wtv: do not repopulate codec information after we have seen data chunks
[ffmpeg.git] / libavformat / wtv.c
1 /*
2  * Windows Television (WTV) demuxer
3  * Copyright (c) 2010 Peter Ross <pross@xvid.org>
4  *
5  * This file is part of FFmpeg.
6  *
7  * FFmpeg is free software; you can redistribute it and/or
8  * modify it under the terms of the GNU Lesser General Public
9  * License as published by the Free Software Foundation; either
10  * version 2.1 of the License, or (at your option) any later version.
11  *
12  * FFmpeg is distributed in the hope that it will be useful,
13  * but WITHOUT ANY WARRANTY; without even the implied warranty of
14  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
15  * Lesser General Public License for more details.
16  *
17  * You should have received a copy of the GNU Lesser General Public
18  * License along with FFmpeg; if not, write to the Free Software
19  * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA
20  */
21
22 /**
23  * @file
24  * Windows Television (WTV) demuxer
25  * @author Peter Ross <pross@xvid.org>
26  */
27
28 #include "libavutil/intreadwrite.h"
29 #include "avformat.h"
30 #include "riff.h"
31 #include "asf.h"
32 #include "mpegts.h"
33
34 /* Macros for formating GUIDs */
35 #define PRI_GUID \
36     "%02x%02x%02x%02x%02x%02x%02x%02x%02x%02x%02x%02x%02x%02x%02x%02x"
37 #define ARG_GUID(g) \
38     g[0],g[1],g[2],g[3],g[4],g[5],g[6],g[7],g[8],g[9],g[10],g[11],g[12],g[13],g[14],g[15]
39
40 typedef struct {
41     int seen_data;
42 } WtvStream;
43
44 typedef struct WtvContext {
45     uint64_t pts;
46 } WtvContext;
47
48 static int is_zero(uint8_t *v, int n)
49 {
50    int i;
51    for (i = 0; i < n; i++)
52       if (v[i]) return 0;
53    return 1;
54 }
55
56 typedef struct {
57     enum CodecID id;
58     ff_asf_guid guid;
59 } AVCodecGuid;
60
61 static enum CodecID ff_codec_guid_get_id(const AVCodecGuid *guids, ff_asf_guid guid)
62 {
63     int i;
64     for (i = 0; guids[i].id != CODEC_ID_NONE; i++) {
65         if (!ff_guidcmp(guids[i].guid, guid))
66             return guids[i].id;
67     }
68     return CODEC_ID_NONE;
69 }
70
71 /* WTV GUIDs */
72 static const ff_asf_guid wtv_guid =
73     {0xB7,0xD8,0x00,0x20,0x37,0x49,0xDA,0x11,0xA6,0x4E,0x00,0x07,0xE9,0x5E,0xAD,0x8D};
74 static const ff_asf_guid meta_guid =
75     {0x5A,0xFE,0xD7,0x6D,0xC8,0x1D,0x8F,0x4A,0x99,0x22,0xFA,0xB1,0x1C,0x38,0x14,0x53};
76 static const ff_asf_guid timestamp_guid =
77     {0x5B,0x05,0xE6,0x1B,0x97,0xA9,0x49,0x43,0x88,0x17,0x1A,0x65,0x5A,0x29,0x8A,0x97};
78 static const ff_asf_guid data_guid =
79     {0x95,0xC3,0xD2,0xC2,0x7E,0x9A,0xDA,0x11,0x8B,0xF7,0x00,0x07,0xE9,0x5E,0xAD,0x8D};
80 static const ff_asf_guid stream_guid =
81     {0xED,0xA4,0x13,0x23,0x2D,0xBF,0x4F,0x45,0xAD,0x8A,0xD9,0x5B,0xA7,0xF9,0x1F,0xEE};
82 static const ff_asf_guid stream2_guid =
83     {0xA2,0xC3,0xD2,0xC2,0x7E,0x9A,0xDA,0x11,0x8B,0xF7,0x00,0x07,0xE9,0x5E,0xAD,0x8D};
84 static const ff_asf_guid EVENTID_SubtitleSpanningEvent =
85     {0x48,0xC0,0xCE,0x5D,0xB9,0xD0,0x63,0x41,0x87,0x2C,0x4F,0x32,0x22,0x3B,0xE8,0x8A};
86 static const ff_asf_guid EVENTID_LanguageSpanningEvent =
87     {0x6D,0x66,0x92,0xE2,0x02,0x9C,0x8D,0x44,0xAA,0x8D,0x78,0x1A,0x93,0xFD,0xC3,0x95};
88 static const ff_asf_guid EVENTID_AudioDescriptorSpanningEvent =
89     {0x1C,0xD4,0x7B,0x10,0xDA,0xA6,0x91,0x46,0x83,0x69,0x11,0xB2,0xCD,0xAA,0x28,0x8E};
90 static const ff_asf_guid EVENTID_CtxADescriptorSpanningEvent =
