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
  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 #include "internal.h"
  34 /* For ff_codec_get_id(). */
  35 #include "riff.h"
  36 #include "isom.h"
  37 #include "rm.h"
  38 #include "matroska.h"
  39 #include "libavcodec/mpeg4audio.h"
  40 #include "libavutil/intfloat_readwrite.h"
  41 #include "libavutil/intreadwrite.h"
  42 #include "libavutil/avstring.h"
  43 #include "libavutil/lzo.h"
  44 #if CONFIG_ZLIB
  45 #include <zlib.h>
  46 #endif
  47 #if CONFIG_BZLIB
  48 #include <bzlib.h>
  49 #endif
  50
  51 typedef enum {
  52     EBML_NONE,
  53     EBML_UINT,
  54     EBML_FLOAT,
  55     EBML_STR,
  56     EBML_UTF8,
  57     EBML_BIN,
  58     EBML_NEST,
  59     EBML_PASS,
  60     EBML_STOP,
  61 } EbmlType;
  62
  63 typedef const struct EbmlSyntax {
  64     uint32_t id;
  65     EbmlType type;
  66     int list_elem_size;
  67     int data_offset;
  68     union {
  69         uint64_t    u;
  70         double      f;
  71         const char *s;
  72         const struct EbmlSyntax *n;
  73     } def;
  74 } EbmlSyntax;
  75
  76 typedef struct {
  77     int nb_elem;
  78     void *elem;
  79 } EbmlList;
  80
  81 typedef struct {
  82     int      size;
  83     uint8_t *data;
  84     int64_t  pos;
  85 } EbmlBin;
  86
  87 typedef struct {
  88     uint64_t version;
  89     uint64_t max_size;
  90     uint64_t id_length;
  91     char    *doctype;
  92     uint64_t doctype_version;
  93 } Ebml;
  94
  95 typedef struct {
  96     uint64_t algo;
  97     EbmlBin  settings;
  98 } MatroskaTrackCompression;
  99
 100 typedef struct {
 101     uint64_t scope;
 102     uint64_t type;
 103     MatroskaTrackCompression compression;
 104 } MatroskaTrackEncoding;
 105
 106 typedef struct {
 107     double   frame_rate;
 108     uint64_t display_width;
 109     uint64_t display_height;
 110     uint64_t pixel_width;
 111     uint64_t pixel_height;
 112     uint64_t fourcc;
 113 } MatroskaTrackVideo;
 114
 115 typedef struct {
 116     double   samplerate;
 117     double   out_samplerate;
 118     uint64_t bitdepth;
 119     uint64_t channels;
 120
 121     /* real audio header (extracted from extradata) */
 122     int      coded_framesize;
 123     int      sub_packet_h;
 124     int      frame_size;
 125     int      sub_packet_size;
 126     int      sub_packet_cnt;
 127     int      pkt_cnt;
 128     uint8_t *buf;
 129 } MatroskaTrackAudio;
 130
 131 typedef struct {
 132     uint64_t num;
 133     uint64_t uid;
 134     uint64_t type;
 135     char    *name;
 136     char    *codec_id;
 137     EbmlBin  codec_priv;
 138     char    *language;
 139     double time_scale;
 140     uint64_t default_duration;
 141     uint64_t flag_default;
 142     uint64_t flag_forced;
 143     MatroskaTrackVideo video;
 144     MatroskaTrackAudio audio;
 145     EbmlList encodings;
 146
 147     AVStream *stream;
 148     int64_t end_timecode;
 149     int ms_compat;
 150 } MatroskaTrack;
 151
 152 typedef struct {
 153     uint64_t uid;
 154     char *filename;
 155     char *mime;
 156     EbmlBin bin;
 157
 158     AVStream *stream;
 159 } MatroskaAttachement;
 160
 161 typedef struct {
 162     uint64_t start;
 163     uint64_t end;
 164     uint64_t uid;
 165     char    *title;
 166
 167     AVChapter *chapter;
 168 } MatroskaChapter;
 169
 170 typedef struct {
