matroskadec: prevent seeking before the first keyframe of the reference stream
[ffmpeg.git] / libavformat / matroskadec.c
1 /*
2  * Matroska file demuxer
3  * Copyright (c) 2003-2008 The FFmpeg Project
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 matroskadec.c
24  * Matroska file demuxer
25  * by Ronald Bultje <rbultje@ronald.bitfreak.net>
26  * with a little help from Moritz Bunkus <moritz@bunkus.org>
27  * totally reworked by Aurelien Jacobs <aurel@gnuage.org>
28  * Specs available on the Matroska project page: http://www.matroska.org/.
29  */
30
31 #include <stdio.h>
32 #include "avformat.h"
33 /* For codec_get_id(). */
34 #include "riff.h"
35 #include "isom.h"
36 #include "matroska.h"
37 #include "libavcodec/mpeg4audio.h"
38 #include "libavutil/intfloat_readwrite.h"
39 #include "libavutil/avstring.h"
40 #include "libavutil/lzo.h"
41 #ifdef CONFIG_ZLIB
42 #include <zlib.h>
43 #endif
44 #ifdef CONFIG_BZLIB
45 #include <bzlib.h>
46 #endif
47
48 typedef enum {
49     EBML_NONE,
50     EBML_UINT,
51     EBML_FLOAT,
52     EBML_STR,
53     EBML_UTF8,
54     EBML_BIN,
55     EBML_NEST,
56     EBML_PASS,
57     EBML_STOP,
58 } EbmlType;
59
60 typedef const struct EbmlSyntax {
61     uint32_t id;
62     EbmlType type;
63     int list_elem_size;
64     int data_offset;
65     union {
66         uint64_t    u;
67         double      f;
68         const char *s;
69         const struct EbmlSyntax *n;
70     } def;
71 } EbmlSyntax;
72
73 typedef struct {
74     int nb_elem;
75     void *elem;
76 } EbmlList;
77
78 typedef struct {
79     int      size;
80     uint8_t *data;
81     int64_t  pos;
82 } EbmlBin;
83
84 typedef struct {
85     uint64_t version;
86     uint64_t max_size;
87     uint64_t id_length;
88     char    *doctype;
89     uint64_t doctype_version;
90 } Ebml;
91
92 typedef struct {
93     uint64_t algo;
94     EbmlBin  settings;
95 } MatroskaTrackCompression;
96
97 typedef struct {
98     uint64_t scope;
99     uint64_t type;
100     MatroskaTrackCompression compression;
101 } MatroskaTrackEncoding;
102
103 typedef struct {
104     double   frame_rate;
105     uint64_t display_width;
106     uint64_t display_height;
107     uint64_t pixel_width;
108     uint64_t pixel_height;
109     uint64_t fourcc;
110 } MatroskaTrackVideo;
111
112 typedef struct {
113     double   samplerate;
114     double   out_samplerate;
115     uint64_t bitdepth;
116     uint64_t channels;
117
118     /* real audio header (extracted from extradata) */
119     int      coded_framesize;
120     int      sub_packet_h;
121     int      frame_size;
122     int      sub_packet_size;
123     int      sub_packet_cnt;
124     int      pkt_cnt;
125     uint8_t *buf;
126 } MatroskaTrackAudio;
127
128 typedef struct {
129     uint64_t num;
130     uint64_t type;
131     char    *codec_id;
132     EbmlBin  codec_priv;
133     char    *language;
134     double time_scale;
135     uint64_t default_duration;
136     uint64_t flag_default;
137     MatroskaTrackVideo video;
138     MatroskaTrackAudio audio;
139     EbmlList encodings;
140
141     AVStream *stream;
142     int64_t first_timecode;
143     int64_t end_timecode;
144 } MatroskaTrack;
145
146 typedef struct {
147     char *filename;
148     char *mime;
149     EbmlBin bin;
150 } MatroskaAttachement;
151
152 typedef struct {
153     uint64_t start;
154     uint64_t end;
155     uint64_t uid;
156     char    *title;
157 } MatroskaChapter;
158
159 typedef struct {
160     uint64_t track;
161     uint64_t pos;
162 } MatroskaIndexPos;
163
164 typedef struct {
165     uint64_t time;
166     EbmlList pos;
167 } MatroskaIndex;
168
169 typedef struct {
170     char *name;
171     char *string;
172     EbmlList sub;
173 } MatroskaTag;
174
175 typedef struct {
176     uint64_t id;
177     uint64_t pos;
178 } MatroskaSeekhead;
179
180 typedef struct {
181     uint64_t start;
182     uint64_t length;
183 } MatroskaLevel;
184
185 typedef struct {
186     AVFormatContext *ctx;
187
188     /* EBML stuff */
189     int num_levels;
190     MatroskaLevel levels[EBML_MAX_DEPTH];
191     int level_up;
192
193     uint64_t time_scale;
194     double   duration;
195     char    *title;
196     EbmlList tracks;
197     EbmlList attachments;
198     EbmlList chapters;
199     EbmlList index;
200     EbmlList tags;
201     EbmlList seekhead;
202
203     /* byte position of the segment inside the stream */
204     offset_t segment_start;
205
206     /* the packet queue */
207     AVPacket **packets;
208     int num_packets;
209
210     int done;
211     int has_cluster_id;
212
213     /* What to skip before effectively reading a packet. */
214     int skip_to_keyframe;
215     uint64_t skip_to_timecode;
216 } MatroskaDemuxContext;
217
218 typedef struct {
219     uint64_t duration;
220     int64_t  reference;
221     EbmlBin  bin;
222 } MatroskaBlock;
223
224 typedef struct {
225     uint64_t timecode;
226     EbmlList blocks;
227 } MatroskaCluster;
228
229 #define ARRAY_SIZE(x)  (sizeof(x)/sizeof(*x))
230
231 static EbmlSyntax ebml_header[] = {
232     { EBML_ID_EBMLREADVERSION,        EBML_UINT, 0, offsetof(Ebml,version), {.u=EBML_VERSION} },
233     { EBML_ID_EBMLMAXSIZELENGTH,      EBML_UINT, 0, offsetof(Ebml,max_size), {.u=8} },
234     { EBML_ID_EBMLMAXIDLENGTH,        EBML_UINT, 0, offsetof(Ebml,id_length), {.u=4} },
235     { EBML_ID_DOCTYPE,                EBML_STR,  0, offsetof(Ebml,doctype), {.s="(none)"} },
236     { EBML_ID_DOCTYPEREADVERSION,     EBML_UINT, 0, offsetof(Ebml,doctype_version), {.u=1} },
237     { EBML_ID_EBMLVERSION,            EBML_NONE },
238     { EBML_ID_DOCTYPEVERSION,         EBML_NONE },
239     { 0 }
240 };
241
242 static EbmlSyntax ebml_syntax[] = {
243     { EBML_ID_HEADER,                 EBML_NEST, 0, 0, {.n=ebml_header} },
244     { 0 }
245 };
246
247 static EbmlSyntax matroska_info[] = {
248     { MATROSKA_ID_TIMECODESCALE,      EBML_UINT,  0, offsetof(MatroskaDemuxContext,time_scale), {.u=1000000} },
249     { MATROSKA_ID_DURATION,           EBML_FLOAT, 0, offsetof(MatroskaDemuxContext,duration) },
250     { MATROSKA_ID_TITLE,              EBML_UTF8,  0, offsetof(MatroskaDemuxContext,title) },
251     { MATROSKA_ID_WRITINGAPP,         EBML_NONE },
252     { MATROSKA_ID_MUXINGAPP,          EBML_NONE },
253     { MATROSKA_ID_DATEUTC,            EBML_NONE },
254     { MATROSKA_ID_SEGMENTUID,         EBML_NONE },
255     { 0 }
256 };
257
258 static EbmlSyntax matroska_track_video[] = {
259     { MATROSKA_ID_VIDEOFRAMERATE,     EBML_FLOAT,0, offsetof(MatroskaTrackVideo,frame_rate) },
260     { MATROSKA_ID_VIDEODISPLAYWIDTH,  EBML_UINT, 0, offsetof(MatroskaTrackVideo,display_width) },
261     { MATROSKA_ID_VIDEODISPLAYHEIGHT, EBML_UINT, 0, offsetof(MatroskaTrackVideo,display_height) },
262     { MATROSKA_ID_VIDEOPIXELWIDTH,    EBML_UINT, 0, offsetof(MatroskaTrackVideo,pixel_width) },
263     { MATROSKA_ID_VIDEOPIXELHEIGHT,   EBML_UINT, 0, offsetof(MatroskaTrackVideo,pixel_height) },
264     { MATROSKA_ID_VIDEOCOLORSPACE,    EBML_UINT, 0, offsetof(MatroskaTrackVideo,fourcc) },
265     { MATROSKA_ID_VIDEOPIXELCROPB,    EBML_NONE },
266     { MATROSKA_ID_VIDEOPIXELCROPT,    EBML_NONE },
267     { MATROSKA_ID_VIDEOPIXELCROPL,    EBML_NONE },
268     { MATROSKA_ID_VIDEOPIXELCROPR,    EBML_NONE },
269     { MATROSKA_ID_VIDEODISPLAYUNIT,   EBML_NONE },
270     { MATROSKA_ID_VIDEOFLAGINTERLACED,EBML_NONE },
271     { MATROSKA_ID_VIDEOSTEREOMODE,    EBML_NONE },
272     { MATROSKA_ID_VIDEOASPECTRATIO,   EBML_NONE },
273     { 0 }