91     {0xE6,0xA2,0xB4,0x3A,0x47,0x42,0x34,0x4B,0x89,0x6C,0x30,0xAF,0xA5,0xD2,0x1C,0x24};
92 static const ff_asf_guid EVENTID_CSDescriptorSpanningEvent =
93     {0xD9,0x79,0xE7,0xEf,0xF0,0x97,0x86,0x47,0x80,0x0D,0x95,0xCF,0x50,0x5D,0xDC,0x66};
94 static const ff_asf_guid EVENTID_DVBScramblingControlSpanningEvent =
95     {0xC4,0xE1,0xD4,0x4B,0xA1,0x90,0x09,0x41,0x82,0x36,0x27,0xF0,0x0E,0x7D,0xCC,0x5B};
96 static const ff_asf_guid EVENTID_StreamIDSpanningEvent =
97     {0x68,0xAB,0xF1,0xCA,0x53,0xE1,0x41,0x4D,0xA6,0xB3,0xA7,0xC9,0x98,0xDB,0x75,0xEE};
98 static const ff_asf_guid EVENTID_TeletextSpanningEvent =
99     {0x50,0xD9,0x99,0x95,0x33,0x5F,0x17,0x46,0xAF,0x7C,0x1E,0x54,0xB5,0x10,0xDA,0xA3};
100
101 /* Windows media GUIDs */
102
103 #define MEDIASUBTYPE_BASE_GUID \
104     0x00,0x00,0x10,0x00,0x80,0x00,0x00,0xAA,0x00,0x38,0x9B,0x71
105
106 /* Media types */
107 static const ff_asf_guid mediatype_audio =
108     {'a','u','d','s',MEDIASUBTYPE_BASE_GUID};
109 static const ff_asf_guid mediatype_video =
110     {'v','i','d','s',MEDIASUBTYPE_BASE_GUID};
111 static const ff_asf_guid mediasubtype_mpeg1payload =
112     {0x81,0xEB,0x36,0xE4,0x4F,0x52,0xCE,0x11,0x9F,0x53,0x00,0x20,0xAF,0x0B,0xA7,0x70};
113 static const ff_asf_guid mediatype_mpeg2_sections =
114     {0x6C,0x17,0x5F,0x45,0x06,0x4B,0xCE,0x47,0x9A,0xEF,0x8C,0xAE,0xF7,0x3D,0xF7,0xB5};
115 static const ff_asf_guid mediatype_mpeg2_pes =
116     {0x20,0x80,0x6D,0xE0,0x46,0xDB,0xCF,0x11,0xB4,0xD1,0x00,0x80,0x5F,0x6C,0xBB,0xEA};
117 static const ff_asf_guid mediatype_mstvcaption =
118     {0x89,0x8A,0x8B,0xB8,0x49,0xB0,0x80,0x4C,0xAD,0xCF,0x58,0x98,0x98,0x5E,0x22,0xC1};
119
120 /* Media subtypes */
121 static const ff_asf_guid mediasubtype_cpfilters_processed =
122     {0x28,0xBD,0xAD,0x46,0xD0,0x6F,0x96,0x47,0x93,0xB2,0x15,0x5C,0x51,0xDC,0x04,0x8D};
123 static const ff_asf_guid mediasubtype_dvb_subtitle =
124     {0xC3,0xCB,0xFF,0x34,0xB3,0xD5,0x71,0x41,0x90,0x02,0xD4,0xC6,0x03,0x01,0x69,0x7F};
125 static const ff_asf_guid mediasubtype_teletext =
126     {0xE3,0x76,0x2A,0xF7,0x0A,0xEB,0xD0,0x11,0xAC,0xE4,0x00,0x00,0xC0,0xCC,0x16,0xBA};
127 static const ff_asf_guid mediasubtype_dtvccdata =
128     {0xAA,0xDD,0x2A,0xF5,0xF0,0x36,0xF5,0x43,0x95,0xEA,0x6D,0x86,0x64,0x84,0x26,0x2A};
129 static const ff_asf_guid mediasubtype_mpeg2_sections =
130     {0x79,0x85,0x9F,0x4A,0xF8,0x6B,0x92,0x43,0x8A,0x6D,0xD2,0xDD,0x09,0xFA,0x78,0x61};
131
132 /* Formats */
133 static const ff_asf_guid format_cpfilters_processed =
134     {0x6F,0xB3,0x39,0x67,0x5F,0x1D,0xC2,0x4A,0x81,0x92,0x28,0xBB,0x0E,0x73,0xD1,0x6A};
135 static const ff_asf_guid format_waveformatex =
136     {0x81,0x9F,0x58,0x05,0x56,0xC3,0xCE,0x11,0xBF,0x01,0x00,0xAA,0x00,0x55,0x59,0x5A};
137 static const ff_asf_guid format_videoinfo2 =
138     {0xA0,0x76,0x2A,0xF7,0x0A,0xEB,0xD0,0x11,0xAC,0xE4,0x00,0x00,0xC0,0xCC,0x16,0xBA};
139 static const ff_asf_guid format_mpeg2_video =
140     {0xE3,0x80,0x6D,0xE0,0x46,0xDB,0xCF,0x11,0xB4,0xD1,0x00,0x80,0x5F,0x6C,0xBB,0xEA};
141 static const ff_asf_guid format_none =
142     {0xD6,0x17,0x64,0x0F,0x18,0xC3,0xD0,0x11,0xA4,0x3F,0x00,0xA0,0xC9,0x22,0x31,0x96};
143
144 static const AVCodecGuid video_guids[] = {
145     {CODEC_ID_MPEG2VIDEO, {0x26,0x80,0x6D,0xE0,0x46,0xDB,0xCF,0x11,0xB4,0xD1,0x00,0x80,0x5F,0x6C,0xBB,0xEA}},
146     {CODEC_ID_NONE}
147 };
148
149 static const AVCodecGuid audio_guids[] = {
150     {CODEC_ID_AC3,        {0x2C,0x80,0x6D,0xE0,0x46,0xDB,0xCF,0x11,0xB4,0xD1,0x00,0x80,0x5F,0x6C,0xBB,0xEA}},