 171     uint64_t track;
 172     uint64_t pos;
 173 } MatroskaIndexPos;
 174
 175 typedef struct {
 176     uint64_t time;
 177     EbmlList pos;
 178 } MatroskaIndex;
 179
 180 typedef struct {
 181     char *name;
 182     char *string;
 183     char *lang;
 184     uint64_t def;
 185     EbmlList sub;
 186 } MatroskaTag;
 187
 188 typedef struct {
 189     char    *type;
 190     uint64_t typevalue;
 191     uint64_t trackuid;
 192     uint64_t chapteruid;
 193     uint64_t attachuid;
 194 } MatroskaTagTarget;
 195
 196 typedef struct {
 197     MatroskaTagTarget target;
 198     EbmlList tag;
 199 } MatroskaTags;
 200
 201 typedef struct {
 202     uint64_t id;
 203     uint64_t pos;
 204 } MatroskaSeekhead;
 205
 206 typedef struct {
 207     uint64_t start;
 208     uint64_t length;
 209 } MatroskaLevel;
 210
 211 typedef struct {
 212     AVFormatContext *ctx;
 213
 214     /* EBML stuff */
 215     int num_levels;
 216     MatroskaLevel levels[EBML_MAX_DEPTH];
 217     int level_up;
 218     uint32_t current_id;
 219
 220     uint64_t time_scale;
 221     double   duration;
 222     char    *title;
 223     EbmlList tracks;
 224     EbmlList attachments;
 225     EbmlList chapters;
 226     EbmlList index;
 227     EbmlList tags;
 228     EbmlList seekhead;
 229
 230     /* byte position of the segment inside the stream */
 231     int64_t segment_start;
 232
 233     /* the packet queue */
 234     AVPacket **packets;
 235     int num_packets;
 236     AVPacket *prev_pkt;
 237
 238     int done;
 239
 240     /* What to skip before effectively reading a packet. */
 241     int skip_to_keyframe;
 242     uint64_t skip_to_timecode;
 243 } MatroskaDemuxContext;
 244
 245 typedef struct {
 246     uint64_t duration;
 247     int64_t  reference;
 248     uint64_t non_simple;
 249     EbmlBin  bin;
 250 } MatroskaBlock;
 251
 252 typedef struct {
 253     uint64_t timecode;
 254     EbmlList blocks;
 255 } MatroskaCluster;
 256
 257 static EbmlSyntax ebml_header[] = {
 258     { EBML_ID_EBMLREADVERSION,        EBML_UINT, 0, offsetof(Ebml,version), {.u=EBML_VERSION} },
 259     { EBML_ID_EBMLMAXSIZELENGTH,      EBML_UINT, 0, offsetof(Ebml,max_size), {.u=8} },
 260     { EBML_ID_EBMLMAXIDLENGTH,        EBML_UINT, 0, offsetof(Ebml,id_length), {.u=4} },
 261     { EBML_ID_DOCTYPE,                EBML_STR,  0, offsetof(Ebml,doctype), {.s="(none)"} },
 262     { EBML_ID_DOCTYPEREADVERSION,     EBML_UINT, 0, offsetof(Ebml,doctype_version), {.u=1} },
 263     { EBML_ID_EBMLVERSION,            EBML_NONE },
 264     { EBML_ID_DOCTYPEVERSION,         EBML_NONE },
 265     { 0 }
 266 };
 267
 268 static EbmlSyntax ebml_syntax[] = {
 269     { EBML_ID_HEADER,                 EBML_NEST, 0, 0, {.n=ebml_header} },
 270     { 0 }
 271 };
 272
 273 static EbmlSyntax matroska_info[] = {
 274     { MATROSKA_ID_TIMECODESCALE,      EBML_UINT,  0, offsetof(MatroskaDemuxContext,time_scale), {.u=1000000} },
 275     { MATROSKA_ID_DURATION,           EBML_FLOAT, 0, offsetof(MatroskaDemuxContext,duration) },
 276     { MATROSKA_ID_TITLE,              EBML_UTF8,  0, offsetof(MatroskaDemuxContext,title) },
 277     { MATROSKA_ID_WRITINGAPP,         EBML_NONE },
 278     { MATROSKA_ID_MUXINGAPP,          EBML_NONE },
 279     { MATROSKA_ID_DATEUTC,            EBML_NONE },
 280     { MATROSKA_ID_SEGMENTUID,         EBML_NONE },
 281     { 0 }
 282 };
 283
