git.sesse.net Git - ffmpeg/blob - 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/intreadwrite.h"
  40 #include "libavutil/avstring.h"
  41 #include "libavutil/lzo.h"
  42 #if CONFIG_ZLIB
  43 #include <zlib.h>
  44 #endif
  45 #if CONFIG_BZLIB
  46 #include <bzlib.h>
  47 #endif
  48
  49 typedef enum {
  50     EBML_NONE,
  51     EBML_UINT,
  52     EBML_FLOAT,
  53     EBML_STR,
  54     EBML_UTF8,
  55     EBML_BIN,
  56     EBML_NEST,
  57     EBML_PASS,
  58     EBML_STOP,
  59 } EbmlType;
  60
  61 typedef const struct EbmlSyntax {
  62     uint32_t id;
  63     EbmlType type;
  64     int list_elem_size;
  65     int data_offset;
  66     union {
  67         uint64_t    u;
  68         double      f;
  69         const char *s;
  70         const struct EbmlSyntax *n;
  71     } def;
  72 } EbmlSyntax;
  73
  74 typedef struct {
  75     int nb_elem;
  76     void *elem;
  77 } EbmlList;
  78
  79 typedef struct {
  80     int      size;
  81     uint8_t *data;
  82     int64_t  pos;
  83 } EbmlBin;
  84
  85 typedef struct {
  86     uint64_t version;
  87     uint64_t max_size;
  88     uint64_t id_length;
  89     char    *doctype;
  90     uint64_t doctype_version;
  91 } Ebml;
  92
  93 typedef struct {
  94     uint64_t algo;
  95     EbmlBin  settings;
  96 } MatroskaTrackCompression;
  97
  98 typedef struct {
  99     uint64_t scope;
 100     uint64_t type;
 101     MatroskaTrackCompression compression;
 102 } MatroskaTrackEncoding;
 103
 104 typedef struct {
 105     double   frame_rate;
 106     uint64_t display_width;
 107     uint64_t display_height;
 108     uint64_t pixel_width;
 109     uint64_t pixel_height;
 110     uint64_t fourcc;
 111 } MatroskaTrackVideo;
 112
 113 typedef struct {
 114     double   samplerate;
 115     double   out_samplerate;
 116     uint64_t bitdepth;
 117     uint64_t channels;
 118
 119     /* real audio header (extracted from extradata) */
 120     int      coded_framesize;
 121     int      sub_packet_h;
 122     int      frame_size;
 123     int      sub_packet_size;
 124     int      sub_packet_cnt;
 125     int      pkt_cnt;
 126     uint8_t *buf;
 127 } MatroskaTrackAudio;
 128
 129 typedef struct {
 130     uint64_t num;
 131     uint64_t type;
 132     char    *codec_id;
 133     EbmlBin  codec_priv;
 134     char    *language;
 135     double time_scale;
 136     uint64_t default_duration;
 137     uint64_t flag_default;
 138     MatroskaTrackVideo video;
 139     MatroskaTrackAudio audio;
 140     EbmlList encodings;
 141
 142     AVStream *stream;
 143     int64_t end_timecode;
 144 } MatroskaTrack;
 145
 146 typedef struct {
 147     char *filename;
 148     char *mime;
 149     EbmlBin bin;
 150 } MatroskaAttachement;
 151
 152 typedef struct {
 153     uint64_t start;
 154     uint64_t end;
 155     uint64_t uid;
 156     char    *title;
 157 } MatroskaChapter;
 158
 159 typedef struct {
 160     uint64_t track;
 161     uint64_t pos;
 162 } MatroskaIndexPos;
 163
 164 typedef struct {
 165     uint64_t time;
 166     EbmlList pos;
 167 } MatroskaIndex;
 168
 169 typedef struct {
 170     char *name;
 171     char *string;
 172     EbmlList sub;
 173 } MatroskaTag;
 174
 175 typedef struct {
 176     uint64_t id;
 177     uint64_t pos;
 178 } MatroskaSeekhead;
 179
 180 typedef struct {
 181     uint64_t start;
 182     uint64_t length;
 183 } MatroskaLevel;
 184
 185 typedef struct {
 186     AVFormatContext *ctx;
 187
 188     /* EBML stuff */
 189     int num_levels;
 190     MatroskaLevel levels[EBML_MAX_DEPTH];
 191     int level_up;
 192
 193     uint64_t time_scale;
 194     double   duration;
 195     char    *title;
 196     EbmlList tracks;
 197     EbmlList attachments;
 198     EbmlList chapters;
 199     EbmlList index;
 200     EbmlList tags;
 201     EbmlList seekhead;
 202
 203     /* byte position of the segment inside the stream */
 204     int64_t segment_start;
 205
 206     /* the packet queue */
 207     AVPacket **packets;
 208     int num_packets;
 209     AVPacket *prev_pkt;
 210
 211     int done;
 212     int has_cluster_id;
 213
 214     /* What to skip before effectively reading a packet. */
 215     int skip_to_keyframe;
 216     uint64_t skip_to_timecode;
 217 } MatroskaDemuxContext;
 218
 219 typedef struct {
 220     uint64_t duration;
 221     int64_t  reference;
 222     EbmlBin  bin;
 223 } MatroskaBlock;
 224
 225 typedef struct {
 226     uint64_t timecode;
 227     EbmlList blocks;
 228 } MatroskaCluster;
 229
 230 static EbmlSyntax ebml_header[] = {
 231     { EBML_ID_EBMLREADVERSION,        EBML_UINT, 0, offsetof(Ebml,version), {.u=EBML_VERSION} },
 232     { EBML_ID_EBMLMAXSIZELENGTH,      EBML_UINT, 0, offsetof(Ebml,max_size), {.u=8} },
 233     { EBML_ID_EBMLMAXIDLENGTH,        EBML_UINT, 0, offsetof(Ebml,id_length), {.u=4} },
 234     { EBML_ID_DOCTYPE,                EBML_STR,  0, offsetof(Ebml,doctype), {.s="(none)"} },
 235     { EBML_ID_DOCTYPEREADVERSION,     EBML_UINT, 0, offsetof(Ebml,doctype_version), {.u=1} },
 236     { EBML_ID_EBMLVERSION,            EBML_NONE },
 237     { EBML_ID_DOCTYPEVERSION,         EBML_NONE },
 238     { 0 }
 239 };
 240
 241 static EbmlSyntax ebml_syntax[] = {
 242     { EBML_ID_HEADER,                 EBML_NEST, 0, 0, {.n=ebml_header} },
 243     { 0 }
 244 };
 245
 246 static EbmlSyntax matroska_info[] = {
 247     { MATROSKA_ID_TIMECODESCALE,      EBML_UINT,  0, offsetof(MatroskaDemuxContext,time_scale), {.u=1000000} },
 248     { MATROSKA_ID_DURATION,           EBML_FLOAT, 0, offsetof(MatroskaDemuxContext,duration) },
 249     { MATROSKA_ID_TITLE,              EBML_UTF8,  0, offsetof(MatroskaDemuxContext,title) },
 250     { MATROSKA_ID_WRITINGAPP,         EBML_NONE },
 251     { MATROSKA_ID_MUXINGAPP,          EBML_NONE },
 252     { MATROSKA_ID_DATEUTC,            EBML_NONE },
 253     { MATROSKA_ID_SEGMENTUID,         EBML_NONE },
 254     { 0 }
 255 };
 256
 257 static EbmlSyntax matroska_track_video[] = {
 258     { MATROSKA_ID_VIDEOFRAMERATE,     EBML_FLOAT,0, offsetof(MatroskaTrackVideo,frame_rate) },
 259     { MATROSKA_ID_VIDEODISPLAYWIDTH,  EBML_UINT, 0, offsetof(MatroskaTrackVideo,display_width) },
 260     { MATROSKA_ID_VIDEODISPLAYHEIGHT, EBML_UINT, 0, offsetof(MatroskaTrackVideo,display_height) },
 261     { MATROSKA_ID_VIDEOPIXELWIDTH,    EBML_UINT, 0, offsetof(MatroskaTrackVideo,pixel_width) },
 262     { MATROSKA_ID_VIDEOPIXELHEIGHT,   EBML_UINT, 0, offsetof(MatroskaTrackVideo,pixel_height) },
 263     { MATROSKA_ID_VIDEOCOLORSPACE,    EBML_UINT, 0, offsetof(MatroskaTrackVideo,fourcc) },
 264     { MATROSKA_ID_VIDEOPIXELCROPB,    EBML_NONE },
 265     { MATROSKA_ID_VIDEOPIXELCROPT,    EBML_NONE },
 266     { MATROSKA_ID_VIDEOPIXELCROPL,    EBML_NONE },
 267     { MATROSKA_ID_VIDEOPIXELCROPR,    EBML_NONE },
 268     { MATROSKA_ID_VIDEODISPLAYUNIT,   EBML_NONE },
 269     { MATROSKA_ID_VIDEOFLAGINTERLACED,EBML_NONE },
 270     { MATROSKA_ID_VIDEOSTEREOMODE,    EBML_NONE },
 271     { MATROSKA_ID_VIDEOASPECTRATIO,   EBML_NONE },
 272     { 0 }
 273 };
 274
 275 static EbmlSyntax matroska_track_audio[] = {
 276     { MATROSKA_ID_AUDIOSAMPLINGFREQ,  EBML_FLOAT,0, offsetof(MatroskaTrackAudio,samplerate), {.f=8000.0} },
 277     { MATROSKA_ID_AUDIOOUTSAMPLINGFREQ,EBML_FLOAT,0,offsetof(MatroskaTrackAudio,out_samplerate) },
 278     { MATROSKA_ID_AUDIOBITDEPTH,      EBML_UINT, 0, offsetof(MatroskaTrackAudio,bitdepth) },
 279     { MATROSKA_ID_AUDIOCHANNELS,      EBML_UINT, 0, offsetof(MatroskaTrackAudio,channels), {.u=1} },
 280     { 0 }
 281 };
 282
 283 static EbmlSyntax matroska_track_encoding_compression[] = {