151     {CODEC_ID_EAC3,       {0xAF,0x87,0xFB,0xA7,0x02,0x2D,0xFB,0x42,0xA4,0xD4,0x05,0xCD,0x93,0x84,0x3B,0xDD}},
152     {CODEC_ID_MP2,        {0x2B,0x80,0x6D,0xE0,0x46,0xDB,0xCF,0x11,0xB4,0xD1,0x00,0x80,0x5F,0x6C,0xBB,0xEA}},
153     {CODEC_ID_NONE}
154 };
155
156 static int read_probe(AVProbeData *p)
157 {
158     return ff_guidcmp(p->buf, wtv_guid) ? 0 : AVPROBE_SCORE_MAX;
159 }
160
161 /**
162  * parse VIDEOINFOHEADER2 structure
163  * @return bytes consumed
164  */
165 static int parse_videoinfoheader2(AVFormatContext *s, AVStream *st)
166 {
167     ByteIOContext *pb = s->pb;
168
169     url_fskip(pb, 32);
170     st->codec->bit_rate = get_le32(pb);
171     url_fskip(pb, 20);
172     st->sample_aspect_ratio.num = get_le32(pb);
173     st->sample_aspect_ratio.den = get_le32(pb);
174     url_fskip(pb, 8);
175     ff_get_bmp_header(pb, st);
176
177     return 72 + 40;
178 }
179
180 /**
181  * Parse MPEG1WAVEFORMATEX extradata structure
182  */
183 static void parse_mpeg1waveformatex(AVStream *st)
184 {
185     /* fwHeadLayer */
186     switch (AV_RL16(st->codec->extradata)) {
187     case 0x0001 : st->codec->codec_id = CODEC_ID_MP1; break;
188     case 0x0002 : st->codec->codec_id = CODEC_ID_MP2; break;
189     case 0x0004 : st->codec->codec_id = CODEC_ID_MP3; break;
190     }
191
192     st->codec->bit_rate = AV_RL32(st->codec->extradata + 2); /* dwHeadBitrate */
193
194     /* dwHeadMode */
195     switch (AV_RL16(st->codec->extradata + 6)) {
196     case 1 : case 2 : case 4 : st->codec->channels = 2; break;
197     case 8 :                   st->codec->channels = 1; break;
198     }
199 }
200
201 /**
202  * Initialise stream
203  * @param st Stream to initialise, or NULL to create and initialise new stream
204  * @return NULL on error
205  */
206 static AVStream * new_stream(AVFormatContext *s, AVStream *st, int sid, int codec_type)
207 {
208     if (st) {
209         if (st->codec->extradata) {
210             av_freep(&st->codec->extradata);
211             st->codec->extradata_size = 0;
212         }
213     } else {
214         WtvStream *wst = av_mallocz(sizeof(WtvStream));
215         if (!wst)
216             return NULL;
217         st = av_new_stream(s, sid);
218         if (!st)
219             return NULL;
220         st->priv_data = wst;
221     }
222     st->codec->codec_type = codec_type;
223     st->need_parsing      = AVSTREAM_PARSE_FULL;
224     av_set_pts_info(st, 64, 1, 10000000);
225     return st;
226 }
227
228 /**
229  * parse Media Type structure and populate stream
230  * @param st         Stream, or NULL to create new stream
231  * @param mediatype  Mediatype GUID
232  * @param subtype    Subtype GUID
233  * @param formattype Format GUID
234  * @param size       Size of format buffer
235  * @return NULL on error
236  */
237 static AVStream * parse_media_type(AVFormatContext *s, AVStream *st, int sid,
238                                    ff_asf_guid mediatype, ff_asf_guid subtype,
239                                    ff_asf_guid formattype, int size)
240 {
241     ByteIOContext *pb = s->pb;
242     if (!ff_guidcmp(subtype, mediasubtype_cpfilters_processed) &&
243         !ff_guidcmp(formattype, format_cpfilters_processed)) {
244         ff_asf_guid actual_subtype;
245         ff_asf_guid actual_formattype;
246
247         if (size < 32) {
248             av_log(s, AV_LOG_WARNING, "format buffer size underflow\n");
249             url_fskip(pb, size);
250             return NULL;