 284 static EbmlSyntax matroska_track_video[] = {
 285     { MATROSKA_ID_VIDEOFRAMERATE,     EBML_FLOAT,0, offsetof(MatroskaTrackVideo,frame_rate) },
 286     { MATROSKA_ID_VIDEODISPLAYWIDTH,  EBML_UINT, 0, offsetof(MatroskaTrackVideo,display_width) },
 287     { MATROSKA_ID_VIDEODISPLAYHEIGHT, EBML_UINT, 0, offsetof(MatroskaTrackVideo,display_height) },
 288     { MATROSKA_ID_VIDEOPIXELWIDTH,    EBML_UINT, 0, offsetof(MatroskaTrackVideo,pixel_width) },
 289     { MATROSKA_ID_VIDEOPIXELHEIGHT,   EBML_UINT, 0, offsetof(MatroskaTrackVideo,pixel_height) },
 290     { MATROSKA_ID_VIDEOCOLORSPACE,    EBML_UINT, 0, offsetof(MatroskaTrackVideo,fourcc) },
 291     { MATROSKA_ID_VIDEOPIXELCROPB,    EBML_NONE },
 292     { MATROSKA_ID_VIDEOPIXELCROPT,    EBML_NONE },
 293     { MATROSKA_ID_VIDEOPIXELCROPL,    EBML_NONE },
 294     { MATROSKA_ID_VIDEOPIXELCROPR,    EBML_NONE },
 295     { MATROSKA_ID_VIDEODISPLAYUNIT,   EBML_NONE },
 296     { MATROSKA_ID_VIDEOFLAGINTERLACED,EBML_NONE },
 297     { MATROSKA_ID_VIDEOSTEREOMODE,    EBML_NONE },
 298     { MATROSKA_ID_VIDEOASPECTRATIO,   EBML_NONE },
 299     { 0 }
 300 };
 301
 302 static EbmlSyntax matroska_track_audio[] = {
 303     { MATROSKA_ID_AUDIOSAMPLINGFREQ,  EBML_FLOAT,0, offsetof(MatroskaTrackAudio,samplerate), {.f=8000.0} },
 304     { MATROSKA_ID_AUDIOOUTSAMPLINGFREQ,EBML_FLOAT,0,offsetof(MatroskaTrackAudio,out_samplerate) },
 305     { MATROSKA_ID_AUDIOBITDEPTH,      EBML_UINT, 0, offsetof(MatroskaTrackAudio,bitdepth) },
 306     { MATROSKA_ID_AUDIOCHANNELS,      EBML_UINT, 0, offsetof(MatroskaTrackAudio,channels), {.u=1} },
 307     { 0 }
 308 };
 309
 310 static EbmlSyntax matroska_track_encoding_compression[] = {
 311     { MATROSKA_ID_ENCODINGCOMPALGO,   EBML_UINT, 0, offsetof(MatroskaTrackCompression,algo), {.u=0} },
 312     { MATROSKA_ID_ENCODINGCOMPSETTINGS,EBML_BIN, 0, offsetof(MatroskaTrackCompression,settings) },
 313     { 0 }
 314 };
 315
 316 static EbmlSyntax matroska_track_encoding[] = {
 317     { MATROSKA_ID_ENCODINGSCOPE,      EBML_UINT, 0, offsetof(MatroskaTrackEncoding,scope), {.u=1} },
 318     { MATROSKA_ID_ENCODINGTYPE,       EBML_UINT, 0, offsetof(MatroskaTrackEncoding,type), {.u=0} },
 319     { MATROSKA_ID_ENCODINGCOMPRESSION,EBML_NEST, 0, offsetof(MatroskaTrackEncoding,compression), {.n=matroska_track_encoding_compression} },
 320     { MATROSKA_ID_ENCODINGORDER,      EBML_NONE },
 321     { 0 }
 322 };
 323
 324 static EbmlSyntax matroska_track_encodings[] = {
 325     { MATROSKA_ID_TRACKCONTENTENCODING, EBML_NEST, sizeof(MatroskaTrackEncoding), offsetof(MatroskaTrack,encodings), {.n=matroska_track_encoding} },
 326     { 0 }
 327 };
 328
 329 static EbmlSyntax matroska_track[] = {
 330     { MATROSKA_ID_TRACKNUMBER,          EBML_UINT, 0, offsetof(MatroskaTrack,num) },
 331     { MATROSKA_ID_TRACKNAME,            EBML_UTF8, 0, offsetof(MatroskaTrack,name) },
 332     { MATROSKA_ID_TRACKUID,             EBML_UINT, 0, offsetof(MatroskaTrack,uid) },
 333     { MATROSKA_ID_TRACKTYPE,            EBML_UINT, 0, offsetof(MatroskaTrack,type) },
 334     { MATROSKA_ID_CODECID,              EBML_STR,  0, offsetof(MatroskaTrack,codec_id) },
 335     { MATROSKA_ID_CODECPRIVATE,         EBML_BIN,  0, offsetof(MatroskaTrack,codec_priv) },
 336     { MATROSKA_ID_TRACKLANGUAGE,        EBML_UTF8, 0, offsetof(MatroskaTrack,language), {.s="eng"} },
