Merge commit '36ef5369ee9b336febc2c270f8718cec4476cb85'
[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
24  * Matroska file demuxer
25  * @author Ronald Bultje <rbultje@ronald.bitfreak.net>
26  * @author with a little help from Moritz Bunkus <moritz@bunkus.org>
27  * @author totally reworked by Aurelien Jacobs <aurel@gnuage.org>
28  * @see specs available on the Matroska project page: http://www.matroska.org/
29  */
30
31 #include <stdio.h>
32 #include "avformat.h"
33 #include "internal.h"
34 #include "avio_internal.h"
35 /* For ff_codec_get_id(). */
36 #include "riff.h"
37 #include "isom.h"
38 #include "rm.h"
39 #include "matroska.h"
40 #include "libavcodec/mpeg4audio.h"
41 #include "libavutil/intfloat.h"
42 #include "libavutil/intreadwrite.h"
43 #include "libavutil/avstring.h"
44 #include "libavutil/lzo.h"
45 #include "libavutil/dict.h"
46 #if CONFIG_ZLIB
47 #include <zlib.h>
48 #endif
49 #if CONFIG_BZLIB
50 #include <bzlib.h>
51 #endif
52
53 typedef enum {
54     EBML_NONE,
55     EBML_UINT,
56     EBML_FLOAT,
57     EBML_STR,
58     EBML_UTF8,
59     EBML_BIN,
60     EBML_NEST,
61     EBML_PASS,
62     EBML_STOP,
63     EBML_TYPE_COUNT
64 } EbmlType;
65
66 typedef const struct EbmlSyntax {
67     uint32_t id;
68     EbmlType type;
69     int list_elem_size;
70     int data_offset;
71     union {
72         uint64_t    u;
73         double      f;
74         const char *s;
75         const struct EbmlSyntax *n;
76     } def;
77 } EbmlSyntax;
78
79 typedef struct {
80     int nb_elem;
81     void *elem;
82 } EbmlList;
83
84 typedef struct {
85     int      size;
86     uint8_t *data;
87     int64_t  pos;
88 } EbmlBin;
89
90 typedef struct {
91     uint64_t version;
92     uint64_t max_size;
93     uint64_t id_length;
94     char    *doctype;
95     uint64_t doctype_version;
96 } Ebml;
97
98 typedef struct {
99     uint64_t algo;
100     EbmlBin  settings;
101 } MatroskaTrackCompression;
102
103 typedef struct {
104     uint64_t scope;
105     uint64_t type;
106     MatroskaTrackCompression compression;
107 } MatroskaTrackEncoding;
108
109 typedef struct {
110     double   frame_rate;
111     uint64_t display_width;
112     uint64_t display_height;
113     uint64_t pixel_width;
114     uint64_t pixel_height;
115     EbmlBin color_space;
116     uint64_t stereo_mode;
117 } MatroskaTrackVideo;
118
119 typedef struct {
120     double   samplerate;
121     double   out_samplerate;
122     uint64_t bitdepth;
123     uint64_t channels;
124
125     /* real audio header (extracted from extradata) */
126     int      coded_framesize;
127     int      sub_packet_h;
128     int      frame_size;
129     int      sub_packet_size;
130     int      sub_packet_cnt;
131     int      pkt_cnt;
132     uint64_t buf_timecode;
133     uint8_t *buf;
134 } MatroskaTrackAudio;
135
136 typedef struct {
137     uint64_t uid;
138     uint64_t type;
139 } MatroskaTrackPlane;
140
141 typedef struct {
142     EbmlList combine_planes;
143 } MatroskaTrackOperation;
144
145 typedef struct {
146     uint64_t num;
147     uint64_t uid;
148     uint64_t type;
149     char    *name;
150     char    *codec_id;
151     EbmlBin  codec_priv;
152     char    *language;
153     double time_scale;
154     uint64_t default_duration;
155     uint64_t flag_default;
156     uint64_t flag_forced;
157     MatroskaTrackVideo video;
158     MatroskaTrackAudio audio;
159     MatroskaTrackOperation operation;
160     EbmlList encodings;
161
162     AVStream *stream;
163     int64_t end_timecode;
164     int ms_compat;
165 } MatroskaTrack;
166
167 typedef struct {
168     uint64_t uid;
169     char *filename;
170     char *mime;
171     EbmlBin bin;
172
173     AVStream *stream;
174 } MatroskaAttachement;
175
176 typedef struct {
177     uint64_t start;
178     uint64_t end;
179     uint64_t uid;
180     char    *title;
181
182     AVChapter *chapter;
183 } MatroskaChapter;
184
185 typedef struct {
186     uint64_t track;
187     uint64_t pos;
188 } MatroskaIndexPos;
189
190 typedef struct {
191     uint64_t time;
192     EbmlList pos;
193 } MatroskaIndex;
194
195 typedef struct {
196     char *name;
197     char *string;
198     char *lang;
199     uint64_t def;
200     EbmlList sub;
201 } MatroskaTag;
202
203 typedef struct {
204     char    *type;
205     uint64_t typevalue;
206     uint64_t trackuid;
207     uint64_t chapteruid;
208     uint64_t attachuid;
209 } MatroskaTagTarget;
210
211 typedef struct {
212     MatroskaTagTarget target;
213     EbmlList tag;
214 } MatroskaTags;
215
216 typedef struct {
217     uint64_t id;
218     uint64_t pos;
219 } MatroskaSeekhead;
220
221 typedef struct {
222     uint64_t start;
223     uint64_t length;
224 } MatroskaLevel;
225
226 typedef struct {
227     uint64_t timecode;
228     EbmlList blocks;
229 } MatroskaCluster;
230
231 typedef struct {
232     AVFormatContext *ctx;
233
234     /* EBML stuff */
235     int num_levels;
236     MatroskaLevel levels[EBML_MAX_DEPTH];
237     int level_up;
238     uint32_t current_id;
239
240     uint64_t time_scale;
241     double   duration;
242     char    *title;
243     EbmlBin date_utc;
244     EbmlList tracks;
245     EbmlList attachments;
246     EbmlList chapters;
247     EbmlList index;
248     EbmlList tags;
249     EbmlList seekhead;
250
251     /* byte position of the segment inside the stream */
252     int64_t segment_start;
253
254     /* the packet queue */
255     AVPacket **packets;
256     int num_packets;
257     AVPacket *prev_pkt;
258
259     int done;
260
261     /* What to skip before effectively reading a packet. */
262     int skip_to_keyframe;
263     uint64_t skip_to_timecode;
264
265     /* File has a CUES element, but we defer parsing until it is needed. */
266     int cues_parsing_deferred;
267
268     int current_cluster_num_blocks;
269     int64_t current_cluster_pos;
270     MatroskaCluster current_cluster;
271
272     /* File has SSA subtitles which prevent incremental cluster parsing. */
273     int contains_ssa;
274 } MatroskaDemuxContext;
275
276 typedef struct {
277     uint64_t duration;
278     int64_t  reference;
279     uint64_t non_simple;
280     EbmlBin  bin;
281 } MatroskaBlock;
282
283 static EbmlSyntax ebml_header[] = {
284     { EBML_ID_EBMLREADVERSION,        EBML_UINT, 0, offsetof(Ebml,version), {.u=EBML_VERSION} },
285     { EBML_ID_EBMLMAXSIZELENGTH,      EBML_UINT, 0, offsetof(Ebml,max_size), {.u=8} },
286     { EBML_ID_EBMLMAXIDLENGTH,        EBML_UINT, 0, offsetof(Ebml,id_length), {.u=4} },
287     { EBML_ID_DOCTYPE,                EBML_STR,  0, offsetof(Ebml,doctype), {.s="(none)"} },
288     { EBML_ID_DOCTYPEREADVERSION,     EBML_UINT, 0, offsetof(Ebml,doctype_version), {.u=1} },
289     { EBML_ID_EBMLVERSION,            EBML_NONE },
290     { EBML_ID_DOCTYPEVERSION,         EBML_NONE },
291     { 0 }
292 };
293
294 static EbmlSyntax ebml_syntax[] = {
295     { EBML_ID_HEADER,                 EBML_NEST, 0, 0, {.n=ebml_header} },
296     { 0 }
297 };
298
299 static EbmlSyntax matroska_info[] = {
300     { MATROSKA_ID_TIMECODESCALE,      EBML_UINT,  0, offsetof(MatroskaDemuxContext,time_scale), {.u=1000000} },
301     { MATROSKA_ID_DURATION,           EBML_FLOAT, 0, offsetof(MatroskaDemuxContext,duration) },
302     { MATROSKA_ID_TITLE,              EBML_UTF8,  0, offsetof(MatroskaDemuxContext,title) },
303     { MATROSKA_ID_WRITINGAPP,         EBML_NONE },
304     { MATROSKA_ID_MUXINGAPP,          EBML_NONE },
305     { MATROSKA_ID_DATEUTC,            EBML_BIN,  0, offsetof(MatroskaDemuxContext,date_utc) },
306     { MATROSKA_ID_SEGMENTUID,         EBML_NONE },
307     { 0 }
308 };
309
310 static EbmlSyntax matroska_track_video[] = {
311     { MATROSKA_ID_VIDEOFRAMERATE,     EBML_FLOAT,0, offsetof(MatroskaTrackVideo,frame_rate) },
312     { MATROSKA_ID_VIDEODISPLAYWIDTH,  EBML_UINT, 0, offsetof(MatroskaTrackVideo,display_width) },
313     { MATROSKA_ID_VIDEODISPLAYHEIGHT, EBML_UINT, 0, offsetof(MatroskaTrackVideo,display_height) },
314     { MATROSKA_ID_VIDEOPIXELWIDTH,    EBML_UINT, 0, offsetof(MatroskaTrackVideo,pixel_width) },
315     { MATROSKA_ID_VIDEOPIXELHEIGHT,   EBML_UINT, 0, offsetof(MatroskaTrackVideo,pixel_height) },
316     { MATROSKA_ID_VIDEOCOLORSPACE,    EBML_BIN,  0, offsetof(MatroskaTrackVideo,color_space) },
317     { MATROSKA_ID_VIDEOSTEREOMODE,    EBML_UINT, 0, offsetof(MatroskaTrackVideo,stereo_mode) },
318     { MATROSKA_ID_VIDEOPIXELCROPB,    EBML_NONE },
319     { MATROSKA_ID_VIDEOPIXELCROPT,    EBML_NONE },
320     { MATROSKA_ID_VIDEOPIXELCROPL,    EBML_NONE },
321     { MATROSKA_ID_VIDEOPIXELCROPR,    EBML_NONE },
322     { MATROSKA_ID_VIDEODISPLAYUNIT,   EBML_NONE },
323     { MATROSKA_ID_VIDEOFLAGINTERLACED,EBML_NONE },
324     { MATROSKA_ID_VIDEOASPECTRATIO,   EBML_NONE },
325     { 0 }
326 };
327
328 static EbmlSyntax matroska_track_audio[] = {
329     { MATROSKA_ID_AUDIOSAMPLINGFREQ,  EBML_FLOAT,0, offsetof(MatroskaTrackAudio,samplerate), {.f=8000.0} },
330     { MATROSKA_ID_AUDIOOUTSAMPLINGFREQ,EBML_FLOAT,0,offsetof(MatroskaTrackAudio,out_samplerate) },
331     { MATROSKA_ID_AUDIOBITDEPTH,      EBML_UINT, 0, offsetof(MatroskaTrackAudio,bitdepth) },
332     { MATROSKA_ID_AUDIOCHANNELS,      EBML_UINT, 0, offsetof(MatroskaTrackAudio,channels), {.u=1} },
333     { 0 }
334 };
335
336 static EbmlSyntax matroska_track_encoding_compression[] = {
337     { MATROSKA_ID_ENCODINGCOMPALGO,   EBML_UINT, 0, offsetof(MatroskaTrackCompression,algo), {.u=0} },
338     { MATROSKA_ID_ENCODINGCOMPSETTINGS,EBML_BIN, 0, offsetof(MatroskaTrackCompression,settings) },
339     { 0 }
340 };
341
342 static EbmlSyntax matroska_track_encoding[] = {
343     { MATROSKA_ID_ENCODINGSCOPE,      EBML_UINT, 0, offsetof(MatroskaTrackEncoding,scope), {.u=1} },
344     { MATROSKA_ID_ENCODINGTYPE,       EBML_UINT, 0, offsetof(MatroskaTrackEncoding,type), {.u=0} },