251         }
252
253         url_fskip(pb, size - 32);
254         ff_get_guid(pb, &actual_subtype);
255         ff_get_guid(pb, &actual_formattype);
256         url_fseek(pb, -size, SEEK_CUR);
257
258         st = parse_media_type(s, st, sid, mediatype, actual_subtype, actual_formattype, size - 32);
259         url_fskip(pb, 32);
260         return st;
261     } else if (!ff_guidcmp(mediatype, mediatype_audio)) {
262         st = new_stream(s, st, sid, AVMEDIA_TYPE_AUDIO);
263         if (!st)
264             return NULL;
265         if (!ff_guidcmp(formattype, format_waveformatex)) {
266             ff_get_wav_header(pb, st->codec, size);
267         } else {
268             if (ff_guidcmp(formattype, format_none))
269                 av_log(s, AV_LOG_WARNING, "unknown formattype:"PRI_GUID"\n", ARG_GUID(formattype));
270             url_fskip(pb, size);
271         }
272
273         if (!memcmp(subtype + 4, (const uint8_t[]){MEDIASUBTYPE_BASE_GUID}, 12)) {
274             st->codec->codec_id = ff_wav_codec_get_id(AV_RL32(subtype), st->codec->bits_per_coded_sample);
275         } else if (!ff_guidcmp(subtype, mediasubtype_mpeg1payload)) {
276             if (st->codec->extradata && st->codec->extradata_size >= 22)
277                 parse_mpeg1waveformatex(st);
278             else
279                 av_log(s, AV_LOG_WARNING, "MPEG1WAVEFORMATEX underflow\n");
280         } else {
281             st->codec->codec_id = ff_codec_guid_get_id(audio_guids, subtype);
282             if (st->codec->codec_id == CODEC_ID_NONE)
283                 av_log(s, AV_LOG_WARNING, "unknown subtype:"PRI_GUID"\n", ARG_GUID(subtype));
284         }
285         return st;
286     } else if (!ff_guidcmp(mediatype, mediatype_video)) {
287         st = new_stream(s, st, sid, AVMEDIA_TYPE_VIDEO);
288         if (!st)
289             return NULL;
290         if (!ff_guidcmp(formattype, format_videoinfo2)) {
291             int consumed = parse_videoinfoheader2(s, st);
292             url_fskip(pb, FFMAX(size - consumed, 0));
293         } else if (!ff_guidcmp(formattype, format_mpeg2_video)) {
294             int consumed = parse_videoinfoheader2(s, st);
295             url_fskip(pb, FFMAX(size - consumed, 0));
296         } else {
297             if (ff_guidcmp(formattype, format_none))
298                 av_log(s, AV_LOG_WARNING, "unknown formattype:"PRI_GUID"\n", ARG_GUID(formattype));
299             url_fskip(pb, size);
300         }
301
302         if (!memcmp(subtype + 4, (const uint8_t[]){MEDIASUBTYPE_BASE_GUID}, 12)) {
303             st->codec->codec_id = ff_codec_get_id(ff_codec_bmp_tags, AV_RL32(subtype));
304         } else {
305             st->codec->codec_id = ff_codec_guid_get_id(video_guids, subtype);
306         }
307         if (st->codec->codec_id == CODEC_ID_NONE)
308             av_log(s, AV_LOG_WARNING, "unknown subtype:"PRI_GUID"\n", ARG_GUID(subtype));
309         return st;
310     } else if (!ff_guidcmp(mediatype, mediatype_mpeg2_pes) &&
311                !ff_guidcmp(subtype, mediasubtype_dvb_subtitle)) {
312         st = new_stream(s, st, sid, AVMEDIA_TYPE_SUBTITLE);
313         if (!st)
314             return NULL;
315         if (ff_guidcmp(formattype, format_none))
316             av_log(s, AV_LOG_WARNING, "unknown formattype:"PRI_GUID"\n", ARG_GUID(formattype));
317         url_fskip(pb, size);
318         st->codec->codec_id = CODEC_ID_DVB_SUBTITLE;
319         return st;
320     } else if (!ff_guidcmp(mediatype, mediatype_mstvcaption) &&
