libavformat/matroskadec.c

   1 /*
   2  * Matroska file demuxer
   3  * Copyright (c) 2003-2008 The FFmpeg Project
   4  *
   5  * This file is part of FFmpeg.
   6  *
   7  * FFmpeg is free software; you can redistribute it and/or
   8  * modify it under the terms of the GNU Lesser General Public
   9  * License as published by the Free Software Foundation; either
  10  * version 2.1 of the License, or (at your option) any later version.
  11  *
  12  * FFmpeg is distributed in the hope that it will be useful,
  13  * but WITHOUT ANY WARRANTY; without even the implied warranty of
  14  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
  15  * Lesser General Public License for more details.
  16  *
  17  * You should have received a copy of the GNU Lesser General Public
  18  * License along with FFmpeg; if not, write to the Free Software
  19  * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA
  20  */
  21
  22 /**
  23  * @file matroskadec.c
  24  * Matroska file demuxer
  25  * by Ronald Bultje <rbultje@ronald.bitfreak.net>
  26  * with a little help from Moritz Bunkus <moritz@bunkus.org>
  27  * totally reworked by Aurelien Jacobs <aurel@gnuage.org>
  28  * Specs available on the Matroska project page: http://www.matroska.org/.
  29  */
  30
  31 #include <stdio.h>
  32 #include "avformat.h"
  33 /* For codec_get_id(). */
  34 #include "riff.h"
  35 #include "isom.h"
  36 #include "matroska.h"
  37 #include "libavcodec/mpeg4audio.h"
  38 #include "libavutil/intfloat_readwrite.h"
  39 #include "libavutil/avstring.h"
  40 #include "libavutil/lzo.h"
  41 #ifdef CONFIG_ZLIB
  42 #include <zlib.h>
  43 #endif
  44 #ifdef CONFIG_BZLIB
  45 #include <bzlib.h>
  46 #endif
  47
  48 typedef enum {
  49     EBML_NONE,
  50     EBML_UINT,
  51     EBML_FLOAT,
  52     EBML_STR,
  53     EBML_UTF8,
  54     EBML_BIN,
  55     EBML_NEST,
  56     EBML_PASS,
  57     EBML_STOP,
  58 } EbmlType;
  59
  60 typedef const struct EbmlSyntax {
  61     uint32_t id;
  62     EbmlType type;
  63     int list_elem_size;
  64     int data_offset;
  65     union {
  66         uint64_t    u;
  67         double      f;
  68         const char *s;
  69         const struct EbmlSyntax *n;
  70     } def;
  71 } EbmlSyntax;
  72
  73 typedef struct {
  74     int nb_elem;
  75     void *elem;
  76 } EbmlList;
  77
  78 typedef struct {
  79     int      size;
  80     uint8_t *data;
  81     int64_t  pos;
  82 } EbmlBin;
  83
  84 typedef struct {
  85     uint64_t version;
  86     uint64_t max_size;
  87     uint64_t id_length;
  88     char    *doctype;
  89     uint64_t doctype_version;
  90 } Ebml;
  91
  92 typedef struct {
  93     uint64_t algo;
  94     EbmlBin  settings;
  95 } MatroskaTrackCompression;
  96
  97 typedef struct {
  98     uint64_t scope;
  99     uint64_t type;
 100     MatroskaTrackCompression compression;
 101 } MatroskaTrackEncoding;
 102
 103 typedef struct {
 104     double   frame_rate;
 105     uint64_t display_width;
 106     uint64_t display_height;
 107     uint64_t pixel_width;
 108     uint64_t pixel_height;
 109     uint64_t fourcc;
 110 } MatroskaTrackVideo;
 111
 112 typedef struct {
 113     double   samplerate;
 114     double   out_samplerate;
 115     uint64_t bitdepth;
 116     uint64_t channels;
 117
 118     /* real audio header (extracted from extradata) */
 119     int      coded_framesize;
 120     int      sub_packet_h;
 121     int      frame_size;
 122     int      sub_packet_size;
 123     int      sub_packet_cnt;
 124     int      pkt_cnt;
 125     uint8_t *buf;
 126 } MatroskaTrackAudio;
 127
 128 typedef struct {
 129     uint64_t num;
 130     uint64_t type;
 131     char    *codec_id;
 132     EbmlBin  codec_priv;
 133     char    *language;
 134     double time_scale;
 135     uint64_t default_duration;
 136     uint64_t flag_default;
 137     MatroskaTrackVideo video;
 138     MatroskaTrackAudio audio;
 139     EbmlList encodings;
 140
 141     AVStream *stream;
 142     int64_t end_timecode;
 143 } MatroskaTrack;
 144
 145 typedef struct {
 146     char *filename;
 147     char *mime;
 148     EbmlBin bin;
 149 } MatroskaAttachement;
 150
 151 typedef struct {
 152     uint64_t start;
 153     uint64_t end;
 154     uint64_t uid;
 155     char    *title;
 156 } MatroskaChapter;
 157
 158 typedef struct {
 159     uint64_t track;
 160     uint64_t pos;
 161 } MatroskaIndexPos;
 162
 163 typedef struct {
 164     uint64_t time;
 165     EbmlList pos;
 166 } MatroskaIndex;
 167
 168 typedef struct {
 169     char *name;
 170     char *string;
 171     EbmlList sub;
 172 } MatroskaTag;
 173
 174 typedef struct {
 175     uint64_t id;
 176     uint64_t pos;
 177 } MatroskaSeekhead;
 178
 179 typedef struct {
 180     uint64_t start;
 181     uint64_t length;
 182 } MatroskaLevel;
 183
 184 typedef struct {
 185     AVFormatContext *ctx;
 186
 187     /* EBML stuff */
 188     int num_levels;
 189     MatroskaLevel levels[EBML_MAX_DEPTH];
 190     int level_up;
 191
 192     uint64_t time_scale;
 193     double   duration;
 194     char    *title;
 195     EbmlList tracks;
 196     EbmlList attachments;
 197     EbmlList chapters;
 198     EbmlList index;
 199     EbmlList tags;
 200     EbmlList seekhead;
 201
 202     /* byte position of the segment inside the stream */
 203     int64_t segment_start;
 204
 205     /* the packet queue */
 206     AVPacket **packets;
 207     int num_packets;
 208     AVPacket *prev_pkt;
 209
 210     int done;
 211     int has_cluster_id;
 212
 213     /* What to skip before effectively reading a packet. */
 214     int skip_to_keyframe;
 215     uint64_t skip_to_timecode;
 216 } MatroskaDemuxContext;
 217
 218 typedef struct {
 219     uint64_t duration;
 220     int64_t  reference;
 221     EbmlBin  bin;
 222 } MatroskaBlock;
 223
 224 typedef struct {
 225     uint64_t timecode;
 226     EbmlList blocks;
 227 } MatroskaCluster;
 228
 229 #define ARRAY_SIZE(x)  (sizeof(x)/sizeof(*x))
 230
 231 static EbmlSyntax ebml_header[] = {
 232     { EBML_ID_EBMLREADVERSION,        EBML_UINT, 0, offsetof(Ebml,version), {.u=EBML_VERSION} },
 233     { EBML_ID_EBMLMAXSIZELENGTH,      EBML_UINT, 0, offsetof(Ebml,max_size), {.u=8} },
 234     { EBML_ID_EBMLMAXIDLENGTH,        EBML_UINT, 0, offsetof(Ebml,id_length), {.u=4} },
 235     { EBML_ID_DOCTYPE,                EBML_STR,  0, offsetof(Ebml,doctype), {.s="(none)"} },
 236     { EBML_ID_DOCTYPEREADVERSION,     EBML_UINT, 0, offsetof(Ebml,doctype_version), {.u=1} },
 237     { EBML_ID_EBMLVERSION,            EBML_NONE },
 238     { EBML_ID_DOCTYPEVERSION,         EBML_NONE },
 239     { 0 }
 240 };
 241
 242 static EbmlSyntax ebml_syntax[] = {
 243     { EBML_ID_HEADER,                 EBML_NEST, 0, 0, {.n=ebml_header} },
 244     { 0 }
 245 };
 246
 247 static EbmlSyntax matroska_info[] = {
 248     { MATROSKA_ID_TIMECODESCALE,      EBML_UINT,  0, offsetof(MatroskaDemuxContext,time_scale), {.u=1000000} },
 249     { MATROSKA_ID_DURATION,           EBML_FLOAT, 0, offsetof(MatroskaDemuxContext,duration) },
 250     { MATROSKA_ID_TITLE,              EBML_UTF8,  0, offsetof(MatroskaDemuxContext,title) },
 251     { MATROSKA_ID_WRITINGAPP,         EBML_NONE },
 252     { MATROSKA_ID_MUXINGAPP,          EBML_NONE },
 253     { MATROSKA_ID_DATEUTC,            EBML_NONE },
 254     { MATROSKA_ID_SEGMENTUID,         EBML_NONE },
 255     { 0 }
 256 };
 257
 258 static EbmlSyntax matroska_track_video[] = {
 259     { MATROSKA_ID_VIDEOFRAMERATE,     EBML_FLOAT,0, offsetof(MatroskaTrackVideo,frame_rate) },
 260     { MATROSKA_ID_VIDEODISPLAYWIDTH,  EBML_UINT, 0, offsetof(MatroskaTrackVideo,display_width) },
 261     { MATROSKA_ID_VIDEODISPLAYHEIGHT, EBML_UINT, 0, offsetof(MatroskaTrackVideo,display_height) },