345     { MATROSKA_ID_ENCODINGCOMPRESSION,EBML_NEST, 0, offsetof(MatroskaTrackEncoding,compression), {.n=matroska_track_encoding_compression} },
346     { MATROSKA_ID_ENCODINGORDER,      EBML_NONE },
347     { 0 }
348 };
349
350 static EbmlSyntax matroska_track_encodings[] = {
351     { MATROSKA_ID_TRACKCONTENTENCODING, EBML_NEST, sizeof(MatroskaTrackEncoding), offsetof(MatroskaTrack,encodings), {.n=matroska_track_encoding} },
352     { 0 }
353 };
354
355 static EbmlSyntax matroska_track_plane[] = {
356     { MATROSKA_ID_TRACKPLANEUID,  EBML_UINT, 0, offsetof(MatroskaTrackPlane,uid) },
357     { MATROSKA_ID_TRACKPLANETYPE, EBML_UINT, 0, offsetof(MatroskaTrackPlane,type) },
358     { 0 }
359 };
360
361 static EbmlSyntax matroska_track_combine_planes[] = {
362     { MATROSKA_ID_TRACKPLANE, EBML_NEST, sizeof(MatroskaTrackPlane), offsetof(MatroskaTrackOperation,combine_planes), {.n=matroska_track_plane} },
363     { 0 }
364 };
365
366 static EbmlSyntax matroska_track_operation[] = {
367     { MATROSKA_ID_TRACKCOMBINEPLANES, EBML_NEST, 0, 0, {.n=matroska_track_combine_planes} },
368     { 0 }
369 };
370
371 static EbmlSyntax matroska_track[] = {
372     { MATROSKA_ID_TRACKNUMBER,          EBML_UINT, 0, offsetof(MatroskaTrack,num) },
373     { MATROSKA_ID_TRACKNAME,            EBML_UTF8, 0, offsetof(MatroskaTrack,name) },
374     { MATROSKA_ID_TRACKUID,             EBML_UINT, 0, offsetof(MatroskaTrack,uid) },
375     { MATROSKA_ID_TRACKTYPE,            EBML_UINT, 0, offsetof(MatroskaTrack,type) },
376     { MATROSKA_ID_CODECID,              EBML_STR,  0, offsetof(MatroskaTrack,codec_id) },
377     { MATROSKA_ID_CODECPRIVATE,         EBML_BIN,  0, offsetof(MatroskaTrack,codec_priv) },
378     { MATROSKA_ID_TRACKLANGUAGE,        EBML_UTF8, 0, offsetof(MatroskaTrack,language), {.s="eng"} },
379     { MATROSKA_ID_TRACKDEFAULTDURATION, EBML_UINT, 0, offsetof(MatroskaTrack,default_duration) },
380     { MATROSKA_ID_TRACKTIMECODESCALE,   EBML_FLOAT,0, offsetof(MatroskaTrack,time_scale), {.f=1.0} },
381     { MATROSKA_ID_TRACKFLAGDEFAULT,     EBML_UINT, 0, offsetof(MatroskaTrack,flag_default), {.u=1} },
382     { MATROSKA_ID_TRACKFLAGFORCED,      EBML_UINT, 0, offsetof(MatroskaTrack,flag_forced), {.u=0} },
383     { MATROSKA_ID_TRACKVIDEO,           EBML_NEST, 0, offsetof(MatroskaTrack,video), {.n=matroska_track_video} },
384     { MATROSKA_ID_TRACKAUDIO,           EBML_NEST, 0, offsetof(MatroskaTrack,audio), {.n=matroska_track_audio} },
385     { MATROSKA_ID_TRACKOPERATION,       EBML_NEST, 0, offsetof(MatroskaTrack,operation), {.n=matroska_track_operation} },
386     { MATROSKA_ID_TRACKCONTENTENCODINGS,EBML_NEST, 0, 0, {.n=matroska_track_encodings} },
387     { MATROSKA_ID_TRACKFLAGENABLED,     EBML_NONE },
388     { MATROSKA_ID_TRACKFLAGLACING,      EBML_NONE },
389     { MATROSKA_ID_CODECNAME,            EBML_NONE },
390     { MATROSKA_ID_CODECDECODEALL,       EBML_NONE },
391     { MATROSKA_ID_CODECINFOURL,         EBML_NONE },
392     { MATROSKA_ID_CODECDOWNLOADURL,     EBML_NONE },
393     { MATROSKA_ID_TRACKMINCACHE,        EBML_NONE },
394     { MATROSKA_ID_TRACKMAXCACHE,        EBML_NONE },
395     { MATROSKA_ID_TRACKMAXBLKADDID,     EBML_NONE },
396     { 0 }
397 };
398
399 static EbmlSyntax matroska_tracks[] = {
400     { MATROSKA_ID_TRACKENTRY,         EBML_NEST, sizeof(MatroskaTrack), offsetof(MatroskaDemuxContext,tracks), {.n=matroska_track} },
401     { 0 }
402 };
403
404 static EbmlSyntax matroska_attachment[] = {
405     { MATROSKA_ID_FILEUID,            EBML_UINT, 0, offsetof(MatroskaAttachement,uid) },
406     { MATROSKA_ID_FILENAME,           EBML_UTF8, 0, offsetof(MatroskaAttachement,filename) },
407     { MATROSKA_ID_FILEMIMETYPE,       EBML_STR,  0, offsetof(MatroskaAttachement,mime) },
408     { MATROSKA_ID_FILEDATA,           EBML_BIN,  0, offsetof(MatroskaAttachement,bin) },
409     { MATROSKA_ID_FILEDESC,           EBML_NONE },
410     { 0 }
411 };
412
413 static EbmlSyntax matroska_attachments[] = {
414     { MATROSKA_ID_ATTACHEDFILE,       EBML_NEST, sizeof(MatroskaAttachement), offsetof(MatroskaDemuxContext,attachments), {.n=matroska_attachment} },
415     { 0 }
416 };
417
418 static EbmlSyntax matroska_chapter_display[] = {
419     { MATROSKA_ID_CHAPSTRING,         EBML_UTF8, 0, offsetof(MatroskaChapter,title) },
420     { MATROSKA_ID_CHAPLANG,           EBML_NONE },
421     { 0 }
422 };
423
424 static EbmlSyntax matroska_chapter_entry[] = {
425     { MATROSKA_ID_CHAPTERTIMESTART,   EBML_UINT, 0, offsetof(MatroskaChapter,start), {.u=AV_NOPTS_VALUE} },
426     { MATROSKA_ID_CHAPTERTIMEEND,     EBML_UINT, 0, offsetof(MatroskaChapter,end), {.u=AV_NOPTS_VALUE} },
427     { MATROSKA_ID_CHAPTERUID,         EBML_UINT, 0, offsetof(MatroskaChapter,uid) },
428     { MATROSKA_ID_CHAPTERDISPLAY,     EBML_NEST, 0, 0, {.n=matroska_chapter_display} },
429     { MATROSKA_ID_CHAPTERFLAGHIDDEN,  EBML_NONE },
430     { MATROSKA_ID_CHAPTERFLAGENABLED, EBML_NONE },
431     { MATROSKA_ID_CHAPTERPHYSEQUIV,   EBML_NONE },
432     { MATROSKA_ID_CHAPTERATOM,        EBML_NONE },
433     { 0 }
434 };
435
436 static EbmlSyntax matroska_chapter[] = {
437     { MATROSKA_ID_CHAPTERATOM,        EBML_NEST, sizeof(MatroskaChapter), offsetof(MatroskaDemuxContext,chapters), {.n=matroska_chapter_entry} },
438     { MATROSKA_ID_EDITIONUID,         EBML_NONE },
439     { MATROSKA_ID_EDITIONFLAGHIDDEN,  EBML_NONE },
440     { MATROSKA_ID_EDITIONFLAGDEFAULT, EBML_NONE },
441     { MATROSKA_ID_EDITIONFLAGORDERED, EBML_NONE },
442     { 0 }
443 };
444
445 static EbmlSyntax matroska_chapters[] = {
446     { MATROSKA_ID_EDITIONENTRY,       EBML_NEST, 0, 0, {.n=matroska_chapter} },
447     { 0 }
448 };
449
450 static EbmlSyntax matroska_index_pos[] = {
451     { MATROSKA_ID_CUETRACK,           EBML_UINT, 0, offsetof(MatroskaIndexPos,track) },
452     { MATROSKA_ID_CUECLUSTERPOSITION, EBML_UINT, 0, offsetof(MatroskaIndexPos,pos)   },
453     { MATROSKA_ID_CUEBLOCKNUMBER,     EBML_NONE },
454     { 0 }
455 };
456
457 static EbmlSyntax matroska_index_entry[] = {
458     { MATROSKA_ID_CUETIME,            EBML_UINT, 0, offsetof(MatroskaIndex,time) },
459     { MATROSKA_ID_CUETRACKPOSITION,   EBML_NEST, sizeof(MatroskaIndexPos), offsetof(MatroskaIndex,pos), {.n=matroska_index_pos} },
460     { 0 }
461 };
462
463 static EbmlSyntax matroska_index[] = {
464     { MATROSKA_ID_POINTENTRY,         EBML_NEST, sizeof(MatroskaIndex), offsetof(MatroskaDemuxContext,index), {.n=matroska_index_entry} },
465     { 0 }
466 };
467
468 static EbmlSyntax matroska_simpletag[] = {
469     { MATROSKA_ID_TAGNAME,            EBML_UTF8, 0, offsetof(MatroskaTag,name) },
470     { MATROSKA_ID_TAGSTRING,          EBML_UTF8, 0, offsetof(MatroskaTag,string) },
471     { MATROSKA_ID_TAGLANG,            EBML_STR,  0, offsetof(MatroskaTag,lang), {.s="und"} },
472     { MATROSKA_ID_TAGDEFAULT,         EBML_UINT, 0, offsetof(MatroskaTag,def) },
473     { MATROSKA_ID_TAGDEFAULT_BUG,     EBML_UINT, 0, offsetof(MatroskaTag,def) },
474     { MATROSKA_ID_SIMPLETAG,          EBML_NEST, sizeof(MatroskaTag), offsetof(MatroskaTag,sub), {.n=matroska_simpletag} },
475     { 0 }
476 };
477
478 static EbmlSyntax matroska_tagtargets[] = {
479     { MATROSKA_ID_TAGTARGETS_TYPE,      EBML_STR,  0, offsetof(MatroskaTagTarget,type) },
480     { MATROSKA_ID_TAGTARGETS_TYPEVALUE, EBML_UINT, 0, offsetof(MatroskaTagTarget,typevalue), {.u=50} },
481     { MATROSKA_ID_TAGTARGETS_TRACKUID,  EBML_UINT, 0, offsetof(MatroskaTagTarget,trackuid) },
482     { MATROSKA_ID_TAGTARGETS_CHAPTERUID,EBML_UINT, 0, offsetof(MatroskaTagTarget,chapteruid) },
483     { MATROSKA_ID_TAGTARGETS_ATTACHUID, EBML_UINT, 0, offsetof(MatroskaTagTarget,attachuid) },
484     { 0 }
485 };
486
487 static EbmlSyntax matroska_tag[] = {
488     { MATROSKA_ID_SIMPLETAG,          EBML_NEST, sizeof(MatroskaTag), offsetof(MatroskaTags,tag), {.n=matroska_simpletag} },
489     { MATROSKA_ID_TAGTARGETS,         EBML_NEST, 0, offsetof(MatroskaTags,target), {.n=matroska_tagtargets} },
490     { 0 }
491 };
492
493 static EbmlSyntax matroska_tags[] = {
494     { MATROSKA_ID_TAG,                EBML_NEST, sizeof(MatroskaTags), offsetof(MatroskaDemuxContext,tags), {.n=matroska_tag} },
495     { 0 }
496 };
497
498 static EbmlSyntax matroska_seekhead_entry[] = {
499     { MATROSKA_ID_SEEKID,             EBML_UINT, 0, offsetof(MatroskaSeekhead,id) },
500     { MATROSKA_ID_SEEKPOSITION,       EBML_UINT, 0, offsetof(MatroskaSeekhead,pos), {.u=-1} },
501     { 0 }
502 };
503
504 static EbmlSyntax matroska_seekhead[] = {
505     { MATROSKA_ID_SEEKENTRY,          EBML_NEST, sizeof(MatroskaSeekhead), offsetof(MatroskaDemuxContext,seekhead), {.n=matroska_seekhead_entry} },
506     { 0 }
507 };
508
509 static EbmlSyntax matroska_segment[] = {
510     { MATROSKA_ID_INFO,           EBML_NEST, 0, 0, {.n=matroska_info       } },
511     { MATROSKA_ID_TRACKS,         EBML_NEST, 0, 0, {.n=matroska_tracks     } },
512     { MATROSKA_ID_ATTACHMENTS,    EBML_NEST, 0, 0, {.n=matroska_attachments} },
513     { MATROSKA_ID_CHAPTERS,       EBML_NEST, 0, 0, {.n=matroska_chapters   } },
514     { MATROSKA_ID_CUES,           EBML_NEST, 0, 0, {.n=matroska_index      } },
515     { MATROSKA_ID_TAGS,           EBML_NEST, 0, 0, {.n=matroska_tags       } },
516     { MATROSKA_ID_SEEKHEAD,       EBML_NEST, 0, 0, {.n=matroska_seekhead   } },
517     { MATROSKA_ID_CLUSTER,        EBML_STOP },
518     { 0 }
519 };
520
521 static EbmlSyntax matroska_segments[] = {
522     { MATROSKA_ID_SEGMENT,        EBML_NEST, 0, 0, {.n=matroska_segment    } },
523     { 0 }
524 };
525
526 static EbmlSyntax matroska_blockgroup[] = {
527     { MATROSKA_ID_BLOCK,          EBML_BIN,  0, offsetof(MatroskaBlock,bin) },
528     { MATROSKA_ID_SIMPLEBLOCK,    EBML_BIN,  0, offsetof(MatroskaBlock,bin) },
529     { MATROSKA_ID_BLOCKDURATION,  EBML_UINT, 0, offsetof(MatroskaBlock,duration) },