321                (!ff_guidcmp(subtype, mediasubtype_teletext) || !ff_guidcmp(subtype, mediasubtype_dtvccdata))) {
322         st = new_stream(s, st, sid, AVMEDIA_TYPE_SUBTITLE);
323         if (!st)
324             return NULL;
325         if (ff_guidcmp(formattype, format_none))
326             av_log(s, AV_LOG_WARNING, "unknown formattype:"PRI_GUID"\n", ARG_GUID(formattype));
327         url_fskip(pb, size);
328         st->codec->codec_id   = CODEC_ID_DVB_TELETEXT;
329         return st;
330     } else if (!ff_guidcmp(mediatype, mediatype_mpeg2_sections) &&
331                !ff_guidcmp(subtype, mediasubtype_mpeg2_sections)) {
332         if (ff_guidcmp(formattype, format_none))
333             av_log(s, AV_LOG_WARNING, "unknown formattype:"PRI_GUID"\n", ARG_GUID(formattype));
334         url_fskip(pb, size);
335         return NULL;
336     }
337
338     av_log(s, AV_LOG_WARNING, "unknown media type, mediatype:"PRI_GUID
339                               ", subtype:"PRI_GUID", formattype:"PRI_GUID"\n",
340                               ARG_GUID(mediatype), ARG_GUID(subtype), ARG_GUID(formattype));
341     url_fskip(pb, size);
342     return NULL;
343 }
344
345 enum {
346     SEEK_TO_DATA = 0,
347     SEEK_TO_BYTE,
348     SEEK_TO_PTS,
349 };
350
351 /**
352  * Parse WTV chunks
353  * @param mode SEEK_TO_DATA, SEEK_TO_BYTE, SEEK_TO_PTS
354  * @param seekts either byte position or timestamp
355  * @param[out] len Length of data chunk
356  * @return stream index of data chunk, or <0 on error
357  */
358 static int parse_chunks(AVFormatContext *s, int mode, int64_t seekts, int *len_ptr)
359 {
360     WtvContext *wtv = s->priv_data;
361     ByteIOContext *pb = s->pb;
362     while (!url_feof(pb)) {
363         ff_asf_guid g;
364         int len, sid, consumed;
365
366         if (mode == SEEK_TO_BYTE && url_ftell(pb) >= seekts)
367             return 0;
368
369         ff_get_guid(pb, &g);
370         if (is_zero(g, sizeof(ff_asf_guid)))
371             return AVERROR_EOF;
372
373         len = get_le32(pb);
374         if (len < 32)
375             break;
376         sid = get_le32(pb) & 0x7FFF;
377         url_fskip(pb, 8);
378         consumed = 32;
379
380         if (!ff_guidcmp(g, stream_guid)) {
381             if (ff_find_stream_index(s, sid) < 0) {
382                 ff_asf_guid mediatype, subtype, formattype;
383                 int size;
384                 consumed += 20;
385                 url_fskip(pb, 16);
386                 if (get_le32(pb)) {
387                     url_fskip(pb, 8);
388                     ff_get_guid(pb, &mediatype);
389                     ff_get_guid(pb, &subtype);
390                     url_fskip(pb, 12);
391                     ff_get_guid(pb, &formattype);
392                     size = get_le32(pb);
393                     parse_media_type(s, 0, sid, mediatype, subtype, formattype, size);
394                     consumed += 72 + size;
395                 }
396             }
397         } else if (!ff_guidcmp(g, stream2_guid)) {
398             int stream_index = ff_find_stream_index(s, sid);
399             if (stream_index >= 0 && !((WtvStream*)s->streams[stream_index]->priv_data)->seen_data) {
400                 ff_asf_guid mediatype, subtype, formattype;
401                 int size;
402                 url_fskip(pb, 12);
403                 ff_get_guid(pb, &mediatype);
404                 ff_get_guid(pb, &subtype);
405                 url_fskip(pb, 12);