274 };
275
276 static EbmlSyntax matroska_track_audio[] = {
277     { MATROSKA_ID_AUDIOSAMPLINGFREQ,  EBML_FLOAT,0, offsetof(MatroskaTrackAudio,samplerate), {.f=8000.0} },
278     { MATROSKA_ID_AUDIOOUTSAMPLINGFREQ,EBML_FLOAT,0,offsetof(MatroskaTrackAudio,out_samplerate) },
279     { MATROSKA_ID_AUDIOBITDEPTH,      EBML_UINT, 0, offsetof(MatroskaTrackAudio,bitdepth) },
280     { MATROSKA_ID_AUDIOCHANNELS,      EBML_UINT, 0, offsetof(MatroskaTrackAudio,channels), {.u=1} },
281     { 0 }
282 };
283
284 static EbmlSyntax matroska_track_encoding_compression[] = {
285     { MATROSKA_ID_ENCODINGCOMPALGO,   EBML_UINT, 0, offsetof(MatroskaTrackCompression,algo), {.u=0} },
286     { MATROSKA_ID_ENCODINGCOMPSETTINGS,EBML_BIN, 0, offsetof(MatroskaTrackCompression,settings) },
287     { 0 }
288 };
289
290 static EbmlSyntax matroska_track_encoding[] = {
291     { MATROSKA_ID_ENCODINGSCOPE,      EBML_UINT, 0, offsetof(MatroskaTrackEncoding,scope), {.u=1} },
292     { MATROSKA_ID_ENCODINGTYPE,       EBML_UINT, 0, offsetof(MatroskaTrackEncoding,type), {.u=0} },
293     { MATROSKA_ID_ENCODINGCOMPRESSION,EBML_NEST, 0, offsetof(MatroskaTrackEncoding,compression), {.n=matroska_track_encoding_compression} },
294     { MATROSKA_ID_ENCODINGORDER,      EBML_NONE },
295     { 0 }
296 };
297
298 static EbmlSyntax matroska_track_encodings[] = {
299     { MATROSKA_ID_TRACKCONTENTENCODING, EBML_NEST, sizeof(MatroskaTrackEncoding), offsetof(MatroskaTrack,encodings), {.n=matroska_track_encoding} },
300     { 0 }
301 };
302
303 static EbmlSyntax matroska_track[] = {
304     { MATROSKA_ID_TRACKNUMBER,          EBML_UINT, 0, offsetof(MatroskaTrack,num) },
305     { MATROSKA_ID_TRACKTYPE,            EBML_UINT, 0, offsetof(MatroskaTrack,type) },
306     { MATROSKA_ID_CODECID,              EBML_STR,  0, offsetof(MatroskaTrack,codec_id) },
307     { MATROSKA_ID_CODECPRIVATE,         EBML_BIN,  0, offsetof(MatroskaTrack,codec_priv) },
308     { MATROSKA_ID_TRACKLANGUAGE,        EBML_UTF8, 0, offsetof(MatroskaTrack,language), {.s="eng"} },
309     { MATROSKA_ID_TRACKDEFAULTDURATION, EBML_UINT, 0, offsetof(MatroskaTrack,default_duration) },
310     { MATROSKA_ID_TRACKTIMECODESCALE,   EBML_FLOAT,0, offsetof(MatroskaTrack,time_scale), {.f=1.0} },
311     { MATROSKA_ID_TRACKFLAGDEFAULT,     EBML_UINT, 0, offsetof(MatroskaTrack,flag_default), {.u=1} },
312     { MATROSKA_ID_TRACKVIDEO,           EBML_NEST, 0, offsetof(MatroskaTrack,video), {.n=matroska_track_video} },
313     { MATROSKA_ID_TRACKAUDIO,           EBML_NEST, 0, offsetof(MatroskaTrack,audio), {.n=matroska_track_audio} },
314     { MATROSKA_ID_TRACKCONTENTENCODINGS,EBML_NEST, 0, 0, {.n=matroska_track_encodings} },
315     { MATROSKA_ID_TRACKUID,             EBML_NONE },
316     { MATROSKA_ID_TRACKNAME,            EBML_NONE },
317     { MATROSKA_ID_TRACKFLAGENABLED,     EBML_NONE },
318     { MATROSKA_ID_TRACKFLAGFORCED,      EBML_NONE },
319     { MATROSKA_ID_TRACKFLAGLACING,      EBML_NONE },
320     { MATROSKA_ID_CODECNAME,            EBML_NONE },
321     { MATROSKA_ID_CODECDECODEALL,       EBML_NONE },
322     { MATROSKA_ID_CODECINFOURL,         EBML_NONE },
323     { MATROSKA_ID_CODECDOWNLOADURL,     EBML_NONE },
324     { MATROSKA_ID_TRACKMINCACHE,        EBML_NONE },
325     { MATROSKA_ID_TRACKMAXCACHE,        EBML_NONE },
326     { MATROSKA_ID_TRACKMAXBLKADDID,     EBML_NONE },
327     { 0 }
328 };
329
330 static EbmlSyntax matroska_tracks[] = {
331     { MATROSKA_ID_TRACKENTRY,         EBML_NEST, sizeof(MatroskaTrack), offsetof(MatroskaDemuxContext,tracks), {.n=matroska_track} },
332     { 0 }
333 };
334
335 static EbmlSyntax matroska_attachment[] = {
336     { MATROSKA_ID_FILENAME,           EBML_UTF8, 0, offsetof(MatroskaAttachement,filename) },
337     { MATROSKA_ID_FILEMIMETYPE,       EBML_STR,  0, offsetof(MatroskaAttachement,mime) },
338     { MATROSKA_ID_FILEDATA,           EBML_BIN,  0, offsetof(MatroskaAttachement,bin) },
339     { MATROSKA_ID_FILEDESC,           EBML_NONE },
340     { MATROSKA_ID_FILEUID,            EBML_NONE },
341     { 0 }
342 };
343
344 static EbmlSyntax matroska_attachments[] = {
345     { MATROSKA_ID_ATTACHEDFILE,       EBML_NEST, sizeof(MatroskaAttachement), offsetof(MatroskaDemuxContext,attachments), {.n=matroska_attachment} },
346     { 0 }
347 };
348
349 static EbmlSyntax matroska_chapter_display[] = {
350     { MATROSKA_ID_CHAPSTRING,         EBML_UTF8, 0, offsetof(MatroskaChapter,title) },
351     { MATROSKA_ID_CHAPLANG,           EBML_NONE },
352     { 0 }
353 };
354
355 static EbmlSyntax matroska_chapter_entry[] = {
356     { MATROSKA_ID_CHAPTERTIMESTART,   EBML_UINT, 0, offsetof(MatroskaChapter,start), {.u=AV_NOPTS_VALUE} },
357     { MATROSKA_ID_CHAPTERTIMEEND,     EBML_UINT, 0, offsetof(MatroskaChapter,end), {.u=AV_NOPTS_VALUE} },
358     { MATROSKA_ID_CHAPTERUID,         EBML_UINT, 0, offsetof(MatroskaChapter,uid) },
359     { MATROSKA_ID_CHAPTERDISPLAY,     EBML_NEST, 0, 0, {.n=matroska_chapter_display} },
360     { MATROSKA_ID_CHAPTERFLAGHIDDEN,  EBML_NONE },
361     { MATROSKA_ID_CHAPTERFLAGENABLED, EBML_NONE },
362     { MATROSKA_ID_CHAPTERPHYSEQUIV,   EBML_NONE },
363     { MATROSKA_ID_CHAPTERATOM,        EBML_NONE },
364     { 0 }
365 };
366
367 static EbmlSyntax matroska_chapter[] = {
368     { MATROSKA_ID_CHAPTERATOM,        EBML_NEST, sizeof(MatroskaChapter), offsetof(MatroskaDemuxContext,chapters), {.n=matroska_chapter_entry} },
369     { MATROSKA_ID_EDITIONUID,         EBML_NONE },
370     { MATROSKA_ID_EDITIONFLAGHIDDEN,  EBML_NONE },
371     { MATROSKA_ID_EDITIONFLAGDEFAULT, EBML_NONE },
372     { MATROSKA_ID_EDITIONFLAGORDERED, EBML_NONE },
373     { 0 }
374 };
375
376 static EbmlSyntax matroska_chapters[] = {
377     { MATROSKA_ID_EDITIONENTRY,       EBML_NEST, 0, 0, {.n=matroska_chapter} },
378     { 0 }
379 };
380
381 static EbmlSyntax matroska_index_pos[] = {
382     { MATROSKA_ID_CUETRACK,           EBML_UINT, 0, offsetof(MatroskaIndexPos,track) },
383     { MATROSKA_ID_CUECLUSTERPOSITION, EBML_UINT, 0, offsetof(MatroskaIndexPos,pos)   },
384     { MATROSKA_ID_CUEBLOCKNUMBER,     EBML_NONE },
385     { 0 }
386 };
387
388 static EbmlSyntax matroska_index_entry[] = {
389     { MATROSKA_ID_CUETIME,            EBML_UINT, 0, offsetof(MatroskaIndex,time) },
390     { MATROSKA_ID_CUETRACKPOSITION,   EBML_NEST, sizeof(MatroskaIndexPos), offsetof(MatroskaIndex,pos), {.n=matroska_index_pos} },
391     { 0 }
392 };
393
394 static EbmlSyntax matroska_index[] = {
395     { MATROSKA_ID_POINTENTRY,         EBML_NEST, sizeof(MatroskaIndex), offsetof(MatroskaDemuxContext,index), {.n=matroska_index_entry} },
396     { 0 }
397 };
398
399 static EbmlSyntax matroska_simpletag[] = {
400     { MATROSKA_ID_TAGNAME,            EBML_UTF8, 0, offsetof(MatroskaTag,name) },
401     { MATROSKA_ID_TAGSTRING,          EBML_UTF8, 0, offsetof(MatroskaTag,string) },
402     { MATROSKA_ID_SIMPLETAG,          EBML_NEST, sizeof(MatroskaTag), offsetof(MatroskaTag,sub), {.n=matroska_simpletag} },
403     { MATROSKA_ID_TAGLANG,            EBML_NONE },
404     { MATROSKA_ID_TAGDEFAULT,         EBML_NONE },
405     { 0 }
406 };
407
408 static EbmlSyntax matroska_tag[] = {
409     { MATROSKA_ID_SIMPLETAG,          EBML_NEST, sizeof(MatroskaTag), 0, {.n=matroska_simpletag} },
410     { MATROSKA_ID_TAGTARGETS,         EBML_NONE },
411     { 0 }
412 };
413
414 static EbmlSyntax matroska_tags[] = {
415     { MATROSKA_ID_TAG,                EBML_NEST, 0, offsetof(MatroskaDemuxContext,tags), {.n=matroska_tag} },
416     { 0 }