 337     { MATROSKA_ID_TRACKDEFAULTDURATION, EBML_UINT, 0, offsetof(MatroskaTrack,default_duration) },
 338     { MATROSKA_ID_TRACKTIMECODESCALE,   EBML_FLOAT,0, offsetof(MatroskaTrack,time_scale), {.f=1.0} },
 339     { MATROSKA_ID_TRACKFLAGDEFAULT,     EBML_UINT, 0, offsetof(MatroskaTrack,flag_default), {.u=1} },
 340     { MATROSKA_ID_TRACKFLAGFORCED,      EBML_UINT, 0, offsetof(MatroskaTrack,flag_forced), {.u=0} },
 341     { MATROSKA_ID_TRACKVIDEO,           EBML_NEST, 0, offsetof(MatroskaTrack,video), {.n=matroska_track_video} },
 342     { MATROSKA_ID_TRACKAUDIO,           EBML_NEST, 0, offsetof(MatroskaTrack,audio), {.n=matroska_track_audio} },
 343     { MATROSKA_ID_TRACKCONTENTENCODINGS,EBML_NEST, 0, 0, {.n=matroska_track_encodings} },
 344     { MATROSKA_ID_TRACKFLAGENABLED,     EBML_NONE },
 345     { MATROSKA_ID_TRACKFLAGLACING,      EBML_NONE },
 346     { MATROSKA_ID_CODECNAME,            EBML_NONE },
 347     { MATROSKA_ID_CODECDECODEALL,       EBML_NONE },
 348     { MATROSKA_ID_CODECINFOURL,         EBML_NONE },
 349     { MATROSKA_ID_CODECDOWNLOADURL,     EBML_NONE },
 350     { MATROSKA_ID_TRACKMINCACHE,        EBML_NONE },
 351     { MATROSKA_ID_TRACKMAXCACHE,        EBML_NONE },
 352     { MATROSKA_ID_TRACKMAXBLKADDID,     EBML_NONE },
 353     { 0 }
 354 };
 355
 356 static EbmlSyntax matroska_tracks[] = {
 357     { MATROSKA_ID_TRACKENTRY,         EBML_NEST, sizeof(MatroskaTrack), offsetof(MatroskaDemuxContext,tracks), {.n=matroska_track} },
 358     { 0 }
 359 };
 360
 361 static EbmlSyntax matroska_attachment[] = {
 362     { MATROSKA_ID_FILEUID,            EBML_UINT, 0, offsetof(MatroskaAttachement,uid) },
 363     { MATROSKA_ID_FILENAME,           EBML_UTF8, 0, offsetof(MatroskaAttachement,filename) },
 364     { MATROSKA_ID_FILEMIMETYPE,       EBML_STR,  0, offsetof(MatroskaAttachement,mime) },
 365     { MATROSKA_ID_FILEDATA,           EBML_BIN,  0, offsetof(MatroskaAttachement,bin) },
 366     { MATROSKA_ID_FILEDESC,           EBML_NONE },
 367     { 0 }
 368 };
 369
 370 static EbmlSyntax matroska_attachments[] = {
 371     { MATROSKA_ID_ATTACHEDFILE,       EBML_NEST, sizeof(MatroskaAttachement), offsetof(MatroskaDemuxContext,attachments), {.n=matroska_attachment} },
 372     { 0 }
 373 };
 374
 375 static EbmlSyntax matroska_chapter_display[] = {
 376     { MATROSKA_ID_CHAPSTRING,         EBML_UTF8, 0, offsetof(MatroskaChapter,title) },
 377     { MATROSKA_ID_CHAPLANG,           EBML_NONE },
 378     { 0 }
 379 };
 380
 381 static EbmlSyntax matroska_chapter_entry[] = {
 382     { MATROSKA_ID_CHAPTERTIMESTART,   EBML_UINT, 0, offsetof(MatroskaChapter,start), {.u=AV_NOPTS_VALUE} },
 383     { MATROSKA_ID_CHAPTERTIMEEND,     EBML_UINT, 0, offsetof(MatroskaChapter,end), {.u=AV_NOPTS_VALUE} },
 384     { MATROSKA_ID_CHAPTERUID,         EBML_UINT, 0, offsetof(MatroskaChapter,uid) },
 385     { MATROSKA_ID_CHAPTERDISPLAY,     EBML_NEST, 0, 0, {.n=matroska_chapter_display} },
 386     { MATROSKA_ID_CHAPTERFLAGHIDDEN,  EBML_NONE },
 387     { MATROSKA_ID_CHAPTERFLAGENABLED, EBML_NONE },
 388     { MATROSKA_ID_CHAPTERPHYSEQUIV,   EBML_NONE },
 389     { MATROSKA_ID_CHAPTERATOM,        EBML_NONE },
 390     { 0 }
 391 };
 392
 393 static EbmlSyntax matroska_chapter[] = {
 394     { MATROSKA_ID_CHAPTERATOM,        EBML_NEST, sizeof(MatroskaChapter), offsetof(MatroskaDemuxContext,chapters), {.n=matroska_chapter_entry} },
