840                 if (audio_type == 2)
841                     st->disposition |= AV_DISPOSITION_HEARING_IMPAIRED;
842                 else if (audio_type == 3)
843                     st->disposition |= AV_DISPOSITION_VISUAL_IMPAIRED;
844                 consumed += 9;
845             }
846         } else if (!ff_guidcmp(g, EVENTID_DVBScramblingControlSpanningEvent)) {
847             int stream_index = ff_find_stream_index(s, sid);
848             if (stream_index >= 0) {
849                 avio_skip(pb, 12);
850                 if (avio_rl32(pb))
851                     av_log(s, AV_LOG_WARNING, "DVB scrambled stream detected (st:%d), decoding will likely fail\n", stream_index);
852                 consumed += 16;
853             }
854         } else if (!ff_guidcmp(g, EVENTID_LanguageSpanningEvent)) {
855             int stream_index = ff_find_stream_index(s, sid);
856             if (stream_index >= 0) {
857                 AVStream *st = s->streams[stream_index];
858                 uint8_t language[4];
859                 avio_skip(pb, 12);
860                 avio_read(pb, language, 3);
861                 if (language[0]) {
862                     language[3] = 0;
863                     av_dict_set(&st->metadata, "language", language, 0);
864                     if (!strcmp(language, "nar") || !strcmp(language, "NAR"))
865                         st->disposition |= AV_DISPOSITION_VISUAL_IMPAIRED;
866                 }
867                 consumed += 15;
868             }
869         } else if (!ff_guidcmp(g, timestamp_guid)) {
870             int stream_index = ff_find_stream_index(s, sid);
871             if (stream_index >= 0) {
872                 avio_skip(pb, 8);
873                 wtv->pts = avio_rl64(pb);
874                 consumed += 16;
875                 if (wtv->pts == -1)
876                     wtv->pts = AV_NOPTS_VALUE;
877                 else {
878                     wtv->last_valid_pts = wtv->pts;
879                     if (wtv->epoch == AV_NOPTS_VALUE || wtv->pts < wtv->epoch)
880                         wtv->epoch = wtv->pts;
881                 if (mode == SEEK_TO_PTS && wtv->pts >= seekts) {
882 #define WTV_PAD8(x) (((x) + 7) & ~7)
883                     avio_skip(pb, WTV_PAD8(len) - consumed);
884                     return 0;
885                 }
886                 }
887             }
888         } else if (!ff_guidcmp(g, data_guid)) {
889             int stream_index = ff_find_stream_index(s, sid);
890             if (mode == SEEK_TO_DATA && stream_index >= 0 && len > 32) {
891                 WtvStream *wst = s->streams[stream_index]->priv_data;
892                 wst->seen_data = 1;
893                 if (len_ptr) {
894                     *len_ptr = len;
895                 }
896                 return stream_index;
897             }
898         } else if (
899             !ff_guidcmp(g, /* DSATTRIB_CAPTURE_STREAMTIME */ (const ff_asf_guid){0x14,0x56,0x1A,0x0C,0xCD,0x30,0x40,0x4F,0xBC,0xBF,0xD0,0x3E,0x52,0x30,0x62,0x07}) ||
900             !ff_guidcmp(g, /* DSATTRIB_PicSampleSeq */ (const ff_asf_guid){0x02,0xAE,0x5B,0x2F,0x8F,0x7B,0x60,0x4F,0x82,0xD6,0xE4,0xEA,0x2F,0x1F,0x4C,0x99}) ||