530     { MATROSKA_ID_BLOCKREFERENCE, EBML_UINT, 0, offsetof(MatroskaBlock,reference) },
531     { 1,                          EBML_UINT, 0, offsetof(MatroskaBlock,non_simple), {.u=1} },
532     { 0 }
533 };
534
535 static EbmlSyntax matroska_cluster[] = {
536     { MATROSKA_ID_CLUSTERTIMECODE,EBML_UINT,0, offsetof(MatroskaCluster,timecode) },
537     { MATROSKA_ID_BLOCKGROUP,     EBML_NEST, sizeof(MatroskaBlock), offsetof(MatroskaCluster,blocks), {.n=matroska_blockgroup} },
538     { MATROSKA_ID_SIMPLEBLOCK,    EBML_PASS, sizeof(MatroskaBlock), offsetof(MatroskaCluster,blocks), {.n=matroska_blockgroup} },
539     { MATROSKA_ID_CLUSTERPOSITION,EBML_NONE },
540     { MATROSKA_ID_CLUSTERPREVSIZE,EBML_NONE },
541     { 0 }
542 };
543
544 static EbmlSyntax matroska_clusters[] = {
545     { MATROSKA_ID_CLUSTER,        EBML_NEST, 0, 0, {.n=matroska_cluster} },
546     { MATROSKA_ID_INFO,           EBML_NONE },
547     { MATROSKA_ID_CUES,           EBML_NONE },
548     { MATROSKA_ID_TAGS,           EBML_NONE },
549     { MATROSKA_ID_SEEKHEAD,       EBML_NONE },
550     { 0 }
551 };
552
553 static EbmlSyntax matroska_cluster_incremental_parsing[] = {
554     { MATROSKA_ID_CLUSTERTIMECODE,EBML_UINT,0, offsetof(MatroskaCluster,timecode) },
555     { MATROSKA_ID_BLOCKGROUP,     EBML_NEST, sizeof(MatroskaBlock), offsetof(MatroskaCluster,blocks), {.n=matroska_blockgroup} },
556     { MATROSKA_ID_SIMPLEBLOCK,    EBML_PASS, sizeof(MatroskaBlock), offsetof(MatroskaCluster,blocks), {.n=matroska_blockgroup} },
557     { MATROSKA_ID_CLUSTERPOSITION,EBML_NONE },
558     { MATROSKA_ID_CLUSTERPREVSIZE,EBML_NONE },
559     { MATROSKA_ID_INFO,           EBML_NONE },
560     { MATROSKA_ID_CUES,           EBML_NONE },
561     { MATROSKA_ID_TAGS,           EBML_NONE },
562     { MATROSKA_ID_SEEKHEAD,       EBML_NONE },
563     { MATROSKA_ID_CLUSTER,        EBML_STOP },
564     { 0 }
565 };
566
567 static EbmlSyntax matroska_cluster_incremental[] = {
568     { MATROSKA_ID_CLUSTERTIMECODE,EBML_UINT,0, offsetof(MatroskaCluster,timecode) },
569     { MATROSKA_ID_BLOCKGROUP,     EBML_STOP },
570     { MATROSKA_ID_SIMPLEBLOCK,    EBML_STOP },
571     { MATROSKA_ID_CLUSTERPOSITION,EBML_NONE },
572     { MATROSKA_ID_CLUSTERPREVSIZE,EBML_NONE },
573     { 0 }
574 };
575
576 static EbmlSyntax matroska_clusters_incremental[] = {
577     { MATROSKA_ID_CLUSTER,        EBML_NEST, 0, 0, {.n=matroska_cluster_incremental} },
578     { MATROSKA_ID_INFO,           EBML_NONE },
579     { MATROSKA_ID_CUES,           EBML_NONE },
580     { MATROSKA_ID_TAGS,           EBML_NONE },
581     { MATROSKA_ID_SEEKHEAD,       EBML_NONE },
582     { 0 }
583 };
584
585 static const char *const matroska_doctypes[] = { "matroska", "webm" };
586
587 static int matroska_resync(MatroskaDemuxContext *matroska, int64_t last_pos)
588 {
589     AVIOContext *pb = matroska->ctx->pb;
590     uint32_t id;
591     matroska->current_id = 0;
592     matroska->num_levels = 0;
593
594     // seek to next position to resync from
595     if (avio_seek(pb, last_pos + 1, SEEK_SET) < 0 || avio_tell(pb) <= last_pos)
596         goto eof;
597
598     id = avio_rb32(pb);
599
600     // try to find a toplevel element
601     while (!url_feof(pb)) {
602         if (id == MATROSKA_ID_INFO || id == MATROSKA_ID_TRACKS ||
603             id == MATROSKA_ID_CUES || id == MATROSKA_ID_TAGS ||
604             id == MATROSKA_ID_SEEKHEAD || id == MATROSKA_ID_ATTACHMENTS ||
605             id == MATROSKA_ID_CLUSTER || id == MATROSKA_ID_CHAPTERS)
606         {
607             matroska->current_id = id;
608             return 0;
609         }
610         id = (id << 8) | avio_r8(pb);
611     }
612 eof:
613     matroska->done = 1;
614     return AVERROR_EOF;
615 }
616
617 /*
618  * Return: Whether we reached the end of a level in the hierarchy or not.
619  */
620 static int ebml_level_end(MatroskaDemuxContext *matroska)
621 {
622     AVIOContext *pb = matroska->ctx->pb;
623     int64_t pos = avio_tell(pb);
624
625     if (matroska->num_levels > 0) {
626         MatroskaLevel *level = &matroska->levels[matroska->num_levels - 1];
627         if (pos - level->start >= level->length || matroska->current_id) {
628             matroska->num_levels--;
629             return 1;
630         }
631     }
632     return 0;
633 }
634
635 /*
636  * Read: an "EBML number", which is defined as a variable-length
637  * array of bytes. The first byte indicates the length by giving a
638  * number of 0-bits followed by a one. The position of the first
639  * "one" bit inside the first byte indicates the length of this
640  * number.
641  * Returns: number of bytes read, < 0 on error
642  */
643 static int ebml_read_num(MatroskaDemuxContext *matroska, AVIOContext *pb,
644                          int max_size, uint64_t *number)
645 {
646     int read = 1, n = 1;
647     uint64_t total = 0;
648
649     /* The first byte tells us the length in bytes - avio_r8() can normally
650      * return 0, but since that's not a valid first ebmlID byte, we can
651      * use it safely here to catch EOS. */
652     if (!(total = avio_r8(pb))) {
653         /* we might encounter EOS here */
654         if (!url_feof(pb)) {
655             int64_t pos = avio_tell(pb);
656             av_log(matroska->ctx, AV_LOG_ERROR,
657                    "Read error at pos. %"PRIu64" (0x%"PRIx64")\n",
658                    pos, pos);
659             return pb->error ? pb->error : AVERROR(EIO);
660         }
661         return AVERROR_EOF;
662     }
663
664     /* get the length of the EBML number */
665     read = 8 - ff_log2_tab[total];
666     if (read > max_size) {
667         int64_t pos = avio_tell(pb) - 1;
668         av_log(matroska->ctx, AV_LOG_ERROR,
669                "Invalid EBML number size tag 0x%02x at pos %"PRIu64" (0x%"PRIx64")\n",
670                (uint8_t) total, pos, pos);
671         return AVERROR_INVALIDDATA;
672     }
673
674     /* read out length */
675     total ^= 1 << ff_log2_tab[total];
676     while (n++ < read)
677         total = (total << 8) | avio_r8(pb);
678
679     *number = total;
680
681     return read;
682 }
683
684 /**
685  * Read a EBML length value.
686  * This needs special handling for the "unknown length" case which has multiple
687  * encodings.
688  */
689 static int ebml_read_length(MatroskaDemuxContext *matroska, AVIOContext *pb,
690                             uint64_t *number)
691 {
692     int res = ebml_read_num(matroska, pb, 8, number);
693     if (res > 0 && *number + 1 == 1ULL << (7 * res))
694         *number = 0xffffffffffffffULL;
695     return res;
696 }
697
698 /*
699  * Read the next element as an unsigned int.
700  * 0 is success, < 0 is failure.
701  */
702 static int ebml_read_uint(AVIOContext *pb, int size, uint64_t *num)
703 {
704     int n = 0;
705
706     if (size > 8)
707         return AVERROR_INVALIDDATA;
708
709     /* big-endian ordering; build up number */
710     *num = 0;
711     while (n++ < size)
712         *num = (*num << 8) | avio_r8(pb);
713
714     return 0;
715 }
716
717 /*
718  * Read the next element as a float.
719  * 0 is success, < 0 is failure.
720  */
721 static int ebml_read_float(AVIOContext *pb, int size, double *num)
722 {
723     if (size == 0) {
724         *num = 0;
725     } else if (size == 4) {
726         *num = av_int2float(avio_rb32(pb));
727     } else if (size == 8){
728         *num = av_int2double(avio_rb64(pb));
729     } else
730         return AVERROR_INVALIDDATA;
731
732     return 0;
733 }
734
735 /*
736  * Read the next element as an ASCII string.
737  * 0 is success, < 0 is failure.
738  */
739 static int ebml_read_ascii(AVIOContext *pb, int size, char **str)
740 {
741     char *res;
742
743     /* EBML strings are usually not 0-terminated, so we allocate one
744      * byte more, read the string and NULL-terminate it ourselves. */
745     if (!(res = av_malloc(size + 1)))
746         return AVERROR(ENOMEM);
747     if (avio_read(pb, (uint8_t *) res, size) != size) {
748         av_free(res);
749         return AVERROR(EIO);
750     }
751     (res)[size] = '\0';
752     av_free(*str);
753     *str = res;
754
755     return 0;
756 }
757
758 /*
759  * Read the next element as binary data.
760  * 0 is success, < 0 is failure.
761  */
762 static int ebml_read_binary(AVIOContext *pb, int length, EbmlBin *bin)
763 {
764     av_free(bin->data);
765     if (!(bin->data = av_malloc(length)))
766         return AVERROR(ENOMEM);
767
768     bin->size = length;
769     bin->pos  = avio_tell(pb);
770     if (avio_read(pb, bin->data, length) != length) {
771         av_freep(&bin->data);
772         return AVERROR(EIO);
773     }
774
775     return 0;
776 }
777
778 /*
779  * Read the next element, but only the header. The contents
780  * are supposed to be sub-elements which can be read separately.
781  * 0 is success, < 0 is failure.
782  */
783 static int ebml_read_master(MatroskaDemuxContext *matroska, uint64_t length)
784 {
785     AVIOContext *pb = matroska->ctx->pb;
786     MatroskaLevel *level;
787
788     if (matroska->num_levels >= EBML_MAX_DEPTH) {
789         av_log(matroska->ctx, AV_LOG_ERROR,
790                "File moves beyond max. allowed depth (%d)\n", EBML_MAX_DEPTH);
791         return AVERROR(ENOSYS);
792     }
793
794     level = &matroska->levels[matroska->num_levels++];
795     level->start = avio_tell(pb);
796     level->length = length;
797
798     return 0;
799 }
800
801 /*
802  * Read signed/unsigned "EBML" numbers.
803  * Return: number of bytes processed, < 0 on error
804  */
805 static int matroska_ebmlnum_uint(MatroskaDemuxContext *matroska,
806                                  uint8_t *data, uint32_t size, uint64_t *num)
807 {
808     AVIOContext pb;
809     ffio_init_context(&pb, data, size, 0, NULL, NULL, NULL, NULL);
810     return ebml_read_num(matroska, &pb, FFMIN(size, 8), num);
811 }
812
813 /*
814  * Same as above, but signed.