 395     { MATROSKA_ID_EDITIONUID,         EBML_NONE },
 396     { MATROSKA_ID_EDITIONFLAGHIDDEN,  EBML_NONE },
 397     { MATROSKA_ID_EDITIONFLAGDEFAULT, EBML_NONE },
 398     { MATROSKA_ID_EDITIONFLAGORDERED, EBML_NONE },
 399     { 0 }
 400 };
 401
 402 static EbmlSyntax matroska_chapters[] = {
 403     { MATROSKA_ID_EDITIONENTRY,       EBML_NEST, 0, 0, {.n=matroska_chapter} },
 404     { 0 }
 405 };
 406
 407 static EbmlSyntax matroska_index_pos[] = {
 408     { MATROSKA_ID_CUETRACK,           EBML_UINT, 0, offsetof(MatroskaIndexPos,track) },
 409     { MATROSKA_ID_CUECLUSTERPOSITION, EBML_UINT, 0, offsetof(MatroskaIndexPos,pos)   },
 410     { MATROSKA_ID_CUEBLOCKNUMBER,     EBML_NONE },
 411     { 0 }
 412 };
 413
 414 static EbmlSyntax matroska_index_entry[] = {
 415     { MATROSKA_ID_CUETIME,            EBML_UINT, 0, offsetof(MatroskaIndex,time) },
 416     { MATROSKA_ID_CUETRACKPOSITION,   EBML_NEST, sizeof(MatroskaIndexPos), offsetof(MatroskaIndex,pos), {.n=matroska_index_pos} },
 417     { 0 }
 418 };
 419
 420 static EbmlSyntax matroska_index[] = {
 421     { MATROSKA_ID_POINTENTRY,         EBML_NEST, sizeof(MatroskaIndex), offsetof(MatroskaDemuxContext,index), {.n=matroska_index_entry} },
 422     { 0 }
 423 };
 424
 425 static EbmlSyntax matroska_simpletag[] = {
 426     { MATROSKA_ID_TAGNAME,            EBML_UTF8, 0, offsetof(MatroskaTag,name) },
 427     { MATROSKA_ID_TAGSTRING,          EBML_UTF8, 0, offsetof(MatroskaTag,string) },
 428     { MATROSKA_ID_TAGLANG,            EBML_STR,  0, offsetof(MatroskaTag,lang), {.s="und"} },
 429     { MATROSKA_ID_TAGDEFAULT,         EBML_UINT, 0, offsetof(MatroskaTag,def) },
 430     { MATROSKA_ID_TAGDEFAULT_BUG,     EBML_UINT, 0, offsetof(MatroskaTag,def) },
 431     { MATROSKA_ID_SIMPLETAG,          EBML_NEST, sizeof(MatroskaTag), offsetof(MatroskaTag,sub), {.n=matroska_simpletag} },
 432     { 0 }
 433 };
 434
 435 static EbmlSyntax matroska_tagtargets[] = {
 436     { MATROSKA_ID_TAGTARGETS_TYPE,      EBML_STR,  0, offsetof(MatroskaTagTarget,type) },
 437     { MATROSKA_ID_TAGTARGETS_TYPEVALUE, EBML_UINT, 0, offsetof(MatroskaTagTarget,typevalue), {.u=50} },
 438     { MATROSKA_ID_TAGTARGETS_TRACKUID,  EBML_UINT, 0, offsetof(MatroskaTagTarget,trackuid) },
 439     { MATROSKA_ID_TAGTARGETS_CHAPTERUID,EBML_UINT, 0, offsetof(MatroskaTagTarget,chapteruid) },
 440     { MATROSKA_ID_TAGTARGETS_ATTACHUID, EBML_UINT, 0, offsetof(MatroskaTagTarget,attachuid) },
 441     { 0 }
 442 };
 443
 444 static EbmlSyntax matroska_tag[] = {
 445     { MATROSKA_ID_SIMPLETAG,          EBML_NEST, sizeof(MatroskaTag), offsetof(MatroskaTags,tag), {.n=matroska_simpletag} },
 446     { MATROSKA_ID_TAGTARGETS,         EBML_NEST, 0, offsetof(MatroskaTags,target), {.n=matroska_tagtargets} },
 447     { 0 }
 448 };
 449
 450 static EbmlSyntax matroska_tags[] = {
 451     { MATROSKA_ID_TAG,                EBML_NEST, sizeof(MatroskaTags), offsetof(MatroskaDemuxContext,tags), {.n=matroska_tag} },
 452     { 0 }
 453 };
 454
 455 static EbmlSyntax matroska_seekhead_entry[] = {
 456     { MATROSKA_ID_SEEKID,             EBML_UINT, 0, offsetof(MatroskaSeekhead,id) },
 457     { MATROSKA_ID_SEEKPOSITION,       EBML_UINT, 0, offsetof(MatroskaSeekhead,pos), {.u=-1} },
 458     { 0 }
 459 };
 460
 461 static EbmlSyntax matroska_seekhead[] = {
 462     { MATROSKA_ID_SEEKENTRY,          EBML_NEST, sizeof(MatroskaSeekhead), offsetof(MatroskaDemuxContext,seekhead), {.n=matroska_seekhead_entry} },