901             !ff_guidcmp(g, /* DSATTRIB_TRANSPORT_PROPERTIES */ (const ff_asf_guid){0x12,0xF6,0x22,0xB6,0xAD,0x47,0x71,0x46,0xAD,0x6C,0x05,0xA9,0x8E,0x65,0xDE,0x3A}) ||
902             !ff_guidcmp(g, /* dvr_ms_vid_frame_rep_data */ (const ff_asf_guid){0xCC,0x32,0x64,0xDD,0x29,0xE2,0xDB,0x40,0x80,0xF6,0xD2,0x63,0x28,0xD2,0x76,0x1F}) ||
903             !ff_guidcmp(g, /* EVENTID_ChannelChangeSpanningEvent */ (const ff_asf_guid){0xE5,0xC5,0x67,0x90,0x5C,0x4C,0x05,0x42,0x86,0xC8,0x7A,0xFE,0x20,0xFE,0x1E,0xFA}) ||
904             !ff_guidcmp(g, /* EVENTID_ChannelInfoSpanningEvent */ (const ff_asf_guid){0x80,0x6D,0xF3,0x41,0x32,0x41,0xC2,0x4C,0xB1,0x21,0x01,0xA4,0x32,0x19,0xD8,0x1B}) ||
905             !ff_guidcmp(g, /* EVENTID_ChannelTypeSpanningEvent */ (const ff_asf_guid){0x51,0x1D,0xAB,0x72,0xD2,0x87,0x9B,0x48,0xBA,0x11,0x0E,0x08,0xDC,0x21,0x02,0x43}) ||
906             !ff_guidcmp(g, /* EVENTID_PIDListSpanningEvent */ (const ff_asf_guid){0x65,0x8F,0xFC,0x47,0xBB,0xE2,0x34,0x46,0x9C,0xEF,0xFD,0xBF,0xE6,0x26,0x1D,0x5C}) ||
907             !ff_guidcmp(g, /* EVENTID_SignalAndServiceStatusSpanningEvent */ (const ff_asf_guid){0xCB,0xC5,0x68,0x80,0x04,0x3C,0x2B,0x49,0xB4,0x7D,0x03,0x08,0x82,0x0D,0xCE,0x51}) ||
908             !ff_guidcmp(g, /* EVENTID_StreamTypeSpanningEvent */ (const ff_asf_guid){0xBC,0x2E,0xAF,0x82,0xA6,0x30,0x64,0x42,0xA8,0x0B,0xAD,0x2E,0x13,0x72,0xAC,0x60}) ||
909             !ff_guidcmp(g, (const ff_asf_guid){0x1E,0xBE,0xC3,0xC5,0x43,0x92,0xDC,0x11,0x85,0xE5,0x00,0x12,0x3F,0x6F,0x73,0xB9}) ||
910             !ff_guidcmp(g, (const ff_asf_guid){0x3B,0x86,0xA2,0xB1,0xEB,0x1E,0xC3,0x44,0x8C,0x88,0x1C,0xA3,0xFF,0xE3,0xE7,0x6A}) ||
911             !ff_guidcmp(g, (const ff_asf_guid){0x4E,0x7F,0x4C,0x5B,0xC4,0xD0,0x38,0x4B,0xA8,0x3E,0x21,0x7F,0x7B,0xBF,0x52,0xE7}) ||
912             !ff_guidcmp(g, (const ff_asf_guid){0x63,0x36,0xEB,0xFE,0xA1,0x7E,0xD9,0x11,0x83,0x08,0x00,0x07,0xE9,0x5E,0xAD,0x8D}) ||
913             !ff_guidcmp(g, (const ff_asf_guid){0x70,0xE9,0xF1,0xF8,0x89,0xA4,0x4C,0x4D,0x83,0x73,0xB8,0x12,0xE0,0xD5,0xF8,0x1E}) ||
914             !ff_guidcmp(g, (const ff_asf_guid){0x96,0xC3,0xD2,0xC2,0x7E,0x9A,0xDA,0x11,0x8B,0xF7,0x00,0x07,0xE9,0x5E,0xAD,0x8D}) ||
915             !ff_guidcmp(g, (const ff_asf_guid){0x97,0xC3,0xD2,0xC2,0x7E,0x9A,0xDA,0x11,0x8B,0xF7,0x00,0x07,0xE9,0x5E,0xAD,0x8D}) ||
916             !ff_guidcmp(g, (const ff_asf_guid){0xA1,0xC3,0xD2,0xC2,0x7E,0x9A,0xDA,0x11,0x8B,0xF7,0x00,0x07,0xE9,0x5E,0xAD,0x8D})) {
917             //ignore known guids
918         } else
919             av_log(s, AV_LOG_WARNING, "unsupported chunk:"FF_PRI_GUID"\n", FF_ARG_GUID(g));
920
921         avio_skip(pb, WTV_PAD8(len) - consumed);
922     }
923     return AVERROR_EOF;
924 }
925
926 /* declare utf16le strings */
927 #define _ , 0,
928 static const uint8_t timeline_le16[] =
929     {'t'_'i'_'m'_'e'_'l'_'i'_'n'_'e', 0};
930 static const uint8_t table_0_entries_legacy_attrib_le16[] =
931     {'t'_'a'_'b'_'l'_'e'_'.'_'0'_'.'_'e'_'n'_'t'_'r'_'i'_'e'_'s'_'.'_'l'_'e'_'g'_'a'_'c'_'y'_'_'_'a'_'t'_'t'_'r'_'i'_'b', 0};
932 static const uint8_t table_0_entries_time_le16[] =
933     {'t'_'a'_'b'_'l'_'e'_'.'_'0'_'.'_'e'_'n'_'t'_'r'_'i'_'e'_'s'_'.'_'t'_'i'_'m'_'e', 0};