 262     { MATROSKA_ID_VIDEOPIXELWIDTH,    EBML_UINT, 0, offsetof(MatroskaTrackVideo,pixel_width) },
 263     { MATROSKA_ID_VIDEOPIXELHEIGHT,   EBML_UINT, 0, offsetof(MatroskaTrackVideo,pixel_height) },
 264     { MATROSKA_ID_VIDEOCOLORSPACE,    EBML_UINT, 0, offsetof(MatroskaTrackVideo,fourcc) },
 265     { MATROSKA_ID_VIDEOPIXELCROPB,    EBML_NONE },
 266     { MATROSKA_ID_VIDEOPIXELCROPT,    EBML_NONE },
 267     { MATROSKA_ID_VIDEOPIXELCROPL,    EBML_NONE },
 268     { MATROSKA_ID_VIDEOPIXELCROPR,    EBML_NONE },
 269     { MATROSKA_ID_VIDEODISPLAYUNIT,   EBML_NONE },
 270     { MATROSKA_ID_VIDEOFLAGINTERLACED,EBML_NONE },
 271     { MATROSKA_ID_VIDEOSTEREOMODE,    EBML_NONE },
 272     { MATROSKA_ID_VIDEOASPECTRATIO,   EBML_NONE },
 273     { 0 }
 274 };
 275
 276 static EbmlSyntax matroska_track_audio[] = {
 277     { MATROSKA_ID_AUDIOSAMPLINGFREQ,  EBML_FLOAT,0, offsetof(MatroskaTrackAudio,samplerate), {.f=8000.0} },
 278     { MATROSKA_ID_AUDIOOUTSAMPLINGFREQ,EBML_FLOAT,0,offsetof(MatroskaTrackAudio,out_samplerate) },
 279     { MATROSKA_ID_AUDIOBITDEPTH,      EBML_UINT, 0, offsetof(MatroskaTrackAudio,bitdepth) },
 280     { MATROSKA_ID_AUDIOCHANNELS,      EBML_UINT, 0, offsetof(MatroskaTrackAudio,channels), {.u=1} },
 281     { 0 }
 282 };
 283
 284 static EbmlSyntax matroska_track_encoding_compression[] = {
 285     { MATROSKA_ID_ENCODINGCOMPALGO,   EBML_UINT, 0, offsetof(MatroskaTrackCompression,algo), {.u=0} },
 286     { MATROSKA_ID_ENCODINGCOMPSETTINGS,EBML_BIN, 0, offsetof(MatroskaTrackCompression,settings) },
 287     { 0 }
 288 };
 289
 290 static EbmlSyntax matroska_track_encoding[] = {
 291     { MATROSKA_ID_ENCODINGSCOPE,      EBML_UINT, 0, offsetof(MatroskaTrackEncoding,scope), {.u=1} },
 292     { MATROSKA_ID_ENCODINGTYPE,       EBML_UINT, 0, offsetof(MatroskaTrackEncoding,type), {.u=0} },
 293     { MATROSKA_ID_ENCODINGCOMPRESSION,EBML_NEST, 0, offsetof(MatroskaTrackEncoding,compression), {.n=matroska_track_encoding_compression} },
 294     { MATROSKA_ID_ENCODINGORDER,      EBML_NONE },
 295     { 0 }
 296 };
 297
 298 static EbmlSyntax matroska_track_encodings[] = {
 299     { MATROSKA_ID_TRACKCONTENTENCODING, EBML_NEST, sizeof(MatroskaTrackEncoding), offsetof(MatroskaTrack,encodings), {.n=matroska_track_encoding} },
 300     { 0 }
 301 };
 302
 303 static EbmlSyntax matroska_track[] = {
 304     { MATROSKA_ID_TRACKNUMBER,          EBML_UINT, 0, offsetof(MatroskaTrack,num) },
 305     { MATROSKA_ID_TRACKTYPE,            EBML_UINT, 0, offsetof(MatroskaTrack,type) },
 306     { MATROSKA_ID_CODECID,              EBML_STR,  0, offsetof(MatroskaTrack,codec_id) },
 307     { MATROSKA_ID_CODECPRIVATE,         EBML_BIN,  0, offsetof(MatroskaTrack,codec_priv) },
 308     { MATROSKA_ID_TRACKLANGUAGE,        EBML_UTF8, 0, offsetof(MatroskaTrack,language), {.s="eng"} },
 309     { MATROSKA_ID_TRACKDEFAULTDURATION, EBML_UINT, 0, offsetof(MatroskaTrack,default_duration) },
 310     { MATROSKA_ID_TRACKTIMECODESCALE,   EBML_FLOAT,0, offsetof(MatroskaTrack,time_scale), {.f=1.0} },
 311     { MATROSKA_ID_TRACKFLAGDEFAULT,     EBML_UINT, 0, offsetof(MatroskaTrack,flag_default), {.u=1} },
 312     { MATROSKA_ID_TRACKVIDEO,           EBML_NEST, 0, offsetof(MatroskaTrack,video), {.n=matroska_track_video} },
 313     { MATROSKA_ID_TRACKAUDIO,           EBML_NEST, 0, offsetof(MatroskaTrack,audio), {.n=matroska_track_audio} },
 314     { MATROSKA_ID_TRACKCONTENTENCODINGS,EBML_NEST, 0, 0, {.n=matroska_track_encodings} },
 315     { MATROSKA_ID_TRACKUID,             EBML_NONE },
 316     { MATROSKA_ID_TRACKNAME,            EBML_NONE },
 317     { MATROSKA_ID_TRACKFLAGENABLED,     EBML_NONE },
 318     { MATROSKA_ID_TRACKFLAGFORCED,      EBML_NONE },
 319     { MATROSKA_ID_TRACKFLAGLACING,      EBML_NONE },
 320     { MATROSKA_ID_CODECNAME,            EBML_NONE },
 321     { MATROSKA_ID_CODECDECODEALL,       EBML_NONE },
 322     { MATROSKA_ID_CODECINFOURL,         EBML_NONE },
 323     { MATROSKA_ID_CODECDOWNLOADURL,     EBML_NONE },
 324     { MATROSKA_ID_TRACKMINCACHE,        EBML_NONE },
 325     { MATROSKA_ID_TRACKMAXCACHE,        EBML_NONE },
 326     { MATROSKA_ID_TRACKMAXBLKADDID,     EBML_NONE },
 327     { 0 }
 328 };
 329
 330 static EbmlSyntax matroska_tracks[] = {
 331     { MATROSKA_ID_TRACKENTRY,         EBML_NEST, sizeof(MatroskaTrack), offsetof(MatroskaDemuxContext,tracks), {.n=matroska_track} },
 332     { 0 }
 333 };
 334
 335 static EbmlSyntax matroska_attachment[] = {
 336     { MATROSKA_ID_FILENAME,           EBML_UTF8, 0, offsetof(MatroskaAttachement,filename) },
 337     { MATROSKA_ID_FILEMIMETYPE,       EBML_STR,  0, offsetof(MatroskaAttachement,mime) },
 338     { MATROSKA_ID_FILEDATA,           EBML_BIN,  0, offsetof(MatroskaAttachement,bin) },
 339     { MATROSKA_ID_FILEDESC,           EBML_NONE },
 340     { MATROSKA_ID_FILEUID,            EBML_NONE },
 341     { 0 }
 342 };
 343
 344 static EbmlSyntax matroska_attachments[] = {
 345     { MATROSKA_ID_ATTACHEDFILE,       EBML_NEST, sizeof(MatroskaAttachement), offsetof(MatroskaDemuxContext,attachments), {.n=matroska_attachment} },
 346     { 0 }
 347 };
 348
 349 static EbmlSyntax matroska_chapter_display[] = {
 350     { MATROSKA_ID_CHAPSTRING,         EBML_UTF8, 0, offsetof(MatroskaChapter,title) },
 351     { MATROSKA_ID_CHAPLANG,           EBML_NONE },
 352     { 0 }
 353 };
 354
 355 static EbmlSyntax matroska_chapter_entry[] = {
 356     { MATROSKA_ID_CHAPTERTIMESTART,   EBML_UINT, 0, offsetof(MatroskaChapter,start), {.u=AV_NOPTS_VALUE} },
 357     { MATROSKA_ID_CHAPTERTIMEEND,     EBML_UINT, 0, offsetof(MatroskaChapter,end), {.u=AV_NOPTS_VALUE} },
 358     { MATROSKA_ID_CHAPTERUID,         EBML_UINT, 0, offsetof(MatroskaChapter,uid) },
 359     { MATROSKA_ID_CHAPTERDISPLAY,     EBML_NEST, 0, 0, {.n=matroska_chapter_display} },
 360     { MATROSKA_ID_CHAPTERFLAGHIDDEN,  EBML_NONE },
 361     { MATROSKA_ID_CHAPTERFLAGENABLED, EBML_NONE },
 362     { MATROSKA_ID_CHAPTERPHYSEQUIV,   EBML_NONE },
 363     { MATROSKA_ID_CHAPTERATOM,        EBML_NONE },
 364     { 0 }
 365 };
 366
 367 static EbmlSyntax matroska_chapter[] = {
 368     { MATROSKA_ID_CHAPTERATOM,        EBML_NEST, sizeof(MatroskaChapter), offsetof(MatroskaDemuxContext,chapters), {.n=matroska_chapter_entry} },
 369     { MATROSKA_ID_EDITIONUID,         EBML_NONE },
 370     { MATROSKA_ID_EDITIONFLAGHIDDEN,  EBML_NONE },
 371     { MATROSKA_ID_EDITIONFLAGDEFAULT, EBML_NONE },
 372     { MATROSKA_ID_EDITIONFLAGORDERED, EBML_NONE },
 373     { 0 }
 374 };
 375
 376 static EbmlSyntax matroska_chapters[] = {
 377     { MATROSKA_ID_EDITIONENTRY,       EBML_NEST, 0, 0, {.n=matroska_chapter} },
 378     { 0 }
 379 };
 380
 381 static EbmlSyntax matroska_index_pos[] = {
 382     { MATROSKA_ID_CUETRACK,           EBML_UINT, 0, offsetof(MatroskaIndexPos,track) },
 383     { MATROSKA_ID_CUECLUSTERPOSITION, EBML_UINT, 0, offsetof(MatroskaIndexPos,pos)   },
 384     { MATROSKA_ID_CUEBLOCKNUMBER,     EBML_NONE },
 385     { 0 }
 386 };
 387
 388 static EbmlSyntax matroska_index_entry[] = {
 389     { MATROSKA_ID_CUETIME,            EBML_UINT, 0, offsetof(MatroskaIndex,time) },
 390     { MATROSKA_ID_CUETRACKPOSITION,   EBML_NEST, sizeof(MatroskaIndexPos), offsetof(MatroskaIndex,pos), {.n=matroska_index_pos} },
 391     { 0 }
 392 };
 393
 394 static EbmlSyntax matroska_index[] = {
 395     { MATROSKA_ID_POINTENTRY,         EBML_NEST, sizeof(MatroskaIndex), offsetof(MatroskaDemuxContext,index), {.n=matroska_index_entry} },
 396     { 0 }
 397 };
 398
 399 static EbmlSyntax matroska_simpletag[] = {
 400     { MATROSKA_ID_TAGNAME,            EBML_UTF8, 0, offsetof(MatroskaTag,name) },
 401     { MATROSKA_ID_TAGSTRING,          EBML_UTF8, 0, offsetof(MatroskaTag,string) },