417 };
418
419 static EbmlSyntax matroska_seekhead_entry[] = {
420     { MATROSKA_ID_SEEKID,             EBML_UINT, 0, offsetof(MatroskaSeekhead,id) },
421     { MATROSKA_ID_SEEKPOSITION,       EBML_UINT, 0, offsetof(MatroskaSeekhead,pos), {.u=-1} },
422     { 0 }
423 };
424
425 static EbmlSyntax matroska_seekhead[] = {
426     { MATROSKA_ID_SEEKENTRY,          EBML_NEST, sizeof(MatroskaSeekhead), offsetof(MatroskaDemuxContext,seekhead), {.n=matroska_seekhead_entry} },
427     { 0 }
428 };
429
430 static EbmlSyntax matroska_segment[] = {
431     { MATROSKA_ID_INFO,           EBML_NEST, 0, 0, {.n=matroska_info       } },
432     { MATROSKA_ID_TRACKS,         EBML_NEST, 0, 0, {.n=matroska_tracks     } },
433     { MATROSKA_ID_ATTACHMENTS,    EBML_NEST, 0, 0, {.n=matroska_attachments} },
434     { MATROSKA_ID_CHAPTERS,       EBML_NEST, 0, 0, {.n=matroska_chapters   } },
435     { MATROSKA_ID_CUES,           EBML_NEST, 0, 0, {.n=matroska_index      } },
436     { MATROSKA_ID_TAGS,           EBML_NEST, 0, 0, {.n=matroska_tags       } },
437     { MATROSKA_ID_SEEKHEAD,       EBML_NEST, 0, 0, {.n=matroska_seekhead   } },
438     { MATROSKA_ID_CLUSTER,        EBML_STOP, 0, offsetof(MatroskaDemuxContext,has_cluster_id) },
439     { 0 }
440 };
441
442 static EbmlSyntax matroska_segments[] = {
443     { MATROSKA_ID_SEGMENT,        EBML_NEST, 0, 0, {.n=matroska_segment    } },
444     { 0 }
445 };
446
447 static EbmlSyntax matroska_blockgroup[] = {
448     { MATROSKA_ID_BLOCK,          EBML_BIN,  0, offsetof(MatroskaBlock,bin) },
449     { MATROSKA_ID_SIMPLEBLOCK,    EBML_BIN,  0, offsetof(MatroskaBlock,bin) },
450     { MATROSKA_ID_BLOCKDURATION,  EBML_UINT, 0, offsetof(MatroskaBlock,duration), {.u=AV_NOPTS_VALUE} },
451     { MATROSKA_ID_BLOCKREFERENCE, EBML_UINT, 0, offsetof(MatroskaBlock,reference) },
452     { 0 }
453 };
454
455 static EbmlSyntax matroska_cluster[] = {
456     { MATROSKA_ID_CLUSTERTIMECODE,EBML_UINT,0, offsetof(MatroskaCluster,timecode) },
457     { MATROSKA_ID_BLOCKGROUP,     EBML_NEST, sizeof(MatroskaBlock), offsetof(MatroskaCluster,blocks), {.n=matroska_blockgroup} },
458     { MATROSKA_ID_SIMPLEBLOCK,    EBML_PASS, sizeof(MatroskaBlock), offsetof(MatroskaCluster,blocks), {.n=matroska_blockgroup} },
459     { MATROSKA_ID_CLUSTERPOSITION,EBML_NONE },
460     { MATROSKA_ID_CLUSTERPREVSIZE,EBML_NONE },
461     { 0 }
462 };
463
464 static EbmlSyntax matroska_clusters[] = {
465     { MATROSKA_ID_CLUSTER,        EBML_NEST, 0, 0, {.n=matroska_cluster} },
466     { MATROSKA_ID_INFO,           EBML_NONE },
467     { MATROSKA_ID_CUES,           EBML_NONE },
468     { MATROSKA_ID_TAGS,           EBML_NONE },
469     { MATROSKA_ID_SEEKHEAD,       EBML_NONE },
470     { 0 }
471 };
472
473 #define SIZE_OFF(x) sizeof(((AVFormatContext*)0)->x),offsetof(AVFormatContext,x)
474 const struct {
475     const char name[16];
476     int   size;
477     int   offset;
478 } metadata[] = {
479     { "TITLE",           SIZE_OFF(title)      },
480     { "ARTIST",          SIZE_OFF(author)     },
481     { "WRITTEN_BY",      SIZE_OFF(author)     },
482     { "LEAD_PERFORMER",  SIZE_OFF(author)     },
483     { "COPYRIGHT",       SIZE_OFF(copyright)  },
484     { "COMMENT",         SIZE_OFF(comment)    },
485     { "ALBUM",           SIZE_OFF(album)      },
486     { "DATE_WRITTEN",    SIZE_OFF(year)       },
487     { "DATE_RELEASED",   SIZE_OFF(year)       },
488     { "PART_NUMBER",     SIZE_OFF(track)      },
489     { "GENRE",           SIZE_OFF(genre)      },
490 };
491
492 /*
493  * Return: Whether we reached the end of a level in the hierarchy or not.
494  */
495 static int ebml_level_end(MatroskaDemuxContext *matroska)
496 {
497     ByteIOContext *pb = matroska->ctx->pb;
498     offset_t pos = url_ftell(pb);
499
500     if (matroska->num_levels > 0) {
501         MatroskaLevel *level = &matroska->levels[matroska->num_levels - 1];
502         if (pos - level->start >= level->length) {
503             matroska->num_levels--;
504             return 1;
505         }
506     }
507     return 0;
508 }
509
510 /*
511  * Read: an "EBML number", which is defined as a variable-length
512  * array of bytes. The first byte indicates the length by giving a
513  * number of 0-bits followed by a one. The position of the first
514  * "one" bit inside the first byte indicates the length of this
515  * number.
516  * Returns: number of bytes read, < 0 on error
517  */
518 static int ebml_read_num(MatroskaDemuxContext *matroska, ByteIOContext *pb,
519                          int max_size, uint64_t *number)
520 {
521     int len_mask = 0x80, read = 1, n = 1;
522     int64_t total = 0;
523
524     /* The first byte tells us the length in bytes - get_byte() can normally
525      * return 0, but since that's not a valid first ebmlID byte, we can
526      * use it safely here to catch EOS. */
527     if (!(total = get_byte(pb))) {
528         /* we might encounter EOS here */
529         if (!url_feof(pb)) {
530             offset_t pos = url_ftell(pb);
531             av_log(matroska->ctx, AV_LOG_ERROR,
532                    "Read error at pos. %"PRIu64" (0x%"PRIx64")\n",
533                    pos, pos);
534         }
535         return AVERROR(EIO); /* EOS or actual I/O error */
536     }
537
538     /* get the length of the EBML number */
539     while (read <= max_size && !(total & len_mask)) {
540         read++;
541         len_mask >>= 1;
542     }
543     if (read > max_size) {
544         offset_t pos = url_ftell(pb) - 1;
545         av_log(matroska->ctx, AV_LOG_ERROR,
546                "Invalid EBML number size tag 0x%02x at pos %"PRIu64" (0x%"PRIx64")\n",
547                (uint8_t) total, pos, pos);
548         return AVERROR_INVALIDDATA;
549     }
550
551     /* read out length */
552     total &= ~len_mask;
553     while (n++ < read)
554         total = (total << 8) | get_byte(pb);
555
556     *number = total;
557
558     return read;
559 }
560
561 /*
562  * Read the next element as an unsigned int.
563  * 0 is success, < 0 is failure.
564  */
565 static int ebml_read_uint(ByteIOContext *pb, int size, uint64_t *num)
566 {
567     int n = 0;
568
569     if (size < 1 || size > 8)
570         return AVERROR_INVALIDDATA;
571
572     /* big-endian ordering; build up number */
573     *num = 0;
574     while (n++ < size)
575         *num = (*num << 8) | get_byte(pb);
576
577     return 0;
578 }
579
580 /*
581  * Read the next element as a float.
582  * 0 is success, < 0 is failure.
583  */
584 static int ebml_read_float(ByteIOContext *pb, int size, double *num)
585 {
586     if (size == 4) {
587         *num= av_int2flt(get_be32(pb));
588     } else if(size==8){
589         *num= av_int2dbl(get_be64(pb));
590     } else
591         return AVERROR_INVALIDDATA;
592
593     return 0;
594 }
595
596 /*
597  * Read the next element as an ASCII string.
598  * 0 is success, < 0 is failure.
599  */
600 static int ebml_read_ascii(ByteIOContext *pb, int size, char **str)
601 {
602     av_free(*str);
603     /* EBML strings are usually not 0-terminated, so we allocate one
604      * byte more, read the string and NULL-terminate it ourselves. */
605     if (!(*str = av_malloc(size + 1)))
606         return AVERROR(ENOMEM);
607     if (get_buffer(pb, (uint8_t *) *str, size) != size) {
608         av_free(*str);
609         return AVERROR(EIO);
610     }
611     (*str)[size] = '\0';
612
613     return 0;
614 }
615
616 /*
617  * Read the next element as binary data.
618  * 0 is success, < 0 is failure.