934 static const uint8_t timeline_table_0_entries_Events_le16[] =
935     {'t'_'i'_'m'_'e'_'l'_'i'_'n'_'e'_'.'_'t'_'a'_'b'_'l'_'e'_'.'_'0'_'.'_'e'_'n'_'t'_'r'_'i'_'e'_'s'_'.'_'E'_'v'_'e'_'n'_'t'_'s', 0};
936 #undef _
937
938 static int read_header(AVFormatContext *s)
939 {
940     WtvContext *wtv = s->priv_data;
941     int root_sector, root_size;
942     uint8_t root[WTV_SECTOR_SIZE];
943     AVIOContext *pb;
944     int64_t timeline_pos;
945     int ret;
946
947     wtv->epoch          =
948     wtv->pts            =
949     wtv->last_valid_pts = AV_NOPTS_VALUE;
950
951     /* read root directory sector */
952     avio_skip(s->pb, 0x30);
953     root_size = avio_rl32(s->pb);
954     if (root_size > sizeof(root)) {
955         av_log(s, AV_LOG_ERROR, "root directory size exceeds sector size\n");
956         return AVERROR_INVALIDDATA;
957     }
958     avio_skip(s->pb, 4);
959     root_sector = avio_rl32(s->pb);
960
961     avio_seek(s->pb, root_sector << WTV_SECTOR_BITS, SEEK_SET);
962     root_size = avio_read(s->pb, root, root_size);
963     if (root_size < 0)
964         return AVERROR_INVALIDDATA;
965
966     /* parse chunks up until first data chunk */
967     wtv->pb = wtvfile_open(s, root, root_size, timeline_le16);
968     if (!wtv->pb) {
969         av_log(s, AV_LOG_ERROR, "timeline data missing\n");
970         return AVERROR_INVALIDDATA;
971     }
972
973     ret = parse_chunks(s, SEEK_TO_DATA, 0, 0);
974     if (ret < 0)
975         return ret;
976     avio_seek(wtv->pb, -32, SEEK_CUR);
977
978     timeline_pos = avio_tell(s->pb); // save before opening another file
979
980     /* read metadata */
981     pb = wtvfile_open(s, root, root_size, table_0_entries_legacy_attrib_le16);
982     if (pb) {
983         parse_legacy_attrib(s, pb);
984         wtvfile_close(pb);
985     }
986
987     /* read seek index */
988     if (s->nb_streams) {
989         AVStream *st = s->streams[0];
990         pb = wtvfile_open(s, root, root_size, table_0_entries_time_le16);
991         if (pb) {
992             while(1) {
993                 uint64_t timestamp = avio_rl64(pb);
994                 uint64_t frame_nb  = avio_rl64(pb);
995                 if (pb->eof_reached)
996                     break;
997                 ff_add_index_entry(&wtv->index_entries, &wtv->nb_index_entries, &wtv->index_entries_allocated_size,
998                                    0, timestamp, frame_nb, 0, AVINDEX_KEYFRAME);
999             }
1000             wtvfile_close(pb);
1001
1002             if (wtv->nb_index_entries) {
1003                 pb = wtvfile_open(s, root, root_size, timeline_table_0_entries_Events_le16);
1004                 if (pb) {
1005                     int i;
1006                     while (1) {
1007                         uint64_t frame_nb = avio_rl64(pb);
1008                         uint64_t position = avio_rl64(pb);
1009                         if (pb->eof_reached)
1010                             break;
1011                         for (i = wtv->nb_index_entries - 1; i >= 0; i--) {
1012                             AVIndexEntry *e = wtv->index_entries + i;
1013                             if (frame_nb > e->size)
1014                                 break;