 402     { MATROSKA_ID_SIMPLETAG,          EBML_NEST, sizeof(MatroskaTag), offsetof(MatroskaTag,sub), {.n=matroska_simpletag} },
 403     { MATROSKA_ID_TAGLANG,            EBML_NONE },
 404     { MATROSKA_ID_TAGDEFAULT,         EBML_NONE },
 405     { 0 }
 406 };
 407
 408 static EbmlSyntax matroska_tag[] = {
 409     { MATROSKA_ID_SIMPLETAG,          EBML_NEST, sizeof(MatroskaTag), 0, {.n=matroska_simpletag} },
 410     { MATROSKA_ID_TAGTARGETS,         EBML_NONE },
 411     { 0 }
 412 };
 413
 414 static EbmlSyntax matroska_tags[] = {
 415     { MATROSKA_ID_TAG,                EBML_NEST, 0, offsetof(MatroskaDemuxContext,tags), {.n=matroska_tag} },
 416     { 0 }
 417 };
 418
 419 static EbmlSyntax matroska_seekhead_entry[] = {
 420     { MATROSKA_ID_SEEKID,             EBML_UINT, 0, offsetof(MatroskaSeekhead,id) },
 421     { MATROSKA_ID_SEEKPOSITION,       EBML_UINT, 0, offsetof(MatroskaSeekhead,pos), {.u=-1} },
 422     { 0 }
 423 };
 424
 425 static EbmlSyntax matroska_seekhead[] = {
 426     { MATROSKA_ID_SEEKENTRY,          EBML_NEST, sizeof(MatroskaSeekhead), offsetof(MatroskaDemuxContext,seekhead), {.n=matroska_seekhead_entry} },
 427     { 0 }
 428 };
 429
 430 static EbmlSyntax matroska_segment[] = {
 431     { MATROSKA_ID_INFO,           EBML_NEST, 0, 0, {.n=matroska_info       } },
 432     { MATROSKA_ID_TRACKS,         EBML_NEST, 0, 0, {.n=matroska_tracks     } },
 433     { MATROSKA_ID_ATTACHMENTS,    EBML_NEST, 0, 0, {.n=matroska_attachments} },
 434     { MATROSKA_ID_CHAPTERS,       EBML_NEST, 0, 0, {.n=matroska_chapters   } },
 435     { MATROSKA_ID_CUES,           EBML_NEST, 0, 0, {.n=matroska_index      } },
 436     { MATROSKA_ID_TAGS,           EBML_NEST, 0, 0, {.n=matroska_tags       } },
 437     { MATROSKA_ID_SEEKHEAD,       EBML_NEST, 0, 0, {.n=matroska_seekhead   } },
 438     { MATROSKA_ID_CLUSTER,        EBML_STOP, 0, offsetof(MatroskaDemuxContext,has_cluster_id) },
 439     { 0 }
 440 };
 441
 442 static EbmlSyntax matroska_segments[] = {
 443     { MATROSKA_ID_SEGMENT,        EBML_NEST, 0, 0, {.n=matroska_segment    } },
 444     { 0 }
 445 };
 446
 447 static EbmlSyntax matroska_blockgroup[] = {
 448     { MATROSKA_ID_BLOCK,          EBML_BIN,  0, offsetof(MatroskaBlock,bin) },
 449     { MATROSKA_ID_SIMPLEBLOCK,    EBML_BIN,  0, offsetof(MatroskaBlock,bin) },
 450     { MATROSKA_ID_BLOCKDURATION,  EBML_UINT, 0, offsetof(MatroskaBlock,duration), {.u=AV_NOPTS_VALUE} },
 451     { MATROSKA_ID_BLOCKREFERENCE, EBML_UINT, 0, offsetof(MatroskaBlock,reference) },
 452     { 0 }
 453 };
 454
 455 static EbmlSyntax matroska_cluster[] = {
 456     { MATROSKA_ID_CLUSTERTIMECODE,EBML_UINT,0, offsetof(MatroskaCluster,timecode) },
 457     { MATROSKA_ID_BLOCKGROUP,     EBML_NEST, sizeof(MatroskaBlock), offsetof(MatroskaCluster,blocks), {.n=matroska_blockgroup} },
 458     { MATROSKA_ID_SIMPLEBLOCK,    EBML_PASS, sizeof(MatroskaBlock), offsetof(MatroskaCluster,blocks), {.n=matroska_blockgroup} },
 459     { MATROSKA_ID_CLUSTERPOSITION,EBML_NONE },
 460     { MATROSKA_ID_CLUSTERPREVSIZE,EBML_NONE },
 461     { 0 }
 462 };
 463
 464 static EbmlSyntax matroska_clusters[] = {
 465     { MATROSKA_ID_CLUSTER,        EBML_NEST, 0, 0, {.n=matroska_cluster} },
 466     { MATROSKA_ID_INFO,           EBML_NONE },
 467     { MATROSKA_ID_CUES,           EBML_NONE },
 468     { MATROSKA_ID_TAGS,           EBML_NONE },
 469     { MATROSKA_ID_SEEKHEAD,       EBML_NONE },
 470     { 0 }
 471 };
 472
 473 #define SIZE_OFF(x) sizeof(((AVFormatContext*)0)->x),offsetof(AVFormatContext,x)
 474 const struct {
 475     const char name[16];
 476     int   size;
 477     int   offset;
 478 } metadata[] = {
 479     { "TITLE",           SIZE_OFF(title)      },
 480     { "ARTIST",          SIZE_OFF(author)     },
 481     { "WRITTEN_BY",      SIZE_OFF(author)     },
 482     { "LEAD_PERFORMER",  SIZE_OFF(author)     },
 483     { "COPYRIGHT",       SIZE_OFF(copyright)  },
 484     { "COMMENT",         SIZE_OFF(comment)    },
 485     { "ALBUM",           SIZE_OFF(album)      },
 486     { "DATE_WRITTEN",    SIZE_OFF(year)       },
 487     { "DATE_RELEASED",   SIZE_OFF(year)       },
 488     { "PART_NUMBER",     SIZE_OFF(track)      },
 489     { "GENRE",           SIZE_OFF(genre)      },
 490 };
 491
 492 /*
 493  * Return: Whether we reached the end of a level in the hierarchy or not.
 494  */
 495 static int ebml_level_end(MatroskaDemuxContext *matroska)
 496 {
 497     ByteIOContext *pb = matroska->ctx->pb;
 498     int64_t pos = url_ftell(pb);
 499
 500     if (matroska->num_levels > 0) {
 501         MatroskaLevel *level = &matroska->levels[matroska->num_levels - 1];
 502         if (pos - level->start >= level->length) {
 503             matroska->num_levels--;
 504             return 1;
 505         }
 506     }
 507     return 0;
 508 }
 509
 510 /*
 511  * Read: an "EBML number", which is defined as a variable-length
 512  * array of bytes. The first byte indicates the length by giving a
 513  * number of 0-bits followed by a one. The position of the first
 514  * "one" bit inside the first byte indicates the length of this
 515  * number.
 516  * Returns: number of bytes read, < 0 on error
 517  */
 518 static int ebml_read_num(MatroskaDemuxContext *matroska, ByteIOContext *pb,
 519                          int max_size, uint64_t *number)
 520 {
 521     int len_mask = 0x80, read = 1, n = 1;
 522     int64_t total = 0;
 523
 524     /* The first byte tells us the length in bytes - get_byte() can normally
 525      * return 0, but since that's not a valid first ebmlID byte, we can
 526      * use it safely here to catch EOS. */
 527     if (!(total = get_byte(pb))) {
 528         /* we might encounter EOS here */
 529         if (!url_feof(pb)) {
 530             int64_t pos = url_ftell(pb);
 531             av_log(matroska->ctx, AV_LOG_ERROR,
 532                    "Read error at pos. %"PRIu64" (0x%"PRIx64")\n",
 533                    pos, pos);
 534         }
 535         return AVERROR(EIO); /* EOS or actual I/O error */
 536     }
 537
 538     /* get the length of the EBML number */
 539     while (read <= max_size && !(total & len_mask)) {
 540         read++;
 541         len_mask >>= 1;
 542     }
 543     if (read > max_size) {
 544         int64_t pos = url_ftell(pb) - 1;
 545         av_log(matroska->ctx, AV_LOG_ERROR,
 546                "Invalid EBML number size tag 0x%02x at pos %"PRIu64" (0x%"PRIx64")\n",
 547                (uint8_t) total, pos, pos);
 548         return AVERROR_INVALIDDATA;
 549     }
 550
 551     /* read out length */
 552     total &= ~len_mask;
 553     while (n++ < read)
 554         total = (total << 8) | get_byte(pb);
 555
 556     *number = total;
 557
 558     return read;
 559 }
 560
 561 /*
 562  * Read the next element as an unsigned int.
 563  * 0 is success, < 0 is failure.
 564  */
 565 static int ebml_read_uint(ByteIOContext *pb, int size, uint64_t *num)
 566 {
 567     int n = 0;
 568
 569     if (size < 1 || size > 8)
 570         return AVERROR_INVALIDDATA;
 571
 572     /* big-endian ordering; build up number */
 573     *num = 0;
 574     while (n++ < size)
 575         *num = (*num << 8) | get_byte(pb);
 576
 577     return 0;
 578 }
 579
 580 /*
 581  * Read the next element as a float.
 582  * 0 is success, < 0 is failure.
 583  */
 584 static int ebml_read_float(ByteIOContext *pb, int size, double *num)
 585 {
 586     if (size == 4) {
 587         *num= av_int2flt(get_be32(pb));
 588     } else if(size==8){
 589         *num= av_int2dbl(get_be64(pb));
 590     } else
 591         return AVERROR_INVALIDDATA;
 592
 593     return 0;
 594 }
 595
 596 /*
 597  * Read the next element as an ASCII string.
 598  * 0 is success, < 0 is failure.