619  */
620 static int ebml_read_binary(ByteIOContext *pb, int length, EbmlBin *bin)
621 {
622     av_free(bin->data);
623     if (!(bin->data = av_malloc(length)))
624         return AVERROR(ENOMEM);
625
626     bin->size = length;
627     bin->pos  = url_ftell(pb);
628     if (get_buffer(pb, bin->data, length) != length)
629         return AVERROR(EIO);
630
631     return 0;
632 }
633
634 /*
635  * Read the next element, but only the header. The contents
636  * are supposed to be sub-elements which can be read separately.
637  * 0 is success, < 0 is failure.
638  */
639 static int ebml_read_master(MatroskaDemuxContext *matroska, int length)
640 {
641     ByteIOContext *pb = matroska->ctx->pb;
642     MatroskaLevel *level;
643
644     if (matroska->num_levels >= EBML_MAX_DEPTH) {
645         av_log(matroska->ctx, AV_LOG_ERROR,
646                "File moves beyond max. allowed depth (%d)\n", EBML_MAX_DEPTH);
647         return AVERROR(ENOSYS);
648     }
649
650     level = &matroska->levels[matroska->num_levels++];
651     level->start = url_ftell(pb);
652     level->length = length;
653
654     return 0;
655 }
656
657 /*
658  * Read signed/unsigned "EBML" numbers.
659  * Return: number of bytes processed, < 0 on error
660  */
661 static int matroska_ebmlnum_uint(MatroskaDemuxContext *matroska,
662                                  uint8_t *data, uint32_t size, uint64_t *num)
663 {
664     ByteIOContext pb;
665     init_put_byte(&pb, data, size, 0, NULL, NULL, NULL, NULL);
666     return ebml_read_num(matroska, &pb, 8, num);
667 }
668
669 /*
670  * Same as above, but signed.
671  */
672 static int matroska_ebmlnum_sint(MatroskaDemuxContext *matroska,
673                                  uint8_t *data, uint32_t size, int64_t *num)
674 {
675     uint64_t unum;
676     int res;
677
678     /* read as unsigned number first */
679     if ((res = matroska_ebmlnum_uint(matroska, data, size, &unum)) < 0)
680         return res;
681
682     /* make signed (weird way) */
683     *num = unum - ((1LL << (7*res - 1)) - 1);
684
685     return res;
686 }
687
688 static int ebml_parse_elem(MatroskaDemuxContext *matroska,
689                            EbmlSyntax *syntax, void *data);
690
691 static int ebml_parse_id(MatroskaDemuxContext *matroska, EbmlSyntax *syntax,
692                          uint32_t id, void *data)
693 {
694     int i;
695     for (i=0; syntax[i].id; i++)
696         if (id == syntax[i].id)
697             break;
698     if (!syntax[i].id && id != EBML_ID_VOID && id != EBML_ID_CRC32)
699         av_log(matroska->ctx, AV_LOG_INFO, "Unknown entry 0x%X\n", id);
700     return ebml_parse_elem(matroska, &syntax[i], data);
701 }
702
703 static int ebml_parse(MatroskaDemuxContext *matroska, EbmlSyntax *syntax,
704                       void *data)
705 {
706     uint64_t id;
707     int res = ebml_read_num(matroska, matroska->ctx->pb, 4, &id);
708     id |= 1 << 7*res;
709     return res < 0 ? res : ebml_parse_id(matroska, syntax, id, data);
710 }
711
712 static int ebml_parse_nest(MatroskaDemuxContext *matroska, EbmlSyntax *syntax,
713                            void *data)
714 {
715     int i, res = 0;
716
717     for (i=0; syntax[i].id; i++)
718         switch (syntax[i].type) {
719         case EBML_UINT:
720             *(uint64_t *)((char *)data+syntax[i].data_offset) = syntax[i].def.u;
721             break;
722         case EBML_FLOAT:
723             *(double   *)((char *)data+syntax[i].data_offset) = syntax[i].def.f;
724             break;
725         case EBML_STR:
726         case EBML_UTF8:
727             *(char    **)((char *)data+syntax[i].data_offset) = av_strdup(syntax[i].def.s);
728             break;
729         }
730
731     while (!res && !ebml_level_end(matroska))
732         res = ebml_parse(matroska, syntax, data);
733
734     return res;
735 }
736
737 static int ebml_parse_elem(MatroskaDemuxContext *matroska,
738                            EbmlSyntax *syntax, void *data)
739 {
740     ByteIOContext *pb = matroska->ctx->pb;
741     uint32_t id = syntax->id;
742     uint64_t length;
743     int res;
744
745     data = (char *)data + syntax->data_offset;
746     if (syntax->list_elem_size) {
747         EbmlList *list = data;
748         list->elem = av_realloc(list->elem, (list->nb_elem+1)*syntax->list_elem_size);
749         data = (char*)list->elem + list->nb_elem*syntax->list_elem_size;
750         memset(data, 0, syntax->list_elem_size);
751         list->nb_elem++;
752     }
753
754     if (syntax->type != EBML_PASS && syntax->type != EBML_STOP)
755         if ((res = ebml_read_num(matroska, pb, 8, &length)) < 0)
756             return res;
757
758     switch (syntax->type) {
759     case EBML_UINT:  res = ebml_read_uint  (pb, length, data);  break;
760     case EBML_FLOAT: res = ebml_read_float (pb, length, data);  break;
761     case EBML_STR:
762     case EBML_UTF8:  res = ebml_read_ascii (pb, length, data);  break;
763     case EBML_BIN:   res = ebml_read_binary(pb, length, data);  break;
764     case EBML_NEST:  if ((res=ebml_read_master(matroska, length)) < 0)
765                          return res;
766                      if (id == MATROSKA_ID_SEGMENT)
767                          matroska->segment_start = url_ftell(matroska->ctx->pb);
768                      return ebml_parse_nest(matroska, syntax->def.n, data);
769     case EBML_PASS:  return ebml_parse_id(matroska, syntax->def.n, id, data);
770     case EBML_STOP:  *(int *)data = 1;      return 1;
771     default:         return url_fseek(pb,length,SEEK_CUR)<0 ? AVERROR(EIO) : 0;
772     }
773     if (res == AVERROR_INVALIDDATA)
774         av_log(matroska->ctx, AV_LOG_ERROR, "Invalid element\n");
775     else if (res == AVERROR(EIO))
776         av_log(matroska->ctx, AV_LOG_ERROR, "Read error\n");
777     return res;
778 }
779
780 static void ebml_free(EbmlSyntax *syntax, void *data)
781 {
782     int i, j;
783     for (i=0; syntax[i].id; i++) {
784         void *data_off = (char *)data + syntax[i].data_offset;
785         switch (syntax[i].type) {
786         case EBML_STR:
787         case EBML_UTF8:  av_freep(data_off);                      break;
788         case EBML_BIN:   av_freep(&((EbmlBin *)data_off)->data);  break;
789         case EBML_NEST:
790             if (syntax[i].list_elem_size) {
791                 EbmlList *list = data_off;
792                 char *ptr = list->elem;
793                 for (j=0; j<list->nb_elem; j++, ptr+=syntax[i].list_elem_size)
794                     ebml_free(syntax[i].def.n, ptr);
795                 av_free(list->elem);
796             } else
797                 ebml_free(syntax[i].def.n, data_off);
798         default:  break;
799         }
800     }
801 }
802
803
804 /*
805  * Autodetecting...
806  */
807 static int matroska_probe(AVProbeData *p)
808 {
809     uint64_t total = 0;
810     int len_mask = 0x80, size = 1, n = 1;
811     static const char probe_data[] = "matroska";
812
813     /* EBML header? */
814     if (AV_RB32(p->buf) != EBML_ID_HEADER)
815         return 0;
816
817     /* length of header */
818     total = p->buf[4];
819     while (size <= 8 && !(total & len_mask)) {
820         size++;
821         len_mask >>= 1;
822     }
823     if (size > 8)
824       return 0;
825     total &= (len_mask - 1);
826     while (n < size)
827         total = (total << 8) | p->buf[4 + n++];
828
829     /* Does the probe data contain the whole header? */
830     if (p->buf_size < 4 + size + total)
831       return 0;
832
833     /* The header must contain the document type 'matroska'. For now,
834      * we don't parse the whole header but simply check for the
835      * availability of that array of characters inside the header.