1015                             if (position > e->pos)
1016                                 e->pos = position;
1017                         }
1018                     }
1019                     wtvfile_close(pb);
1020                     st->duration = wtv->index_entries[wtv->nb_index_entries - 1].timestamp;
1021                 }
1022             }
1023         }
1024     }
1025
1026     avio_seek(s->pb, timeline_pos, SEEK_SET);
1027     return 0;
1028 }
1029
1030 static int read_packet(AVFormatContext *s, AVPacket *pkt)
1031 {
1032     WtvContext *wtv = s->priv_data;
1033     AVIOContext *pb = wtv->pb;
1034     int stream_index, len, ret;
1035
1036     stream_index = parse_chunks(s, SEEK_TO_DATA, 0, &len);
1037     if (stream_index < 0)
1038         return stream_index;
1039
1040     ret = av_get_packet(pb, pkt, len - 32);
1041     if (ret < 0)
1042         return ret;
1043     pkt->stream_index = stream_index;
1044     pkt->pts          = wtv->pts;
1045     avio_skip(pb, WTV_PAD8(len) - len);
1046     return 0;
1047 }
1048
1049 static int read_seek(AVFormatContext *s, int stream_index,
1050                      int64_t ts, int flags)
1051 {
1052     WtvContext *wtv = s->priv_data;
1053     AVIOContext *pb = wtv->pb;
1054     AVStream *st = s->streams[0];
1055     int64_t ts_relative;
1056     int i;
1057
1058     if ((flags & AVSEEK_FLAG_FRAME) || (flags & AVSEEK_FLAG_BYTE))
1059         return AVERROR(ENOSYS);
1060
1061     /* timestamp adjustment is required because wtv->pts values are absolute,
1062      * whereas AVIndexEntry->timestamp values are relative to epoch. */
1063     ts_relative = ts;
1064     if (wtv->epoch != AV_NOPTS_VALUE)
1065         ts_relative -= wtv->epoch;
1066
1067     i = ff_index_search_timestamp(wtv->index_entries, wtv->nb_index_entries, ts_relative, flags);
1068     if (i < 0) {
1069         if (wtv->last_valid_pts == AV_NOPTS_VALUE || ts < wtv->last_valid_pts)
1070             avio_seek(pb, 0, SEEK_SET);
1071         else if (st->duration != AV_NOPTS_VALUE && ts_relative > st->duration && wtv->nb_index_entries)
1072             avio_seek(pb, wtv->index_entries[wtv->nb_index_entries - 1].pos, SEEK_SET);
1073         if (parse_chunks(s, SEEK_TO_PTS, ts, 0) < 0)
1074             return AVERROR(ERANGE);
1075         return 0;
1076     }
1077     wtv->pts = wtv->index_entries[i].timestamp;
1078     if (wtv->epoch != AV_NOPTS_VALUE)
1079         wtv->pts += wtv->epoch;
1080     wtv->last_valid_pts = wtv->pts;
1081     avio_seek(pb, wtv->index_entries[i].pos, SEEK_SET);
1082     return 0;
1083 }
1084
1085 static int read_close(AVFormatContext *s)
1086 {
1087     WtvContext *wtv = s->priv_data;
1088     av_free(wtv->index_entries);
1089     wtvfile_close(wtv->pb);
1090     return 0;
1091 }
1092
1093 AVInputFormat ff_wtv_demuxer = {
1094     .name           = "wtv",
1095     .long_name      = NULL_IF_CONFIG_SMALL("Windows Television (WTV)"),
1096     .priv_data_size = sizeof(WtvContext),
1097     .read_probe     = read_probe,
1098     .read_header    = read_header,
1099     .read_packet    = read_packet,
1100     .read_seek      = read_seek,
1101     .read_close     = read_close,
1102     .flags          = AVFMT_SHOW_IDS,
1103 };