 599  */
 600 static int ebml_read_ascii(ByteIOContext *pb, int size, char **str)
 601 {
 602     av_free(*str);
 603     /* EBML strings are usually not 0-terminated, so we allocate one
 604      * byte more, read the string and NULL-terminate it ourselves. */
 605     if (!(*str = av_malloc(size + 1)))
 606         return AVERROR(ENOMEM);
 607     if (get_buffer(pb, (uint8_t *) *str, size) != size) {
 608         av_free(*str);
 609         return AVERROR(EIO);
 610     }
 611     (*str)[size] = '\0';
 612
 613     return 0;
 614 }
 615
 616 /*
 617  * Read the next element as binary data.
 618  * 0 is success, < 0 is failure.
 619  */
 620 static int ebml_read_binary(ByteIOContext *pb, int length, EbmlBin *bin)
 621 {
 622     av_free(bin->data);
 623     if (!(bin->data = av_malloc(length)))
 624         return AVERROR(ENOMEM);
 625
 626     bin->size = length;
 627     bin->pos  = url_ftell(pb);
 628     if (get_buffer(pb, bin->data, length) != length)
 629         return AVERROR(EIO);
 630
 631     return 0;
 632 }
 633
 634 /*
 635  * Read the next element, but only the header. The contents
 636  * are supposed to be sub-elements which can be read separately.
 637  * 0 is success, < 0 is failure.
 638  */
 639 static int ebml_read_master(MatroskaDemuxContext *matroska, int length)
 640 {
 641     ByteIOContext *pb = matroska->ctx->pb;
 642     MatroskaLevel *level;
 643
 644     if (matroska->num_levels >= EBML_MAX_DEPTH) {
 645         av_log(matroska->ctx, AV_LOG_ERROR,
 646                "File moves beyond max. allowed depth (%d)\n", EBML_MAX_DEPTH);
 647         return AVERROR(ENOSYS);
 648     }
 649
 650     level = &matroska->levels[matroska->num_levels++];
 651     level->start = url_ftell(pb);
 652     level->length = length;
 653
 654     return 0;
 655 }
 656
 657 /*
 658  * Read signed/unsigned "EBML" numbers.
 659  * Return: number of bytes processed, < 0 on error
 660  */
 661 static int matroska_ebmlnum_uint(MatroskaDemuxContext *matroska,
 662                                  uint8_t *data, uint32_t size, uint64_t *num)
 663 {
 664     ByteIOContext pb;
 665     init_put_byte(&pb, data, size, 0, NULL, NULL, NULL, NULL);
 666     return ebml_read_num(matroska, &pb, 8, num);
 667 }
 668
 669 /*
 670  * Same as above, but signed.
 671  */
 672 static int matroska_ebmlnum_sint(MatroskaDemuxContext *matroska,
 673                                  uint8_t *data, uint32_t size, int64_t *num)
 674 {
 675     uint64_t unum;
 676     int res;
 677
 678     /* read as unsigned number first */
 679     if ((res = matroska_ebmlnum_uint(matroska, data, size, &unum)) < 0)
 680         return res;
 681
 682     /* make signed (weird way) */
 683     *num = unum - ((1LL << (7*res - 1)) - 1);
 684
 685     return res;
 686 }
 687
 688 static int ebml_parse_elem(MatroskaDemuxContext *matroska,
 689                            EbmlSyntax *syntax, void *data);
 690
 691 static int ebml_parse_id(MatroskaDemuxContext *matroska, EbmlSyntax *syntax,
 692                          uint32_t id, void *data)
 693 {
 694     int i;
 695     for (i=0; syntax[i].id; i++)
 696         if (id == syntax[i].id)
 697             break;
 698     if (!syntax[i].id && id != EBML_ID_VOID && id != EBML_ID_CRC32)
 699         av_log(matroska->ctx, AV_LOG_INFO, "Unknown entry 0x%X\n", id);
 700     return ebml_parse_elem(matroska, &syntax[i], data);
 701 }
 702
 703 static int ebml_parse(MatroskaDemuxContext *matroska, EbmlSyntax *syntax,
 704                       void *data)
 705 {
 706     uint64_t id;
 707     int res = ebml_read_num(matroska, matroska->ctx->pb, 4, &id);
 708     id |= 1 << 7*res;
 709     return res < 0 ? res : ebml_parse_id(matroska, syntax, id, data);
 710 }
 711
 712 static int ebml_parse_nest(MatroskaDemuxContext *matroska, EbmlSyntax *syntax,
 713                            void *data)
 714 {
 715     int i, res = 0;
 716
 717     for (i=0; syntax[i].id; i++)
 718         switch (syntax[i].type) {
 719         case EBML_UINT:
 720             *(uint64_t *)((char *)data+syntax[i].data_offset) = syntax[i].def.u;
 721             break;
 722         case EBML_FLOAT:
 723             *(double   *)((char *)data+syntax[i].data_offset) = syntax[i].def.f;
 724             break;
 725         case EBML_STR:
 726         case EBML_UTF8:
 727             *(char    **)((char *)data+syntax[i].data_offset) = av_strdup(syntax[i].def.s);
 728             break;
 729         }
 730
 731     while (!res && !ebml_level_end(matroska))
 732         res = ebml_parse(matroska, syntax, data);
 733
 734     return res;
 735 }
 736
 737 static int ebml_parse_elem(MatroskaDemuxContext *matroska,
 738                            EbmlSyntax *syntax, void *data)
 739 {
 740     ByteIOContext *pb = matroska->ctx->pb;
 741     uint32_t id = syntax->id;
 742     uint64_t length;
 743     int res;
 744
 745     data = (char *)data + syntax->data_offset;
 746     if (syntax->list_elem_size) {
 747         EbmlList *list = data;
 748         list->elem = av_realloc(list->elem, (list->nb_elem+1)*syntax->list_elem_size);
 749         data = (char*)list->elem + list->nb_elem*syntax->list_elem_size;
 750         memset(data, 0, syntax->list_elem_size);
 751         list->nb_elem++;
 752     }
 753
 754     if (syntax->type != EBML_PASS && syntax->type != EBML_STOP)
 755         if ((res = ebml_read_num(matroska, pb, 8, &length)) < 0)
 756             return res;
 757
 758     switch (syntax->type) {
 759     case EBML_UINT:  res = ebml_read_uint  (pb, length, data);  break;
 760     case EBML_FLOAT: res = ebml_read_float (pb, length, data);  break;
 761     case EBML_STR:
 762     case EBML_UTF8:  res = ebml_read_ascii (pb, length, data);  break;
 763     case EBML_BIN:   res = ebml_read_binary(pb, length, data);  break;
 764     case EBML_NEST:  if ((res=ebml_read_master(matroska, length)) < 0)
 765                          return res;
 766                      if (id == MATROSKA_ID_SEGMENT)
 767                          matroska->segment_start = url_ftell(matroska->ctx->pb);
 768                      return ebml_parse_nest(matroska, syntax->def.n, data);
 769     case EBML_PASS:  return ebml_parse_id(matroska, syntax->def.n, id, data);
 770     case EBML_STOP:  *(int *)data = 1;      return 1;
 771     default:         return url_fseek(pb,length,SEEK_CUR)<0 ? AVERROR(EIO) : 0;
 772     }
 773     if (res == AVERROR_INVALIDDATA)
 774         av_log(matroska->ctx, AV_LOG_ERROR, "Invalid element\n");
 775     else if (res == AVERROR(EIO))
 776         av_log(matroska->ctx, AV_LOG_ERROR, "Read error\n");
 777     return res;
 778 }
 779
 780 static void ebml_free(EbmlSyntax *syntax, void *data)
 781 {
 782     int i, j;
 783     for (i=0; syntax[i].id; i++) {
 784         void *data_off = (char *)data + syntax[i].data_offset;
 785         switch (syntax[i].type) {
 786         case EBML_STR:
 787         case EBML_UTF8:  av_freep(data_off);                      break;
 788         case EBML_BIN:   av_freep(&((EbmlBin *)data_off)->data);  break;
 789         case EBML_NEST:
 790             if (syntax[i].list_elem_size) {
 791                 EbmlList *list = data_off;
 792                 char *ptr = list->elem;
 793                 for (j=0; j<list->nb_elem; j++, ptr+=syntax[i].list_elem_size)
 794                     ebml_free(syntax[i].def.n, ptr);
 795                 av_free(list->elem);
 796             } else
 797                 ebml_free(syntax[i].def.n, data_off);
 798         default:  break;
 799         }
 800     }
 801 }
 802
 803
 804 /*
 805  * Autodetecting...
 806  */
 807 static int matroska_probe(AVProbeData *p)
 808 {
 809     uint64_t total = 0;
 810     int len_mask = 0x80, size = 1, n = 1;
 811     static const char probe_data[] = "matroska";
 812
 813     /* EBML header? */
 814     if (AV_RB32(p->buf) != EBML_ID_HEADER)
 815         return 0;
 816
 817     /* length of header */
 818     total = p->buf[4];
 819     while (size <= 8 && !(total & len_mask)) {
 820         size++;
 821         len_mask >>= 1;
 822     }
 823     if (size > 8)
 824       return 0;
 825     total &= (len_mask - 1);
 826     while (n < size)
 827         total = (total << 8) | p->buf[4 + n++];
 828
 829     /* Does the probe data contain the whole header? */
 830     if (p->buf_size < 4 + size + total)
 831       return 0;
 832
 833     /* The header must contain the document type 'matroska'. For now,
 834      * we don't parse the whole header but simply check for the
 835      * availability of that array of characters inside the header.