815  */
816 static int matroska_ebmlnum_sint(MatroskaDemuxContext *matroska,
817                                  uint8_t *data, uint32_t size, int64_t *num)
818 {
819     uint64_t unum;
820     int res;
821
822     /* read as unsigned number first */
823     if ((res = matroska_ebmlnum_uint(matroska, data, size, &unum)) < 0)
824         return res;
825
826     /* make signed (weird way) */
827     *num = unum - ((1LL << (7*res - 1)) - 1);
828
829     return res;
830 }
831
832 static int ebml_parse_elem(MatroskaDemuxContext *matroska,
833                            EbmlSyntax *syntax, void *data);
834
835 static int ebml_parse_id(MatroskaDemuxContext *matroska, EbmlSyntax *syntax,
836                          uint32_t id, void *data)
837 {
838     int i;
839     for (i=0; syntax[i].id; i++)
840         if (id == syntax[i].id)
841             break;
842     if (!syntax[i].id && id == MATROSKA_ID_CLUSTER &&
843         matroska->num_levels > 0 &&
844         matroska->levels[matroska->num_levels-1].length == 0xffffffffffffff)
845         return 0;  // we reached the end of an unknown size cluster
846     if (!syntax[i].id && id != EBML_ID_VOID && id != EBML_ID_CRC32) {
847         av_log(matroska->ctx, AV_LOG_INFO, "Unknown entry 0x%X\n", id);
848         if (matroska->ctx->error_recognition & AV_EF_EXPLODE)
849             return AVERROR_INVALIDDATA;
850     }
851     return ebml_parse_elem(matroska, &syntax[i], data);
852 }
853
854 static int ebml_parse(MatroskaDemuxContext *matroska, EbmlSyntax *syntax,
855                       void *data)
856 {
857     if (!matroska->current_id) {
858         uint64_t id;
859         int res = ebml_read_num(matroska, matroska->ctx->pb, 4, &id);
860         if (res < 0)
861             return res;
862         matroska->current_id = id | 1 << 7*res;
863     }
864     return ebml_parse_id(matroska, syntax, matroska->current_id, data);
865 }
866
867 static int ebml_parse_nest(MatroskaDemuxContext *matroska, EbmlSyntax *syntax,
868                            void *data)
869 {
870     int i, res = 0;
871
872     for (i=0; syntax[i].id; i++)
873         switch (syntax[i].type) {
874         case EBML_UINT:
875             *(uint64_t *)((char *)data+syntax[i].data_offset) = syntax[i].def.u;
876             break;
877         case EBML_FLOAT:
878             *(double   *)((char *)data+syntax[i].data_offset) = syntax[i].def.f;
879             break;
880         case EBML_STR:
881         case EBML_UTF8:
882             *(char    **)((char *)data+syntax[i].data_offset) = av_strdup(syntax[i].def.s);
883             break;
884         }
885
886     while (!res && !ebml_level_end(matroska))
887         res = ebml_parse(matroska, syntax, data);
888
889     return res;
890 }
891
892 static int ebml_parse_elem(MatroskaDemuxContext *matroska,
893                            EbmlSyntax *syntax, void *data)
894 {
895     static const uint64_t max_lengths[EBML_TYPE_COUNT] = {
896         [EBML_UINT]  = 8,
897         [EBML_FLOAT] = 8,
898         // max. 16 MB for strings
899         [EBML_STR]   = 0x1000000,
900         [EBML_UTF8]  = 0x1000000,
901         // max. 256 MB for binary data
902         [EBML_BIN]   = 0x10000000,
903         // no limits for anything else
904     };
905     AVIOContext *pb = matroska->ctx->pb;
906     uint32_t id = syntax->id;
907     uint64_t length;
908     int res;
909     void *newelem;
910
911     data = (char *)data + syntax->data_offset;
912     if (syntax->list_elem_size) {
913         EbmlList *list = data;
914         newelem = av_realloc(list->elem, (list->nb_elem+1)*syntax->list_elem_size);
915         if (!newelem)
916             return AVERROR(ENOMEM);
917         list->elem = newelem;
918         data = (char*)list->elem + list->nb_elem*syntax->list_elem_size;
919         memset(data, 0, syntax->list_elem_size);
920         list->nb_elem++;
921     }
922
923     if (syntax->type != EBML_PASS && syntax->type != EBML_STOP) {
924         matroska->current_id = 0;
925         if ((res = ebml_read_length(matroska, pb, &length)) < 0)
926             return res;
927         if (max_lengths[syntax->type] && length > max_lengths[syntax->type]) {
928             av_log(matroska->ctx, AV_LOG_ERROR,
929                    "Invalid length 0x%"PRIx64" > 0x%"PRIx64" for syntax element %i\n",
930                    length, max_lengths[syntax->type], syntax->type);
931             return AVERROR_INVALIDDATA;
932         }
933     }
934
935     switch (syntax->type) {
936     case EBML_UINT:  res = ebml_read_uint  (pb, length, data);  break;
937     case EBML_FLOAT: res = ebml_read_float (pb, length, data);  break;
938     case EBML_STR:
939     case EBML_UTF8:  res = ebml_read_ascii (pb, length, data);  break;
940     case EBML_BIN:   res = ebml_read_binary(pb, length, data);  break;
941     case EBML_NEST:  if ((res=ebml_read_master(matroska, length)) < 0)
942                          return res;
943                      if (id == MATROSKA_ID_SEGMENT)
944                          matroska->segment_start = avio_tell(matroska->ctx->pb);
945                      return ebml_parse_nest(matroska, syntax->def.n, data);
946     case EBML_PASS:  return ebml_parse_id(matroska, syntax->def.n, id, data);
947     case EBML_STOP:  return 1;
948     default:
949         if(ffio_limit(pb, length) != length)
950             return AVERROR(EIO);
951         return avio_skip(pb,length)<0 ? AVERROR(EIO) : 0;
952     }
953     if (res == AVERROR_INVALIDDATA)
954         av_log(matroska->ctx, AV_LOG_ERROR, "Invalid element\n");
955     else if (res == AVERROR(EIO))
956         av_log(matroska->ctx, AV_LOG_ERROR, "Read error\n");
957     return res;
958 }
959
960 static void ebml_free(EbmlSyntax *syntax, void *data)
961 {
962     int i, j;
963     for (i=0; syntax[i].id; i++) {
964         void *data_off = (char *)data + syntax[i].data_offset;
965         switch (syntax[i].type) {
966         case EBML_STR:
967         case EBML_UTF8:  av_freep(data_off);                      break;
968         case EBML_BIN:   av_freep(&((EbmlBin *)data_off)->data);  break;
969         case EBML_NEST:
970             if (syntax[i].list_elem_size) {
971                 EbmlList *list = data_off;
972                 char *ptr = list->elem;
973                 for (j=0; j<list->nb_elem; j++, ptr+=syntax[i].list_elem_size)
974                     ebml_free(syntax[i].def.n, ptr);
975                 av_free(list->elem);
976             } else
977                 ebml_free(syntax[i].def.n, data_off);
978         default:  break;
979         }
980     }
981 }
982
983
984 /*
985  * Autodetecting...
986  */
987 static int matroska_probe(AVProbeData *p)
988 {
989     uint64_t total = 0;
990     int len_mask = 0x80, size = 1, n = 1, i;
991
992     /* EBML header? */
993     if (AV_RB32(p->buf) != EBML_ID_HEADER)
994         return 0;
995
996     /* length of header */
997     total = p->buf[4];
998     while (size <= 8 && !(total & len_mask)) {
999         size++;
1000         len_mask >>= 1;
1001     }
1002     if (size > 8)
1003       return 0;
1004     total &= (len_mask - 1);
1005     while (n < size)
1006         total = (total << 8) | p->buf[4 + n++];
1007
1008     /* Does the probe data contain the whole header? */
1009     if (p->buf_size < 4 + size + total)
1010       return 0;
1011
1012     /* The header should contain a known document type. For now,
1013      * we don't parse the whole header but simply check for the
1014      * availability of that array of characters inside the header.
1015      * Not fully fool-proof, but good enough. */
1016     for (i = 0; i < FF_ARRAY_ELEMS(matroska_doctypes); i++) {
1017         int probelen = strlen(matroska_doctypes[i]);
1018         if (total < probelen)
1019             continue;
1020         for (n = 4+size; n <= 4+size+total-probelen; n++)
1021             if (!memcmp(p->buf+n, matroska_doctypes[i], probelen))
1022                 return AVPROBE_SCORE_MAX;
1023     }
1024
1025     // probably valid EBML header but no recognized doctype
1026     return AVPROBE_SCORE_MAX/2;
1027 }
1028
1029 static MatroskaTrack *matroska_find_track_by_num(MatroskaDemuxContext *matroska,
1030                                                  int num)
1031 {
1032     MatroskaTrack *tracks = matroska->tracks.elem;
1033     int i;
1034
1035     for (i=0; i < matroska->tracks.nb_elem; i++)
1036         if (tracks[i].num == num)
1037             return &tracks[i];
1038
1039     av_log(matroska->ctx, AV_LOG_ERROR, "Invalid track number %d\n", num);
1040     return NULL;
1041 }
1042
1043 static int matroska_decode_buffer(uint8_t** buf, int* buf_size,
1044                                   MatroskaTrack *track)
1045 {
1046     MatroskaTrackEncoding *encodings = track->encodings.elem;
1047     uint8_t* data = *buf;
1048     int isize = *buf_size;
1049     uint8_t* pkt_data = NULL;
1050     uint8_t av_unused *newpktdata;
1051     int pkt_size = isize;
1052     int result = 0;
1053     int olen;
1054
1055     if (pkt_size >= 10000000U)
1056         return -1;
1057
1058     switch (encodings[0].compression.algo) {
1059     case MATROSKA_TRACK_ENCODING_COMP_HEADERSTRIP:
1060         if (encodings[0].compression.settings.size && !encodings[0].compression.settings.data) {
1061             av_log(0, AV_LOG_ERROR, "Compression size but no data in headerstrip\n");
1062             return -1;
1063         }
1064         return encodings[0].compression.settings.size;
1065     case MATROSKA_TRACK_ENCODING_COMP_LZO:
1066         do {
1067             olen = pkt_size *= 3;
1068             pkt_data = av_realloc(pkt_data, pkt_size+AV_LZO_OUTPUT_PADDING);
1069             result = av_lzo1x_decode(pkt_data, &olen, data, &isize);
1070         } while (result==AV_LZO_OUTPUT_FULL && pkt_size<10000000);
1071         if (result)
1072             goto failed;
1073         pkt_size -= olen;
1074         break;
1075 #if CONFIG_ZLIB
1076     case MATROSKA_TRACK_ENCODING_COMP_ZLIB: {
1077         z_stream zstream = {0};
1078         if (inflateInit(&zstream) != Z_OK)
1079             return -1;
1080         zstream.next_in = data;
1081         zstream.avail_in = isize;
1082         do {
1083             pkt_size *= 3;
1084             newpktdata = av_realloc(pkt_data, pkt_size);
1085             if (!newpktdata) {
1086                 inflateEnd(&zstream);
1087                 goto failed;
1088             }
1089             pkt_data = newpktdata;
1090             zstream.avail_out = pkt_size - zstream.total_out;
1091             zstream.next_out = pkt_data + zstream.total_out;
1092             if (pkt_data) {
1093                 result = inflate(&zstream, Z_NO_FLUSH);
1094             } else
1095                 result = Z_MEM_ERROR;
1096         } while (result==Z_OK && pkt_size<10000000);
1097         pkt_size = zstream.total_out;
1098         inflateEnd(&zstream);
1099         if (result != Z_STREAM_END)
1100             goto failed;
1101         break;
1102     }
1103 #endif
1104 #if CONFIG_BZLIB
1105     case MATROSKA_TRACK_ENCODING_COMP_BZLIB: {
1106         bz_stream bzstream = {0};
1107         if (BZ2_bzDecompressInit(&bzstream, 0, 0) != BZ_OK)
1108             return -1;
1109         bzstream.next_in = data;
1110         bzstream.avail_in = isize;
1111         do {
1112             pkt_size *= 3;
1113             newpktdata = av_realloc(pkt_data, pkt_size);
1114             if (!newpktdata) {
1115                 BZ2_bzDecompressEnd(&bzstream);
1116                 goto failed;
1117             }
1118             pkt_data = newpktdata;
1119             bzstream.avail_out = pkt_size - bzstream.total_out_lo32;
1120             bzstream.next_out = pkt_data + bzstream.total_out_lo32;
1121             if (pkt_data) {
1122                 result = BZ2_bzDecompress(&bzstream);
1123             } else
1124                 result = BZ_MEM_ERROR;
1125         } while (result==BZ_OK && pkt_size<10000000);
1126         pkt_size = bzstream.total_out_lo32;
1127         BZ2_bzDecompressEnd(&bzstream);
1128         if (result != BZ_STREAM_END)
1129             goto failed;
1130         break;
1131     }
1132 #endif
1133     default:
1134         return -1;
1135     }
1136
1137     *buf = pkt_data;
1138     *buf_size = pkt_size;
1139     return 0;
1140  failed:
1141     av_free(pkt_data);
1142     return -1;
1143 }
1144
1145 static void matroska_fix_ass_packet(MatroskaDemuxContext *matroska,
1146                                     AVPacket *pkt, uint64_t display_duration)
1147 {
1148     char *line, *layer, *ptr = pkt->data, *end = ptr+pkt->size;