 284     { MATROSKA_ID_ENCODINGCOMPALGO,   EBML_UINT, 0, offsetof(MatroskaTrackCompression,algo), {.u=0} },
 285     { MATROSKA_ID_ENCODINGCOMPSETTINGS,EBML_BIN, 0, offsetof(MatroskaTrackCompression,settings) },
 286     { 0 }
 287 };
 288
 289 static EbmlSyntax matroska_track_encoding[] = {
 290     { MATROSKA_ID_ENCODINGSCOPE,      EBML_UINT, 0, offsetof(MatroskaTrackEncoding,scope), {.u=1} },
 291     { MATROSKA_ID_ENCODINGTYPE,       EBML_UINT, 0, offsetof(MatroskaTrackEncoding,type), {.u=0} },
 292     { MATROSKA_ID_ENCODINGCOMPRESSION,EBML_NEST, 0, offsetof(MatroskaTrackEncoding,compression), {.n=matroska_track_encoding_compression} },
 293     { MATROSKA_ID_ENCODINGORDER,      EBML_NONE },
 294     { 0 }
 295 };
 296
 297 static EbmlSyntax matroska_track_encodings[] = {
 298     { MATROSKA_ID_TRACKCONTENTENCODING, EBML_NEST, sizeof(MatroskaTrackEncoding), offsetof(MatroskaTrack,encodings), {.n=matroska_track_encoding} },
 299     { 0 }
 300 };
 301
 302 static EbmlSyntax matroska_track[] = {
 303     { MATROSKA_ID_TRACKNUMBER,          EBML_UINT, 0, offsetof(MatroskaTrack,num) },
 304     { MATROSKA_ID_TRACKTYPE,            EBML_UINT, 0, offsetof(MatroskaTrack,type) },
 305     { MATROSKA_ID_CODECID,              EBML_STR,  0, offsetof(MatroskaTrack,codec_id) },
 306     { MATROSKA_ID_CODECPRIVATE,         EBML_BIN,  0, offsetof(MatroskaTrack,codec_priv) },
 307     { MATROSKA_ID_TRACKLANGUAGE,        EBML_UTF8, 0, offsetof(MatroskaTrack,language), {.s="eng"} },
 308     { MATROSKA_ID_TRACKDEFAULTDURATION, EBML_UINT, 0, offsetof(MatroskaTrack,default_duration) },
 309     { MATROSKA_ID_TRACKTIMECODESCALE,   EBML_FLOAT,0, offsetof(MatroskaTrack,time_scale), {.f=1.0} },
 310     { MATROSKA_ID_TRACKFLAGDEFAULT,     EBML_UINT, 0, offsetof(MatroskaTrack,flag_default), {.u=1} },
 311     { MATROSKA_ID_TRACKVIDEO,           EBML_NEST, 0, offsetof(MatroskaTrack,video), {.n=matroska_track_video} },
 312     { MATROSKA_ID_TRACKAUDIO,           EBML_NEST, 0, offsetof(MatroskaTrack,audio), {.n=matroska_track_audio} },
 313     { MATROSKA_ID_TRACKCONTENTENCODINGS,EBML_NEST, 0, 0, {.n=matroska_track_encodings} },
 314     { MATROSKA_ID_TRACKUID,             EBML_NONE },
 315     { MATROSKA_ID_TRACKNAME,            EBML_NONE },
 316     { MATROSKA_ID_TRACKFLAGENABLED,     EBML_NONE },
 317     { MATROSKA_ID_TRACKFLAGFORCED,      EBML_NONE },
 318     { MATROSKA_ID_TRACKFLAGLACING,      EBML_NONE },
 319     { MATROSKA_ID_CODECNAME,            EBML_NONE },
 320     { MATROSKA_ID_CODECDECODEALL,       EBML_NONE },
 321     { MATROSKA_ID_CODECINFOURL,         EBML_NONE },
 322     { MATROSKA_ID_CODECDOWNLOADURL,     EBML_NONE },
 323     { MATROSKA_ID_TRACKMINCACHE,        EBML_NONE },
 324     { MATROSKA_ID_TRACKMAXCACHE,        EBML_NONE },
 325     { MATROSKA_ID_TRACKMAXBLKADDID,     EBML_NONE },
 326     { 0 }
 327 };
 328
 329 static EbmlSyntax matroska_tracks[] = {
 330     { MATROSKA_ID_TRACKENTRY,         EBML_NEST, sizeof(MatroskaTrack), offsetof(MatroskaDemuxContext,tracks), {.n=matroska_track} },
 331     { 0 }
 332 };
 333
 334 static EbmlSyntax matroska_attachment[] = {
 335     { MATROSKA_ID_FILENAME,           EBML_UTF8, 0, offsetof(MatroskaAttachement,filename) },
 336     { MATROSKA_ID_FILEMIMETYPE,       EBML_STR,  0, offsetof(MatroskaAttachement,mime) },
 337     { MATROSKA_ID_FILEDATA,           EBML_BIN,  0, offsetof(MatroskaAttachement,bin) },
 338     { MATROSKA_ID_FILEDESC,           EBML_NONE },
 339     { MATROSKA_ID_FILEUID,            EBML_NONE },
 340     { 0 }
 341 };
 342
 343 static EbmlSyntax matroska_attachments[] = {
 344     { MATROSKA_ID_ATTACHEDFILE,       EBML_NEST, sizeof(MatroskaAttachement), offsetof(MatroskaDemuxContext,attachments), {.n=matroska_attachment} },
 345     { 0 }
 346 };
 347
 348 static EbmlSyntax matroska_chapter_display[] = {
 349     { MATROSKA_ID_CHAPSTRING,         EBML_UTF8, 0, offsetof(MatroskaChapter,title) },
 350     { MATROSKA_ID_CHAPLANG,           EBML_NONE },
 351     { 0 }
 352 };
 353
 354 static EbmlSyntax matroska_chapter_entry[] = {
 355     { MATROSKA_ID_CHAPTERTIMESTART,   EBML_UINT, 0, offsetof(MatroskaChapter,start), {.u=AV_NOPTS_VALUE} },
 356     { MATROSKA_ID_CHAPTERTIMEEND,     EBML_UINT, 0, offsetof(MatroskaChapter,end), {.u=AV_NOPTS_VALUE} },
 357     { MATROSKA_ID_CHAPTERUID,         EBML_UINT, 0, offsetof(MatroskaChapter,uid) },
 358     { MATROSKA_ID_CHAPTERDISPLAY,     EBML_NEST, 0, 0, {.n=matroska_chapter_display} },
 359     { MATROSKA_ID_CHAPTERFLAGHIDDEN,  EBML_NONE },
 360     { MATROSKA_ID_CHAPTERFLAGENABLED, EBML_NONE },
 361     { MATROSKA_ID_CHAPTERPHYSEQUIV,   EBML_NONE },
 362     { MATROSKA_ID_CHAPTERATOM,        EBML_NONE },
 363     { 0 }
 364 };
 365
 366 static EbmlSyntax matroska_chapter[] = {
 367     { MATROSKA_ID_CHAPTERATOM,        EBML_NEST, sizeof(MatroskaChapter), offsetof(MatroskaDemuxContext,chapters), {.n=matroska_chapter_entry} },
 368     { MATROSKA_ID_EDITIONUID,         EBML_NONE },
 369     { MATROSKA_ID_EDITIONFLAGHIDDEN,  EBML_NONE },
 370     { MATROSKA_ID_EDITIONFLAGDEFAULT, EBML_NONE },
 371     { MATROSKA_ID_EDITIONFLAGORDERED, EBML_NONE },
 372     { 0 }
 373 };
 374
 375 static EbmlSyntax matroska_chapters[] = {
 376     { MATROSKA_ID_EDITIONENTRY,       EBML_NEST, 0, 0, {.n=matroska_chapter} },
 377     { 0 }
 378 };
 379
 380 static EbmlSyntax matroska_index_pos[] = {
 381     { MATROSKA_ID_CUETRACK,           EBML_UINT, 0, offsetof(MatroskaIndexPos,track) },
 382     { MATROSKA_ID_CUECLUSTERPOSITION, EBML_UINT, 0, offsetof(MatroskaIndexPos,pos)   },
 383     { MATROSKA_ID_CUEBLOCKNUMBER,     EBML_NONE },
 384     { 0 }
 385 };
 386
 387 static EbmlSyntax matroska_index_entry[] = {
 388     { MATROSKA_ID_CUETIME,            EBML_UINT, 0, offsetof(MatroskaIndex,time) },
 389     { MATROSKA_ID_CUETRACKPOSITION,   EBML_NEST, sizeof(MatroskaIndexPos), offsetof(MatroskaIndex,pos), {.n=matroska_index_pos} },
 390     { 0 }
 391 };
 392
 393 static EbmlSyntax matroska_index[] = {
 394     { MATROSKA_ID_POINTENTRY,         EBML_NEST, sizeof(MatroskaIndex), offsetof(MatroskaDemuxContext,index), {.n=matroska_index_entry} },
 395     { 0 }
 396 };
 397
 398 static EbmlSyntax matroska_simpletag[] = {
 399     { MATROSKA_ID_TAGNAME,            EBML_UTF8, 0, offsetof(MatroskaTag,name) },
 400     { MATROSKA_ID_TAGSTRING,          EBML_UTF8, 0, offsetof(MatroskaTag,string) },
 401     { MATROSKA_ID_SIMPLETAG,          EBML_NEST, sizeof(MatroskaTag), offsetof(MatroskaTag,sub), {.n=matroska_simpletag} },
 402     { MATROSKA_ID_TAGLANG,            EBML_NONE },
 403     { MATROSKA_ID_TAGDEFAULT,         EBML_NONE },
 404     { 0 }
 405 };
 406
 407 static EbmlSyntax matroska_tag[] = {
 408     { MATROSKA_ID_SIMPLETAG,          EBML_NEST, sizeof(MatroskaTag), 0, {.n=matroska_simpletag} },
 409     { MATROSKA_ID_TAGTARGETS,         EBML_NONE },
 410     { 0 }
 411 };
 412
 413 static EbmlSyntax matroska_tags[] = {
 414     { MATROSKA_ID_TAG,                EBML_NEST, 0, offsetof(MatroskaDemuxContext,tags), {.n=matroska_tag} },
 415     { 0 }
 416 };
 417
 418 static EbmlSyntax matroska_seekhead_entry[] = {
 419     { MATROSKA_ID_SEEKID,             EBML_UINT, 0, offsetof(MatroskaSeekhead,id) },
 420     { MATROSKA_ID_SEEKPOSITION,       EBML_UINT, 0, offsetof(MatroskaSeekhead,pos), {.u=-1} },
 421     { 0 }
 422 };
 423
 424 static EbmlSyntax matroska_seekhead[] = {
 425     { MATROSKA_ID_SEEKENTRY,          EBML_NEST, sizeof(MatroskaSeekhead), offsetof(MatroskaDemuxContext,seekhead), {.n=matroska_seekhead_entry} },
 426     { 0 }
 427 };
 428
 429 static EbmlSyntax matroska_segment[] = {
 430     { MATROSKA_ID_INFO,           EBML_NEST, 0, 0, {.n=matroska_info       } },