 836      * Not fully fool-proof, but good enough. */
 837     for (n = 4+size; n <= 4+size+total-(sizeof(probe_data)-1); n++)
 838         if (!memcmp(p->buf+n, probe_data, sizeof(probe_data)-1))
 839             return AVPROBE_SCORE_MAX;
 840
 841     return 0;
 842 }
 843
 844 static MatroskaTrack *matroska_find_track_by_num(MatroskaDemuxContext *matroska,
 845                                                  int num)
 846 {
 847     MatroskaTrack *tracks = matroska->tracks.elem;
 848     int i;
 849
 850     for (i=0; i < matroska->tracks.nb_elem; i++)
 851         if (tracks[i].num == num)
 852             return &tracks[i];
 853
 854     av_log(matroska->ctx, AV_LOG_ERROR, "Invalid track number %d\n", num);
 855     return NULL;
 856 }
 857
 858 static int matroska_decode_buffer(uint8_t** buf, int* buf_size,
 859                                   MatroskaTrack *track)
 860 {
 861     MatroskaTrackEncoding *encodings = track->encodings.elem;
 862     uint8_t* data = *buf;
 863     int isize = *buf_size;
 864     uint8_t* pkt_data = NULL;
 865     int pkt_size = isize;
 866     int result = 0;
 867     int olen;
 868
 869     switch (encodings[0].compression.algo) {
 870     case MATROSKA_TRACK_ENCODING_COMP_HEADERSTRIP:
 871         return encodings[0].compression.settings.size;
 872     case MATROSKA_TRACK_ENCODING_COMP_LZO:
 873         do {
 874             olen = pkt_size *= 3;
 875             pkt_data = av_realloc(pkt_data,
 876                                   pkt_size+LZO_OUTPUT_PADDING);
 877             result = lzo1x_decode(pkt_data, &olen, data, &isize);
 878         } while (result==LZO_OUTPUT_FULL && pkt_size<10000000);
 879         if (result)
 880             goto failed;
 881         pkt_size -= olen;
 882         break;
 883 #ifdef CONFIG_ZLIB
 884     case MATROSKA_TRACK_ENCODING_COMP_ZLIB: {
 885         z_stream zstream = {0};
 886         if (inflateInit(&zstream) != Z_OK)
 887             return -1;
 888         zstream.next_in = data;
 889         zstream.avail_in = isize;
 890         do {
 891             pkt_size *= 3;
 892             pkt_data = av_realloc(pkt_data, pkt_size);
 893             zstream.avail_out = pkt_size - zstream.total_out;
 894             zstream.next_out = pkt_data + zstream.total_out;
 895             result = inflate(&zstream, Z_NO_FLUSH);
 896         } while (result==Z_OK && pkt_size<10000000);
 897         pkt_size = zstream.total_out;
 898         inflateEnd(&zstream);
 899         if (result != Z_STREAM_END)
 900             goto failed;
 901         break;
 902     }
 903 #endif
 904 #ifdef CONFIG_BZLIB
 905     case MATROSKA_TRACK_ENCODING_COMP_BZLIB: {
 906         bz_stream bzstream = {0};
 907         if (BZ2_bzDecompressInit(&bzstream, 0, 0) != BZ_OK)
 908             return -1;
 909         bzstream.next_in = data;
 910         bzstream.avail_in = isize;
 911         do {
 912             pkt_size *= 3;
 913             pkt_data = av_realloc(pkt_data, pkt_size);
 914             bzstream.avail_out = pkt_size - bzstream.total_out_lo32;
 915             bzstream.next_out = pkt_data + bzstream.total_out_lo32;
 916             result = BZ2_bzDecompress(&bzstream);
 917         } while (result==BZ_OK && pkt_size<10000000);
 918         pkt_size = bzstream.total_out_lo32;
 919         BZ2_bzDecompressEnd(&bzstream);
 920         if (result != BZ_STREAM_END)
 921             goto failed;
 922         break;
 923     }
 924 #endif
 925     default:
 926         return -1;
 927     }
 928
 929     *buf = pkt_data;
 930     *buf_size = pkt_size;
 931     return 0;
 932  failed:
 933     av_free(pkt_data);
 934     return -1;
 935 }
 936
 937 static void matroska_fix_ass_packet(MatroskaDemuxContext *matroska,
 938                                     AVPacket *pkt, uint64_t display_duration)
 939 {
 940     char *line, *layer, *ptr = pkt->data, *end = ptr+pkt->size;
 941     for (; *ptr!=',' && ptr<end-1; ptr++);
 942     if (*ptr == ',')
 943         layer = ++ptr;
 944     for (; *ptr!=',' && ptr<end-1; ptr++);
 945     if (*ptr == ',') {
 946         int64_t end_pts = pkt->pts + display_duration;
 947         int sc = matroska->time_scale * pkt->pts / 10000000;
 948         int ec = matroska->time_scale * end_pts  / 10000000;
 949         int sh, sm, ss, eh, em, es, len;
 950         sh = sc/360000;  sc -= 360000*sh;
 951         sm = sc/  6000;  sc -=   6000*sm;
 952         ss = sc/   100;  sc -=    100*ss;
 953         eh = ec/360000;  ec -= 360000*eh;
 954         em = ec/  6000;  ec -=   6000*em;
 955         es = ec/   100;  ec -=    100*es;
 956         *ptr++ = '\0';
 957         len = 50 + end-ptr + FF_INPUT_BUFFER_PADDING_SIZE;
 958         if (!(line = av_malloc(len)))
 959             return;
 960         snprintf(line,len,"Dialogue: %s,%d:%02d:%02d.%02d,%d:%02d:%02d.%02d,%s\r\n",
 961                  layer, sh, sm, ss, sc, eh, em, es, ec, ptr);
 962         av_free(pkt->data);
 963         pkt->data = line;
 964         pkt->size = strlen(line);
 965     }
 966 }
 967
 968 static void matroska_merge_packets(AVPacket *out, AVPacket *in)
 969 {
 970     out->data = av_realloc(out->data, out->size+in->size);
 971     memcpy(out->data+out->size, in->data, in->size);
 972     out->size += in->size;
 973     av_destruct_packet(in);
 974     av_free(in);
 975 }
 976
 977 static void matroska_convert_tags(AVFormatContext *s, EbmlList *list)
 978 {
 979     MatroskaTag *tags = list->elem;
 980     int i, j;
 981
 982     for (i=0; i < list->nb_elem; i++) {
 983         for (j=0; j < ARRAY_SIZE(metadata); j++){
 984             if (!strcmp(tags[i].name, metadata[j].name)) {
 985                 int *ptr = (int *)((char *)s + metadata[j].offset);
 986                 if (*ptr)  continue;
 987                 if (metadata[j].size > sizeof(int))
 988                     av_strlcpy((char *)ptr, tags[i].string, metadata[j].size);
 989                 else
 990                     *ptr = atoi(tags[i].string);
 991             }
 992         }
 993         if (tags[i].sub.nb_elem)
 994             matroska_convert_tags(s, &tags[i].sub);
 995     }
 996 }
 997
 998 static void matroska_execute_seekhead(MatroskaDemuxContext *matroska)
 999 {
1000     EbmlList *seekhead_list = &matroska->seekhead;
1001     MatroskaSeekhead *seekhead = seekhead_list->elem;
1002     uint32_t level_up = matroska->level_up;
1003     int64_t before_pos = url_ftell(matroska->ctx->pb);
1004     MatroskaLevel level;
1005     int i;
1006
1007     for (i=0; i<seekhead_list->nb_elem; i++) {
1008         int64_t offset = seekhead[i].pos + matroska->segment_start;
1009
1010         if (seekhead[i].pos <= before_pos
1011             || seekhead[i].id == MATROSKA_ID_SEEKHEAD
1012             || seekhead[i].id == MATROSKA_ID_CLUSTER)
1013             continue;
1014
1015         /* seek */
1016         if (url_fseek(matroska->ctx->pb, offset, SEEK_SET) != offset)
1017             continue;
1018
1019         /* We don't want to lose our seekhead level, so we add
1020          * a dummy. This is a crude hack. */
1021         if (matroska->num_levels == EBML_MAX_DEPTH) {
1022             av_log(matroska->ctx, AV_LOG_INFO,
1023                    "Max EBML element depth (%d) reached, "
1024                    "cannot parse further.\n", EBML_MAX_DEPTH);
1025             break;
1026         }
1027
1028         level.start = 0;
1029         level.length = (uint64_t)-1;
1030         matroska->levels[matroska->num_levels] = level;
1031         matroska->num_levels++;
1032
1033         ebml_parse(matroska, matroska_segment, matroska);
1034
1035         /* remove dummy level */
1036         while (matroska->num_levels) {
1037             uint64_t length = matroska->levels[--matroska->num_levels].length;
1038             if (length == (uint64_t)-1)
1039                 break;
1040         }
1041     }
1042
1043     /* seek back */
1044     url_fseek(matroska->ctx->pb, before_pos, SEEK_SET);
1045     matroska->level_up = level_up;
1046 }
1047
1048 static int matroska_aac_profile(char *codec_id)
1049 {
1050     static const char * const aac_profiles[] = { "MAIN", "LC", "SSR" };
1051     int profile;
1052
1053     for (profile=0; profile<ARRAY_SIZE(aac_profiles); profile++)
1054         if (strstr(codec_id, aac_profiles[profile]))
1055             break;
1056     return profile + 1;
1057 }
1058
1059 static int matroska_aac_sri(int samplerate)
1060 {
1061     int sri;
1062
1063     for (sri=0; sri<ARRAY_SIZE(ff_mpeg4audio_sample_rates); sri++)
1064         if (ff_mpeg4audio_sample_rates[sri] == samplerate)
1065             break;
1066     return sri;
1067 }
1068
1069 static int matroska_read_header(AVFormatContext *s, AVFormatParameters *ap)
1070 {
1071     MatroskaDemuxContext *matroska = s->priv_data;
1072     EbmlList *attachements_list = &matroska->attachments;
1073     MatroskaAttachement *attachements;
1074     EbmlList *chapters_list = &matroska->chapters;
1075     MatroskaChapter *chapters;
1076     MatroskaTrack *tracks;
1077     EbmlList *index_list;
1078     MatroskaIndex *index;
1079     Ebml ebml = { 0 };
1080     AVStream *st;
1081     int i, j;
1082
1083     matroska->ctx = s;
1084
1085     /* First read the EBML header. */
1086     if (ebml_parse(matroska, ebml_syntax, &ebml)
1087         || ebml.version > EBML_VERSION       || ebml.max_size > sizeof(uint64_t)
1088         || ebml.id_length > sizeof(uint32_t) || strcmp(ebml.doctype, "matroska")
1089         || ebml.doctype_version > 2) {
1090         av_log(matroska->ctx, AV_LOG_ERROR,
1091                "EBML header using unsupported features\n"
1092                "(EBML version %"PRIu64", doctype %s, doc version %"PRIu64")\n",
1093                ebml.version, ebml.doctype, ebml.doctype_version);
1094         return AVERROR_NOFMT;
1095     }
1096     ebml_free(ebml_syntax, &ebml);
1097
1098     /* The next thing is a segment. */
1099     if (ebml_parse(matroska, matroska_segments, matroska) < 0)
1100         return -1;
1101     matroska_execute_seekhead(matroska);
1102
1103     if (matroska->duration)
1104         matroska->ctx->duration = matroska->duration * matroska->time_scale
1105                                   * 1000 / AV_TIME_BASE;