1149     for (; *ptr!=',' && ptr<end-1; ptr++);
1150     if (*ptr == ',')
1151         ptr++;
1152     layer = ptr;
1153     for (; *ptr!=',' && ptr<end-1; ptr++);
1154     if (*ptr == ',') {
1155         int64_t end_pts = pkt->pts + display_duration;
1156         int sc = matroska->time_scale * pkt->pts / 10000000;
1157         int ec = matroska->time_scale * end_pts  / 10000000;
1158         int sh, sm, ss, eh, em, es, len;
1159         sh = sc/360000;  sc -= 360000*sh;
1160         sm = sc/  6000;  sc -=   6000*sm;
1161         ss = sc/   100;  sc -=    100*ss;
1162         eh = ec/360000;  ec -= 360000*eh;
1163         em = ec/  6000;  ec -=   6000*em;
1164         es = ec/   100;  ec -=    100*es;
1165         *ptr++ = '\0';
1166         len = 50 + end-ptr + FF_INPUT_BUFFER_PADDING_SIZE;
1167         if (!(line = av_malloc(len)))
1168             return;
1169         snprintf(line,len,"Dialogue: %s,%d:%02d:%02d.%02d,%d:%02d:%02d.%02d,%s\r\n",
1170                  layer, sh, sm, ss, sc, eh, em, es, ec, ptr);
1171         av_free(pkt->data);
1172         pkt->data = line;
1173         pkt->size = strlen(line);
1174     }
1175 }
1176
1177 static int matroska_merge_packets(AVPacket *out, AVPacket *in)
1178 {
1179     int ret = av_grow_packet(out, in->size);
1180     if (ret < 0)
1181         return ret;
1182     memcpy(out->data + out->size - in->size, in->data, in->size);
1183     av_destruct_packet(in);
1184     av_free(in);
1185     return 0;
1186 }
1187
1188 static void matroska_convert_tag(AVFormatContext *s, EbmlList *list,
1189                                  AVDictionary **metadata, char *prefix)
1190 {
1191     MatroskaTag *tags = list->elem;
1192     char key[1024];
1193     int i;
1194
1195     for (i=0; i < list->nb_elem; i++) {
1196         const char *lang= (tags[i].lang && strcmp(tags[i].lang, "und")) ? tags[i].lang : NULL;
1197
1198         if (!tags[i].name) {
1199             av_log(s, AV_LOG_WARNING, "Skipping invalid tag with no TagName.\n");
1200             continue;
1201         }
1202         if (prefix)  snprintf(key, sizeof(key), "%s/%s", prefix, tags[i].name);
1203         else         av_strlcpy(key, tags[i].name, sizeof(key));
1204         if (tags[i].def || !lang) {
1205         av_dict_set(metadata, key, tags[i].string, 0);
1206         if (tags[i].sub.nb_elem)
1207             matroska_convert_tag(s, &tags[i].sub, metadata, key);
1208         }
1209         if (lang) {
1210             av_strlcat(key, "-", sizeof(key));
1211             av_strlcat(key, lang, sizeof(key));
1212             av_dict_set(metadata, key, tags[i].string, 0);
1213             if (tags[i].sub.nb_elem)
1214                 matroska_convert_tag(s, &tags[i].sub, metadata, key);
1215         }
1216     }
1217     ff_metadata_conv(metadata, NULL, ff_mkv_metadata_conv);
1218 }
1219
1220 static void matroska_convert_tags(AVFormatContext *s)
1221 {
1222     MatroskaDemuxContext *matroska = s->priv_data;
1223     MatroskaTags *tags = matroska->tags.elem;
1224     int i, j;
1225
1226     for (i=0; i < matroska->tags.nb_elem; i++) {
1227         if (tags[i].target.attachuid) {
1228             MatroskaAttachement *attachment = matroska->attachments.elem;
1229             for (j=0; j<matroska->attachments.nb_elem; j++)
1230                 if (attachment[j].uid == tags[i].target.attachuid
1231                     && attachment[j].stream)
1232                     matroska_convert_tag(s, &tags[i].tag,
1233                                          &attachment[j].stream->metadata, NULL);
1234         } else if (tags[i].target.chapteruid) {
1235             MatroskaChapter *chapter = matroska->chapters.elem;
1236             for (j=0; j<matroska->chapters.nb_elem; j++)
1237                 if (chapter[j].uid == tags[i].target.chapteruid
1238                     && chapter[j].chapter)
1239                     matroska_convert_tag(s, &tags[i].tag,
1240                                          &chapter[j].chapter->metadata, NULL);
1241         } else if (tags[i].target.trackuid) {
1242             MatroskaTrack *track = matroska->tracks.elem;
1243             for (j=0; j<matroska->tracks.nb_elem; j++)
1244                 if (track[j].uid == tags[i].target.trackuid && track[j].stream)
1245                     matroska_convert_tag(s, &tags[i].tag,
1246                                          &track[j].stream->metadata, NULL);
1247         } else {
1248             matroska_convert_tag(s, &tags[i].tag, &s->metadata,
1249                                  tags[i].target.type);
1250         }
1251     }
1252 }
1253
1254 static int matroska_parse_seekhead_entry(MatroskaDemuxContext *matroska, int idx)
1255 {
1256     EbmlList *seekhead_list = &matroska->seekhead;
1257     MatroskaSeekhead *seekhead = seekhead_list->elem;
1258     uint32_t level_up = matroska->level_up;
1259     int64_t before_pos = avio_tell(matroska->ctx->pb);
1260     uint32_t saved_id = matroska->current_id;
1261     MatroskaLevel level;
1262     int64_t offset;
1263     int ret = 0;
1264
1265     if (idx >= seekhead_list->nb_elem
1266             || seekhead[idx].id == MATROSKA_ID_SEEKHEAD
1267             || seekhead[idx].id == MATROSKA_ID_CLUSTER)
1268         return 0;
1269
1270     /* seek */
1271     offset = seekhead[idx].pos + matroska->segment_start;
1272     if (avio_seek(matroska->ctx->pb, offset, SEEK_SET) == offset) {
1273         /* We don't want to lose our seekhead level, so we add
1274          * a dummy. This is a crude hack. */
1275         if (matroska->num_levels == EBML_MAX_DEPTH) {
1276             av_log(matroska->ctx, AV_LOG_INFO,
1277                    "Max EBML element depth (%d) reached, "
1278                    "cannot parse further.\n", EBML_MAX_DEPTH);
1279             ret = AVERROR_INVALIDDATA;
1280         } else {
1281             level.start = 0;
1282             level.length = (uint64_t)-1;
1283             matroska->levels[matroska->num_levels] = level;
1284             matroska->num_levels++;
1285             matroska->current_id = 0;
1286
1287             ret = ebml_parse(matroska, matroska_segment, matroska);
1288
1289             /* remove dummy level */
1290             while (matroska->num_levels) {
1291                 uint64_t length = matroska->levels[--matroska->num_levels].length;
1292                 if (length == (uint64_t)-1)
1293                     break;
1294             }
1295         }
1296     }
1297     /* seek back */
1298     avio_seek(matroska->ctx->pb, before_pos, SEEK_SET);
1299     matroska->level_up = level_up;
1300     matroska->current_id = saved_id;
1301
1302     return ret;
1303 }
1304
1305 static void matroska_execute_seekhead(MatroskaDemuxContext *matroska)
1306 {
1307     EbmlList *seekhead_list = &matroska->seekhead;
1308     int64_t before_pos = avio_tell(matroska->ctx->pb);
1309     int i;
1310
1311     // we should not do any seeking in the streaming case
1312     if (!matroska->ctx->pb->seekable ||
1313         (matroska->ctx->flags & AVFMT_FLAG_IGNIDX))
1314         return;
1315
1316     for (i = 0; i < seekhead_list->nb_elem; i++) {
1317         MatroskaSeekhead *seekhead = seekhead_list->elem;
1318         if (seekhead[i].pos <= before_pos)
1319             continue;
1320
1321         // defer cues parsing until we actually need cue data.
1322         if (seekhead[i].id == MATROSKA_ID_CUES) {
1323             matroska->cues_parsing_deferred = 1;
1324             continue;
1325         }
1326
1327         if (matroska_parse_seekhead_entry(matroska, i) < 0) {
1328             // mark index as broken
1329             matroska->cues_parsing_deferred = -1;
1330             break;
1331         }
1332     }
1333 }
1334
1335 static void matroska_add_index_entries(MatroskaDemuxContext *matroska) {
1336     EbmlList *index_list;
1337     MatroskaIndex *index;
1338     int index_scale = 1;
1339     int i, j;
1340
1341     index_list = &matroska->index;
1342     index = index_list->elem;
1343     if (index_list->nb_elem
1344         && index[0].time > 1E14/matroska->time_scale) {
1345         av_log(matroska->ctx, AV_LOG_WARNING, "Working around broken index.\n");
1346         index_scale = matroska->time_scale;
1347     }
1348     for (i = 0; i < index_list->nb_elem; i++) {
1349         EbmlList *pos_list = &index[i].pos;
1350         MatroskaIndexPos *pos = pos_list->elem;
1351         for (j = 0; j < pos_list->nb_elem; j++) {
1352             MatroskaTrack *track = matroska_find_track_by_num(matroska, pos[j].track);
1353             if (track && track->stream)
1354                 av_add_index_entry(track->stream,
1355                                    pos[j].pos + matroska->segment_start,
1356                                    index[i].time/index_scale, 0, 0,
1357                                    AVINDEX_KEYFRAME);
1358         }
1359     }
1360 }
1361
1362 static void matroska_parse_cues(MatroskaDemuxContext *matroska) {
1363     EbmlList *seekhead_list = &matroska->seekhead;
1364     MatroskaSeekhead *seekhead = seekhead_list->elem;
1365     int i;
1366
1367     for (i = 0; i < seekhead_list->nb_elem; i++)
1368         if (seekhead[i].id == MATROSKA_ID_CUES)
1369             break;
1370     assert(i <= seekhead_list->nb_elem);
1371
1372     if (matroska_parse_seekhead_entry(matroska, i) < 0)
1373        matroska->cues_parsing_deferred = -1;
1374     matroska_add_index_entries(matroska);
1375 }
1376
1377 static int matroska_aac_profile(char *codec_id)
1378 {
1379     static const char * const aac_profiles[] = { "MAIN", "LC", "SSR" };
1380     int profile;
1381
1382     for (profile=0; profile<FF_ARRAY_ELEMS(aac_profiles); profile++)
1383         if (strstr(codec_id, aac_profiles[profile]))
1384             break;
1385     return profile + 1;
1386 }
1387
1388 static int matroska_aac_sri(int samplerate)
1389 {
1390     int sri;
1391
1392     for (sri=0; sri<FF_ARRAY_ELEMS(avpriv_mpeg4audio_sample_rates); sri++)
1393         if (avpriv_mpeg4audio_sample_rates[sri] == samplerate)
1394             break;
1395     return sri;
1396 }
1397
1398 static void matroska_metadata_creation_time(AVDictionary **metadata, int64_t date_utc)
1399 {
1400     char buffer[32];
1401     /* Convert to seconds and adjust by number of seconds between 2001-01-01 and Epoch */
1402     time_t creation_time = date_utc / 1000000000 + 978307200;
1403     struct tm *ptm = gmtime(&creation_time);
1404     if (!ptm) return;
1405     strftime(buffer, sizeof(buffer), "%Y-%m-%d %H:%M:%S", ptm);
1406     av_dict_set(metadata, "creation_time", buffer, 0);
1407 }
1408
1409 static int matroska_read_header(AVFormatContext *s)
1410 {
1411     MatroskaDemuxContext *matroska = s->priv_data;
1412     EbmlList *attachements_list = &matroska->attachments;
1413     MatroskaAttachement *attachements;
1414     EbmlList *chapters_list = &matroska->chapters;
1415     MatroskaChapter *chapters;
1416     MatroskaTrack *tracks;
1417     uint64_t max_start = 0;
1418     int64_t pos;
1419     Ebml ebml = { 0 };
1420     AVStream *st;
1421     int i, j, k, res;
1422
1423     matroska->ctx = s;
1424
1425     /* First read the EBML header. */
1426     if (ebml_parse(matroska, ebml_syntax, &ebml)
1427         || ebml.version > EBML_VERSION       || ebml.max_size > sizeof(uint64_t)
1428         || ebml.id_length > sizeof(uint32_t) || ebml.doctype_version > 3 || !ebml.doctype) {
1429         av_log(matroska->ctx, AV_LOG_ERROR,
1430                "EBML header using unsupported features\n"
1431                "(EBML version %"PRIu64", doctype %s, doc version %"PRIu64")\n",
1432                ebml.version, ebml.doctype, ebml.doctype_version);
1433         ebml_free(ebml_syntax, &ebml);
1434         return AVERROR_PATCHWELCOME;
1435     } else if (ebml.doctype_version == 3) {
1436         av_log(matroska->ctx, AV_LOG_WARNING,
1437                "EBML header using unsupported features\n"
1438                "(EBML version %"PRIu64", doctype %s, doc version %"PRIu64")\n",
1439                ebml.version, ebml.doctype, ebml.doctype_version);
1440     }
1441     for (i = 0; i < FF_ARRAY_ELEMS(matroska_doctypes); i++)
1442         if (!strcmp(ebml.doctype, matroska_doctypes[i]))
1443             break;
1444     if (i >= FF_ARRAY_ELEMS(matroska_doctypes)) {
1445         av_log(s, AV_LOG_WARNING, "Unknown EBML doctype '%s'\n", ebml.doctype);
1446     }
1447     ebml_free(ebml_syntax, &ebml);
1448
1449     /* The next thing is a segment. */
1450     pos = avio_tell(matroska->ctx->pb);
1451     res = ebml_parse(matroska, matroska_segments, matroska);
1452     // try resyncing until we find a EBML_STOP type element.