836      * Not fully fool-proof, but good enough. */
837     for (n = 4+size; n <= 4+size+total-(sizeof(probe_data)-1); n++)
838         if (!memcmp(p->buf+n, probe_data, sizeof(probe_data)-1))
839             return AVPROBE_SCORE_MAX;
840
841     return 0;
842 }
843
844 static MatroskaTrack *matroska_find_track_by_num(MatroskaDemuxContext *matroska,
845                                                  int num)
846 {
847     MatroskaTrack *tracks = matroska->tracks.elem;
848     int i;
849
850     for (i=0; i < matroska->tracks.nb_elem; i++)
851         if (tracks[i].num == num)
852             return &tracks[i];
853
854     av_log(matroska->ctx, AV_LOG_ERROR, "Invalid track number %d\n", num);
855     return NULL;
856 }
857
858 static int matroska_decode_buffer(uint8_t** buf, int* buf_size,
859                                   MatroskaTrack *track)
860 {
861     MatroskaTrackEncoding *encodings = track->encodings.elem;
862     uint8_t* data = *buf;
863     int isize = *buf_size;
864     uint8_t* pkt_data = NULL;
865     int pkt_size = isize;
866     int result = 0;
867     int olen;
868
869     switch (encodings[0].compression.algo) {
870     case MATROSKA_TRACK_ENCODING_COMP_HEADERSTRIP:
871         return encodings[0].compression.settings.size;
872     case MATROSKA_TRACK_ENCODING_COMP_LZO:
873         do {
874             olen = pkt_size *= 3;
875             pkt_data = av_realloc(pkt_data,
876                                   pkt_size+LZO_OUTPUT_PADDING);
877             result = lzo1x_decode(pkt_data, &olen, data, &isize);
878         } while (result==LZO_OUTPUT_FULL && pkt_size<10000000);
879         if (result)
880             goto failed;
881         pkt_size -= olen;
882         break;
883 #ifdef CONFIG_ZLIB
884     case MATROSKA_TRACK_ENCODING_COMP_ZLIB: {
885         z_stream zstream = {0};
886         if (inflateInit(&zstream) != Z_OK)
887             return -1;
888         zstream.next_in = data;
889         zstream.avail_in = isize;
890         do {
891             pkt_size *= 3;
892             pkt_data = av_realloc(pkt_data, pkt_size);
893             zstream.avail_out = pkt_size - zstream.total_out;
894             zstream.next_out = pkt_data + zstream.total_out;
895             result = inflate(&zstream, Z_NO_FLUSH);
896         } while (result==Z_OK && pkt_size<10000000);
897         pkt_size = zstream.total_out;
898         inflateEnd(&zstream);
899         if (result != Z_STREAM_END)
900             goto failed;
901         break;
902     }
903 #endif
904 #ifdef CONFIG_BZLIB
905     case MATROSKA_TRACK_ENCODING_COMP_BZLIB: {
906         bz_stream bzstream = {0};
907         if (BZ2_bzDecompressInit(&bzstream, 0, 0) != BZ_OK)
908             return -1;
909         bzstream.next_in = data;
910         bzstream.avail_in = isize;
911         do {
912             pkt_size *= 3;
913             pkt_data = av_realloc(pkt_data, pkt_size);
914             bzstream.avail_out = pkt_size - bzstream.total_out_lo32;
915             bzstream.next_out = pkt_data + bzstream.total_out_lo32;
916             result = BZ2_bzDecompress(&bzstream);
917         } while (result==BZ_OK && pkt_size<10000000);
918         pkt_size = bzstream.total_out_lo32;
919         BZ2_bzDecompressEnd(&bzstream);
920         if (result != BZ_STREAM_END)
921             goto failed;
922         break;
923     }
924 #endif
925     default:
926         return -1;
927     }
928
929     *buf = pkt_data;
930     *buf_size = pkt_size;
931     return 0;
932  failed:
933     av_free(pkt_data);
934     return -1;
935 }
936
937 static void matroska_fix_ass_packet(MatroskaDemuxContext *matroska,
938                                     AVPacket *pkt)
939 {
940     char *line, *layer, *ptr = pkt->data, *end = ptr+pkt->size;
941     for (; *ptr!=',' && ptr<end-1; ptr++);
942     if (*ptr == ',')
943         layer = ++ptr;
944     for (; *ptr!=',' && ptr<end-1; ptr++);
945     if (*ptr == ',') {
946         int64_t end_pts = pkt->pts + pkt->convergence_duration;
947         int sc = matroska->time_scale * pkt->pts / 10000000;
948         int ec = matroska->time_scale * end_pts  / 10000000;
949         int sh, sm, ss, eh, em, es, len;
950         sh = sc/360000;  sc -= 360000*sh;
951         sm = sc/  6000;  sc -=   6000*sm;
952         ss = sc/   100;  sc -=    100*ss;
953         eh = ec/360000;  ec -= 360000*eh;
954         em = ec/  6000;  ec -=   6000*em;
955         es = ec/   100;  ec -=    100*es;
956         *ptr++ = '\0';
957         len = 50 + end-ptr + FF_INPUT_BUFFER_PADDING_SIZE;
958         if (!(line = av_malloc(len)))
959             return;
960         snprintf(line,len,"Dialogue: %s,%d:%02d:%02d.%02d,%d:%02d:%02d.%02d,%s",
961                  layer, sh, sm, ss, sc, eh, em, es, ec, ptr);
962         av_free(pkt->data);
963         pkt->data = line;
964         pkt->size = strlen(line);
965     }
966 }
967
968 static void matroska_convert_tags(AVFormatContext *s, EbmlList *list)
969 {
970     MatroskaTag *tags = list->elem;
971     int i, j;
972
973     for (i=0; i < list->nb_elem; i++) {
974         for (j=0; j < ARRAY_SIZE(metadata); j++){
975             if (!strcmp(tags[i].name, metadata[j].name)) {
976                 int *ptr = (int *)((char *)s + metadata[j].offset);
977                 if (*ptr)  continue;
978                 if (metadata[j].size > sizeof(int))
979                     av_strlcpy((char *)ptr, tags[i].string, metadata[j].size);
980                 else
981                     *ptr = atoi(tags[i].string);
982             }
983         }
984         if (tags[i].sub.nb_elem)
985             matroska_convert_tags(s, &tags[i].sub);
986     }
987 }
988
989 static void matroska_execute_seekhead(MatroskaDemuxContext *matroska)
990 {
991     EbmlList *seekhead_list = &matroska->seekhead;
992     MatroskaSeekhead *seekhead = seekhead_list->elem;
993     uint32_t level_up = matroska->level_up;
994     offset_t before_pos = url_ftell(matroska->ctx->pb);
995     MatroskaLevel level;
996     int i;
997
998     for (i=0; i<seekhead_list->nb_elem; i++) {
999         offset_t offset = seekhead[i].pos + matroska->segment_start;
1000
1001         if (seekhead[i].pos <= before_pos
1002             || seekhead[i].id == MATROSKA_ID_SEEKHEAD
1003             || seekhead[i].id == MATROSKA_ID_CLUSTER)
1004             continue;
1005
1006         /* seek */
1007         if (url_fseek(matroska->ctx->pb, offset, SEEK_SET) != offset)
1008             continue;
1009
1010         /* We don't want to lose our seekhead level, so we add
1011          * a dummy. This is a crude hack. */
1012         if (matroska->num_levels == EBML_MAX_DEPTH) {
1013             av_log(matroska->ctx, AV_LOG_INFO,
1014                    "Max EBML element depth (%d) reached, "
1015                    "cannot parse further.\n", EBML_MAX_DEPTH);
1016             break;
1017         }
1018
1019         level.start = 0;
1020         level.length = (uint64_t)-1;
1021         matroska->levels[matroska->num_levels] = level;
1022         matroska->num_levels++;
1023
1024         ebml_parse(matroska, matroska_segment, matroska);
1025
1026         /* remove dummy level */
1027         while (matroska->num_levels) {
1028             uint64_t length = matroska->levels[--matroska->num_levels].length;
1029             if (length == (uint64_t)-1)
1030                 break;
1031         }
1032     }
1033
1034     /* seek back */
1035     url_fseek(matroska->ctx->pb, before_pos, SEEK_SET);
1036     matroska->level_up = level_up;
1037 }
1038
1039 static int matroska_aac_profile(char *codec_id)
1040 {
1041     static const char * const aac_profiles[] = { "MAIN", "LC", "SSR" };
1042     int profile;
1043
1044     for (profile=0; profile<ARRAY_SIZE(aac_profiles); profile++)
1045         if (strstr(codec_id, aac_profiles[profile]))
1046             break;
1047     return profile + 1;
1048 }
1049
1050 static int matroska_aac_sri(int samplerate)
1051 {
1052     int sri;
1053
1054     for (sri=0; sri<ARRAY_SIZE(ff_mpeg4audio_sample_rates); sri++)
1055         if (ff_mpeg4audio_sample_rates[sri] == samplerate)
1056             break;
1057     return sri;
1058 }
1059
1060 static int matroska_read_header(AVFormatContext *s, AVFormatParameters *ap)
1061 {
1062     MatroskaDemuxContext *matroska = s->priv_data;
1063     EbmlList *attachements_list = &matroska->attachments;
1064     MatroskaAttachement *attachements;
1065     EbmlList *chapters_list = &matroska->chapters;
1066     MatroskaChapter *chapters;
1067     MatroskaTrack *tracks;
1068     EbmlList *index_list;
1069     MatroskaIndex *index;
1070     Ebml ebml = { 0 };
1071     AVStream *st;
1072     int i, j;
1073
1074     matroska->ctx = s;
1075
1076     /* First read the EBML header. */
1077     if (ebml_parse(matroska, ebml_syntax, &ebml)
1078         || ebml.version > EBML_VERSION       || ebml.max_size > sizeof(uint64_t)
1079         || ebml.id_length > sizeof(uint32_t) || strcmp(ebml.doctype, "matroska")
1080         || ebml.doctype_version > 2) {
1081         av_log(matroska->ctx, AV_LOG_ERROR,
1082                "EBML header using unsupported features\n"
1083                "(EBML version %"PRIu64", doctype %s, doc version %"PRIu64")\n",
1084                ebml.version, ebml.doctype, ebml.doctype_version);
1085         return AVERROR_NOFMT;
1086     }
1087     ebml_free(ebml_syntax, &ebml);
1088
1089     /* The next thing is a segment. */
1090     if (ebml_parse(matroska, matroska_segments, matroska) < 0)
1091         return -1;
1092     matroska_execute_seekhead(matroska);
1093
1094     if (matroska->duration)
1095         matroska->ctx->duration = matroska->duration * matroska->time_scale
1096                                   * 1000 / AV_TIME_BASE;
1097     if (matroska->title)
1098         strncpy(matroska->ctx->title, matroska->title,
1099                 sizeof(matroska->ctx->title)-1);
1100     matroska_convert_tags(s, &matroska->tags);
1101
1102     tracks = matroska->tracks.elem;
1103     for (i=0; i < matroska->tracks.nb_elem; i++) {
1104         MatroskaTrack *track = &tracks[i];