 431     { MATROSKA_ID_TRACKS,         EBML_NEST, 0, 0, {.n=matroska_tracks     } },
 432     { MATROSKA_ID_ATTACHMENTS,    EBML_NEST, 0, 0, {.n=matroska_attachments} },
 433     { MATROSKA_ID_CHAPTERS,       EBML_NEST, 0, 0, {.n=matroska_chapters   } },
 434     { MATROSKA_ID_CUES,           EBML_NEST, 0, 0, {.n=matroska_index      } },
 435     { MATROSKA_ID_TAGS,           EBML_NEST, 0, 0, {.n=matroska_tags       } },
 436     { MATROSKA_ID_SEEKHEAD,       EBML_NEST, 0, 0, {.n=matroska_seekhead   } },
 437     { MATROSKA_ID_CLUSTER,        EBML_STOP, 0, offsetof(MatroskaDemuxContext,has_cluster_id) },
 438     { 0 }
 439 };
 440
 441 static EbmlSyntax matroska_segments[] = {
 442     { MATROSKA_ID_SEGMENT,        EBML_NEST, 0, 0, {.n=matroska_segment    } },
 443     { 0 }
 444 };
 445
 446 static EbmlSyntax matroska_blockgroup[] = {
 447     { MATROSKA_ID_BLOCK,          EBML_BIN,  0, offsetof(MatroskaBlock,bin) },
 448     { MATROSKA_ID_SIMPLEBLOCK,    EBML_BIN,  0, offsetof(MatroskaBlock,bin) },
 449     { MATROSKA_ID_BLOCKDURATION,  EBML_UINT, 0, offsetof(MatroskaBlock,duration), {.u=AV_NOPTS_VALUE} },
 450     { MATROSKA_ID_BLOCKREFERENCE, EBML_UINT, 0, offsetof(MatroskaBlock,reference) },
 451     { 0 }
 452 };
 453
 454 static EbmlSyntax matroska_cluster[] = {
 455     { MATROSKA_ID_CLUSTERTIMECODE,EBML_UINT,0, offsetof(MatroskaCluster,timecode) },
 456     { MATROSKA_ID_BLOCKGROUP,     EBML_NEST, sizeof(MatroskaBlock), offsetof(MatroskaCluster,blocks), {.n=matroska_blockgroup} },
 457     { MATROSKA_ID_SIMPLEBLOCK,    EBML_PASS, sizeof(MatroskaBlock), offsetof(MatroskaCluster,blocks), {.n=matroska_blockgroup} },
 458     { MATROSKA_ID_CLUSTERPOSITION,EBML_NONE },
 459     { MATROSKA_ID_CLUSTERPREVSIZE,EBML_NONE },
 460     { 0 }
 461 };
 462
 463 static EbmlSyntax matroska_clusters[] = {
 464     { MATROSKA_ID_CLUSTER,        EBML_NEST, 0, 0, {.n=matroska_cluster} },
 465     { MATROSKA_ID_INFO,           EBML_NONE },
 466     { MATROSKA_ID_CUES,           EBML_NONE },
 467     { MATROSKA_ID_TAGS,           EBML_NONE },
 468     { MATROSKA_ID_SEEKHEAD,       EBML_NONE },
 469     { 0 }
 470 };
 471
 472 #define SIZE_OFF(x) sizeof(((AVFormatContext*)0)->x),offsetof(AVFormatContext,x)
 473 const struct {
 474     const char name[16];
 475     int   size;
 476     int   offset;
 477 } metadata[] = {
 478     { "TITLE",           SIZE_OFF(title)      },
 479     { "ARTIST",          SIZE_OFF(author)     },
 480     { "WRITTEN_BY",      SIZE_OFF(author)     },
 481     { "LEAD_PERFORMER",  SIZE_OFF(author)     },
 482     { "COPYRIGHT",       SIZE_OFF(copyright)  },
 483     { "COMMENT",         SIZE_OFF(comment)    },
 484     { "ALBUM",           SIZE_OFF(album)      },
 485     { "DATE_WRITTEN",    SIZE_OFF(year)       },
 486     { "DATE_RELEASED",   SIZE_OFF(year)       },
 487     { "PART_NUMBER",     SIZE_OFF(track)      },
 488     { "GENRE",           SIZE_OFF(genre)      },
 489 };
 490
 491 /*
 492  * Return: Whether we reached the end of a level in the hierarchy or not.
 493  */
 494 static int ebml_level_end(MatroskaDemuxContext *matroska)
 495 {
 496     ByteIOContext *pb = matroska->ctx->pb;
 497     int64_t pos = url_ftell(pb);
 498
 499     if (matroska->num_levels > 0) {
 500         MatroskaLevel *level = &matroska->levels[matroska->num_levels - 1];
 501         if (pos - level->start >= level->length) {
 502             matroska->num_levels--;
 503             return 1;
 504         }
 505     }
 506     return 0;
 507 }
 508
 509 /*
 510  * Read: an "EBML number", which is defined as a variable-length
 511  * array of bytes. The first byte indicates the length by giving a
 512  * number of 0-bits followed by a one. The position of the first
 513  * "one" bit inside the first byte indicates the length of this
 514  * number.
 515  * Returns: number of bytes read, < 0 on error
 516  */
 517 static int ebml_read_num(MatroskaDemuxContext *matroska, ByteIOContext *pb,
 518                          int max_size, uint64_t *number)
 519 {
 520     int len_mask = 0x80, read = 1, n = 1;
 521     int64_t total = 0;
 522
 523     /* The first byte tells us the length in bytes - get_byte() can normally
 524      * return 0, but since that's not a valid first ebmlID byte, we can
 525      * use it safely here to catch EOS. */
 526     if (!(total = get_byte(pb))) {
 527         /* we might encounter EOS here */
 528         if (!url_feof(pb)) {
 529             int64_t pos = url_ftell(pb);
 530             av_log(matroska->ctx, AV_LOG_ERROR,
 531                    "Read error at pos. %"PRIu64" (0x%"PRIx64")\n",
 532                    pos, pos);
 533         }
 534         return AVERROR(EIO); /* EOS or actual I/O error */
 535     }
 536
 537     /* get the length of the EBML number */
 538     while (read <= max_size && !(total & len_mask)) {
 539         read++;
 540         len_mask >>= 1;
 541     }
 542     if (read > max_size) {
 543         int64_t pos = url_ftell(pb) - 1;
 544         av_log(matroska->ctx, AV_LOG_ERROR,
 545                "Invalid EBML number size tag 0x%02x at pos %"PRIu64" (0x%"PRIx64")\n",
 546                (uint8_t) total, pos, pos);
 547         return AVERROR_INVALIDDATA;
 548     }
 549
 550     /* read out length */
 551     total &= ~len_mask;
 552     while (n++ < read)
 553         total = (total << 8) | get_byte(pb);
 554
 555     *number = total;
 556
 557     return read;
 558 }
 559
 560 /*
 561  * Read the next element as an unsigned int.
 562  * 0 is success, < 0 is failure.
 563  */
 564 static int ebml_read_uint(ByteIOContext *pb, int size, uint64_t *num)
 565 {
 566     int n = 0;
 567
 568     if (size < 1 || size > 8)
 569         return AVERROR_INVALIDDATA;
 570
 571     /* big-endian ordering; build up number */
 572     *num = 0;
 573     while (n++ < size)
 574         *num = (*num << 8) | get_byte(pb);
 575
 576     return 0;
 577 }
 578
 579 /*
 580  * Read the next element as a float.
 581  * 0 is success, < 0 is failure.
 582  */
 583 static int ebml_read_float(ByteIOContext *pb, int size, double *num)
 584 {
 585     if (size == 4) {
 586         *num= av_int2flt(get_be32(pb));
 587     } else if(size==8){
 588         *num= av_int2dbl(get_be64(pb));
 589     } else
 590         return AVERROR_INVALIDDATA;
 591
 592     return 0;
 593 }
 594
 595 /*
 596  * Read the next element as an ASCII string.
 597  * 0 is success, < 0 is failure.
 598  */
 599 static int ebml_read_ascii(ByteIOContext *pb, int size, char **str)
 600 {
 601     av_free(*str);
 602     /* EBML strings are usually not 0-terminated, so we allocate one
 603      * byte more, read the string and NULL-terminate it ourselves. */
 604     if (!(*str = av_malloc(size + 1)))
 605         return AVERROR(ENOMEM);
 606     if (get_buffer(pb, (uint8_t *) *str, size) != size) {
 607         av_free(*str);
 608         return AVERROR(EIO);
 609     }
 610     (*str)[size] = '\0';
 611
 612     return 0;
 613 }
 614
 615 /*
 616  * Read the next element as binary data.
 617  * 0 is success, < 0 is failure.
 618  */
 619 static int ebml_read_binary(ByteIOContext *pb, int length, EbmlBin *bin)
 620 {
 621     av_free(bin->data);
 622     if (!(bin->data = av_malloc(length)))
 623         return AVERROR(ENOMEM);
 624
 625     bin->size = length;
 626     bin->pos  = url_ftell(pb);
 627     if (get_buffer(pb, bin->data, length) != length)
 628         return AVERROR(EIO);
 629
 630     return 0;
 631 }
 632
 633 /*
 634  * Read the next element, but only the header. The contents
 635  * are supposed to be sub-elements which can be read separately.
 636  * 0 is success, < 0 is failure.