 463     { 0 }
 464 };
 465
 466 static EbmlSyntax matroska_segment[] = {
 467     { MATROSKA_ID_INFO,           EBML_NEST, 0, 0, {.n=matroska_info       } },
 468     { MATROSKA_ID_TRACKS,         EBML_NEST, 0, 0, {.n=matroska_tracks     } },
 469     { MATROSKA_ID_ATTACHMENTS,    EBML_NEST, 0, 0, {.n=matroska_attachments} },
 470     { MATROSKA_ID_CHAPTERS,       EBML_NEST, 0, 0, {.n=matroska_chapters   } },
 471     { MATROSKA_ID_CUES,           EBML_NEST, 0, 0, {.n=matroska_index      } },
 472     { MATROSKA_ID_TAGS,           EBML_NEST, 0, 0, {.n=matroska_tags       } },
 473     { MATROSKA_ID_SEEKHEAD,       EBML_NEST, 0, 0, {.n=matroska_seekhead   } },
 474     { MATROSKA_ID_CLUSTER,        EBML_STOP },
 475     { 0 }
 476 };
 477
 478 static EbmlSyntax matroska_segments[] = {
 479     { MATROSKA_ID_SEGMENT,        EBML_NEST, 0, 0, {.n=matroska_segment    } },
 480     { 0 }
 481 };
 482
 483 static EbmlSyntax matroska_blockgroup[] = {
 484     { MATROSKA_ID_BLOCK,          EBML_BIN,  0, offsetof(MatroskaBlock,bin) },
 485     { MATROSKA_ID_SIMPLEBLOCK,    EBML_BIN,  0, offsetof(MatroskaBlock,bin) },
 486     { MATROSKA_ID_BLOCKDURATION,  EBML_UINT, 0, offsetof(MatroskaBlock,duration), {.u=AV_NOPTS_VALUE} },
 487     { MATROSKA_ID_BLOCKREFERENCE, EBML_UINT, 0, offsetof(MatroskaBlock,reference) },
 488     { 1,                          EBML_UINT, 0, offsetof(MatroskaBlock,non_simple), {.u=1} },
 489     { 0 }
 490 };
 491
 492 static EbmlSyntax matroska_cluster[] = {
 493     { MATROSKA_ID_CLUSTERTIMECODE,EBML_UINT,0, offsetof(MatroskaCluster,timecode) },
 494     { MATROSKA_ID_BLOCKGROUP,     EBML_NEST, sizeof(MatroskaBlock), offsetof(MatroskaCluster,blocks), {.n=matroska_blockgroup} },
 495     { MATROSKA_ID_SIMPLEBLOCK,    EBML_PASS, sizeof(MatroskaBlock), offsetof(MatroskaCluster,blocks), {.n=matroska_blockgroup} },
 496     { MATROSKA_ID_CLUSTERPOSITION,EBML_NONE },
 497     { MATROSKA_ID_CLUSTERPREVSIZE,EBML_NONE },
 498     { 0 }
 499 };
 500
 501 static EbmlSyntax matroska_clusters[] = {
 502     { MATROSKA_ID_CLUSTER,        EBML_NEST, 0, 0, {.n=matroska_cluster} },
 503     { MATROSKA_ID_INFO,           EBML_NONE },
 504     { MATROSKA_ID_CUES,           EBML_NONE },
 505     { MATROSKA_ID_TAGS,           EBML_NONE },
 506     { MATROSKA_ID_SEEKHEAD,       EBML_NONE },
 507     { 0 }
 508 };
 509
 510 static const char *matroska_doctypes[] = { "matroska", "webm" };
 511
 512 /*
 513  * Return: Whether we reached the end of a level in the hierarchy or not.
 514  */
 515 static int ebml_level_end(MatroskaDemuxContext *matroska)
 516 {
 517     ByteIOContext *pb = matroska->ctx->pb;
 518     int64_t pos = url_ftell(pb);
 519
 520     if (matroska->num_levels > 0) {
 521         MatroskaLevel *level = &matroska->levels[matroska->num_levels - 1];
 522         if (pos - level->start >= level->length || matroska->current_id) {
 523             matroska->num_levels--;
 524             return 1;
 525         }
 526     }
 527     return 0;
 528 }
 529
 530 /*
 531  * Read: an "EBML number", which is defined as a variable-length
 532  * array of bytes. The first byte indicates the length by giving a
 533  * number of 0-bits followed by a one. The position of the first
 534  * "one" bit inside the first byte indicates the length of this
 535  * number.