1106     if (matroska->title)
1107         strncpy(matroska->ctx->title, matroska->title,
1108                 sizeof(matroska->ctx->title)-1);
1109     matroska_convert_tags(s, &matroska->tags);
1110
1111     tracks = matroska->tracks.elem;
1112     for (i=0; i < matroska->tracks.nb_elem; i++) {
1113         MatroskaTrack *track = &tracks[i];
1114         enum CodecID codec_id = CODEC_ID_NONE;
1115         EbmlList *encodings_list = &tracks->encodings;
1116         MatroskaTrackEncoding *encodings = encodings_list->elem;
1117         uint8_t *extradata = NULL;
1118         int extradata_size = 0;
1119         int extradata_offset = 0;
1120
1121         /* Apply some sanity checks. */
1122         if (track->type != MATROSKA_TRACK_TYPE_VIDEO &&
1123             track->type != MATROSKA_TRACK_TYPE_AUDIO &&
1124             track->type != MATROSKA_TRACK_TYPE_SUBTITLE) {
1125             av_log(matroska->ctx, AV_LOG_INFO,
1126                    "Unknown or unsupported track type %"PRIu64"\n",
1127                    track->type);
1128             continue;
1129         }
1130         if (track->codec_id == NULL)
1131             continue;
1132
1133         if (track->type == MATROSKA_TRACK_TYPE_VIDEO) {
1134             if (!track->default_duration)
1135                 track->default_duration = 1000000000/track->video.frame_rate;
1136             if (!track->video.display_width)
1137                 track->video.display_width = track->video.pixel_width;
1138             if (!track->video.display_height)
1139                 track->video.display_height = track->video.pixel_height;
1140         } else if (track->type == MATROSKA_TRACK_TYPE_AUDIO) {
1141             if (!track->audio.out_samplerate)
1142                 track->audio.out_samplerate = track->audio.samplerate;
1143         }
1144         if (encodings_list->nb_elem > 1) {
1145             av_log(matroska->ctx, AV_LOG_ERROR,
1146                    "Multiple combined encodings no supported");
1147         } else if (encodings_list->nb_elem == 1) {
1148             if (encodings[0].type ||
1149                 (encodings[0].compression.algo != MATROSKA_TRACK_ENCODING_COMP_HEADERSTRIP &&
1150 #ifdef CONFIG_ZLIB
1151                  encodings[0].compression.algo != MATROSKA_TRACK_ENCODING_COMP_ZLIB &&
1152 #endif
1153 #ifdef CONFIG_BZLIB
1154                  encodings[0].compression.algo != MATROSKA_TRACK_ENCODING_COMP_BZLIB &&
1155 #endif
1156                  encodings[0].compression.algo != MATROSKA_TRACK_ENCODING_COMP_LZO)) {
1157                 encodings[0].scope = 0;
1158                 av_log(matroska->ctx, AV_LOG_ERROR,
1159                        "Unsupported encoding type");
1160             } else if (track->codec_priv.size && encodings[0].scope&2) {
1161                 uint8_t *codec_priv = track->codec_priv.data;
1162                 int offset = matroska_decode_buffer(&track->codec_priv.data,
1163                                                     &track->codec_priv.size,
1164                                                     track);
1165                 if (offset < 0) {
1166                     track->codec_priv.data = NULL;
1167                     track->codec_priv.size = 0;
1168                     av_log(matroska->ctx, AV_LOG_ERROR,
1169                            "Failed to decode codec private data\n");
1170                 } else if (offset > 0) {
1171                     track->codec_priv.data = av_malloc(track->codec_priv.size + offset);
1172                     memcpy(track->codec_priv.data,
1173                            encodings[0].compression.settings.data, offset);
1174                     memcpy(track->codec_priv.data+offset, codec_priv,
1175                            track->codec_priv.size);
1176                     track->codec_priv.size += offset;
1177                 }
1178                 if (codec_priv != track->codec_priv.data)
1179                     av_free(codec_priv);
1180             }
1181         }
1182
1183         for(j=0; ff_mkv_codec_tags[j].id != CODEC_ID_NONE; j++){
1184             if(!strncmp(ff_mkv_codec_tags[j].str, track->codec_id,
1185                         strlen(ff_mkv_codec_tags[j].str))){
1186                 codec_id= ff_mkv_codec_tags[j].id;
1187                 break;
1188             }
1189         }
1190
1191         st = track->stream = av_new_stream(s, 0);
1192         if (st == NULL)
1193             return AVERROR(ENOMEM);
1194
1195         if (!strcmp(track->codec_id, "V_MS/VFW/FOURCC")
1196             && track->codec_priv.size >= 40
1197             && track->codec_priv.data != NULL) {
1198             track->video.fourcc = AV_RL32(track->codec_priv.data + 16);
1199             codec_id = codec_get_id(codec_bmp_tags, track->video.fourcc);
1200         } else if (!strcmp(track->codec_id, "A_MS/ACM")
1201                    && track->codec_priv.size >= 18
1202                    && track->codec_priv.data != NULL) {
1203             uint16_t tag = AV_RL16(track->codec_priv.data);
1204             codec_id = codec_get_id(codec_wav_tags, tag);
1205         } else if (!strcmp(track->codec_id, "V_QUICKTIME")
1206                    && (track->codec_priv.size >= 86)
1207                    && (track->codec_priv.data != NULL)) {
1208             track->video.fourcc = AV_RL32(track->codec_priv.data);
1209             codec_id=codec_get_id(codec_movvideo_tags, track->video.fourcc);
1210         } else if (codec_id == CODEC_ID_PCM_S16BE) {
1211             switch (track->audio.bitdepth) {
1212             case  8:  codec_id = CODEC_ID_PCM_U8;     break;
1213             case 24:  codec_id = CODEC_ID_PCM_S24BE;  break;
1214             case 32:  codec_id = CODEC_ID_PCM_S32BE;  break;
1215             }
1216         } else if (codec_id == CODEC_ID_PCM_S16LE) {
1217             switch (track->audio.bitdepth) {
1218             case  8:  codec_id = CODEC_ID_PCM_U8;     break;
1219             case 24:  codec_id = CODEC_ID_PCM_S24LE;  break;
1220             case 32:  codec_id = CODEC_ID_PCM_S32LE;  break;
1221             }
1222         } else if (codec_id==CODEC_ID_PCM_F32LE && track->audio.bitdepth==64) {
1223             codec_id = CODEC_ID_PCM_F64LE;
1224         } else if (codec_id == CODEC_ID_AAC && !track->codec_priv.size) {
1225             int profile = matroska_aac_profile(track->codec_id);
1226             int sri = matroska_aac_sri(track->audio.samplerate);
1227             extradata = av_malloc(5);
1228             if (extradata == NULL)
1229                 return AVERROR(ENOMEM);
1230             extradata[0] = (profile << 3) | ((sri&0x0E) >> 1);
1231             extradata[1] = ((sri&0x01) << 7) | (track->audio.channels<<3);
1232             if (strstr(track->codec_id, "SBR")) {
1233                 sri = matroska_aac_sri(track->audio.out_samplerate);
1234                 extradata[2] = 0x56;
1235                 extradata[3] = 0xE5;
1236                 extradata[4] = 0x80 | (sri<<3);
1237                 extradata_size = 5;
1238             } else
1239                 extradata_size = 2;
1240         } else if (codec_id == CODEC_ID_TTA) {
1241             ByteIOContext b;
1242             extradata_size = 30;
1243             extradata = av_mallocz(extradata_size);
1244             if (extradata == NULL)
1245                 return AVERROR(ENOMEM);
1246             init_put_byte(&b, extradata, extradata_size, 1,
1247                           NULL, NULL, NULL, NULL);
1248             put_buffer(&b, "TTA1", 4);
1249             put_le16(&b, 1);
1250             put_le16(&b, track->audio.channels);
1251             put_le16(&b, track->audio.bitdepth);
1252             put_le32(&b, track->audio.out_samplerate);
1253             put_le32(&b, matroska->ctx->duration * track->audio.out_samplerate);
1254         } else if (codec_id == CODEC_ID_RV10 || codec_id == CODEC_ID_RV20 ||
1255                    codec_id == CODEC_ID_RV30 || codec_id == CODEC_ID_RV40) {
1256             extradata_offset = 26;
1257             track->codec_priv.size -= extradata_offset;
1258         } else if (codec_id == CODEC_ID_RA_144) {
1259             track->audio.out_samplerate = 8000;
1260             track->audio.channels = 1;
1261         } else if (codec_id == CODEC_ID_RA_288 || codec_id == CODEC_ID_COOK ||
1262                    codec_id == CODEC_ID_ATRAC3) {
1263             ByteIOContext b;
1264
1265             init_put_byte(&b, track->codec_priv.data,track->codec_priv.size,
1266                           0, NULL, NULL, NULL, NULL);
1267             url_fskip(&b, 24);
1268             track->audio.coded_framesize = get_be32(&b);
1269             url_fskip(&b, 12);
1270             track->audio.sub_packet_h    = get_be16(&b);
1271             track->audio.frame_size      = get_be16(&b);
1272             track->audio.sub_packet_size = get_be16(&b);
1273             track->audio.buf = av_malloc(track->audio.frame_size * track->audio.sub_packet_h);
1274             if (codec_id == CODEC_ID_RA_288) {
1275                 st->codec->block_align = track->audio.coded_framesize;
1276                 track->codec_priv.size = 0;
1277             } else {
1278                 st->codec->block_align = track->audio.sub_packet_size;
1279                 extradata_offset = 78;
1280                 track->codec_priv.size -= extradata_offset;
1281             }
1282         }
1283
1284         if (codec_id == CODEC_ID_NONE)
1285             av_log(matroska->ctx, AV_LOG_INFO,
1286                    "Unknown/unsupported CodecID %s.\n", track->codec_id);
1287
1288         if (track->time_scale < 0.01)
1289             track->time_scale = 1.0;
1290         av_set_pts_info(st, 64, matroska->time_scale*track->time_scale, 1000*1000*1000); /* 64 bit pts in ns */
1291
1292         st->codec->codec_id = codec_id;
1293         st->start_time = 0;
1294         if (strcmp(track->language, "und"))
1295             av_strlcpy(st->language, track->language, 4);
1296
1297         if (track->flag_default)
1298             st->disposition |= AV_DISPOSITION_DEFAULT;
1299
1300         if (track->default_duration)
1301             av_reduce(&st->codec->time_base.num, &st->codec->time_base.den,