1105         enum CodecID codec_id = CODEC_ID_NONE;
1106         EbmlList *encodings_list = &tracks->encodings;
1107         MatroskaTrackEncoding *encodings = encodings_list->elem;
1108         uint8_t *extradata = NULL;
1109         int extradata_size = 0;
1110         int extradata_offset = 0;
1111
1112         /* Apply some sanity checks. */
1113         if (track->type != MATROSKA_TRACK_TYPE_VIDEO &&
1114             track->type != MATROSKA_TRACK_TYPE_AUDIO &&
1115             track->type != MATROSKA_TRACK_TYPE_SUBTITLE) {
1116             av_log(matroska->ctx, AV_LOG_INFO,
1117                    "Unknown or unsupported track type %"PRIu64"\n",
1118                    track->type);
1119             continue;
1120         }
1121         if (track->codec_id == NULL)
1122             continue;
1123
1124         if (track->type == MATROSKA_TRACK_TYPE_VIDEO) {
1125             if (!track->default_duration)
1126                 track->default_duration = 1000000000/track->video.frame_rate;
1127             if (!track->video.display_width)
1128                 track->video.display_width = track->video.pixel_width;
1129             if (!track->video.display_height)
1130                 track->video.display_height = track->video.pixel_height;
1131         } else if (track->type == MATROSKA_TRACK_TYPE_AUDIO) {
1132             if (!track->audio.out_samplerate)
1133                 track->audio.out_samplerate = track->audio.samplerate;
1134         }
1135         if (encodings_list->nb_elem > 1) {
1136             av_log(matroska->ctx, AV_LOG_ERROR,
1137                    "Multiple combined encodings no supported");
1138         } else if (encodings_list->nb_elem == 1) {
1139             if (encodings[0].type ||
1140                 (encodings[0].compression.algo != MATROSKA_TRACK_ENCODING_COMP_HEADERSTRIP &&
1141 #ifdef CONFIG_ZLIB
1142                  encodings[0].compression.algo != MATROSKA_TRACK_ENCODING_COMP_ZLIB &&
1143 #endif
1144 #ifdef CONFIG_BZLIB
1145                  encodings[0].compression.algo != MATROSKA_TRACK_ENCODING_COMP_BZLIB &&
1146 #endif
1147                  encodings[0].compression.algo != MATROSKA_TRACK_ENCODING_COMP_LZO)) {
1148                 encodings[0].scope = 0;
1149                 av_log(matroska->ctx, AV_LOG_ERROR,
1150                        "Unsupported encoding type");
1151             } else if (track->codec_priv.size && encodings[0].scope&2) {
1152                 uint8_t *codec_priv = track->codec_priv.data;
1153                 int offset = matroska_decode_buffer(&track->codec_priv.data,
1154                                                     &track->codec_priv.size,
1155                                                     track);
1156                 if (offset < 0) {
1157                     track->codec_priv.data = NULL;
1158                     track->codec_priv.size = 0;
1159                     av_log(matroska->ctx, AV_LOG_ERROR,
1160                            "Failed to decode codec private data\n");
1161                 } else if (offset > 0) {
1162                     track->codec_priv.data = av_malloc(track->codec_priv.size + offset);
1163                     memcpy(track->codec_priv.data,
1164                            encodings[0].compression.settings.data, offset);
1165                     memcpy(track->codec_priv.data+offset, codec_priv,
1166                            track->codec_priv.size);
1167                     track->codec_priv.size += offset;
1168                 }
1169                 if (codec_priv != track->codec_priv.data)
1170                     av_free(codec_priv);
1171             }
1172         }
1173
1174         for(j=0; ff_mkv_codec_tags[j].id != CODEC_ID_NONE; j++){
1175             if(!strncmp(ff_mkv_codec_tags[j].str, track->codec_id,
1176                         strlen(ff_mkv_codec_tags[j].str))){
1177                 codec_id= ff_mkv_codec_tags[j].id;
1178                 break;
1179             }
1180         }
1181
1182         st = track->stream = av_new_stream(s, 0);
1183         if (st == NULL)
1184             return AVERROR(ENOMEM);
1185         track->first_timecode = AV_NOPTS_VALUE;
1186
1187         if (!strcmp(track->codec_id, "V_MS/VFW/FOURCC")
1188             && track->codec_priv.size >= 40
1189             && track->codec_priv.data != NULL) {
1190             track->video.fourcc = AV_RL32(track->codec_priv.data + 16);
1191             codec_id = codec_get_id(codec_bmp_tags, track->video.fourcc);
1192         } else if (!strcmp(track->codec_id, "A_MS/ACM")
1193                    && track->codec_priv.size >= 18
1194                    && track->codec_priv.data != NULL) {
1195             uint16_t tag = AV_RL16(track->codec_priv.data);
1196             codec_id = codec_get_id(codec_wav_tags, tag);
1197         } else if (!strcmp(track->codec_id, "V_QUICKTIME")
1198                    && (track->codec_priv.size >= 86)
1199                    && (track->codec_priv.data != NULL)) {
1200             track->video.fourcc = AV_RL32(track->codec_priv.data);
1201             codec_id=codec_get_id(codec_movvideo_tags, track->video.fourcc);
1202         } else if (codec_id == CODEC_ID_PCM_S16BE) {
1203             switch (track->audio.bitdepth) {
1204             case  8:  codec_id = CODEC_ID_PCM_U8;     break;
1205             case 24:  codec_id = CODEC_ID_PCM_S24BE;  break;
1206             case 32:  codec_id = CODEC_ID_PCM_S32BE;  break;
1207             }
1208         } else if (codec_id == CODEC_ID_PCM_S16LE) {
1209             switch (track->audio.bitdepth) {
1210             case  8:  codec_id = CODEC_ID_PCM_U8;     break;
1211             case 24:  codec_id = CODEC_ID_PCM_S24LE;  break;
1212             case 32:  codec_id = CODEC_ID_PCM_S32LE;  break;
1213             }
1214         } else if (codec_id==CODEC_ID_PCM_F32LE && track->audio.bitdepth==64) {
1215             codec_id = CODEC_ID_PCM_F64LE;
1216         } else if (codec_id == CODEC_ID_AAC && !track->codec_priv.size) {
1217             int profile = matroska_aac_profile(track->codec_id);
1218             int sri = matroska_aac_sri(track->audio.samplerate);
1219             extradata = av_malloc(5);
1220             if (extradata == NULL)
1221                 return AVERROR(ENOMEM);
1222             extradata[0] = (profile << 3) | ((sri&0x0E) >> 1);
1223             extradata[1] = ((sri&0x01) << 7) | (track->audio.channels<<3);
1224             if (strstr(track->codec_id, "SBR")) {
1225                 sri = matroska_aac_sri(track->audio.out_samplerate);
1226                 extradata[2] = 0x56;
1227                 extradata[3] = 0xE5;
1228                 extradata[4] = 0x80 | (sri<<3);
1229                 extradata_size = 5;
1230             } else
1231                 extradata_size = 2;
1232         } else if (codec_id == CODEC_ID_TTA) {
1233             ByteIOContext b;
1234             extradata_size = 30;
1235             extradata = av_mallocz(extradata_size);
1236             if (extradata == NULL)
1237                 return AVERROR(ENOMEM);
1238             init_put_byte(&b, extradata, extradata_size, 1,
1239                           NULL, NULL, NULL, NULL);
1240             put_buffer(&b, "TTA1", 4);
1241             put_le16(&b, 1);
1242             put_le16(&b, track->audio.channels);
1243             put_le16(&b, track->audio.bitdepth);
1244             put_le32(&b, track->audio.out_samplerate);
1245             put_le32(&b, matroska->ctx->duration * track->audio.out_samplerate);
1246         } else if (codec_id == CODEC_ID_RV10 || codec_id == CODEC_ID_RV20 ||
1247                    codec_id == CODEC_ID_RV30 || codec_id == CODEC_ID_RV40) {
1248             extradata_offset = 26;
1249             track->codec_priv.size -= extradata_offset;
1250         } else if (codec_id == CODEC_ID_RA_144) {
1251             track->audio.out_samplerate = 8000;
1252             track->audio.channels = 1;
1253         } else if (codec_id == CODEC_ID_RA_288 || codec_id == CODEC_ID_COOK ||
1254                    codec_id == CODEC_ID_ATRAC3) {
1255             ByteIOContext b;
1256
1257             init_put_byte(&b, track->codec_priv.data,track->codec_priv.size,
1258                           0, NULL, NULL, NULL, NULL);
1259             url_fskip(&b, 24);
1260             track->audio.coded_framesize = get_be32(&b);
1261             url_fskip(&b, 12);
1262             track->audio.sub_packet_h    = get_be16(&b);
1263             track->audio.frame_size      = get_be16(&b);
1264             track->audio.sub_packet_size = get_be16(&b);
1265             track->audio.buf = av_malloc(track->audio.frame_size * track->audio.sub_packet_h);
1266             if (codec_id == CODEC_ID_RA_288) {
1267                 st->codec->block_align = track->audio.coded_framesize;
1268                 track->codec_priv.size = 0;
1269             } else {
1270                 st->codec->block_align = track->audio.sub_packet_size;
1271                 extradata_offset = 78;
1272                 track->codec_priv.size -= extradata_offset;
1273             }
1274         }
1275
1276         if (codec_id == CODEC_ID_NONE)
1277             av_log(matroska->ctx, AV_LOG_INFO,
1278                    "Unknown/unsupported CodecID %s.\n", track->codec_id);
1279
1280         if (track->time_scale < 0.01)
1281             track->time_scale = 1.0;
1282         av_set_pts_info(st, 64, matroska->time_scale*track->time_scale, 1000*1000*1000); /* 64 bit pts in ns */
1283
1284         st->codec->codec_id = codec_id;
1285         st->start_time = 0;
1286         if (strcmp(track->language, "und"))
1287             av_strlcpy(st->language, track->language, 4);
1288
1289         if (track->flag_default)
1290             st->disposition |= AV_DISPOSITION_DEFAULT;
1291
1292         if (track->default_duration)
1293             av_reduce(&st->codec->time_base.num, &st->codec->time_base.den,
1294                       track->default_duration, 1000000000, 30000);
1295
1296         if(extradata){
1297             st->codec->extradata = extradata;