 637  */
 638 static int ebml_read_master(MatroskaDemuxContext *matroska, int length)
 639 {
 640     ByteIOContext *pb = matroska->ctx->pb;
 641     MatroskaLevel *level;
 642
 643     if (matroska->num_levels >= EBML_MAX_DEPTH) {
 644         av_log(matroska->ctx, AV_LOG_ERROR,
 645                "File moves beyond max. allowed depth (%d)\n", EBML_MAX_DEPTH);
 646         return AVERROR(ENOSYS);
 647     }
 648
 649     level = &matroska->levels[matroska->num_levels++];
 650     level->start = url_ftell(pb);
 651     level->length = length;
 652
 653     return 0;
 654 }
 655
 656 /*
 657  * Read signed/unsigned "EBML" numbers.
 658  * Return: number of bytes processed, < 0 on error
 659  */
 660 static int matroska_ebmlnum_uint(MatroskaDemuxContext *matroska,
 661                                  uint8_t *data, uint32_t size, uint64_t *num)
 662 {
 663     ByteIOContext pb;
 664     init_put_byte(&pb, data, size, 0, NULL, NULL, NULL, NULL);
 665     return ebml_read_num(matroska, &pb, 8, num);
 666 }
 667
 668 /*
 669  * Same as above, but signed.
 670  */
 671 static int matroska_ebmlnum_sint(MatroskaDemuxContext *matroska,
 672                                  uint8_t *data, uint32_t size, int64_t *num)
 673 {
 674     uint64_t unum;
 675     int res;
 676
 677     /* read as unsigned number first */
 678     if ((res = matroska_ebmlnum_uint(matroska, data, size, &unum)) < 0)
 679         return res;
 680
 681     /* make signed (weird way) */
 682     *num = unum - ((1LL << (7*res - 1)) - 1);
 683
 684     return res;
 685 }
 686
 687 static int ebml_parse_elem(MatroskaDemuxContext *matroska,
 688                            EbmlSyntax *syntax, void *data);
 689
 690 static int ebml_parse_id(MatroskaDemuxContext *matroska, EbmlSyntax *syntax,
 691                          uint32_t id, void *data)
 692 {
 693     int i;
 694     for (i=0; syntax[i].id; i++)
 695         if (id == syntax[i].id)
 696             break;
 697     if (!syntax[i].id && id != EBML_ID_VOID && id != EBML_ID_CRC32)
 698         av_log(matroska->ctx, AV_LOG_INFO, "Unknown entry 0x%X\n", id);
 699     return ebml_parse_elem(matroska, &syntax[i], data);
 700 }
 701
 702 static int ebml_parse(MatroskaDemuxContext *matroska, EbmlSyntax *syntax,
 703                       void *data)
 704 {
 705     uint64_t id;
 706     int res = ebml_read_num(matroska, matroska->ctx->pb, 4, &id);
 707     id |= 1 << 7*res;
 708     return res < 0 ? res : ebml_parse_id(matroska, syntax, id, data);
 709 }
 710
 711 static int ebml_parse_nest(MatroskaDemuxContext *matroska, EbmlSyntax *syntax,
 712                            void *data)
 713 {
 714     int i, res = 0;
 715
 716     for (i=0; syntax[i].id; i++)
 717         switch (syntax[i].type) {
 718         case EBML_UINT:
 719             *(uint64_t *)((char *)data+syntax[i].data_offset) = syntax[i].def.u;
 720             break;
 721         case EBML_FLOAT:
 722             *(double   *)((char *)data+syntax[i].data_offset) = syntax[i].def.f;
 723             break;
 724         case EBML_STR:
 725         case EBML_UTF8:
 726             *(char    **)((char *)data+syntax[i].data_offset) = av_strdup(syntax[i].def.s);
 727             break;
 728         }
 729
 730     while (!res && !ebml_level_end(matroska))
 731         res = ebml_parse(matroska, syntax, data);
 732
 733     return res;
 734 }
 735
 736 static int ebml_parse_elem(MatroskaDemuxContext *matroska,
 737                            EbmlSyntax *syntax, void *data)
 738 {
 739     ByteIOContext *pb = matroska->ctx->pb;
 740     uint32_t id = syntax->id;
 741     uint64_t length;
 742     int res;
 743
 744     data = (char *)data + syntax->data_offset;
 745     if (syntax->list_elem_size) {
 746         EbmlList *list = data;
 747         list->elem = av_realloc(list->elem, (list->nb_elem+1)*syntax->list_elem_size);
 748         data = (char*)list->elem + list->nb_elem*syntax->list_elem_size;
 749         memset(data, 0, syntax->list_elem_size);
 750         list->nb_elem++;
 751     }
 752
 753     if (syntax->type != EBML_PASS && syntax->type != EBML_STOP)
 754         if ((res = ebml_read_num(matroska, pb, 8, &length)) < 0)
 755             return res;
 756
 757     switch (syntax->type) {
 758     case EBML_UINT:  res = ebml_read_uint  (pb, length, data);  break;
 759     case EBML_FLOAT: res = ebml_read_float (pb, length, data);  break;
 760     case EBML_STR:
 761     case EBML_UTF8:  res = ebml_read_ascii (pb, length, data);  break;
 762     case EBML_BIN:   res = ebml_read_binary(pb, length, data);  break;
 763     case EBML_NEST:  if ((res=ebml_read_master(matroska, length)) < 0)
 764                          return res;
 765                      if (id == MATROSKA_ID_SEGMENT)
 766                          matroska->segment_start = url_ftell(matroska->ctx->pb);
 767                      return ebml_parse_nest(matroska, syntax->def.n, data);
 768     case EBML_PASS:  return ebml_parse_id(matroska, syntax->def.n, id, data);
 769     case EBML_STOP:  *(int *)data = 1;      return 1;
 770     default:         return url_fseek(pb,length,SEEK_CUR)<0 ? AVERROR(EIO) : 0;
 771     }
 772     if (res == AVERROR_INVALIDDATA)
 773         av_log(matroska->ctx, AV_LOG_ERROR, "Invalid element\n");
 774     else if (res == AVERROR(EIO))
 775         av_log(matroska->ctx, AV_LOG_ERROR, "Read error\n");
 776     return res;
 777 }
 778
 779 static void ebml_free(EbmlSyntax *syntax, void *data)
 780 {
 781     int i, j;
 782     for (i=0; syntax[i].id; i++) {
 783         void *data_off = (char *)data + syntax[i].data_offset;
 784         switch (syntax[i].type) {
 785         case EBML_STR:
 786         case EBML_UTF8:  av_freep(data_off);                      break;
 787         case EBML_BIN:   av_freep(&((EbmlBin *)data_off)->data);  break;
 788         case EBML_NEST:
 789             if (syntax[i].list_elem_size) {
 790                 EbmlList *list = data_off;
 791                 char *ptr = list->elem;
 792                 for (j=0; j<list->nb_elem; j++, ptr+=syntax[i].list_elem_size)
 793                     ebml_free(syntax[i].def.n, ptr);
 794                 av_free(list->elem);
 795             } else
 796                 ebml_free(syntax[i].def.n, data_off);
 797         default:  break;
 798         }
 799     }
 800 }
 801
 802
 803 /*
 804  * Autodetecting...
 805  */
 806 static int matroska_probe(AVProbeData *p)
 807 {
 808     uint64_t total = 0;
 809     int len_mask = 0x80, size = 1, n = 1;
 810     static const char probe_data[] = "matroska";
 811
 812     /* EBML header? */
 813     if (AV_RB32(p->buf) != EBML_ID_HEADER)
 814         return 0;
 815
 816     /* length of header */
 817     total = p->buf[4];
 818     while (size <= 8 && !(total & len_mask)) {
 819         size++;
 820         len_mask >>= 1;
 821     }
 822     if (size > 8)
 823       return 0;
 824     total &= (len_mask - 1);
 825     while (n < size)
 826         total = (total << 8) | p->buf[4 + n++];
 827
 828     /* Does the probe data contain the whole header? */
 829     if (p->buf_size < 4 + size + total)
 830       return 0;
 831
 832     /* The header must contain the document type 'matroska'. For now,
 833      * we don't parse the whole header but simply check for the
 834      * availability of that array of characters inside the header.