406                 ff_get_guid(pb, &formattype);
407                 size = get_le32(pb);
408                 parse_media_type(s, s->streams[stream_index], sid, mediatype, subtype, formattype, size);
409                 consumed += 76 + size;
410             }
411         } else if (!ff_guidcmp(g, EVENTID_AudioDescriptorSpanningEvent) ||
412                    !ff_guidcmp(g, EVENTID_CtxADescriptorSpanningEvent) ||
413                    !ff_guidcmp(g, EVENTID_CSDescriptorSpanningEvent) ||
414                    !ff_guidcmp(g, EVENTID_StreamIDSpanningEvent) ||
415                    !ff_guidcmp(g, EVENTID_SubtitleSpanningEvent) ||
416                    !ff_guidcmp(g, EVENTID_TeletextSpanningEvent)) {
417             int stream_index = ff_find_stream_index(s, sid);
418             if (stream_index >= 0) {
419                 AVStream *st = s->streams[stream_index];
420                 uint8_t buf[258];
421                 const uint8_t *pbuf = buf;
422                 int buf_size;
423
424                 url_fskip(pb, 8);
425                 consumed += 8;
426                 if (!ff_guidcmp(g, EVENTID_CtxADescriptorSpanningEvent) ||
427                     !ff_guidcmp(g, EVENTID_CSDescriptorSpanningEvent)) {
428                     url_fskip(pb, 6);
429                     consumed += 6;
430                 }
431
432                 buf_size = FFMIN(len - consumed, sizeof(buf));
433                 get_buffer(pb, buf, buf_size);
434                 consumed += buf_size;
435                 ff_parse_mpeg2_descriptor(s, st, 0, &pbuf, buf + buf_size, 0, 0, 0, 0);
436             }
437         } else if (!ff_guidcmp(g, EVENTID_DVBScramblingControlSpanningEvent)) {
438             int stream_index = ff_find_stream_index(s, sid);
439             if (stream_index >= 0) {
440                 url_fskip(pb, 12);
441                 if (get_le32(pb))
442                     av_log(s, AV_LOG_WARNING, "DVB scrambled stream detected (st:%d), decoding will likely fail\n", stream_index);
443                 consumed += 16;
444             }
445         } else if (!ff_guidcmp(g, EVENTID_LanguageSpanningEvent)) {
446             int stream_index = ff_find_stream_index(s, sid);
447             if (stream_index >= 0) {
448                 AVStream *st = s->streams[stream_index];
449                 uint8_t language[4];
450                 url_fskip(pb, 12);
451                 get_buffer(pb, language, 3);
452                 if (language[0]) {
453                     language[3] = 0;
454                     av_metadata_set2(&st->metadata, "language", language, 0);
455                 }
456                 consumed += 15;
457             }
458         } else if (!ff_guidcmp(g, timestamp_guid)) {
459             url_fskip(pb, 8);
460             wtv->pts = get_le64(pb);
461             consumed += 16;
462             if (wtv->pts == -1)
463                 wtv->pts = AV_NOPTS_VALUE;
464             if (mode == SEEK_TO_PTS && wtv->pts >= seekts) {
465 #define WTV_PAD8(x) (((x) + 7) & ~7)
466                 url_fskip(pb, WTV_PAD8(len) - consumed);
467                 return 0;
468             }
469         } else if (!ff_guidcmp(g, data_guid)) {
470             int stream_index = ff_find_stream_index(s, sid);
471             if (mode == SEEK_TO_DATA && stream_index >= 0) {
472                 WtvStream *wst = s->streams[stream_index]->priv_data;
473                 wst->seen_data = 1;
474                 if (len_ptr) {