1298             st->codec->extradata_size = extradata_size;
1299         } else if(track->codec_priv.data && track->codec_priv.size > 0){
1300             st->codec->extradata = av_malloc(track->codec_priv.size);
1301             if(st->codec->extradata == NULL)
1302                 return AVERROR(ENOMEM);
1303             st->codec->extradata_size = track->codec_priv.size;
1304             memcpy(st->codec->extradata,
1305                    track->codec_priv.data + extradata_offset,
1306                    track->codec_priv.size);
1307         }
1308
1309         if (track->type == MATROSKA_TRACK_TYPE_VIDEO) {
1310             st->codec->codec_type = CODEC_TYPE_VIDEO;
1311             st->codec->codec_tag  = track->video.fourcc;
1312             st->codec->width  = track->video.pixel_width;
1313             st->codec->height = track->video.pixel_height;
1314             av_reduce(&st->sample_aspect_ratio.num,
1315                       &st->sample_aspect_ratio.den,
1316                       st->codec->height * track->video.display_width,
1317                       st->codec-> width * track->video.display_height,
1318                       255);
1319             st->need_parsing = AVSTREAM_PARSE_HEADERS;
1320         } else if (track->type == MATROSKA_TRACK_TYPE_AUDIO) {
1321             st->codec->codec_type = CODEC_TYPE_AUDIO;
1322             st->codec->sample_rate = track->audio.out_samplerate;
1323             st->codec->channels = track->audio.channels;
1324         } else if (track->type == MATROSKA_TRACK_TYPE_SUBTITLE) {
1325             st->codec->codec_type = CODEC_TYPE_SUBTITLE;
1326         }
1327     }
1328
1329     attachements = attachements_list->elem;
1330     for (j=0; j<attachements_list->nb_elem; j++) {
1331         if (!(attachements[j].filename && attachements[j].mime &&
1332               attachements[j].bin.data && attachements[j].bin.size > 0)) {
1333             av_log(matroska->ctx, AV_LOG_ERROR, "incomplete attachment\n");
1334         } else {
1335             AVStream *st = av_new_stream(s, 0);
1336             if (st == NULL)
1337                 break;
1338             st->filename          = av_strdup(attachements[j].filename);
1339             st->codec->codec_id = CODEC_ID_NONE;
1340             st->codec->codec_type = CODEC_TYPE_ATTACHMENT;
1341             st->codec->extradata  = av_malloc(attachements[j].bin.size);
1342             if(st->codec->extradata == NULL)
1343                 break;
1344             st->codec->extradata_size = attachements[j].bin.size;
1345             memcpy(st->codec->extradata, attachements[j].bin.data, attachements[j].bin.size);
1346
1347             for (i=0; ff_mkv_mime_tags[i].id != CODEC_ID_NONE; i++) {
1348                 if (!strncmp(ff_mkv_mime_tags[i].str, attachements[j].mime,
1349                              strlen(ff_mkv_mime_tags[i].str))) {
1350                     st->codec->codec_id = ff_mkv_mime_tags[i].id;
1351                     break;
1352                 }
1353             }
1354         }
1355     }
1356
1357     chapters = chapters_list->elem;
1358     for (i=0; i<chapters_list->nb_elem; i++)
1359         if (chapters[i].start != AV_NOPTS_VALUE && chapters[i].uid)
1360             ff_new_chapter(s, chapters[i].uid, (AVRational){1, 1000000000},
1361                            chapters[i].start, chapters[i].end,
1362                            chapters[i].title);
1363
1364     index_list = &matroska->index;
1365     index = index_list->elem;
1366     for (i=0; i<index_list->nb_elem; i++) {
1367         EbmlList *pos_list = &index[i].pos;
1368         MatroskaIndexPos *pos = pos_list->elem;
1369         for (j=0; j<pos_list->nb_elem; j++) {
1370             MatroskaTrack *track = matroska_find_track_by_num(matroska,
1371                                                               pos[j].track);
1372             if (track && track->stream)
1373                 av_add_index_entry(track->stream,
1374                                    pos[j].pos + matroska->segment_start,
1375                                    index[i].time, 0, 0, AVINDEX_KEYFRAME);
1376         }
1377     }
1378
1379     return 0;
1380 }
1381
1382 /*
1383  * Put one packet in an application-supplied AVPacket struct.
1384  * Returns 0 on success or -1 on failure.
1385  */
1386 static int matroska_deliver_packet(MatroskaDemuxContext *matroska,
1387                                    AVPacket *pkt)
1388 {
1389     if (matroska->num_packets > 0) {
1390         memcpy(pkt, matroska->packets[0], sizeof(AVPacket));
1391         av_free(matroska->packets[0]);
1392         if (matroska->num_packets > 1) {
1393             memmove(&matroska->packets[0], &matroska->packets[1],
1394                     (matroska->num_packets - 1) * sizeof(AVPacket *));
1395             matroska->packets =
1396                 av_realloc(matroska->packets, (matroska->num_packets - 1) *
1397                            sizeof(AVPacket *));
1398         } else {
1399             av_freep(&matroska->packets);
1400         }
1401         matroska->num_packets--;
1402         return 0;
1403     }
1404
1405     return -1;
1406 }
1407
1408 /*
1409  * Free all packets in our internal queue.
1410  */
1411 static void matroska_clear_queue(MatroskaDemuxContext *matroska)
1412 {
1413     if (matroska->packets) {
1414         int n;
1415         for (n = 0; n < matroska->num_packets; n++) {
1416             av_free_packet(matroska->packets[n]);
1417             av_free(matroska->packets[n]);
1418         }
1419         av_freep(&matroska->packets);
1420         matroska->num_packets = 0;
1421     }
1422 }
1423
1424 static int matroska_parse_block(MatroskaDemuxContext *matroska, uint8_t *data,
1425                                 int size, int64_t pos, uint64_t cluster_time,
1426                                 uint64_t duration, int is_keyframe,
1427                                 int64_t cluster_pos)
1428 {
1429     uint64_t timecode = AV_NOPTS_VALUE;
1430     MatroskaTrack *track;
1431     int res = 0;
1432     AVStream *st;
1433     AVPacket *pkt;
1434     int16_t block_time;
1435     uint32_t *lace_size = NULL;
1436     int n, flags, laces = 0;
1437     uint64_t num;
1438
1439     if ((n = matroska_ebmlnum_uint(matroska, data, size, &num)) < 0) {
1440         av_log(matroska->ctx, AV_LOG_ERROR, "EBML block data error\n");
1441         return res;
1442     }
1443     data += n;
1444     size -= n;
1445
1446     track = matroska_find_track_by_num(matroska, num);
1447     if (size <= 3 || !track || !track->stream) {
1448         av_log(matroska->ctx, AV_LOG_INFO,
1449                "Invalid stream %"PRIu64" or size %u\n", num, size);
1450         return res;
1451     }
1452     st = track->stream;
1453     if (st->discard >= AVDISCARD_ALL)
1454         return res;
1455     if (duration == AV_NOPTS_VALUE)
1456         duration = track->default_duration / matroska->time_scale;
1457
1458     block_time = AV_RB16(data);
1459     data += 2;
1460     flags = *data++;
1461     size -= 3;
1462     if (is_keyframe == -1)
1463         is_keyframe = flags & 0x80 ? PKT_FLAG_KEY : 0;
1464
1465     if (cluster_time != (uint64_t)-1
1466         && (block_time >= 0 || cluster_time >= -block_time)) {
1467         timecode = cluster_time + block_time;
1468         if (track->type == MATROSKA_TRACK_TYPE_SUBTITLE
1469             && timecode < track->end_timecode)
1470             is_keyframe = 0;  /* overlapping subtitles are not key frame */
1471         if (is_keyframe) {
1472             av_add_index_entry(st, cluster_pos, timecode, 0,0,AVINDEX_KEYFRAME);
1473             if (track->first_timecode == AV_NOPTS_VALUE)
1474                 track->first_timecode = timecode;
1475         }
1476         track->end_timecode = FFMAX(track->end_timecode, timecode+duration);
1477     }
1478
1479     if (matroska->skip_to_keyframe && track->type != MATROSKA_TRACK_TYPE_SUBTITLE) {
1480         if (!is_keyframe || timecode < matroska->skip_to_timecode)
1481             return res;
1482         matroska->skip_to_keyframe = 0;
1483     }
1484
1485     switch ((flags & 0x06) >> 1) {
1486         case 0x0: /* no lacing */
1487             laces = 1;
1488             lace_size = av_mallocz(sizeof(int));
1489             lace_size[0] = size;
1490             break;
1491
1492         case 0x1: /* Xiph lacing */
1493         case 0x2: /* fixed-size lacing */
1494         case 0x3: /* EBML lacing */
1495             assert(size>0); // size <=3 is checked before size-=3 above
1496             laces = (*data) + 1;
1497             data += 1;
1498             size -= 1;
1499             lace_size = av_mallocz(laces * sizeof(int));
1500
1501             switch ((flags & 0x06) >> 1) {
1502                 case 0x1: /* Xiph lacing */ {
1503                     uint8_t temp;
1504                     uint32_t total = 0;
1505                     for (n = 0; res == 0 && n < laces - 1; n++) {
1506                         while (1) {
1507                             if (size == 0) {
1508                                 res = -1;
1509                                 break;
1510                             }
1511                             temp = *data;
1512                             lace_size[n] += temp;
1513                             data += 1;
1514                             size -= 1;
1515                             if (temp != 0xff)
1516                                 break;
1517                         }
1518                         total += lace_size[n];
1519                     }
1520                     lace_size[n] = size - total;
1521                     break;
1522                 }
1523
1524                 case 0x2: /* fixed-size lacing */
1525                     for (n = 0; n < laces; n++)
1526                         lace_size[n] = size / laces;
1527                     break;
1528
1529                 case 0x3: /* EBML lacing */ {
1530                     uint32_t total;
1531                     n = matroska_ebmlnum_uint(matroska, data, size, &num);
1532                     if (n < 0) {