 835      * Not fully fool-proof, but good enough. */
 836     for (n = 4+size; n <= 4+size+total-(sizeof(probe_data)-1); n++)
 837         if (!memcmp(p->buf+n, probe_data, sizeof(probe_data)-1))
 838             return AVPROBE_SCORE_MAX;
 839
 840     return 0;
 841 }
 842
 843 static MatroskaTrack *matroska_find_track_by_num(MatroskaDemuxContext *matroska,
 844                                                  int num)
 845 {
 846     MatroskaTrack *tracks = matroska->tracks.elem;
 847     int i;
 848
 849     for (i=0; i < matroska->tracks.nb_elem; i++)
 850         if (tracks[i].num == num)
 851             return &tracks[i];
 852
 853     av_log(matroska->ctx, AV_LOG_ERROR, "Invalid track number %d\n", num);
 854     return NULL;
 855 }
 856
 857 static int matroska_decode_buffer(uint8_t** buf, int* buf_size,
 858                                   MatroskaTrack *track)
 859 {
 860     MatroskaTrackEncoding *encodings = track->encodings.elem;
 861     uint8_t* data = *buf;
 862     int isize = *buf_size;
 863     uint8_t* pkt_data = NULL;
 864     int pkt_size = isize;
 865     int result = 0;
 866     int olen;
 867
 868     switch (encodings[0].compression.algo) {
 869     case MATROSKA_TRACK_ENCODING_COMP_HEADERSTRIP:
 870         return encodings[0].compression.settings.size;
 871     case MATROSKA_TRACK_ENCODING_COMP_LZO:
 872         do {
 873             olen = pkt_size *= 3;
 874             pkt_data = av_realloc(pkt_data,
 875                                   pkt_size+LZO_OUTPUT_PADDING);
 876             result = lzo1x_decode(pkt_data, &olen, data, &isize);
 877         } while (result==LZO_OUTPUT_FULL && pkt_size<10000000);
 878         if (result)
 879             goto failed;
 880         pkt_size -= olen;
 881         break;
 882 #if CONFIG_ZLIB
 883     case MATROSKA_TRACK_ENCODING_COMP_ZLIB: {
 884         z_stream zstream = {0};
 885         if (inflateInit(&zstream) != Z_OK)
 886             return -1;
 887         zstream.next_in = data;
 888         zstream.avail_in = isize;
 889         do {
 890             pkt_size *= 3;
 891             pkt_data = av_realloc(pkt_data, pkt_size);
 892             zstream.avail_out = pkt_size - zstream.total_out;
 893             zstream.next_out = pkt_data + zstream.total_out;
 894             result = inflate(&zstream, Z_NO_FLUSH);
 895         } while (result==Z_OK && pkt_size<10000000);
 896         pkt_size = zstream.total_out;
 897         inflateEnd(&zstream);
 898         if (result != Z_STREAM_END)
 899             goto failed;
 900         break;
 901     }
 902 #endif
 903 #if CONFIG_BZLIB
 904     case MATROSKA_TRACK_ENCODING_COMP_BZLIB: {
 905         bz_stream bzstream = {0};
 906         if (BZ2_bzDecompressInit(&bzstream, 0, 0) != BZ_OK)
 907             return -1;
 908         bzstream.next_in = data;
 909         bzstream.avail_in = isize;
 910         do {
 911             pkt_size *= 3;
 912             pkt_data = av_realloc(pkt_data, pkt_size);
 913             bzstream.avail_out = pkt_size - bzstream.total_out_lo32;
 914             bzstream.next_out = pkt_data + bzstream.total_out_lo32;
 915             result = BZ2_bzDecompress(&bzstream);
 916         } while (result==BZ_OK && pkt_size<10000000);
 917         pkt_size = bzstream.total_out_lo32;
 918         BZ2_bzDecompressEnd(&bzstream);
 919         if (result != BZ_STREAM_END)
 920             goto failed;
 921         break;
 922     }
 923 #endif
 924     default:
 925         return -1;
 926     }
 927
 928     *buf = pkt_data;
 929     *buf_size = pkt_size;
 930     return 0;
 931  failed:
 932     av_free(pkt_data);
 933     return -1;
 934 }
 935
 936 static void matroska_fix_ass_packet(MatroskaDemuxContext *matroska,
 937                                     AVPacket *pkt, uint64_t display_duration)
 938 {
 939     char *line, *layer, *ptr = pkt->data, *end = ptr+pkt->size;
 940     for (; *ptr!=',' && ptr<end-1; ptr++);
 941     if (*ptr == ',')
 942         layer = ++ptr;
 943     for (; *ptr!=',' && ptr<end-1; ptr++);
 944     if (*ptr == ',') {
 945         int64_t end_pts = pkt->pts + display_duration;
 946         int sc = matroska->time_scale * pkt->pts / 10000000;
 947         int ec = matroska->time_scale * end_pts  / 10000000;
 948         int sh, sm, ss, eh, em, es, len;
 949         sh = sc/360000;  sc -= 360000*sh;
 950         sm = sc/  6000;  sc -=   6000*sm;
 951         ss = sc/   100;  sc -=    100*ss;
 952         eh = ec/360000;  ec -= 360000*eh;
 953         em = ec/  6000;  ec -=   6000*em;
 954         es = ec/   100;  ec -=    100*es;
 955         *ptr++ = '\0';
 956         len = 50 + end-ptr + FF_INPUT_BUFFER_PADDING_SIZE;
 957         if (!(line = av_malloc(len)))
 958             return;
 959         snprintf(line,len,"Dialogue: %s,%d:%02d:%02d.%02d,%d:%02d:%02d.%02d,%s\r\n",
 960                  layer, sh, sm, ss, sc, eh, em, es, ec, ptr);
 961         av_free(pkt->data);
 962         pkt->data = line;
 963         pkt->size = strlen(line);
 964     }
 965 }
 966
 967 static void matroska_merge_packets(AVPacket *out, AVPacket *in)
 968 {
 969     out->data = av_realloc(out->data, out->size+in->size);
 970     memcpy(out->data+out->size, in->data, in->size);
 971     out->size += in->size;
 972     av_destruct_packet(in);
 973     av_free(in);
 974 }
 975
 976 static void matroska_convert_tags(AVFormatContext *s, EbmlList *list)
 977 {
 978     MatroskaTag *tags = list->elem;
 979     int i, j;
 980
 981     for (i=0; i < list->nb_elem; i++) {
 982         for (j=0; j < FF_ARRAY_ELEMS(metadata); j++){
 983             if (!strcmp(tags[i].name, metadata[j].name)) {
 984                 int *ptr = (int *)((char *)s + metadata[j].offset);
 985                 if (*ptr)  continue;
 986                 if (metadata[j].size > sizeof(int))
 987                     av_strlcpy((char *)ptr, tags[i].string, metadata[j].size);
 988                 else
 989                     *ptr = atoi(tags[i].string);
 990             }
 991         }
 992         if (tags[i].sub.nb_elem)
 993             matroska_convert_tags(s, &tags[i].sub);
 994     }
 995 }
 996
 997 static void matroska_execute_seekhead(MatroskaDemuxContext *matroska)
 998 {
 999     EbmlList *seekhead_list = &matroska->seekhead;
1000     MatroskaSeekhead *seekhead = seekhead_list->elem;
1001     uint32_t level_up = matroska->level_up;
1002     int64_t before_pos = url_ftell(matroska->ctx->pb);
1003     MatroskaLevel level;
1004     int i;
1005
1006     for (i=0; i<seekhead_list->nb_elem; i++) {
1007         int64_t offset = seekhead[i].pos + matroska->segment_start;
1008
1009         if (seekhead[i].pos <= before_pos
1010             || seekhead[i].id == MATROSKA_ID_SEEKHEAD
1011             || seekhead[i].id == MATROSKA_ID_CLUSTER)
1012             continue;
1013
1014         /* seek */
1015         if (url_fseek(matroska->ctx->pb, offset, SEEK_SET) != offset)
1016             continue;
1017
1018         /* We don't want to lose our seekhead level, so we add
1019          * a dummy. This is a crude hack. */
1020         if (matroska->num_levels == EBML_MAX_DEPTH) {
1021             av_log(matroska->ctx, AV_LOG_INFO,
1022                    "Max EBML element depth (%d) reached, "
1023                    "cannot parse further.\n", EBML_MAX_DEPTH);
1024             break;
1025         }
1026
1027         level.start = 0;
1028         level.length = (uint64_t)-1;
1029         matroska->levels[matroska->num_levels] = level;
1030         matroska->num_levels++;
1031
1032         ebml_parse(matroska, matroska_segment, matroska);
1033
1034         /* remove dummy level */
1035         while (matroska->num_levels) {
1036             uint64_t length = matroska->levels[--matroska->num_levels].length;
1037             if (length == (uint64_t)-1)
1038                 break;
1039         }
1040     }
1041
1042     /* seek back */
1043     url_fseek(matroska->ctx->pb, before_pos, SEEK_SET);
1044     matroska->level_up = level_up;
1045 }
1046
1047 static int matroska_aac_profile(char *codec_id)
1048 {
1049     static const char * const aac_profiles[] = { "MAIN", "LC", "SSR" };
1050     int profile;
1051
1052     for (profile=0; profile<FF_ARRAY_ELEMS(aac_profiles); profile++)
1053         if (strstr(codec_id, aac_profiles[profile]))
1054             break;
1055     return profile + 1;
1056 }
1057
1058 static int matroska_aac_sri(int samplerate)
1059 {
1060     int sri;
1061
1062     for (sri=0; sri<FF_ARRAY_ELEMS(ff_mpeg4audio_sample_rates); sri++)
1063         if (ff_mpeg4audio_sample_rates[sri] == samplerate)
1064             break;
1065     return sri;
1066 }
1067
1068 static int matroska_read_header(AVFormatContext *s, AVFormatParameters *ap)
1069 {
1070     MatroskaDemuxContext *matroska = s->priv_data;
1071     EbmlList *attachements_list = &matroska->attachments;
1072     MatroskaAttachement *attachements;
1073     EbmlList *chapters_list = &matroska->chapters;
1074     MatroskaChapter *chapters;
1075     MatroskaTrack *tracks;
1076     EbmlList *index_list;
1077     MatroskaIndex *index;
1078     int index_scale = 1;
1079     uint64_t max_start = 0;
1080     Ebml ebml = { 0 };
1081     AVStream *st;
1082     int i, j;
1083
1084     matroska->ctx = s;
1085
1086     /* First read the EBML header. */
1087     if (ebml_parse(matroska, ebml_syntax, &ebml)
1088         || ebml.version > EBML_VERSION       || ebml.max_size > sizeof(uint64_t)
1089         || ebml.id_length > sizeof(uint32_t) || strcmp(ebml.doctype, "matroska")
1090         || ebml.doctype_version > 2) {
1091         av_log(matroska->ctx, AV_LOG_ERROR,
1092                "EBML header using unsupported features\n"
1093                "(EBML version %"PRIu64", doctype %s, doc version %"PRIu64")\n",
1094                ebml.version, ebml.doctype, ebml.doctype_version);
1095         return AVERROR_NOFMT;
1096     }
1097     ebml_free(ebml_syntax, &ebml);
1098
1099     /* The next thing is a segment. */
1100     if (ebml_parse(matroska, matroska_segments, matroska) < 0)
1101         return -1;
1102     matroska_execute_seekhead(matroska);
1103
1104     if (matroska->duration)
1105         matroska->ctx->duration = matroska->duration * matroska->time_scale
1106                                   * 1000 / AV_TIME_BASE;
1107     if (matroska->title)
1108         strncpy(matroska->ctx->title, matroska->title,