1302                       track->default_duration, 1000000000, 30000);
1303
1304         if(extradata){
1305             st->codec->extradata = extradata;
1306             st->codec->extradata_size = extradata_size;
1307         } else if(track->codec_priv.data && track->codec_priv.size > 0){
1308             st->codec->extradata = av_malloc(track->codec_priv.size);
1309             if(st->codec->extradata == NULL)
1310                 return AVERROR(ENOMEM);
1311             st->codec->extradata_size = track->codec_priv.size;
1312             memcpy(st->codec->extradata,
1313                    track->codec_priv.data + extradata_offset,
1314                    track->codec_priv.size);
1315         }
1316
1317         if (track->type == MATROSKA_TRACK_TYPE_VIDEO) {
1318             st->codec->codec_type = CODEC_TYPE_VIDEO;
1319             st->codec->codec_tag  = track->video.fourcc;
1320             st->codec->width  = track->video.pixel_width;
1321             st->codec->height = track->video.pixel_height;
1322             av_reduce(&st->sample_aspect_ratio.num,
1323                       &st->sample_aspect_ratio.den,
1324                       st->codec->height * track->video.display_width,
1325                       st->codec-> width * track->video.display_height,
1326                       255);
1327             st->need_parsing = AVSTREAM_PARSE_HEADERS;
1328         } else if (track->type == MATROSKA_TRACK_TYPE_AUDIO) {
1329             st->codec->codec_type = CODEC_TYPE_AUDIO;
1330             st->codec->sample_rate = track->audio.out_samplerate;
1331             st->codec->channels = track->audio.channels;
1332         } else if (track->type == MATROSKA_TRACK_TYPE_SUBTITLE) {
1333             st->codec->codec_type = CODEC_TYPE_SUBTITLE;
1334         }
1335     }
1336
1337     attachements = attachements_list->elem;
1338     for (j=0; j<attachements_list->nb_elem; j++) {
1339         if (!(attachements[j].filename && attachements[j].mime &&
1340               attachements[j].bin.data && attachements[j].bin.size > 0)) {
1341             av_log(matroska->ctx, AV_LOG_ERROR, "incomplete attachment\n");
1342         } else {
1343             AVStream *st = av_new_stream(s, 0);
1344             if (st == NULL)
1345                 break;
1346             st->filename          = av_strdup(attachements[j].filename);
1347             st->codec->codec_id = CODEC_ID_NONE;
1348             st->codec->codec_type = CODEC_TYPE_ATTACHMENT;
1349             st->codec->extradata  = av_malloc(attachements[j].bin.size);
1350             if(st->codec->extradata == NULL)
1351                 break;
1352             st->codec->extradata_size = attachements[j].bin.size;
1353             memcpy(st->codec->extradata, attachements[j].bin.data, attachements[j].bin.size);
1354
1355             for (i=0; ff_mkv_mime_tags[i].id != CODEC_ID_NONE; i++) {
1356                 if (!strncmp(ff_mkv_mime_tags[i].str, attachements[j].mime,
1357                              strlen(ff_mkv_mime_tags[i].str))) {
1358                     st->codec->codec_id = ff_mkv_mime_tags[i].id;
1359                     break;
1360                 }
1361             }
1362         }
1363     }
1364
1365     chapters = chapters_list->elem;
1366     for (i=0; i<chapters_list->nb_elem; i++)
1367         if (chapters[i].start != AV_NOPTS_VALUE && chapters[i].uid)
1368             ff_new_chapter(s, chapters[i].uid, (AVRational){1, 1000000000},
1369                            chapters[i].start, chapters[i].end,
1370                            chapters[i].title);
1371
1372     index_list = &matroska->index;
1373     index = index_list->elem;
1374     for (i=0; i<index_list->nb_elem; i++) {
1375         EbmlList *pos_list = &index[i].pos;
1376         MatroskaIndexPos *pos = pos_list->elem;
1377         for (j=0; j<pos_list->nb_elem; j++) {
1378             MatroskaTrack *track = matroska_find_track_by_num(matroska,
1379                                                               pos[j].track);
1380             if (track && track->stream)
1381                 av_add_index_entry(track->stream,
1382                                    pos[j].pos + matroska->segment_start,
1383                                    index[i].time, 0, 0, AVINDEX_KEYFRAME);
1384         }
1385     }
1386
1387     return 0;
1388 }
1389
1390 /*
1391  * Put one packet in an application-supplied AVPacket struct.
1392  * Returns 0 on success or -1 on failure.
1393  */
1394 static int matroska_deliver_packet(MatroskaDemuxContext *matroska,
1395                                    AVPacket *pkt)
1396 {
1397     if (matroska->num_packets > 0) {
1398         memcpy(pkt, matroska->packets[0], sizeof(AVPacket));
1399         av_free(matroska->packets[0]);
1400         if (matroska->num_packets > 1) {
1401             memmove(&matroska->packets[0], &matroska->packets[1],
1402                     (matroska->num_packets - 1) * sizeof(AVPacket *));
1403             matroska->packets =
1404                 av_realloc(matroska->packets, (matroska->num_packets - 1) *
1405                            sizeof(AVPacket *));
1406         } else {
1407             av_freep(&matroska->packets);
1408         }
1409         matroska->num_packets--;
1410         return 0;
1411     }
1412
1413     return -1;
1414 }
1415
1416 /*
1417  * Free all packets in our internal queue.
1418  */
1419 static void matroska_clear_queue(MatroskaDemuxContext *matroska)
1420 {
1421     if (matroska->packets) {
1422         int n;
1423         for (n = 0; n < matroska->num_packets; n++) {
1424             av_free_packet(matroska->packets[n]);
1425             av_free(matroska->packets[n]);
1426         }
1427         av_freep(&matroska->packets);
1428         matroska->num_packets = 0;
1429     }
1430 }
1431
1432 static int matroska_parse_block(MatroskaDemuxContext *matroska, uint8_t *data,
1433                                 int size, int64_t pos, uint64_t cluster_time,
1434                                 uint64_t duration, int is_keyframe,
1435                                 int64_t cluster_pos)
1436 {
1437     uint64_t timecode = AV_NOPTS_VALUE;
1438     MatroskaTrack *track;
1439     int res = 0;
1440     AVStream *st;
1441     AVPacket *pkt;
1442     int16_t block_time;
1443     uint32_t *lace_size = NULL;
1444     int n, flags, laces = 0;
1445     uint64_t num;
1446
1447     if ((n = matroska_ebmlnum_uint(matroska, data, size, &num)) < 0) {
1448         av_log(matroska->ctx, AV_LOG_ERROR, "EBML block data error\n");
1449         return res;
1450     }
1451     data += n;
1452     size -= n;
1453
1454     track = matroska_find_track_by_num(matroska, num);
1455     if (size <= 3 || !track || !track->stream) {
1456         av_log(matroska->ctx, AV_LOG_INFO,
1457                "Invalid stream %"PRIu64" or size %u\n", num, size);
1458         return res;
1459     }
1460     st = track->stream;
1461     if (st->discard >= AVDISCARD_ALL)
1462         return res;
1463     if (duration == AV_NOPTS_VALUE)
1464         duration = track->default_duration / matroska->time_scale;
1465
1466     block_time = AV_RB16(data);
1467     data += 2;
1468     flags = *data++;
1469     size -= 3;
1470     if (is_keyframe == -1)
1471         is_keyframe = flags & 0x80 ? PKT_FLAG_KEY : 0;
1472
1473     if (cluster_time != (uint64_t)-1
1474         && (block_time >= 0 || cluster_time >= -block_time)) {
1475         timecode = cluster_time + block_time;
1476         if (track->type == MATROSKA_TRACK_TYPE_SUBTITLE
1477             && timecode < track->end_timecode)
1478             is_keyframe = 0;  /* overlapping subtitles are not key frame */
1479         if (is_keyframe)
1480             av_add_index_entry(st, cluster_pos, timecode, 0,0,AVINDEX_KEYFRAME);
1481         track->end_timecode = FFMAX(track->end_timecode, timecode+duration);
1482     }
1483
1484     if (matroska->skip_to_keyframe && track->type != MATROSKA_TRACK_TYPE_SUBTITLE) {
1485         if (!is_keyframe || timecode < matroska->skip_to_timecode)
1486             return res;
1487         matroska->skip_to_keyframe = 0;
1488     }
1489
1490     switch ((flags & 0x06) >> 1) {
1491         case 0x0: /* no lacing */
1492             laces = 1;
1493             lace_size = av_mallocz(sizeof(int));
1494             lace_size[0] = size;
1495             break;
1496
1497         case 0x1: /* Xiph lacing */
1498         case 0x2: /* fixed-size lacing */
1499         case 0x3: /* EBML lacing */
1500             assert(size>0); // size <=3 is checked before size-=3 above
1501             laces = (*data) + 1;
1502             data += 1;
1503             size -= 1;
1504             lace_size = av_mallocz(laces * sizeof(int));
1505
1506             switch ((flags & 0x06) >> 1) {
1507                 case 0x1: /* Xiph lacing */ {
1508                     uint8_t temp;
1509                     uint32_t total = 0;
1510                     for (n = 0; res == 0 && n < laces - 1; n++) {
1511                         while (1) {
1512                             if (size == 0) {
1513                                 res = -1;
1514                                 break;
1515                             }
1516                             temp = *data;
1517                             lace_size[n] += temp;
1518                             data += 1;
1519                             size -= 1;
1520                             if (temp != 0xff)
1521                                 break;
1522                         }
1523                         total += lace_size[n];
1524                     }
1525                     lace_size[n] = size - total;
1526                     break;
1527                 }
1528
1529                 case 0x2: /* fixed-size lacing */
1530                     for (n = 0; n < laces; n++)
1531                         lace_size[n] = size / laces;
1532                     break;
1533
1534                 case 0x3: /* EBML lacing */ {
1535                     uint32_t total;
1536                     n = matroska_ebmlnum_uint(matroska, data, size, &num);
1537                     if (n < 0) {
1538                         av_log(matroska->ctx, AV_LOG_INFO,