 536  * Returns: number of bytes read, < 0 on error
 537  */
 538 static int ebml_read_num(MatroskaDemuxContext *matroska, ByteIOContext *pb,
 539                          int max_size, uint64_t *number)
 540 {
 541     int len_mask = 0x80, read = 1, n = 1;
 542     int64_t total = 0;
 543
 544     /* The first byte tells us the length in bytes - get_byte() can normally
 545      * return 0, but since that's not a valid first ebmlID byte, we can
 546      * use it safely here to catch EOS. */
 547     if (!(total = get_byte(pb))) {
 548         /* we might encounter EOS here */
 549         if (!url_feof(pb)) {
 550             int64_t pos = url_ftell(pb);
 551             av_log(matroska->ctx, AV_LOG_ERROR,
 552                    "Read error at pos. %"PRIu64" (0x%"PRIx64")\n",
 553                    pos, pos);
 554         }
 555         return AVERROR(EIO); /* EOS or actual I/O error */
 556     }
 557
 558     /* get the length of the EBML number */
 559     while (read <= max_size && !(total & len_mask)) {
 560         read++;
 561         len_mask >>= 1;
 562     }
 563     if (read > max_size) {
 564         int64_t pos = url_ftell(pb) - 1;
 565         av_log(matroska->ctx, AV_LOG_ERROR,
 566                "Invalid EBML number size tag 0x%02x at pos %"PRIu64" (0x%"PRIx64")\n",
 567                (uint8_t) total, pos, pos);
 568         return AVERROR_INVALIDDATA;
 569     }
 570
 571     /* read out length */
 572     total &= ~len_mask;
 573     while (n++ < read)
 574         total = (total << 8) | get_byte(pb);
 575
 576     *number = total;
 577
 578     return read;
 579 }
 580
 581 /*
 582  * Read the next element as an unsigned int.
 583  * 0 is success, < 0 is failure.
 584  */
 585 static int ebml_read_uint(ByteIOContext *pb, int size, uint64_t *num)
 586 {
 587     int n = 0;
 588
 589     if (size < 1 || size > 8)
 590         return AVERROR_INVALIDDATA;
 591
 592     /* big-endian ordering; build up number */
 593     *num = 0;
 594     while (n++ < size)
 595         *num = (*num << 8) | get_byte(pb);
 596
 597     return 0;
 598 }
 599
 600 /*
 601  * Read the next element as a float.
 602  * 0 is success, < 0 is failure.
 603  */
 604 static int ebml_read_float(ByteIOContext *pb, int size, double *num)
 605 {
 606     if (size == 4) {
 607         *num= av_int2flt(get_be32(pb));
 608     } else if(size==8){
 609         *num= av_int2dbl(get_be64(pb));
 610     } else
 611         return AVERROR_INVALIDDATA;
 612
 613     return 0;
 614 }
 615
 616 /*
 617  * Read the next element as an ASCII string.
 618  * 0 is success, < 0 is failure.
 619  */
 620 static int ebml_read_ascii(ByteIOContext *pb, int size, char **str)
 621 {
 622     av_free(*str);
 623     /* EBML strings are usually not 0-terminated, so we allocate one
 624      * byte more, read the string and NULL-terminate it ourselves. */
 625     if (!(*str = av_malloc(size + 1)))
 626         return AVERROR(ENOMEM);
 627     if (get_buffer(pb, (uint8_t *) *str, size) != size) {
 628         av_freep(str);
 629         return AVERROR(EIO);
 630     }
 631     (*str)[size] = '\0';
 632
 633     return 0;
 634 }
 635
 636 /*
 637  * Read the next element as binary data.
 638  * 0 is success, < 0 is failure.
 639  */
 640 static int ebml_read_binary(ByteIOContext *pb, int length, EbmlBin *bin)
 641 {
 642     av_free(bin->data);
 643     if (!(bin->data = av_malloc(length)))
 644         return AVERROR(ENOMEM);
 645
 646     bin->size = length;
 647     bin->pos  = url_ftell(pb);
 648     if (get_buffer(pb, bin->data, length) != length) {
 649         av_freep(&bin->data);
 650         return AVERROR(EIO);
 651     }
 652
 653     return 0;
 654 }
 655
 656 /*
 657  * Read the next element, but only the header. The contents
 658  * are supposed to be sub-elements which can be read separately.
 659  * 0 is success, < 0 is failure.
 660  */
 661 static int ebml_read_master(MatroskaDemuxContext *matroska, uint64_t length)
 662 {
 663     ByteIOContext *pb = matroska->ctx->pb;
 664     MatroskaLevel *level;
 665
 666     if (matroska->num_levels >= EBML_MAX_DEPTH) {
 667         av_log(matroska->ctx, AV_LOG_ERROR,
 668                "File moves beyond max. allowed depth (%d)\n", EBML_MAX_DEPTH);
 669         return AVERROR(ENOSYS);
 670     }
 671
 672     level = &matroska->levels[matroska->num_levels++];
 673     level->start = url_ftell(pb);
 674     level->length = length;
 675
 676     return 0;
 677 }
 678
 679 /*
 680  * Read signed/unsigned "EBML" numbers.