1533                         av_log(matroska->ctx, AV_LOG_INFO,
1534                                "EBML block data error\n");
1535                         break;
1536                     }
1537                     data += n;
1538                     size -= n;
1539                     total = lace_size[0] = num;
1540                     for (n = 1; res == 0 && n < laces - 1; n++) {
1541                         int64_t snum;
1542                         int r;
1543                         r = matroska_ebmlnum_sint(matroska, data, size, &snum);
1544                         if (r < 0) {
1545                             av_log(matroska->ctx, AV_LOG_INFO,
1546                                    "EBML block data error\n");
1547                             break;
1548                         }
1549                         data += r;
1550                         size -= r;
1551                         lace_size[n] = lace_size[n - 1] + snum;
1552                         total += lace_size[n];
1553                     }
1554                     lace_size[n] = size - total;
1555                     break;
1556                 }
1557             }
1558             break;
1559     }
1560
1561     if (res == 0) {
1562         for (n = 0; n < laces; n++) {
1563             if (st->codec->codec_id == CODEC_ID_RA_288 ||
1564                 st->codec->codec_id == CODEC_ID_COOK ||
1565                 st->codec->codec_id == CODEC_ID_ATRAC3) {
1566                 int a = st->codec->block_align;
1567                 int sps = track->audio.sub_packet_size;
1568                 int cfs = track->audio.coded_framesize;
1569                 int h = track->audio.sub_packet_h;
1570                 int y = track->audio.sub_packet_cnt;
1571                 int w = track->audio.frame_size;
1572                 int x;
1573
1574                 if (!track->audio.pkt_cnt) {
1575                     if (st->codec->codec_id == CODEC_ID_RA_288)
1576                         for (x=0; x<h/2; x++)
1577                             memcpy(track->audio.buf+x*2*w+y*cfs,
1578                                    data+x*cfs, cfs);
1579                     else
1580                         for (x=0; x<w/sps; x++)
1581                             memcpy(track->audio.buf+sps*(h*x+((h+1)/2)*(y&1)+(y>>1)), data+x*sps, sps);
1582
1583                     if (++track->audio.sub_packet_cnt >= h) {
1584                         track->audio.sub_packet_cnt = 0;
1585                         track->audio.pkt_cnt = h*w / a;
1586                     }
1587                 }
1588                 while (track->audio.pkt_cnt) {
1589                     pkt = av_mallocz(sizeof(AVPacket));
1590                     av_new_packet(pkt, a);
1591                     memcpy(pkt->data, track->audio.buf
1592                            + a * (h*w / a - track->audio.pkt_cnt--), a);
1593                     pkt->pos = pos;
1594                     pkt->stream_index = st->index;
1595                     dynarray_add(&matroska->packets,&matroska->num_packets,pkt);
1596                 }
1597             } else {
1598                 MatroskaTrackEncoding *encodings = track->encodings.elem;
1599                 int offset = 0, pkt_size = lace_size[n];
1600                 uint8_t *pkt_data = data;
1601
1602                 if (encodings && encodings->scope & 1) {
1603                     offset = matroska_decode_buffer(&pkt_data,&pkt_size, track);
1604                     if (offset < 0)
1605                         continue;
1606                 }
1607
1608                 pkt = av_mallocz(sizeof(AVPacket));
1609                 /* XXX: prevent data copy... */
1610                 if (av_new_packet(pkt, pkt_size+offset) < 0) {
1611                     av_free(pkt);
1612                     res = AVERROR(ENOMEM);
1613                     n = laces-1;
1614                     break;
1615                 }
1616                 if (offset)
1617                     memcpy (pkt->data, encodings->compression.settings.data, offset);
1618                 memcpy (pkt->data+offset, pkt_data, pkt_size);
1619
1620                 if (pkt_data != data)
1621                     av_free(pkt_data);
1622
1623                 if (n == 0)
1624                     pkt->flags = is_keyframe;
1625                 pkt->stream_index = st->index;
1626
1627                 pkt->pts = timecode;
1628                 pkt->pos = pos;
1629                 if (track->type == MATROSKA_TRACK_TYPE_SUBTITLE)
1630                     pkt->convergence_duration = duration;
1631                 else
1632                     pkt->duration = duration;
1633
1634                 if (st->codec->codec_id == CODEC_ID_SSA)
1635                     matroska_fix_ass_packet(matroska, pkt);
1636
1637                 dynarray_add(&matroska->packets, &matroska->num_packets, pkt);
1638             }
1639
1640             if (timecode != AV_NOPTS_VALUE)
1641                 timecode = duration ? timecode + duration : AV_NOPTS_VALUE;
1642             data += lace_size[n];
1643         }
1644     }
1645
1646     av_free(lace_size);
1647     return res;
1648 }
1649
1650 static int matroska_parse_cluster(MatroskaDemuxContext *matroska)
1651 {
1652     MatroskaCluster cluster = { 0 };
1653     EbmlList *blocks_list;
1654     MatroskaBlock *blocks;
1655     int i, res;
1656     offset_t pos = url_ftell(matroska->ctx->pb);
1657     if (matroska->has_cluster_id){
1658         /* For the first cluster we parse, its ID was already read as
1659            part of matroska_read_header(), so don't read it again */
1660         res = ebml_parse_id(matroska, matroska_clusters,
1661                             MATROSKA_ID_CLUSTER, &cluster);
1662         pos -= 4;  /* sizeof the ID which was already read */
1663         matroska->has_cluster_id = 0;
1664     } else
1665         res = ebml_parse(matroska, matroska_clusters, &cluster);
1666     blocks_list = &cluster.blocks;
1667     blocks = blocks_list->elem;
1668     for (i=0; i<blocks_list->nb_elem; i++)
1669         if (blocks[i].bin.size > 0)
1670             res=matroska_parse_block(matroska,
1671                                      blocks[i].bin.data, blocks[i].bin.size,
1672                                      blocks[i].bin.pos,  cluster.timecode,
1673                                      blocks[i].duration, !blocks[i].reference,
1674                                      pos);
1675     ebml_free(matroska_cluster, &cluster);
1676     if (res < 0)  matroska->done = 1;
1677     return res;
1678 }
1679
1680 static int matroska_read_packet(AVFormatContext *s, AVPacket *pkt)
1681 {
1682     MatroskaDemuxContext *matroska = s->priv_data;
1683
1684     while (matroska_deliver_packet(matroska, pkt)) {
1685         if (matroska->done)
1686             return AVERROR(EIO);
1687         matroska_parse_cluster(matroska);
1688     }
1689
1690     return 0;
1691 }
1692
1693 static int matroska_read_seek(AVFormatContext *s, int stream_index,
1694                               int64_t timestamp, int flags)
1695 {
1696     MatroskaDemuxContext *matroska = s->priv_data;
1697     MatroskaTrack *tracks = matroska->tracks.elem;
1698     AVStream *st = s->streams[stream_index];
1699     int i, index, index_sub, index_min;
1700     int64_t first_timecode = 0;
1701
1702     for (i=0; i < matroska->tracks.nb_elem; i++)
1703         if (tracks[i].stream->index == stream_index &&
1704             tracks[i].first_timecode != AV_NOPTS_VALUE)
1705             first_timecode = tracks[i].first_timecode;
1706
1707     if (timestamp < first_timecode)
1708         timestamp = first_timecode;
1709
1710     if ((index = av_index_search_timestamp(st, timestamp, flags)) < 0) {
1711         if (st->nb_index_entries)
1712             url_fseek(s->pb, st->index_entries[st->nb_index_entries-1].pos, SEEK_SET);
1713         while ((index = av_index_search_timestamp(st, timestamp, flags)) < 0) {
1714             matroska_clear_queue(matroska);
1715             if (matroska_parse_cluster(matroska) < 0)
1716                 break;
1717         }
1718     }
1719
1720     matroska_clear_queue(matroska);
1721     if (index < 0)
1722         return 0;
1723
1724     index_min = index;
1725     for (i=0; i < matroska->tracks.nb_elem; i++) {
1726         tracks[i].end_timecode = 0;
1727         if (tracks[i].type == MATROSKA_TRACK_TYPE_SUBTITLE
1728             && !tracks[i].stream->discard != AVDISCARD_ALL) {
1729             index_sub = av_index_search_timestamp(tracks[i].stream, st->index_entries[index].timestamp, AVSEEK_FLAG_BACKWARD);
1730             if (index_sub >= 0
1731                 && st->index_entries[index_sub].pos < st->index_entries[index_min].pos
1732                 && st->index_entries[index].timestamp - st->index_entries[index_sub].timestamp < 30000000000/matroska->time_scale)
1733                 index_min = index_sub;
1734         }
1735     }
1736
1737     url_fseek(s->pb, st->index_entries[index_min].pos, SEEK_SET);
1738     matroska->skip_to_keyframe = !(flags & AVSEEK_FLAG_ANY);
1739     matroska->skip_to_timecode = st->index_entries[index].timestamp;
1740     matroska->done = 0;
1741     av_update_cur_dts(s, st, st->index_entries[index].timestamp);
1742     return 0;
1743 }
1744
1745 static int matroska_read_close(AVFormatContext *s)
1746 {
1747     MatroskaDemuxContext *matroska = s->priv_data;
1748     MatroskaTrack *tracks = matroska->tracks.elem;
1749     int n;
1750
1751     matroska_clear_queue(matroska);
1752
1753     for (n=0; n < matroska->tracks.nb_elem; n++)
1754         if (tracks[n].type == MATROSKA_TRACK_TYPE_AUDIO)
1755             av_free(tracks[n].audio.buf);
1756     ebml_free(matroska_segment, matroska);
1757
1758     return 0;
1759 }
1760
1761 AVInputFormat matroska_demuxer = {
1762     "matroska",
1763     NULL_IF_CONFIG_SMALL("Matroska file format"),
1764     sizeof(MatroskaDemuxContext),
1765     matroska_probe,
1766     matroska_read_header,
1767     matroska_read_packet,
1768     matroska_read_close,
1769     matroska_read_seek,
1770 };