1109                 sizeof(matroska->ctx->title)-1);
1110     matroska_convert_tags(s, &matroska->tags);
1111
1112     tracks = matroska->tracks.elem;
1113     for (i=0; i < matroska->tracks.nb_elem; i++) {
1114         MatroskaTrack *track = &tracks[i];
1115         enum CodecID codec_id = CODEC_ID_NONE;
1116         EbmlList *encodings_list = &tracks->encodings;
1117         MatroskaTrackEncoding *encodings = encodings_list->elem;
1118         uint8_t *extradata = NULL;
1119         int extradata_size = 0;
1120         int extradata_offset = 0;
1121         ByteIOContext b;
1122
1123         /* Apply some sanity checks. */
1124         if (track->type != MATROSKA_TRACK_TYPE_VIDEO &&
1125             track->type != MATROSKA_TRACK_TYPE_AUDIO &&
1126             track->type != MATROSKA_TRACK_TYPE_SUBTITLE) {
1127             av_log(matroska->ctx, AV_LOG_INFO,
1128                    "Unknown or unsupported track type %"PRIu64"\n",
1129                    track->type);
1130             continue;
1131         }
1132         if (track->codec_id == NULL)
1133             continue;
1134
1135         if (track->type == MATROSKA_TRACK_TYPE_VIDEO) {
1136             if (!track->default_duration)
1137                 track->default_duration = 1000000000/track->video.frame_rate;
1138             if (!track->video.display_width)
1139                 track->video.display_width = track->video.pixel_width;
1140             if (!track->video.display_height)
1141                 track->video.display_height = track->video.pixel_height;
1142         } else if (track->type == MATROSKA_TRACK_TYPE_AUDIO) {
1143             if (!track->audio.out_samplerate)
1144                 track->audio.out_samplerate = track->audio.samplerate;
1145         }
1146         if (encodings_list->nb_elem > 1) {
1147             av_log(matroska->ctx, AV_LOG_ERROR,
1148                    "Multiple combined encodings no supported");
1149         } else if (encodings_list->nb_elem == 1) {
1150             if (encodings[0].type ||
1151                 (encodings[0].compression.algo != MATROSKA_TRACK_ENCODING_COMP_HEADERSTRIP &&
1152 #if CONFIG_ZLIB
1153                  encodings[0].compression.algo != MATROSKA_TRACK_ENCODING_COMP_ZLIB &&
1154 #endif
1155 #if CONFIG_BZLIB
1156                  encodings[0].compression.algo != MATROSKA_TRACK_ENCODING_COMP_BZLIB &&
1157 #endif
1158                  encodings[0].compression.algo != MATROSKA_TRACK_ENCODING_COMP_LZO)) {
1159                 encodings[0].scope = 0;
1160                 av_log(matroska->ctx, AV_LOG_ERROR,
1161                        "Unsupported encoding type");
1162             } else if (track->codec_priv.size && encodings[0].scope&2) {
1163                 uint8_t *codec_priv = track->codec_priv.data;
1164                 int offset = matroska_decode_buffer(&track->codec_priv.data,
1165                                                     &track->codec_priv.size,
1166                                                     track);
1167                 if (offset < 0) {
1168                     track->codec_priv.data = NULL;
1169                     track->codec_priv.size = 0;
1170                     av_log(matroska->ctx, AV_LOG_ERROR,
1171                            "Failed to decode codec private data\n");
1172                 } else if (offset > 0) {
1173                     track->codec_priv.data = av_malloc(track->codec_priv.size + offset);
1174                     memcpy(track->codec_priv.data,
1175                            encodings[0].compression.settings.data, offset);
1176                     memcpy(track->codec_priv.data+offset, codec_priv,
1177                            track->codec_priv.size);
1178                     track->codec_priv.size += offset;
1179                 }
1180                 if (codec_priv != track->codec_priv.data)
1181                     av_free(codec_priv);
1182             }
1183         }
1184
1185         for(j=0; ff_mkv_codec_tags[j].id != CODEC_ID_NONE; j++){
1186             if(!strncmp(ff_mkv_codec_tags[j].str, track->codec_id,
1187                         strlen(ff_mkv_codec_tags[j].str))){
1188                 codec_id= ff_mkv_codec_tags[j].id;
1189                 break;
1190             }
1191         }
1192
1193         st = track->stream = av_new_stream(s, 0);
1194         if (st == NULL)
1195             return AVERROR(ENOMEM);
1196
1197         if (!strcmp(track->codec_id, "V_MS/VFW/FOURCC")
1198             && track->codec_priv.size >= 40
1199             && track->codec_priv.data != NULL) {
1200             track->video.fourcc = AV_RL32(track->codec_priv.data + 16);
1201             codec_id = codec_get_id(codec_bmp_tags, track->video.fourcc);
1202         } else if (!strcmp(track->codec_id, "A_MS/ACM")
1203                    && track->codec_priv.size >= 18
1204                    && track->codec_priv.data != NULL) {
1205             init_put_byte(&b, track->codec_priv.data, track->codec_priv.size,
1206                           URL_RDONLY, NULL, NULL, NULL, NULL);
1207             get_wav_header(&b, st->codec, track->codec_priv.size);
1208             codec_id = st->codec->codec_id;
1209             extradata_offset = 18;
1210             track->codec_priv.size -= extradata_offset;
1211         } else if (!strcmp(track->codec_id, "V_QUICKTIME")
1212                    && (track->codec_priv.size >= 86)
1213                    && (track->codec_priv.data != NULL)) {
1214             track->video.fourcc = AV_RL32(track->codec_priv.data);
1215             codec_id=codec_get_id(codec_movvideo_tags, track->video.fourcc);
1216         } else if (codec_id == CODEC_ID_PCM_S16BE) {
1217             switch (track->audio.bitdepth) {
1218             case  8:  codec_id = CODEC_ID_PCM_U8;     break;
1219             case 24:  codec_id = CODEC_ID_PCM_S24BE;  break;
1220             case 32:  codec_id = CODEC_ID_PCM_S32BE;  break;
1221             }
1222         } else if (codec_id == CODEC_ID_PCM_S16LE) {
1223             switch (track->audio.bitdepth) {
1224             case  8:  codec_id = CODEC_ID_PCM_U8;     break;
1225             case 24:  codec_id = CODEC_ID_PCM_S24LE;  break;
1226             case 32:  codec_id = CODEC_ID_PCM_S32LE;  break;
1227             }
1228         } else if (codec_id==CODEC_ID_PCM_F32LE && track->audio.bitdepth==64) {
1229             codec_id = CODEC_ID_PCM_F64LE;
1230         } else if (codec_id == CODEC_ID_AAC && !track->codec_priv.size) {
1231             int profile = matroska_aac_profile(track->codec_id);
1232             int sri = matroska_aac_sri(track->audio.samplerate);
1233             extradata = av_malloc(5);
1234             if (extradata == NULL)
1235                 return AVERROR(ENOMEM);
1236             extradata[0] = (profile << 3) | ((sri&0x0E) >> 1);
1237             extradata[1] = ((sri&0x01) << 7) | (track->audio.channels<<3);
1238             if (strstr(track->codec_id, "SBR")) {
1239                 sri = matroska_aac_sri(track->audio.out_samplerate);
1240                 extradata[2] = 0x56;
1241                 extradata[3] = 0xE5;
1242                 extradata[4] = 0x80 | (sri<<3);
1243                 extradata_size = 5;
1244             } else
1245                 extradata_size = 2;
1246         } else if (codec_id == CODEC_ID_TTA) {
1247             extradata_size = 30;
1248             extradata = av_mallocz(extradata_size);
1249             if (extradata == NULL)
1250                 return AVERROR(ENOMEM);
1251             init_put_byte(&b, extradata, extradata_size, 1,
1252                           NULL, NULL, NULL, NULL);
1253             put_buffer(&b, "TTA1", 4);
1254             put_le16(&b, 1);
1255             put_le16(&b, track->audio.channels);
1256             put_le16(&b, track->audio.bitdepth);
1257             put_le32(&b, track->audio.out_samplerate);
1258             put_le32(&b, matroska->ctx->duration * track->audio.out_samplerate);
1259         } else if (codec_id == CODEC_ID_RV10 || codec_id == CODEC_ID_RV20 ||
1260                    codec_id == CODEC_ID_RV30 || codec_id == CODEC_ID_RV40) {
1261             extradata_offset = 26;
1262             track->codec_priv.size -= extradata_offset;
1263         } else if (codec_id == CODEC_ID_RA_144) {
1264             track->audio.out_samplerate = 8000;
1265             track->audio.channels = 1;
1266         } else if (codec_id == CODEC_ID_RA_288 || codec_id == CODEC_ID_COOK ||
1267                    codec_id == CODEC_ID_ATRAC3) {
1268             init_put_byte(&b, track->codec_priv.data,track->codec_priv.size,
1269                           0, NULL, NULL, NULL, NULL);
1270             url_fskip(&b, 24);
1271             track->audio.coded_framesize = get_be32(&b);
1272             url_fskip(&b, 12);
1273             track->audio.sub_packet_h    = get_be16(&b);
1274             track->audio.frame_size      = get_be16(&b);
1275             track->audio.sub_packet_size = get_be16(&b);
1276             track->audio.buf = av_malloc(track->audio.frame_size * track->audio.sub_packet_h);
1277             if (codec_id == CODEC_ID_RA_288) {
1278                 st->codec->block_align = track->audio.coded_framesize;
1279                 track->codec_priv.size = 0;
1280             } else {
1281                 st->codec->block_align = track->audio.sub_packet_size;
1282                 extradata_offset = 78;
1283                 track->codec_priv.size -= extradata_offset;
1284             }
1285         }
1286
1287         if (codec_id == CODEC_ID_NONE)
1288             av_log(matroska->ctx, AV_LOG_INFO,
1289                    "Unknown/unsupported CodecID %s.\n", track->codec_id);
1290
1291         if (track->time_scale < 0.01)
1292             track->time_scale = 1.0;
1293         av_set_pts_info(st, 64, matroska->time_scale*track->time_scale, 1000*1000*1000); /* 64 bit pts in ns */
1294
1295         st->codec->codec_id = codec_id;
1296         st->start_time = 0;
1297         if (strcmp(track->language, "und"))
1298             av_strlcpy(st->language, track->language, 4);
1299
1300         if (track->flag_default)
1301             st->disposition |= AV_DISPOSITION_DEFAULT;
1302
1303         if (track->default_duration)
1304             av_reduce(&st->codec->time_base.num, &st->codec->time_base.den,
1305                       track->default_duration, 1000000000, 30000);
1306
1307         if(extradata){