475                     *len_ptr = len;
476                 }
477                 if (wtv->pts != AV_NOPTS_VALUE)
478                     av_add_index_entry(s->streams[stream_index], url_ftell(pb) - consumed, wtv->pts, 0, 0, AVINDEX_KEYFRAME);
479                 return stream_index;
480             }
481         } else if (
482             !ff_guidcmp(g, /* DSATTRIB_CAPTURE_STREAMTIME */ (const ff_asf_guid){0x14,0x56,0x1A,0x0C,0xCD,0x30,0x40,0x4F,0xBC,0xBF,0xD0,0x3E,0x52,0x30,0x62,0x07}) ||
483             !ff_guidcmp(g, /* DSATTRIB_PicSampleSeq */ (const ff_asf_guid){0x02,0xAE,0x5B,0x2F,0x8F,0x7B,0x60,0x4F,0x82,0xD6,0xE4,0xEA,0x2F,0x1F,0x4C,0x99}) ||
484             !ff_guidcmp(g, /* DSATTRIB_TRANSPORT_PROPERTIES */ (const ff_asf_guid){0x12,0xF6,0x22,0xB6,0xAD,0x47,0x71,0x46,0xAD,0x6C,0x05,0xA9,0x8E,0x65,0xDE,0x3A}) ||
485             !ff_guidcmp(g, /* dvr_ms_vid_frame_rep_data */ (const ff_asf_guid){0xCC,0x32,0x64,0xDD,0x29,0xE2,0xDB,0x40,0x80,0xF6,0xD2,0x63,0x28,0xD2,0x76,0x1F}) ||
486             !ff_guidcmp(g, /* EVENTID_AudioTypeSpanningEvent */ (const ff_asf_guid){0xBE,0xBF,0x1C,0x50,0x49,0xB8,0xCE,0x42,0x9B,0xE9,0x3D,0xB8,0x69,0xFB,0x82,0xB3}) ||
487             !ff_guidcmp(g, /* EVENTID_ChannelChangeSpanningEvent */ (const ff_asf_guid){0xE5,0xC5,0x67,0x90,0x5C,0x4C,0x05,0x42,0x86,0xC8,0x7A,0xFE,0x20,0xFE,0x1E,0xFA}) ||
488             !ff_guidcmp(g, /* EVENTID_ChannelInfoSpanningEvent */ (const ff_asf_guid){0x80,0x6D,0xF3,0x41,0x32,0x41,0xC2,0x4C,0xB1,0x21,0x01,0xA4,0x32,0x19,0xD8,0x1B}) ||
489             !ff_guidcmp(g, /* EVENTID_ChannelTypeSpanningEvent */ (const ff_asf_guid){0x51,0x1D,0xAB,0x72,0xD2,0x87,0x9B,0x48,0xBA,0x11,0x0E,0x08,0xDC,0x21,0x02,0x43}) ||
490             !ff_guidcmp(g, /* EVENTID_PIDListSpanningEvent */ (const ff_asf_guid){0x65,0x8F,0xFC,0x47,0xBB,0xE2,0x34,0x46,0x9C,0xEF,0xFD,0xBF,0xE6,0x26,0x1D,0x5C}) ||
491             !ff_guidcmp(g, /* EVENTID_SignalAndServiceStatusSpanningEvent */ (const ff_asf_guid){0xCB,0xC5,0x68,0x80,0x04,0x3C,0x2B,0x49,0xB4,0x7D,0x03,0x08,0x82,0x0D,0xCE,0x51}) ||
492             !ff_guidcmp(g, /* EVENTID_StreamTypeSpanningEvent */ (const ff_asf_guid){0xBC,0x2E,0xAF,0x82,0xA6,0x30,0x64,0x42,0xA8,0x0B,0xAD,0x2E,0x13,0x72,0xAC,0x60}) ||
493             !ff_guidcmp(g, (const ff_asf_guid){0x1E,0xBE,0xC3,0xC5,0x43,0x92,0xDC,0x11,0x85,0xE5,0x00,0x12,0x3F,0x6F,0x73,0xB9}) ||
494             !ff_guidcmp(g, (const ff_asf_guid){0x3B,0x86,0xA2,0xB1,0xEB,0x1E,0xC3,0x44,0x8C,0x88,0x1C,0xA3,0xFF,0xE3,0xE7,0x6A}) ||
495             !ff_guidcmp(g, (const ff_asf_guid){0x4E,0x7F,0x4C,0x5B,0xC4,0xD0,0x38,0x4B,0xA8,0x3E,0x21,0x7F,0x7B,0xBF,0x52,0xE7}) ||
496             !ff_guidcmp(g, (const ff_asf_guid){0x63,0x36,0xEB,0xFE,0xA1,0x7E,0xD9,0x11,0x83,0x08,0x00,0x07,0xE9,0x5E,0xAD,0x8D}) ||
497             !ff_guidcmp(g, (const ff_asf_guid){0x70,0xE9,0xF1,0xF8,0x89,0xA4,0x4C,0x4D,0x83,0x73,0xB8,0x12,0xE0,0xD5,0xF8,0x1E}) ||
498             !ff_guidcmp(g, (const ff_asf_guid){0x96,0xC3,0xD2,0xC2,0x7E,0x9A,0xDA,0x11,0x8B,0xF7,0x00,0x07,0xE9,0x5E,0xAD,0x8D}) ||
499             !ff_guidcmp(g, (const ff_asf_guid){0x97,0xC3,0xD2,0xC2,0x7E,0x9A,0xDA,0x11,0x8B,0xF7,0x00,0x07,0xE9,0x5E,0xAD,0x8D}) ||
500             !ff_guidcmp(g, (const ff_asf_guid){0xA1,0xC3,0xD2,0xC2,0x7E,0x9A,0xDA,0x11,0x8B,0xF7,0x00,0x07,0xE9,0x5E,0xAD,0x8D})) {
501             //ignore known guids
502         } else
503             av_log(s, AV_LOG_WARNING, "unsupported chunk:"PRI_GUID"\n", ARG_GUID(g));
504
505         url_fskip(pb, WTV_PAD8(len) - consumed);