1453     while (res != 1) {
1454         res = matroska_resync(matroska, pos);
1455         if (res < 0)
1456             return res;
1457         pos = avio_tell(matroska->ctx->pb);
1458         res = ebml_parse(matroska, matroska_segment, matroska);
1459     }
1460     matroska_execute_seekhead(matroska);
1461
1462     if (!matroska->time_scale)
1463         matroska->time_scale = 1000000;
1464     if (matroska->duration)
1465         matroska->ctx->duration = matroska->duration * matroska->time_scale
1466                                   * 1000 / AV_TIME_BASE;
1467     av_dict_set(&s->metadata, "title", matroska->title, 0);
1468
1469     if (matroska->date_utc.size == 8)
1470         matroska_metadata_creation_time(&s->metadata, AV_RB64(matroska->date_utc.data));
1471
1472     tracks = matroska->tracks.elem;
1473     for (i=0; i < matroska->tracks.nb_elem; i++) {
1474         MatroskaTrack *track = &tracks[i];
1475         enum AVCodecID codec_id = AV_CODEC_ID_NONE;
1476         EbmlList *encodings_list = &track->encodings;
1477         MatroskaTrackEncoding *encodings = encodings_list->elem;
1478         uint8_t *extradata = NULL;
1479         int extradata_size = 0;
1480         int extradata_offset = 0;
1481         uint32_t fourcc = 0;
1482         AVIOContext b;
1483
1484         /* Apply some sanity checks. */
1485         if (track->type != MATROSKA_TRACK_TYPE_VIDEO &&
1486             track->type != MATROSKA_TRACK_TYPE_AUDIO &&
1487             track->type != MATROSKA_TRACK_TYPE_SUBTITLE) {
1488             av_log(matroska->ctx, AV_LOG_INFO,
1489                    "Unknown or unsupported track type %"PRIu64"\n",
1490                    track->type);
1491             continue;
1492         }
1493         if (track->codec_id == NULL)
1494             continue;
1495
1496         if (track->type == MATROSKA_TRACK_TYPE_VIDEO) {
1497             if (!track->default_duration && track->video.frame_rate > 0)
1498                 track->default_duration = 1000000000/track->video.frame_rate;
1499             if (!track->video.display_width)
1500                 track->video.display_width = track->video.pixel_width;
1501             if (!track->video.display_height)
1502                 track->video.display_height = track->video.pixel_height;
1503             if (track->video.color_space.size == 4)
1504                 fourcc = AV_RL32(track->video.color_space.data);
1505         } else if (track->type == MATROSKA_TRACK_TYPE_AUDIO) {
1506             if (!track->audio.out_samplerate)
1507                 track->audio.out_samplerate = track->audio.samplerate;
1508         }
1509         if (encodings_list->nb_elem > 1) {
1510             av_log(matroska->ctx, AV_LOG_ERROR,
1511                    "Multiple combined encodings not supported");
1512         } else if (encodings_list->nb_elem == 1) {
1513             if (encodings[0].type ||
1514                 (encodings[0].compression.algo != MATROSKA_TRACK_ENCODING_COMP_HEADERSTRIP &&
1515 #if CONFIG_ZLIB
1516                  encodings[0].compression.algo != MATROSKA_TRACK_ENCODING_COMP_ZLIB &&
1517 #endif
1518 #if CONFIG_BZLIB
1519                  encodings[0].compression.algo != MATROSKA_TRACK_ENCODING_COMP_BZLIB &&
1520 #endif
1521                  encodings[0].compression.algo != MATROSKA_TRACK_ENCODING_COMP_LZO)) {
1522                 encodings[0].scope = 0;
1523                 av_log(matroska->ctx, AV_LOG_ERROR,
1524                        "Unsupported encoding type");
1525             } else if (track->codec_priv.size && encodings[0].scope&2) {
1526                 uint8_t *codec_priv = track->codec_priv.data;
1527                 int offset = matroska_decode_buffer(&track->codec_priv.data,
1528                                                     &track->codec_priv.size,
1529                                                     track);
1530                 if (offset < 0) {
1531                     track->codec_priv.data = NULL;
1532                     track->codec_priv.size = 0;
1533                     av_log(matroska->ctx, AV_LOG_ERROR,
1534                            "Failed to decode codec private data\n");
1535                 } else if (offset > 0) {
1536                     track->codec_priv.data = av_malloc(track->codec_priv.size + offset);
1537                     memcpy(track->codec_priv.data,
1538                            encodings[0].compression.settings.data, offset);
1539                     memcpy(track->codec_priv.data+offset, codec_priv,
1540                            track->codec_priv.size);
1541                     track->codec_priv.size += offset;
1542                 }
1543                 if (codec_priv != track->codec_priv.data)
1544                     av_free(codec_priv);
1545             }
1546         }
1547
1548         for(j=0; ff_mkv_codec_tags[j].id != AV_CODEC_ID_NONE; j++){
1549             if(!strncmp(ff_mkv_codec_tags[j].str, track->codec_id,
1550                         strlen(ff_mkv_codec_tags[j].str))){
1551                 codec_id= ff_mkv_codec_tags[j].id;
1552                 break;
1553             }
1554         }
1555
1556         st = track->stream = avformat_new_stream(s, NULL);
1557         if (st == NULL)
1558             return AVERROR(ENOMEM);
1559
1560         if (!strcmp(track->codec_id, "V_MS/VFW/FOURCC")
1561             && track->codec_priv.size >= 40
1562             && track->codec_priv.data != NULL) {
1563             track->ms_compat = 1;
1564             fourcc = AV_RL32(track->codec_priv.data + 16);
1565             codec_id = ff_codec_get_id(ff_codec_bmp_tags, fourcc);
1566             extradata_offset = 40;
1567         } else if (!strcmp(track->codec_id, "A_MS/ACM")
1568                    && track->codec_priv.size >= 14
1569                    && track->codec_priv.data != NULL) {
1570             int ret;
1571             ffio_init_context(&b, track->codec_priv.data, track->codec_priv.size,
1572                           AVIO_FLAG_READ, NULL, NULL, NULL, NULL);
1573             ret = ff_get_wav_header(&b, st->codec, track->codec_priv.size);
1574             if (ret < 0)
1575                 return ret;
1576             codec_id = st->codec->codec_id;
1577             extradata_offset = FFMIN(track->codec_priv.size, 18);
1578         } else if (!strcmp(track->codec_id, "V_QUICKTIME")
1579                    && (track->codec_priv.size >= 86)
1580                    && (track->codec_priv.data != NULL)) {
1581             fourcc = AV_RL32(track->codec_priv.data);
1582             codec_id = ff_codec_get_id(ff_codec_movvideo_tags, fourcc);
1583         } else if (codec_id == AV_CODEC_ID_ALAC && track->codec_priv.size && track->codec_priv.size < INT_MAX-12) {
1584             /* Only ALAC's magic cookie is stored in Matroska's track headers.
1585                Create the "atom size", "tag", and "tag version" fields the
1586                decoder expects manually. */
1587             extradata_size = 12 + track->codec_priv.size;
1588             extradata = av_mallocz(extradata_size);
1589             if (extradata == NULL)
1590                 return AVERROR(ENOMEM);
1591             AV_WB32(extradata, extradata_size);
1592             memcpy(&extradata[4], "alac", 4);
1593             AV_WB32(&extradata[8], 0);
1594             memcpy(&extradata[12], track->codec_priv.data, track->codec_priv.size);
1595         } else if (codec_id == AV_CODEC_ID_PCM_S16BE) {
1596             switch (track->audio.bitdepth) {
1597             case  8:  codec_id = AV_CODEC_ID_PCM_U8;     break;
1598             case 24:  codec_id = AV_CODEC_ID_PCM_S24BE;  break;
1599             case 32:  codec_id = AV_CODEC_ID_PCM_S32BE;  break;
1600             }
1601         } else if (codec_id == AV_CODEC_ID_PCM_S16LE) {
1602             switch (track->audio.bitdepth) {
1603             case  8:  codec_id = AV_CODEC_ID_PCM_U8;     break;
1604             case 24:  codec_id = AV_CODEC_ID_PCM_S24LE;  break;
1605             case 32:  codec_id = AV_CODEC_ID_PCM_S32LE;  break;
1606             }
1607         } else if (codec_id==AV_CODEC_ID_PCM_F32LE && track->audio.bitdepth==64) {
1608             codec_id = AV_CODEC_ID_PCM_F64LE;
1609         } else if (codec_id == AV_CODEC_ID_AAC && !track->codec_priv.size) {
1610             int profile = matroska_aac_profile(track->codec_id);
1611             int sri = matroska_aac_sri(track->audio.samplerate);
1612             extradata = av_mallocz(5 + FF_INPUT_BUFFER_PADDING_SIZE);
1613             if (extradata == NULL)
1614                 return AVERROR(ENOMEM);
1615             extradata[0] = (profile << 3) | ((sri&0x0E) >> 1);
1616             extradata[1] = ((sri&0x01) << 7) | (track->audio.channels<<3);
1617             if (strstr(track->codec_id, "SBR")) {
1618                 sri = matroska_aac_sri(track->audio.out_samplerate);
1619                 extradata[2] = 0x56;
1620                 extradata[3] = 0xE5;
1621                 extradata[4] = 0x80 | (sri<<3);
1622                 extradata_size = 5;
1623             } else
1624                 extradata_size = 2;
1625         } else if (codec_id == AV_CODEC_ID_TTA) {
1626             extradata_size = 30;
1627             extradata = av_mallocz(extradata_size + FF_INPUT_BUFFER_PADDING_SIZE);
1628             if (extradata == NULL)
1629                 return AVERROR(ENOMEM);
1630             ffio_init_context(&b, extradata, extradata_size, 1,
1631                           NULL, NULL, NULL, NULL);
1632             avio_write(&b, "TTA1", 4);
1633             avio_wl16(&b, 1);
1634             avio_wl16(&b, track->audio.channels);
1635             avio_wl16(&b, track->audio.bitdepth);
1636             avio_wl32(&b, track->audio.out_samplerate);
1637             avio_wl32(&b, matroska->ctx->duration * track->audio.out_samplerate);
1638         } else if (codec_id == AV_CODEC_ID_RV10 || codec_id == AV_CODEC_ID_RV20 ||
1639                    codec_id == AV_CODEC_ID_RV30 || codec_id == AV_CODEC_ID_RV40) {
1640             extradata_offset = 26;
1641         } else if (codec_id == AV_CODEC_ID_RA_144) {
1642             track->audio.out_samplerate = 8000;
1643             track->audio.channels = 1;
1644         } else if ((codec_id == AV_CODEC_ID_RA_288 || codec_id == AV_CODEC_ID_COOK ||
1645                     codec_id == AV_CODEC_ID_ATRAC3 || codec_id == AV_CODEC_ID_SIPR)
1646                     && track->codec_priv.data) {
1647             int flavor;
1648
1649             ffio_init_context(&b, track->codec_priv.data,track->codec_priv.size,
1650                           0, NULL, NULL, NULL, NULL);
1651             avio_skip(&b, 22);
1652             flavor                       = avio_rb16(&b);
1653             track->audio.coded_framesize = avio_rb32(&b);
1654             avio_skip(&b, 12);
1655             track->audio.sub_packet_h    = avio_rb16(&b);
1656             track->audio.frame_size      = avio_rb16(&b);
1657             track->audio.sub_packet_size = avio_rb16(&b);
1658             track->audio.buf = av_malloc(track->audio.frame_size * track->audio.sub_packet_h);
1659             if (codec_id == AV_CODEC_ID_RA_288) {
1660                 st->codec->block_align = track->audio.coded_framesize;
1661                 track->codec_priv.size = 0;
1662             } else {
1663                 if (codec_id == AV_CODEC_ID_SIPR && flavor < 4) {
1664                     const int sipr_bit_rate[4] = { 6504, 8496, 5000, 16000 };
1665                     track->audio.sub_packet_size = ff_sipr_subpk_size[flavor];
1666                     st->codec->bit_rate = sipr_bit_rate[flavor];
1667                 }
1668                 st->codec->block_align = track->audio.sub_packet_size;
1669                 extradata_offset = 78;
1670             }
1671         }
1672         track->codec_priv.size -= extradata_offset;
1673
1674         if (codec_id == AV_CODEC_ID_NONE)
1675             av_log(matroska->ctx, AV_LOG_INFO,
1676                    "Unknown/unsupported AVCodecID %s.\n", track->codec_id);
1677
1678         if (track->time_scale < 0.01)
1679             track->time_scale = 1.0;
1680         avpriv_set_pts_info(st, 64, matroska->time_scale*track->time_scale, 1000*1000*1000); /* 64 bit pts in ns */
1681
1682         st->codec->codec_id = codec_id;
1683         st->start_time = 0;
1684         if (strcmp(track->language, "und"))
1685             av_dict_set(&st->metadata, "language", track->language, 0);
1686         av_dict_set(&st->metadata, "title", track->name, 0);
1687
1688         if (track->flag_default)
1689             st->disposition |= AV_DISPOSITION_DEFAULT;
1690         if (track->flag_forced)
1691             st->disposition |= AV_DISPOSITION_FORCED;
1692
1693         if (!st->codec->extradata) {
1694             if(extradata){
1695                 st->codec->extradata = extradata;
1696                 st->codec->extradata_size = extradata_size;
1697             } else if(track->codec_priv.data && track->codec_priv.size > 0){
1698                 st->codec->extradata = av_mallocz(track->codec_priv.size +
1699                                                   FF_INPUT_BUFFER_PADDING_SIZE);
1700                 if(st->codec->extradata == NULL)
1701                     return AVERROR(ENOMEM);
1702                 st->codec->extradata_size = track->codec_priv.size;
1703                 memcpy(st->codec->extradata,
1704                        track->codec_priv.data + extradata_offset,
1705                        track->codec_priv.size);
1706             }
1707         }
1708
1709         if (track->type == MATROSKA_TRACK_TYPE_VIDEO) {
1710             MatroskaTrackPlane *planes = track->operation.combine_planes.elem;
1711
1712             st->codec->codec_type = AVMEDIA_TYPE_VIDEO;