1308             st->codec->extradata = extradata;
1309             st->codec->extradata_size = extradata_size;
1310         } else if(track->codec_priv.data && track->codec_priv.size > 0){
1311             st->codec->extradata = av_mallocz(track->codec_priv.size +
1312                                               FF_INPUT_BUFFER_PADDING_SIZE);
1313             if(st->codec->extradata == NULL)
1314                 return AVERROR(ENOMEM);
1315             st->codec->extradata_size = track->codec_priv.size;
1316             memcpy(st->codec->extradata,
1317                    track->codec_priv.data + extradata_offset,
1318                    track->codec_priv.size);
1319         }
1320
1321         if (track->type == MATROSKA_TRACK_TYPE_VIDEO) {
1322             st->codec->codec_type = CODEC_TYPE_VIDEO;
1323             st->codec->codec_tag  = track->video.fourcc;
1324             st->codec->width  = track->video.pixel_width;
1325             st->codec->height = track->video.pixel_height;
1326             av_reduce(&st->sample_aspect_ratio.num,
1327                       &st->sample_aspect_ratio.den,
1328                       st->codec->height * track->video.display_width,
1329                       st->codec-> width * track->video.display_height,
1330                       255);
1331             st->need_parsing = AVSTREAM_PARSE_HEADERS;
1332         } else if (track->type == MATROSKA_TRACK_TYPE_AUDIO) {
1333             st->codec->codec_type = CODEC_TYPE_AUDIO;
1334             st->codec->sample_rate = track->audio.out_samplerate;
1335             st->codec->channels = track->audio.channels;
1336         } else if (track->type == MATROSKA_TRACK_TYPE_SUBTITLE) {
1337             st->codec->codec_type = CODEC_TYPE_SUBTITLE;
1338         }
1339     }
1340
1341     attachements = attachements_list->elem;
1342     for (j=0; j<attachements_list->nb_elem; j++) {
1343         if (!(attachements[j].filename && attachements[j].mime &&
1344               attachements[j].bin.data && attachements[j].bin.size > 0)) {
1345             av_log(matroska->ctx, AV_LOG_ERROR, "incomplete attachment\n");
1346         } else {
1347             AVStream *st = av_new_stream(s, 0);
1348             if (st == NULL)
1349                 break;
1350             st->filename          = av_strdup(attachements[j].filename);
1351             st->codec->codec_id = CODEC_ID_NONE;
1352             st->codec->codec_type = CODEC_TYPE_ATTACHMENT;
1353             st->codec->extradata  = av_malloc(attachements[j].bin.size);
1354             if(st->codec->extradata == NULL)
1355                 break;
1356             st->codec->extradata_size = attachements[j].bin.size;
1357             memcpy(st->codec->extradata, attachements[j].bin.data, attachements[j].bin.size);
1358
1359             for (i=0; ff_mkv_mime_tags[i].id != CODEC_ID_NONE; i++) {
1360                 if (!strncmp(ff_mkv_mime_tags[i].str, attachements[j].mime,
1361                              strlen(ff_mkv_mime_tags[i].str))) {
1362                     st->codec->codec_id = ff_mkv_mime_tags[i].id;
1363                     break;
1364                 }
1365             }
1366         }
1367     }
1368
1369     chapters = chapters_list->elem;
1370     for (i=0; i<chapters_list->nb_elem; i++)
1371         if (chapters[i].start != AV_NOPTS_VALUE && chapters[i].uid
1372             && (max_start==0 || chapters[i].start > max_start)) {
1373             ff_new_chapter(s, chapters[i].uid, (AVRational){1, 1000000000},
1374                            chapters[i].start, chapters[i].end,
1375                            chapters[i].title);
1376             max_start = chapters[i].start;
1377         }
1378
1379     index_list = &matroska->index;
1380     index = index_list->elem;
1381     if (index_list->nb_elem
1382         && index[0].time > 100000000000000/matroska->time_scale) {
1383         av_log(matroska->ctx, AV_LOG_WARNING, "Working around broken index.\n");
1384         index_scale = matroska->time_scale;
1385     }
1386     for (i=0; i<index_list->nb_elem; i++) {
1387         EbmlList *pos_list = &index[i].pos;
1388         MatroskaIndexPos *pos = pos_list->elem;
1389         for (j=0; j<pos_list->nb_elem; j++) {
1390             MatroskaTrack *track = matroska_find_track_by_num(matroska,
1391                                                               pos[j].track);
1392             if (track && track->stream)
1393                 av_add_index_entry(track->stream,
1394                                    pos[j].pos + matroska->segment_start,
1395                                    index[i].time/index_scale, 0, 0,
1396                                    AVINDEX_KEYFRAME);
1397         }
1398     }
1399
1400     return 0;
1401 }
1402
1403 /*
1404  * Put one packet in an application-supplied AVPacket struct.
1405  * Returns 0 on success or -1 on failure.
1406  */
1407 static int matroska_deliver_packet(MatroskaDemuxContext *matroska,
1408                                    AVPacket *pkt)
1409 {
1410     if (matroska->num_packets > 0) {
1411         memcpy(pkt, matroska->packets[0], sizeof(AVPacket));
1412         av_free(matroska->packets[0]);
1413         if (matroska->num_packets > 1) {
1414             memmove(&matroska->packets[0], &matroska->packets[1],
1415                     (matroska->num_packets - 1) * sizeof(AVPacket *));
1416             matroska->packets =
1417                 av_realloc(matroska->packets, (matroska->num_packets - 1) *
1418                            sizeof(AVPacket *));
1419         } else {
1420             av_freep(&matroska->packets);
1421         }
1422         matroska->num_packets--;
1423         return 0;
1424     }
1425
1426     return -1;
1427 }
1428
1429 /*
1430  * Free all packets in our internal queue.
1431  */
1432 static void matroska_clear_queue(MatroskaDemuxContext *matroska)
1433 {
1434     if (matroska->packets) {
1435         int n;
1436         for (n = 0; n < matroska->num_packets; n++) {
1437             av_free_packet(matroska->packets[n]);
1438             av_free(matroska->packets[n]);
1439         }
1440         av_freep(&matroska->packets);
1441         matroska->num_packets = 0;
1442     }
1443 }
1444
1445 static int matroska_parse_block(MatroskaDemuxContext *matroska, uint8_t *data,
1446                                 int size, int64_t pos, uint64_t cluster_time,
1447                                 uint64_t duration, int is_keyframe,
1448                                 int64_t cluster_pos)
1449 {
1450     uint64_t timecode = AV_NOPTS_VALUE;
1451     MatroskaTrack *track;
1452     int res = 0;
1453     AVStream *st;
1454     AVPacket *pkt;
1455     int16_t block_time;
1456     uint32_t *lace_size = NULL;
1457     int n, flags, laces = 0;
1458     uint64_t num;
1459
1460     if ((n = matroska_ebmlnum_uint(matroska, data, size, &num)) < 0) {
1461         av_log(matroska->ctx, AV_LOG_ERROR, "EBML block data error\n");
1462         return res;
1463     }
1464     data += n;
1465     size -= n;
1466
1467     track = matroska_find_track_by_num(matroska, num);
1468     if (size <= 3 || !track || !track->stream) {
1469         av_log(matroska->ctx, AV_LOG_INFO,
1470                "Invalid stream %"PRIu64" or size %u\n", num, size);
1471         return res;
1472     }
1473     st = track->stream;
1474     if (st->discard >= AVDISCARD_ALL)
1475         return res;
1476     if (duration == AV_NOPTS_VALUE)
1477         duration = track->default_duration / matroska->time_scale;
1478
1479     block_time = AV_RB16(data);
1480     data += 2;
1481     flags = *data++;
1482     size -= 3;
1483     if (is_keyframe == -1)
1484         is_keyframe = flags & 0x80 ? PKT_FLAG_KEY : 0;
1485
1486     if (cluster_time != (uint64_t)-1
1487         && (block_time >= 0 || cluster_time >= -block_time)) {
1488         timecode = cluster_time + block_time;
1489         if (track->type == MATROSKA_TRACK_TYPE_SUBTITLE
1490             && timecode < track->end_timecode)
1491             is_keyframe = 0;  /* overlapping subtitles are not key frame */
1492         if (is_keyframe)
1493             av_add_index_entry(st, cluster_pos, timecode, 0,0,AVINDEX_KEYFRAME);
1494         track->end_timecode = FFMAX(track->end_timecode, timecode+duration);
1495     }
1496
1497     if (matroska->skip_to_keyframe && track->type != MATROSKA_TRACK_TYPE_SUBTITLE) {
1498         if (!is_keyframe || timecode < matroska->skip_to_timecode)
1499             return res;
1500         matroska->skip_to_keyframe = 0;
1501     }
1502
1503     switch ((flags & 0x06) >> 1) {
1504         case 0x0: /* no lacing */
1505             laces = 1;
1506             lace_size = av_mallocz(sizeof(int));
1507             lace_size[0] = size;
1508             break;
1509
1510         case 0x1: /* Xiph lacing */
1511         case 0x2: /* fixed-size lacing */
1512         case 0x3: /* EBML lacing */
1513             assert(size>0); // size <=3 is checked before size-=3 above
1514             laces = (*data) + 1;
1515             data += 1;
1516             size -= 1;
1517             lace_size = av_mallocz(laces * sizeof(int));
1518
1519             switch ((flags & 0x06) >> 1) {
1520                 case 0x1: /* Xiph lacing */ {
1521                     uint8_t temp;
1522                     uint32_t total = 0;
1523                     for (n = 0; res == 0 && n < laces - 1; n++) {
1524                         while (1) {
1525                             if (size == 0) {
1526                                 res = -1;
1527                                 break;
1528                             }
1529                             temp = *data;
1530                             lace_size[n] += temp;
1531                             data += 1;
1532                             size -= 1;
1533                             if (temp != 0xff)
1534                                 break;
1535                         }
1536                         total += lace_size[n];
1537                     }
1538                     lace_size[n] = size - total;
1539                     break;
1540                 }
1541
1542                 case 0x2: /* fixed-size lacing */
1543                     for (n = 0; n < laces; n++)
1544                         lace_size[n] = size / laces;
1545                     break;
1546
1547                 case 0x3: /* EBML lacing */ {
1548                     uint32_t total;