506     }
507     return AVERROR_EOF;
508 }
509
510 #define WTV_CHUNK_START 0x40000
511
512 static int read_header(AVFormatContext *s, AVFormatParameters *ap)
513 {
514     ByteIOContext *pb = s->pb;
515     int ret;
516
517     url_fseek(pb, WTV_CHUNK_START, SEEK_SET);
518     ret = parse_chunks(s, SEEK_TO_DATA, 0, 0);
519     if (ret < 0)
520         return ret;
521
522     url_fseek(pb, -32, SEEK_CUR);
523     return 0;
524 }
525
526 static int read_packet(AVFormatContext *s, AVPacket *pkt)
527 {
528     WtvContext *wtv = s->priv_data;
529     ByteIOContext *pb = s->pb;
530     int stream_index, len, ret;
531
532     stream_index = parse_chunks(s, SEEK_TO_DATA, 0, &len);
533     if (stream_index < 0)
534         return stream_index;
535
536     ret = av_get_packet(pb, pkt, len - 32);
537     if (ret < 0)
538         return ret;
539     pkt->stream_index = stream_index;
540     pkt->pts          = wtv->pts;
541     url_fskip(pb, WTV_PAD8(len) - len);
542     return 0;
543 }
544
545 static int read_seek2(AVFormatContext *s, int stream_index,
546                       int64_t min_ts, int64_t ts, int64_t max_ts, int flags)
547 {
548     WtvContext *wtv = s->priv_data;
549     ByteIOContext *pb = s->pb;
550     AVStream *st;
551     int i;
552
553     if (stream_index < 0) {
554         stream_index = av_find_default_stream_index(s);
555         if (stream_index < 0)
556             return -1;
557     }
558     st = s->streams[stream_index];
559
560     if ((flags & AVSEEK_FLAG_FRAME)) {
561         return AVERROR_NOTSUPP;
562     } else if ((flags & AVSEEK_FLAG_BYTE)) {
563         if (ts < url_ftell(pb)) {
564             for (i = st->nb_index_entries - 1; i >= 0; i--) {
565                 if (st->index_entries[i].pos <= ts) {
566                     wtv->pts    = st->index_entries[i].timestamp;
567                     url_fseek(pb, st->index_entries[i].pos, SEEK_SET);
568                     break;
569                 }
570             }
571             if (i < 0) {
572                 wtv->pts = 0;
573                 url_fseek(pb, WTV_CHUNK_START, SEEK_SET);
574             }
575         }
576         if (parse_chunks(s, SEEK_TO_BYTE, ts, 0) < 0)
577             return AVERROR(ERANGE);
578         return 0;
579     } else {
580         ts *= 10;
581         i = av_index_search_timestamp(st, ts, flags);
582         if (i < 0) {
583             if (st->nb_index_entries > 0) {
584                 wtv->pts    = st->index_entries[st->nb_index_entries - 1].timestamp;
585                 url_fseek(pb, st->index_entries[st->nb_index_entries - 1].pos, SEEK_SET);
586             } else {
587                 wtv->pts = 0;
588                 url_fseek(pb, WTV_CHUNK_START, SEEK_SET);
589             }
590             if (parse_chunks(s, SEEK_TO_PTS, ts, 0) < 0)
591                 return AVERROR(ERANGE);
592             return 0;
593         }
594         wtv->pts    = st->index_entries[i].timestamp;
595         url_fseek(pb, st->index_entries[i].pos, SEEK_SET);
596         return 0;
597     }
598 }
599
600 AVInputFormat wtv_demuxer = {
601     .name           = "wtv",
602     .long_name      = NULL_IF_CONFIG_SMALL("Windows Television (WTV)"),
603     .priv_data_size = sizeof(WtvContext),
604     .read_probe     = read_probe,
605     .read_header    = read_header,
606     .read_packet    = read_packet,
607     .read_seek2     = read_seek2,
608     .flags          = AVFMT_SHOW_IDS|AVFMT_TS_DISCONT,
609 };