1539                                "EBML block data error\n");
1540                         break;
1541                     }
1542                     data += n;
1543                     size -= n;
1544                     total = lace_size[0] = num;
1545                     for (n = 1; res == 0 && n < laces - 1; n++) {
1546                         int64_t snum;
1547                         int r;
1548                         r = matroska_ebmlnum_sint(matroska, data, size, &snum);
1549                         if (r < 0) {
1550                             av_log(matroska->ctx, AV_LOG_INFO,
1551                                    "EBML block data error\n");
1552                             break;
1553                         }
1554                         data += r;
1555                         size -= r;
1556                         lace_size[n] = lace_size[n - 1] + snum;
1557                         total += lace_size[n];
1558                     }
1559                     lace_size[n] = size - total;
1560                     break;
1561                 }
1562             }
1563             break;
1564     }
1565
1566     if (res == 0) {
1567         for (n = 0; n < laces; n++) {
1568             if (st->codec->codec_id == CODEC_ID_RA_288 ||
1569                 st->codec->codec_id == CODEC_ID_COOK ||
1570                 st->codec->codec_id == CODEC_ID_ATRAC3) {
1571                 int a = st->codec->block_align;
1572                 int sps = track->audio.sub_packet_size;
1573                 int cfs = track->audio.coded_framesize;
1574                 int h = track->audio.sub_packet_h;
1575                 int y = track->audio.sub_packet_cnt;
1576                 int w = track->audio.frame_size;
1577                 int x;
1578
1579                 if (!track->audio.pkt_cnt) {
1580                     if (st->codec->codec_id == CODEC_ID_RA_288)
1581                         for (x=0; x<h/2; x++)
1582                             memcpy(track->audio.buf+x*2*w+y*cfs,
1583                                    data+x*cfs, cfs);
1584                     else
1585                         for (x=0; x<w/sps; x++)
1586                             memcpy(track->audio.buf+sps*(h*x+((h+1)/2)*(y&1)+(y>>1)), data+x*sps, sps);
1587
1588                     if (++track->audio.sub_packet_cnt >= h) {
1589                         track->audio.sub_packet_cnt = 0;
1590                         track->audio.pkt_cnt = h*w / a;
1591                     }
1592                 }
1593                 while (track->audio.pkt_cnt) {
1594                     pkt = av_mallocz(sizeof(AVPacket));
1595                     av_new_packet(pkt, a);
1596                     memcpy(pkt->data, track->audio.buf
1597                            + a * (h*w / a - track->audio.pkt_cnt--), a);
1598                     pkt->pos = pos;
1599                     pkt->stream_index = st->index;
1600                     dynarray_add(&matroska->packets,&matroska->num_packets,pkt);
1601                 }
1602             } else {
1603                 MatroskaTrackEncoding *encodings = track->encodings.elem;
1604                 int offset = 0, pkt_size = lace_size[n];
1605                 uint8_t *pkt_data = data;
1606
1607                 if (encodings && encodings->scope & 1) {
1608                     offset = matroska_decode_buffer(&pkt_data,&pkt_size, track);
1609                     if (offset < 0)
1610                         continue;
1611                 }
1612
1613                 pkt = av_mallocz(sizeof(AVPacket));
1614                 /* XXX: prevent data copy... */
1615                 if (av_new_packet(pkt, pkt_size+offset) < 0) {
1616                     av_free(pkt);
1617                     res = AVERROR(ENOMEM);
1618                     n = laces-1;
1619                     break;
1620                 }
1621                 if (offset)
1622                     memcpy (pkt->data, encodings->compression.settings.data, offset);
1623                 memcpy (pkt->data+offset, pkt_data, pkt_size);
1624
1625                 if (pkt_data != data)
1626                     av_free(pkt_data);
1627
1628                 if (n == 0)
1629                     pkt->flags = is_keyframe;
1630                 pkt->stream_index = st->index;
1631
1632                 pkt->pts = timecode;
1633                 pkt->pos = pos;
1634                 if (st->codec->codec_id == CODEC_ID_TEXT)
1635                     pkt->convergence_duration = duration;
1636                 else if (track->type != MATROSKA_TRACK_TYPE_SUBTITLE)
1637                     pkt->duration = duration;
1638
1639                 if (st->codec->codec_id == CODEC_ID_SSA)
1640                     matroska_fix_ass_packet(matroska, pkt, duration);
1641
1642                 if (matroska->prev_pkt &&
1643                     timecode != AV_NOPTS_VALUE &&
1644                     matroska->prev_pkt->pts == timecode &&
1645                     matroska->prev_pkt->stream_index == st->index)
1646                     matroska_merge_packets(matroska->prev_pkt, pkt);
1647                 else {
1648                     dynarray_add(&matroska->packets,&matroska->num_packets,pkt);
1649                     matroska->prev_pkt = pkt;
1650                 }
1651             }
1652
1653             if (timecode != AV_NOPTS_VALUE)
1654                 timecode = duration ? timecode + duration : AV_NOPTS_VALUE;
1655             data += lace_size[n];
1656         }
1657     }
1658
1659     av_free(lace_size);
1660     return res;
1661 }
1662
1663 static int matroska_parse_cluster(MatroskaDemuxContext *matroska)
1664 {
1665     MatroskaCluster cluster = { 0 };
1666     EbmlList *blocks_list;
1667     MatroskaBlock *blocks;
1668     int i, res;
1669     int64_t pos = url_ftell(matroska->ctx->pb);
1670     matroska->prev_pkt = NULL;
1671     if (matroska->has_cluster_id){
1672         /* For the first cluster we parse, its ID was already read as
1673            part of matroska_read_header(), so don't read it again */
1674         res = ebml_parse_id(matroska, matroska_clusters,
1675                             MATROSKA_ID_CLUSTER, &cluster);
1676         pos -= 4;  /* sizeof the ID which was already read */
1677         matroska->has_cluster_id = 0;
1678     } else
1679         res = ebml_parse(matroska, matroska_clusters, &cluster);
1680     blocks_list = &cluster.blocks;
1681     blocks = blocks_list->elem;
1682     for (i=0; i<blocks_list->nb_elem; i++)
1683         if (blocks[i].bin.size > 0)
1684             res=matroska_parse_block(matroska,
1685                                      blocks[i].bin.data, blocks[i].bin.size,
1686                                      blocks[i].bin.pos,  cluster.timecode,
1687                                      blocks[i].duration, !blocks[i].reference,
1688                                      pos);
1689     ebml_free(matroska_cluster, &cluster);
1690     if (res < 0)  matroska->done = 1;
1691     return res;
1692 }
1693
1694 static int matroska_read_packet(AVFormatContext *s, AVPacket *pkt)
1695 {
1696     MatroskaDemuxContext *matroska = s->priv_data;
1697
1698     while (matroska_deliver_packet(matroska, pkt)) {
1699         if (matroska->done)
1700             return AVERROR(EIO);
1701         matroska_parse_cluster(matroska);
1702     }
1703
1704     return 0;
1705 }
1706
1707 static int matroska_read_seek(AVFormatContext *s, int stream_index,
1708                               int64_t timestamp, int flags)
1709 {
1710     MatroskaDemuxContext *matroska = s->priv_data;
1711     MatroskaTrack *tracks = matroska->tracks.elem;
1712     AVStream *st = s->streams[stream_index];
1713     int i, index, index_sub, index_min;
1714
1715     if (!st->nb_index_entries)
1716         return 0;
1717     timestamp = FFMAX(timestamp, st->index_entries[0].timestamp);
1718
1719     if ((index = av_index_search_timestamp(st, timestamp, flags)) < 0) {
1720         url_fseek(s->pb, st->index_entries[st->nb_index_entries-1].pos, SEEK_SET);
1721         while ((index = av_index_search_timestamp(st, timestamp, flags)) < 0) {
1722             matroska_clear_queue(matroska);
1723             if (matroska_parse_cluster(matroska) < 0)
1724                 break;
1725         }
1726     }
1727
1728     matroska_clear_queue(matroska);
1729     if (index < 0)
1730         return 0;
1731
1732     index_min = index;
1733     for (i=0; i < matroska->tracks.nb_elem; i++) {
1734         tracks[i].end_timecode = 0;
1735         if (tracks[i].type == MATROSKA_TRACK_TYPE_SUBTITLE
1736             && !tracks[i].stream->discard != AVDISCARD_ALL) {
1737             index_sub = av_index_search_timestamp(tracks[i].stream, st->index_entries[index].timestamp, AVSEEK_FLAG_BACKWARD);
1738             if (index_sub >= 0
1739                 && st->index_entries[index_sub].pos < st->index_entries[index_min].pos
1740                 && st->index_entries[index].timestamp - st->index_entries[index_sub].timestamp < 30000000000/matroska->time_scale)
1741                 index_min = index_sub;
1742         }
1743     }
1744
1745     url_fseek(s->pb, st->index_entries[index_min].pos, SEEK_SET);
1746     matroska->skip_to_keyframe = !(flags & AVSEEK_FLAG_ANY);
1747     matroska->skip_to_timecode = st->index_entries[index].timestamp;
1748     matroska->done = 0;
1749     av_update_cur_dts(s, st, st->index_entries[index].timestamp);
1750     return 0;
1751 }
1752
1753 static int matroska_read_close(AVFormatContext *s)
1754 {
1755     MatroskaDemuxContext *matroska = s->priv_data;
1756     MatroskaTrack *tracks = matroska->tracks.elem;
1757     int n;
1758
1759     matroska_clear_queue(matroska);
1760
1761     for (n=0; n < matroska->tracks.nb_elem; n++)
1762         if (tracks[n].type == MATROSKA_TRACK_TYPE_AUDIO)
1763             av_free(tracks[n].audio.buf);
1764     ebml_free(matroska_segment, matroska);
1765
1766     return 0;
1767 }
1768
1769 AVInputFormat matroska_demuxer = {
1770     "matroska",
1771     NULL_IF_CONFIG_SMALL("Matroska file format"),
1772     sizeof(MatroskaDemuxContext),
1773     matroska_probe,
1774     matroska_read_header,
1775     matroska_read_packet,
1776     matroska_read_close,
1777     matroska_read_seek,
1778 };