1713             st->codec->codec_tag  = fourcc;
1714             st->codec->width  = track->video.pixel_width;
1715             st->codec->height = track->video.pixel_height;
1716             av_reduce(&st->sample_aspect_ratio.num,
1717                       &st->sample_aspect_ratio.den,
1718                       st->codec->height * track->video.display_width,
1719                       st->codec-> width * track->video.display_height,
1720                       255);
1721             st->need_parsing = AVSTREAM_PARSE_HEADERS;
1722             if (track->default_duration) {
1723                 av_reduce(&st->avg_frame_rate.num, &st->avg_frame_rate.den,
1724                           1000000000, track->default_duration, 30000);
1725 #if FF_API_R_FRAME_RATE
1726                 st->r_frame_rate = st->avg_frame_rate;
1727 #endif
1728             }
1729
1730             /* export stereo mode flag as metadata tag */
1731             if (track->video.stereo_mode && track->video.stereo_mode < MATROSKA_VIDEO_STEREO_MODE_COUNT)
1732                 av_dict_set(&st->metadata, "stereo_mode", matroska_video_stereo_mode[track->video.stereo_mode], 0);
1733
1734             /* if we have virtual track, mark the real tracks */
1735             for (j=0; j < track->operation.combine_planes.nb_elem; j++) {
1736                 char buf[32];
1737                 if (planes[j].type >= MATROSKA_VIDEO_STEREO_PLANE_COUNT)
1738                     continue;
1739                 snprintf(buf, sizeof(buf), "%s_%d",
1740                          matroska_video_stereo_plane[planes[j].type], i);
1741                 for (k=0; k < matroska->tracks.nb_elem; k++)
1742                     if (planes[j].uid == tracks[k].uid) {
1743                         av_dict_set(&s->streams[k]->metadata,
1744                                     "stereo_mode", buf, 0);
1745                         break;
1746                     }
1747             }
1748         } else if (track->type == MATROSKA_TRACK_TYPE_AUDIO) {
1749             st->codec->codec_type = AVMEDIA_TYPE_AUDIO;
1750             st->codec->sample_rate = track->audio.out_samplerate;
1751             st->codec->channels = track->audio.channels;
1752             if (st->codec->codec_id != AV_CODEC_ID_AAC)
1753             st->need_parsing = AVSTREAM_PARSE_HEADERS;
1754         } else if (track->type == MATROSKA_TRACK_TYPE_SUBTITLE) {
1755             st->codec->codec_type = AVMEDIA_TYPE_SUBTITLE;
1756             if (st->codec->codec_id == AV_CODEC_ID_SSA)
1757                 matroska->contains_ssa = 1;
1758         }
1759     }
1760
1761     attachements = attachements_list->elem;
1762     for (j=0; j<attachements_list->nb_elem; j++) {
1763         if (!(attachements[j].filename && attachements[j].mime &&
1764               attachements[j].bin.data && attachements[j].bin.size > 0)) {
1765             av_log(matroska->ctx, AV_LOG_ERROR, "incomplete attachment\n");
1766         } else {
1767             AVStream *st = avformat_new_stream(s, NULL);
1768             if (st == NULL)
1769                 break;
1770             av_dict_set(&st->metadata, "filename",attachements[j].filename, 0);
1771             av_dict_set(&st->metadata, "mimetype", attachements[j].mime, 0);
1772             st->codec->codec_id = AV_CODEC_ID_NONE;
1773             st->codec->codec_type = AVMEDIA_TYPE_ATTACHMENT;
1774             st->codec->extradata  = av_malloc(attachements[j].bin.size + FF_INPUT_BUFFER_PADDING_SIZE);
1775             if(st->codec->extradata == NULL)
1776                 break;
1777             st->codec->extradata_size = attachements[j].bin.size;
1778             memcpy(st->codec->extradata, attachements[j].bin.data, attachements[j].bin.size);
1779
1780             for (i=0; ff_mkv_mime_tags[i].id != AV_CODEC_ID_NONE; i++) {
1781                 if (!strncmp(ff_mkv_mime_tags[i].str, attachements[j].mime,
1782                              strlen(ff_mkv_mime_tags[i].str))) {
1783                     st->codec->codec_id = ff_mkv_mime_tags[i].id;
1784                     break;
1785                 }
1786             }
1787             attachements[j].stream = st;
1788         }
1789     }
1790
1791     chapters = chapters_list->elem;
1792     for (i=0; i<chapters_list->nb_elem; i++)
1793         if (chapters[i].start != AV_NOPTS_VALUE && chapters[i].uid
1794             && (max_start==0 || chapters[i].start > max_start)) {
1795             chapters[i].chapter =
1796             avpriv_new_chapter(s, chapters[i].uid, (AVRational){1, 1000000000},
1797                            chapters[i].start, chapters[i].end,
1798                            chapters[i].title);
1799             av_dict_set(&chapters[i].chapter->metadata,
1800                              "title", chapters[i].title, 0);
1801             max_start = chapters[i].start;
1802         }
1803
1804     matroska_add_index_entries(matroska);
1805
1806     matroska_convert_tags(s);
1807
1808     return 0;
1809 }
1810
1811 /*
1812  * Put one packet in an application-supplied AVPacket struct.
1813  * Returns 0 on success or -1 on failure.
1814  */
1815 static int matroska_deliver_packet(MatroskaDemuxContext *matroska,
1816                                    AVPacket *pkt)
1817 {
1818     if (matroska->num_packets > 0) {
1819         memcpy(pkt, matroska->packets[0], sizeof(AVPacket));
1820         av_free(matroska->packets[0]);
1821         if (matroska->num_packets > 1) {
1822             void *newpackets;
1823             memmove(&matroska->packets[0], &matroska->packets[1],
1824                     (matroska->num_packets - 1) * sizeof(AVPacket *));
1825             newpackets = av_realloc(matroska->packets,
1826                             (matroska->num_packets - 1) * sizeof(AVPacket *));
1827             if (newpackets)
1828                 matroska->packets = newpackets;
1829         } else {
1830             av_freep(&matroska->packets);
1831             matroska->prev_pkt = NULL;
1832         }
1833         matroska->num_packets--;
1834         return 0;
1835     }
1836
1837     return -1;
1838 }
1839
1840 /*
1841  * Free all packets in our internal queue.
1842  */
1843 static void matroska_clear_queue(MatroskaDemuxContext *matroska)
1844 {
1845     if (matroska->packets) {
1846         int n;
1847         for (n = 0; n < matroska->num_packets; n++) {
1848             av_free_packet(matroska->packets[n]);
1849             av_free(matroska->packets[n]);
1850         }
1851         av_freep(&matroska->packets);
1852         matroska->num_packets = 0;
1853     }
1854 }
1855
1856 static int matroska_parse_block(MatroskaDemuxContext *matroska, uint8_t *data,
1857                                 int size, int64_t pos, uint64_t cluster_time,
1858                                 uint64_t duration, int is_keyframe,
1859                                 int64_t cluster_pos)
1860 {
1861     uint64_t timecode = AV_NOPTS_VALUE;
1862     MatroskaTrack *track;
1863     int res = 0;
1864     AVStream *st;
1865     AVPacket *pkt;
1866     int16_t block_time;
1867     uint32_t *lace_size = NULL;
1868     int n, flags, laces = 0;
1869     uint64_t num;
1870
1871     if ((n = matroska_ebmlnum_uint(matroska, data, size, &num)) < 0) {
1872         av_log(matroska->ctx, AV_LOG_ERROR, "EBML block data error\n");
1873         return n;
1874     }
1875     data += n;
1876     size -= n;
1877
1878     track = matroska_find_track_by_num(matroska, num);
1879     if (!track || !track->stream) {
1880         av_log(matroska->ctx, AV_LOG_INFO,
1881                "Invalid stream %"PRIu64" or size %u\n", num, size);
1882         return AVERROR_INVALIDDATA;
1883     } else if (size <= 3)
1884         return 0;
1885     st = track->stream;
1886     if (st->discard >= AVDISCARD_ALL)
1887         return res;
1888     av_assert1(duration != AV_NOPTS_VALUE);
1889     if (!duration)
1890         duration = track->default_duration / matroska->time_scale;
1891
1892     block_time = AV_RB16(data);
1893     data += 2;
1894     flags = *data++;
1895     size -= 3;
1896     if (is_keyframe == -1)
1897         is_keyframe = flags & 0x80 ? AV_PKT_FLAG_KEY : 0;
1898
1899     if (cluster_time != (uint64_t)-1
1900         && (block_time >= 0 || cluster_time >= -block_time)) {
1901         timecode = cluster_time + block_time;
1902         if (track->type == MATROSKA_TRACK_TYPE_SUBTITLE
1903             && timecode < track->end_timecode)
1904             is_keyframe = 0;  /* overlapping subtitles are not key frame */
1905         if (is_keyframe)
1906             av_add_index_entry(st, cluster_pos, timecode, 0,0,AVINDEX_KEYFRAME);
1907         track->end_timecode = FFMAX(track->end_timecode, timecode+duration);
1908     }
1909
1910     if (matroska->skip_to_keyframe && track->type != MATROSKA_TRACK_TYPE_SUBTITLE) {
1911         if (timecode < matroska->skip_to_timecode)
1912             return res;
1913         if (!st->skip_to_keyframe) {
1914             av_log(matroska->ctx, AV_LOG_ERROR, "File is broken, keyframes not correctly marked!\n");
1915             matroska->skip_to_keyframe = 0;
1916         }
1917         if (is_keyframe)
1918             matroska->skip_to_keyframe = 0;
1919     }
1920
1921     switch ((flags & 0x06) >> 1) {
1922         case 0x0: /* no lacing */
1923             laces = 1;
1924             lace_size = av_mallocz(sizeof(int));
1925             lace_size[0] = size;
1926             break;
1927
1928         case 0x1: /* Xiph lacing */
1929         case 0x2: /* fixed-size lacing */
1930         case 0x3: /* EBML lacing */
1931             av_assert0(size>0); // size <=3 is checked before size-=3 above
1932             laces = (*data) + 1;
1933             data += 1;
1934             size -= 1;
1935             lace_size = av_mallocz(laces * sizeof(int));
1936
1937             switch ((flags & 0x06) >> 1) {
1938                 case 0x1: /* Xiph lacing */ {
1939                     uint8_t temp;
1940                     uint32_t total = 0;
1941                     for (n = 0; res == 0 && n < laces - 1; n++) {
1942                         while (1) {
1943                             if (size == 0) {
1944                                 res = -1;
1945                                 break;
1946                             }
1947                             temp = *data;
1948                             lace_size[n] += temp;
1949                             data += 1;
1950                             size -= 1;
1951                             if (temp != 0xff)
1952                                 break;
1953                         }
1954                         total += lace_size[n];
1955                     }
1956                     lace_size[n] = size - total;
1957                     break;
1958                 }
1959
1960                 case 0x2: /* fixed-size lacing */
1961                     for (n = 0; n < laces; n++)
1962                         lace_size[n] = size / laces;
1963                     break;
1964
1965                 case 0x3: /* EBML lacing */ {
1966                     uint32_t total;
1967                     n = matroska_ebmlnum_uint(matroska, data, size, &num);
1968                     if (n < 0) {
1969                         av_log(matroska->ctx, AV_LOG_INFO,
1970                                "EBML block data error\n");
1971                         break;
1972                     }
1973                     data += n;
1974                     size -= n;
1975                     total = lace_size[0] = num;
1976                     for (n = 1; res == 0 && n < laces - 1; n++) {
1977                         int64_t snum;
1978                         int r;
1979                         r = matroska_ebmlnum_sint(matroska, data, size, &snum);
1980                         if (r < 0) {
1981                             av_log(matroska->ctx, AV_LOG_INFO,
1982                                    "EBML block data error\n");
1983                             break;
1984                         }
1985                         data += r;
1986                         size -= r;
1987                         lace_size[n] = lace_size[n - 1] + snum;
1988                         total += lace_size[n];
1989                     }
1990                     lace_size[laces - 1] = size - total;
1991                     break;
1992                 }
1993             }
1994             break;
1995     }
1996
1997     if (res == 0) {
1998         for (n = 0; n < laces; n++) {
1999             if (lace_size[n] > size) {
2000                 av_log(matroska->ctx, AV_LOG_ERROR, "Invalid packet size\n");
2001                 break;
2002             }
2003
2004             if ((st->codec->codec_id == AV_CODEC_ID_RA_288 ||
2005                  st->codec->codec_id == AV_CODEC_ID_COOK ||
2006                  st->codec->codec_id == AV_CODEC_ID_SIPR ||
2007                  st->codec->codec_id == AV_CODEC_ID_ATRAC3) &&
2008                  st->codec->block_align && track->audio.sub_packet_size) {
2009                 int a = st->codec->block_align;
2010                 int sps = track->audio.sub_packet_size;
2011                 int cfs = track->audio.coded_framesize;
2012                 int h = track->audio.sub_packet_h;
2013                 int y = track->audio.sub_packet_cnt;
2014                 int w = track->audio.frame_size;
2015                 int x;
2016
2017                 if (!track->audio.pkt_cnt) {
2018                     if (track->audio.sub_packet_cnt == 0)
2019                         track->audio.buf_timecode = timecode;
2020                     if (st->codec->codec_id == AV_CODEC_ID_RA_288) {
2021                         if (size < cfs * h / 2) {