1549                     n = matroska_ebmlnum_uint(matroska, data, size, &num);
1550                     if (n < 0) {
1551                         av_log(matroska->ctx, AV_LOG_INFO,
1552                                "EBML block data error\n");
1553                         break;
1554                     }
1555                     data += n;
1556                     size -= n;
1557                     total = lace_size[0] = num;
1558                     for (n = 1; res == 0 && n < laces - 1; n++) {
1559                         int64_t snum;
1560                         int r;
1561                         r = matroska_ebmlnum_sint(matroska, data, size, &snum);
1562                         if (r < 0) {
1563                             av_log(matroska->ctx, AV_LOG_INFO,
1564                                    "EBML block data error\n");
1565                             break;
1566                         }
1567                         data += r;
1568                         size -= r;
1569                         lace_size[n] = lace_size[n - 1] + snum;
1570                         total += lace_size[n];
1571                     }
1572                     lace_size[n] = size - total;
1573                     break;
1574                 }
1575             }
1576             break;
1577     }
1578
1579     if (res == 0) {
1580         for (n = 0; n < laces; n++) {
1581             if (st->codec->codec_id == CODEC_ID_RA_288 ||
1582                 st->codec->codec_id == CODEC_ID_COOK ||
1583                 st->codec->codec_id == CODEC_ID_ATRAC3) {
1584                 int a = st->codec->block_align;
1585                 int sps = track->audio.sub_packet_size;
1586                 int cfs = track->audio.coded_framesize;
1587                 int h = track->audio.sub_packet_h;
1588                 int y = track->audio.sub_packet_cnt;
1589                 int w = track->audio.frame_size;
1590                 int x;
1591
1592                 if (!track->audio.pkt_cnt) {
1593                     if (st->codec->codec_id == CODEC_ID_RA_288)
1594                         for (x=0; x<h/2; x++)
1595                             memcpy(track->audio.buf+x*2*w+y*cfs,
1596                                    data+x*cfs, cfs);
1597                     else
1598                         for (x=0; x<w/sps; x++)
1599                             memcpy(track->audio.buf+sps*(h*x+((h+1)/2)*(y&1)+(y>>1)), data+x*sps, sps);
1600
1601                     if (++track->audio.sub_packet_cnt >= h) {
1602                         track->audio.sub_packet_cnt = 0;
1603                         track->audio.pkt_cnt = h*w / a;
1604                     }
1605                 }
1606                 while (track->audio.pkt_cnt) {
1607                     pkt = av_mallocz(sizeof(AVPacket));
1608                     av_new_packet(pkt, a);
1609                     memcpy(pkt->data, track->audio.buf
1610                            + a * (h*w / a - track->audio.pkt_cnt--), a);
1611                     pkt->pos = pos;
1612                     pkt->stream_index = st->index;
1613                     dynarray_add(&matroska->packets,&matroska->num_packets,pkt);
1614                 }
1615             } else {
1616                 MatroskaTrackEncoding *encodings = track->encodings.elem;
1617                 int offset = 0, pkt_size = lace_size[n];
1618                 uint8_t *pkt_data = data;
1619
1620                 if (encodings && encodings->scope & 1) {
1621                     offset = matroska_decode_buffer(&pkt_data,&pkt_size, track);
1622                     if (offset < 0)
1623                         continue;
1624                 }
1625
1626                 pkt = av_mallocz(sizeof(AVPacket));
1627                 /* XXX: prevent data copy... */
1628                 if (av_new_packet(pkt, pkt_size+offset) < 0) {
1629                     av_free(pkt);
1630                     res = AVERROR(ENOMEM);
1631                     n = laces-1;
1632                     break;
1633                 }
1634                 if (offset)
1635                     memcpy (pkt->data, encodings->compression.settings.data, offset);
1636                 memcpy (pkt->data+offset, pkt_data, pkt_size);
1637
1638                 if (pkt_data != data)
1639                     av_free(pkt_data);
1640
1641                 if (n == 0)
1642                     pkt->flags = is_keyframe;
1643                 pkt->stream_index = st->index;
1644
1645                 pkt->pts = timecode;
1646                 pkt->pos = pos;
1647                 if (st->codec->codec_id == CODEC_ID_TEXT)
1648                     pkt->convergence_duration = duration;
1649                 else if (track->type != MATROSKA_TRACK_TYPE_SUBTITLE)
1650                     pkt->duration = duration;
1651
1652                 if (st->codec->codec_id == CODEC_ID_SSA)
1653                     matroska_fix_ass_packet(matroska, pkt, duration);
1654
1655                 if (matroska->prev_pkt &&
1656                     timecode != AV_NOPTS_VALUE &&
1657                     matroska->prev_pkt->pts == timecode &&
1658                     matroska->prev_pkt->stream_index == st->index)
1659                     matroska_merge_packets(matroska->prev_pkt, pkt);
1660                 else {
1661                     dynarray_add(&matroska->packets,&matroska->num_packets,pkt);
1662                     matroska->prev_pkt = pkt;
1663                 }
1664             }
1665
1666             if (timecode != AV_NOPTS_VALUE)
1667                 timecode = duration ? timecode + duration : AV_NOPTS_VALUE;
1668             data += lace_size[n];
1669         }
1670     }
1671
1672     av_free(lace_size);
1673     return res;
1674 }
1675
1676 static int matroska_parse_cluster(MatroskaDemuxContext *matroska)
1677 {
1678     MatroskaCluster cluster = { 0 };
1679     EbmlList *blocks_list;
1680     MatroskaBlock *blocks;
1681     int i, res;
1682     int64_t pos = url_ftell(matroska->ctx->pb);
1683     matroska->prev_pkt = NULL;
1684     if (matroska->has_cluster_id){
1685         /* For the first cluster we parse, its ID was already read as
1686            part of matroska_read_header(), so don't read it again */
1687         res = ebml_parse_id(matroska, matroska_clusters,
1688                             MATROSKA_ID_CLUSTER, &cluster);
1689         pos -= 4;  /* sizeof the ID which was already read */
1690         matroska->has_cluster_id = 0;
1691     } else
1692         res = ebml_parse(matroska, matroska_clusters, &cluster);
1693     blocks_list = &cluster.blocks;
1694     blocks = blocks_list->elem;
1695     for (i=0; i<blocks_list->nb_elem; i++)
1696         if (blocks[i].bin.size > 0)
1697             res=matroska_parse_block(matroska,
1698                                      blocks[i].bin.data, blocks[i].bin.size,
1699                                      blocks[i].bin.pos,  cluster.timecode,
1700                                      blocks[i].duration, !blocks[i].reference,
1701                                      pos);
1702     ebml_free(matroska_cluster, &cluster);
1703     if (res < 0)  matroska->done = 1;
1704     return res;
1705 }
1706
1707 static int matroska_read_packet(AVFormatContext *s, AVPacket *pkt)
1708 {
1709     MatroskaDemuxContext *matroska = s->priv_data;
1710
1711     while (matroska_deliver_packet(matroska, pkt)) {
1712         if (matroska->done)
1713             return AVERROR(EIO);
1714         matroska_parse_cluster(matroska);
1715     }
1716
1717     return 0;
1718 }
1719
1720 static int matroska_read_seek(AVFormatContext *s, int stream_index,
1721                               int64_t timestamp, int flags)
1722 {
1723     MatroskaDemuxContext *matroska = s->priv_data;
1724     MatroskaTrack *tracks = matroska->tracks.elem;
1725     AVStream *st = s->streams[stream_index];
1726     int i, index, index_sub, index_min;
1727
1728     if (!st->nb_index_entries)
1729         return 0;
1730     timestamp = FFMAX(timestamp, st->index_entries[0].timestamp);
1731
1732     if ((index = av_index_search_timestamp(st, timestamp, flags)) < 0) {
1733         url_fseek(s->pb, st->index_entries[st->nb_index_entries-1].pos, SEEK_SET);
1734         while ((index = av_index_search_timestamp(st, timestamp, flags)) < 0) {
1735             matroska_clear_queue(matroska);
1736             if (matroska_parse_cluster(matroska) < 0)
1737                 break;
1738         }
1739     }
1740
1741     matroska_clear_queue(matroska);
1742     if (index < 0)
1743         return 0;
1744
1745     index_min = index;
1746     for (i=0; i < matroska->tracks.nb_elem; i++) {
1747         tracks[i].end_timecode = 0;
1748         if (tracks[i].type == MATROSKA_TRACK_TYPE_SUBTITLE
1749             && !tracks[i].stream->discard != AVDISCARD_ALL) {
1750             index_sub = av_index_search_timestamp(tracks[i].stream, st->index_entries[index].timestamp, AVSEEK_FLAG_BACKWARD);
1751             if (index_sub >= 0
1752                 && st->index_entries[index_sub].pos < st->index_entries[index_min].pos
1753                 && st->index_entries[index].timestamp - st->index_entries[index_sub].timestamp < 30000000000/matroska->time_scale)
1754                 index_min = index_sub;
1755         }
1756     }
1757
1758     url_fseek(s->pb, st->index_entries[index_min].pos, SEEK_SET);
1759     matroska->skip_to_keyframe = !(flags & AVSEEK_FLAG_ANY);
1760     matroska->skip_to_timecode = st->index_entries[index].timestamp;
1761     matroska->done = 0;
1762     av_update_cur_dts(s, st, st->index_entries[index].timestamp);
1763     return 0;
1764 }
1765
1766 static int matroska_read_close(AVFormatContext *s)
1767 {
1768     MatroskaDemuxContext *matroska = s->priv_data;
1769     MatroskaTrack *tracks = matroska->tracks.elem;
1770     int n;
1771
1772     matroska_clear_queue(matroska);
1773
1774     for (n=0; n < matroska->tracks.nb_elem; n++)
1775         if (tracks[n].type == MATROSKA_TRACK_TYPE_AUDIO)
1776             av_free(tracks[n].audio.buf);
1777     ebml_free(matroska_segment, matroska);
1778
1779     return 0;
1780 }
1781
1782 AVInputFormat matroska_demuxer = {
1783     "matroska",
1784     NULL_IF_CONFIG_SMALL("Matroska file format"),
1785     sizeof(MatroskaDemuxContext),
1786     matroska_probe,
1787     matroska_read_header,
1788     matroska_read_packet,
1789     matroska_read_close,
1790     matroska_read_seek,
1791 };