2022                             av_log(matroska->ctx, AV_LOG_ERROR,
2023                                    "Corrupt int4 RM-style audio packet size\n");
2024                             res = AVERROR_INVALIDDATA;
2025                             goto end;
2026                         }
2027                         for (x=0; x<h/2; x++)
2028                             memcpy(track->audio.buf+x*2*w+y*cfs,
2029                                    data+x*cfs, cfs);
2030                     } else if (st->codec->codec_id == AV_CODEC_ID_SIPR) {
2031                         if (size < w) {
2032                             av_log(matroska->ctx, AV_LOG_ERROR,
2033                                    "Corrupt sipr RM-style audio packet size\n");
2034                             res = AVERROR_INVALIDDATA;
2035                             goto end;
2036                         }
2037                         memcpy(track->audio.buf + y*w, data, w);
2038                     } else {
2039                         if (size < sps * w / sps) {
2040                             av_log(matroska->ctx, AV_LOG_ERROR,
2041                                    "Corrupt generic RM-style audio packet size\n");
2042                             res = AVERROR_INVALIDDATA;
2043                             goto end;
2044                         }
2045                         for (x=0; x<w/sps; x++)
2046                             memcpy(track->audio.buf+sps*(h*x+((h+1)/2)*(y&1)+(y>>1)), data+x*sps, sps);
2047                     }
2048
2049                     if (++track->audio.sub_packet_cnt >= h) {
2050                         if (st->codec->codec_id == AV_CODEC_ID_SIPR)
2051                             ff_rm_reorder_sipr_data(track->audio.buf, h, w);
2052                         track->audio.sub_packet_cnt = 0;
2053                         track->audio.pkt_cnt = h*w / a;
2054                     }
2055                 }
2056                 while (track->audio.pkt_cnt) {
2057                     pkt = av_mallocz(sizeof(AVPacket));
2058                     av_new_packet(pkt, a);
2059                     memcpy(pkt->data, track->audio.buf
2060                            + a * (h*w / a - track->audio.pkt_cnt--), a);
2061                     pkt->pts = track->audio.buf_timecode;
2062                     track->audio.buf_timecode = AV_NOPTS_VALUE;
2063                     pkt->pos = pos;
2064                     pkt->stream_index = st->index;
2065                     dynarray_add(&matroska->packets,&matroska->num_packets,pkt);
2066                 }
2067             } else {
2068                 MatroskaTrackEncoding *encodings = track->encodings.elem;
2069                 int offset = 0;
2070                 uint32_t pkt_size = lace_size[n];
2071                 uint8_t *pkt_data = data;
2072
2073                 if (encodings && encodings->scope & 1) {
2074                     offset = matroska_decode_buffer(&pkt_data,&pkt_size, track);
2075                     if (offset < 0)
2076                         continue;
2077                     av_assert0(offset + pkt_size >= pkt_size);
2078                 }
2079
2080                 pkt = av_mallocz(sizeof(AVPacket));
2081                 /* XXX: prevent data copy... */
2082                 if (av_new_packet(pkt, pkt_size+offset) < 0) {
2083                     av_free(pkt);
2084                     res = AVERROR(ENOMEM);
2085                     break;
2086                 }
2087                 if (offset)
2088                     memcpy (pkt->data, encodings->compression.settings.data, offset);
2089                 memcpy (pkt->data+offset, pkt_data, pkt_size);
2090
2091                 if (pkt_data != data)
2092                     av_free(pkt_data);
2093
2094                 if (n == 0)
2095                     pkt->flags = is_keyframe;
2096                 pkt->stream_index = st->index;
2097
2098                 if (track->ms_compat)
2099                     pkt->dts = timecode;
2100                 else
2101                     pkt->pts = timecode;
2102                 pkt->pos = pos;
2103                 if (st->codec->codec_id == AV_CODEC_ID_TEXT)
2104                     pkt->convergence_duration = duration;
2105                 else if (track->type != MATROSKA_TRACK_TYPE_SUBTITLE)
2106                     pkt->duration = duration;
2107
2108                 if (st->codec->codec_id == AV_CODEC_ID_SSA)
2109                     matroska_fix_ass_packet(matroska, pkt, duration);
2110
2111                 if (matroska->prev_pkt &&
2112                     timecode != AV_NOPTS_VALUE &&
2113                     matroska->prev_pkt->pts == timecode &&
2114                     matroska->prev_pkt->stream_index == st->index &&
2115                     st->codec->codec_id == AV_CODEC_ID_SSA)
2116                     matroska_merge_packets(matroska->prev_pkt, pkt);
2117                 else {
2118                     dynarray_add(&matroska->packets,&matroska->num_packets,pkt);
2119                     matroska->prev_pkt = pkt;
2120                 }
2121             }
2122
2123             if (timecode != AV_NOPTS_VALUE)
2124                 timecode = duration ? timecode + duration : AV_NOPTS_VALUE;
2125             data += lace_size[n];
2126             size -= lace_size[n];
2127         }
2128     }
2129
2130 end:
2131     av_free(lace_size);
2132     return res;
2133 }
2134
2135 static int matroska_parse_cluster_incremental(MatroskaDemuxContext *matroska)
2136 {
2137     EbmlList *blocks_list;
2138     MatroskaBlock *blocks;
2139     int i, res;
2140     res = ebml_parse(matroska,
2141                      matroska_cluster_incremental_parsing,
2142                      &matroska->current_cluster);
2143     if (res == 1) {
2144         /* New Cluster */
2145         if (matroska->current_cluster_pos)
2146             ebml_level_end(matroska);
2147         ebml_free(matroska_cluster, &matroska->current_cluster);
2148         memset(&matroska->current_cluster, 0, sizeof(MatroskaCluster));
2149         matroska->current_cluster_num_blocks = 0;
2150         matroska->current_cluster_pos = avio_tell(matroska->ctx->pb);
2151         matroska->prev_pkt = NULL;
2152         /* sizeof the ID which was already read */
2153         if (matroska->current_id)
2154             matroska->current_cluster_pos -= 4;
2155         res = ebml_parse(matroska,
2156                          matroska_clusters_incremental,
2157                          &matroska->current_cluster);
2158         /* Try parsing the block again. */
2159         if (res == 1)
2160             res = ebml_parse(matroska,
2161                              matroska_cluster_incremental_parsing,
2162                              &matroska->current_cluster);
2163     }
2164
2165     if (!res &&
2166         matroska->current_cluster_num_blocks <
2167             matroska->current_cluster.blocks.nb_elem) {
2168         blocks_list = &matroska->current_cluster.blocks;
2169         blocks = blocks_list->elem;
2170
2171         matroska->current_cluster_num_blocks = blocks_list->nb_elem;
2172         i = blocks_list->nb_elem - 1;
2173         if (blocks[i].bin.size > 0 && blocks[i].bin.data) {
2174             int is_keyframe = blocks[i].non_simple ? !blocks[i].reference : -1;
2175             if (!blocks[i].non_simple)
2176                 blocks[i].duration = 0;
2177             res = matroska_parse_block(matroska,
2178                                        blocks[i].bin.data, blocks[i].bin.size,
2179                                        blocks[i].bin.pos,
2180                                        matroska->current_cluster.timecode,
2181                                        blocks[i].duration, is_keyframe,
2182                                        matroska->current_cluster_pos);
2183         }
2184     }
2185
2186     if (res < 0)  matroska->done = 1;
2187     return res;
2188 }
2189
2190 static int matroska_parse_cluster(MatroskaDemuxContext *matroska)
2191 {
2192     MatroskaCluster cluster = { 0 };
2193     EbmlList *blocks_list;
2194     MatroskaBlock *blocks;
2195     int i, res;
2196     int64_t pos;
2197     if (!matroska->contains_ssa)
2198         return matroska_parse_cluster_incremental(matroska);
2199     pos = avio_tell(matroska->ctx->pb);
2200     matroska->prev_pkt = NULL;
2201     if (matroska->current_id)
2202         pos -= 4;  /* sizeof the ID which was already read */
2203     res = ebml_parse(matroska, matroska_clusters, &cluster);
2204     blocks_list = &cluster.blocks;
2205     blocks = blocks_list->elem;
2206     for (i=0; i<blocks_list->nb_elem; i++)
2207         if (blocks[i].bin.size > 0 && blocks[i].bin.data) {
2208             int is_keyframe = blocks[i].non_simple ? !blocks[i].reference : -1;
2209             res=matroska_parse_block(matroska,
2210                                      blocks[i].bin.data, blocks[i].bin.size,
2211                                      blocks[i].bin.pos,  cluster.timecode,
2212                                      blocks[i].duration, is_keyframe,
2213                                      pos);
2214         }
2215     ebml_free(matroska_cluster, &cluster);
2216     return res;
2217 }
2218
2219 static int matroska_read_packet(AVFormatContext *s, AVPacket *pkt)
2220 {
2221     MatroskaDemuxContext *matroska = s->priv_data;
2222
2223     while (matroska_deliver_packet(matroska, pkt)) {
2224         int64_t pos = avio_tell(matroska->ctx->pb);
2225         if (matroska->done)
2226             return AVERROR_EOF;
2227         if (matroska_parse_cluster(matroska) < 0)
2228             matroska_resync(matroska, pos);
2229     }
2230
2231     return 0;
2232 }
2233
2234 static int matroska_read_seek(AVFormatContext *s, int stream_index,
2235                               int64_t timestamp, int flags)
2236 {
2237     MatroskaDemuxContext *matroska = s->priv_data;
2238     MatroskaTrack *tracks = matroska->tracks.elem;
2239     AVStream *st = s->streams[stream_index];
2240     int i, index, index_sub, index_min;
2241
2242     /* Parse the CUES now since we need the index data to seek. */
2243     if (matroska->cues_parsing_deferred > 0) {
2244         matroska->cues_parsing_deferred = 0;
2245         matroska_parse_cues(matroska);
2246     }
2247
2248     if (!st->nb_index_entries)
2249         goto err;
2250     timestamp = FFMAX(timestamp, st->index_entries[0].timestamp);
2251
2252     if ((index = av_index_search_timestamp(st, timestamp, flags)) < 0) {
2253         avio_seek(s->pb, st->index_entries[st->nb_index_entries-1].pos, SEEK_SET);
2254         matroska->current_id = 0;
2255         while ((index = av_index_search_timestamp(st, timestamp, flags)) < 0) {
2256             matroska->prev_pkt = NULL;
2257             matroska_clear_queue(matroska);
2258             if (matroska_parse_cluster(matroska) < 0)
2259                 break;
2260         }
2261     }
2262
2263     matroska_clear_queue(matroska);
2264     if (index < 0 || (matroska->cues_parsing_deferred < 0 && index == st->nb_index_entries - 1))
2265         goto err;
2266
2267     index_min = index;
2268     for (i=0; i < matroska->tracks.nb_elem; i++) {
2269         tracks[i].audio.pkt_cnt = 0;
2270         tracks[i].audio.sub_packet_cnt = 0;
2271         tracks[i].audio.buf_timecode = AV_NOPTS_VALUE;
2272         tracks[i].end_timecode = 0;
2273         if (tracks[i].type == MATROSKA_TRACK_TYPE_SUBTITLE
2274             && !tracks[i].stream->discard != AVDISCARD_ALL) {
2275             index_sub = av_index_search_timestamp(tracks[i].stream, st->index_entries[index].timestamp, AVSEEK_FLAG_BACKWARD);
2276             if (index_sub >= 0
2277                 && st->index_entries[index_sub].pos < st->index_entries[index_min].pos
2278                 && st->index_entries[index].timestamp - st->index_entries[index_sub].timestamp < 30000000000/matroska->time_scale)
2279                 index_min = index_sub;
2280         }
2281     }
2282
2283     avio_seek(s->pb, st->index_entries[index_min].pos, SEEK_SET);
2284     matroska->current_id = 0;
2285     st->skip_to_keyframe =
2286     matroska->skip_to_keyframe = !(flags & AVSEEK_FLAG_ANY);
2287     matroska->skip_to_timecode = st->index_entries[index].timestamp;
2288     matroska->done = 0;
2289     matroska->num_levels = 0;
2290     ff_update_cur_dts(s, st, st->index_entries[index].timestamp);
2291     return 0;
2292 err:
2293     // slightly hackish but allows proper fallback to
2294     // the generic seeking code.
2295     matroska_clear_queue(matroska);
2296     matroska->current_id = 0;
2297     st->skip_to_keyframe =
2298     matroska->skip_to_keyframe = 0;
2299     matroska->done = 0;
2300     matroska->num_levels = 0;
2301     return -1;
2302 }
2303
2304 static int matroska_read_close(AVFormatContext *s)
2305 {
2306     MatroskaDemuxContext *matroska = s->priv_data;
2307     MatroskaTrack *tracks = matroska->tracks.elem;
2308     int n;
2309
2310     matroska_clear_queue(matroska);
2311
2312     for (n=0; n < matroska->tracks.nb_elem; n++)
2313         if (tracks[n].type == MATROSKA_TRACK_TYPE_AUDIO)
2314             av_free(tracks[n].audio.buf);
2315     ebml_free(matroska_cluster, &matroska->current_cluster);
2316     ebml_free(matroska_segment, matroska);
2317
2318     return 0;
2319 }
2320
2321 AVInputFormat ff_matroska_demuxer = {
2322     .name           = "matroska,webm",
2323     .long_name      = NULL_IF_CONFIG_SMALL("Matroska / WebM"),
2324     .priv_data_size = sizeof(MatroskaDemuxContext),
2325     .read_probe     = matroska_probe,
2326     .read_header    = matroska_read_header,
2327     .read_packet    = matroska_read_packet,
2328     .read_close     = matroska_read_close,
2329     .read_seek      = matroska_read_seek,
2330 };