 681  * Return: number of bytes processed, < 0 on error
 682  */
 683 static int matroska_ebmlnum_uint(MatroskaDemuxContext *matroska,
 684                                  uint8_t *data, uint32_t size, uint64_t *num)
 685 {
 686     ByteIOContext pb;
 687     init_put_byte(&pb, data, size, 0, NULL, NULL, NULL, NULL);
 688     return ebml_read_num(matroska, &pb, FFMIN(size, 8), num);
 689 }
 690
 691 /*
 692  * Same as above, but signed.
 693  */
 694 static int matroska_ebmlnum_sint(MatroskaDemuxContext *matroska,
 695                                  uint8_t *data, uint32_t size, int64_t *num)
 696 {
 697     uint64_t unum;
 698     int res;
 699
 700     /* read as unsigned number first */
 701     if ((res = matroska_ebmlnum_uint(matroska, data, size, &unum)) < 0)
 702         return res;
 703
 704     /* make signed (weird way) */
 705     *num = unum - ((1LL << (7*res - 1)) - 1);
 706
 707     return res;
 708 }
 709
 710 static int ebml_parse_elem(MatroskaDemuxContext *matroska,
 711                            EbmlSyntax *syntax, void *data);
 712
 713 static int ebml_parse_id(MatroskaDemuxContext *matroska, EbmlSyntax *syntax,
 714                          uint32_t id, void *data)
 715 {
 716     int i;
 717     for (i=0; syntax[i].id; i++)
 718         if (id == syntax[i].id)
 719             break;
 720     if (!syntax[i].id && id == MATROSKA_ID_CLUSTER &&
 721         matroska->num_levels > 0 &&
 722         matroska->levels[matroska->num_levels-1].length == 0xffffffffffffff)
 723         return 0;  // we reached the end of an unknown size cluster
 724     if (!syntax[i].id && id != EBML_ID_VOID && id != EBML_ID_CRC32)
 725         av_log(matroska->ctx, AV_LOG_INFO, "Unknown entry 0x%X\n", id);
 726     return ebml_parse_elem(matroska, &syntax[i], data);
 727 }
 728
 729 static int ebml_parse(MatroskaDemuxContext *matroska, EbmlSyntax *syntax,
 730                       void *data)
 731 {
 732     if (!matroska->current_id) {
 733         uint64_t id;
 734         int res = ebml_read_num(matroska, matroska->ctx->pb, 4, &id);
 735         if (res < 0)
 736             return res;
 737         matroska->current_id = id | 1 << 7*res;
 738     }
 739     return ebml_parse_id(matroska, syntax, matroska->current_id, data);
 740 }
 741
 742 static int ebml_parse_nest(MatroskaDemuxContext *matroska, EbmlSyntax *syntax,
 743                            void *data)
 744 {
 745     int i, res = 0;
 746
 747     for (i=0; syntax[i].id; i++)
 748         switch (syntax[i].type) {
 749         case EBML_UINT:
 750             *(uint64_t *)((char *)data+syntax[i].data_offset) = syntax[i].def.u;
 751             break;
 752         case EBML_FLOAT:
 753             *(double   *)((char *)data+syntax[i].data_offset) = syntax[i].def.f;
 754             break;
 755         case EBML_STR:
 756         case EBML_UTF8:
 757             *(char    **)((char *)data+syntax[i].data_offset) = av_strdup(syntax[i].def.s);
 758             break;
 759         }
 760
 761     while (!res && !ebml_level_end(matroska))
 762         res = ebml_parse(matroska, syntax, data);
 763
 764     return res;
 765 }
 766
 767 static int ebml_parse_elem(MatroskaDemuxContext *matroska,
 768                            EbmlSyntax *syntax, void *data)
 769 {
 770     ByteIOContext *pb = matroska->ctx->pb;
 771     uint32_t id = syntax->id;
 772     uint64_t length;
 773     int res;
 774
 775     data = (char *)data + syntax->data_offset;
 776     if (syntax->list_elem_size) {
 777         EbmlList *list = data;
 778         list->elem = av_realloc(list->elem, (list->nb_elem+1)*syntax->list_elem_size);
 779         data = (char*)list->elem + list->nb_elem*syntax->list_elem_size;
 780         memset(data, 0, syntax->list_elem_size);
 781         list->nb_elem++;
 782     }
 783
 784     if (syntax->type != EBML_PASS && syntax->type != EBML_STOP) {
 785         matroska->current_id = 0;
 786         if ((res = ebml_read_num(matroska, pb, 8, &length)) < 0)
 787             return res;
 788     }
 789
 790     switch (syntax->type) {
 791     case EBML_UINT:  res = ebml_read_uint  (pb, length, data);  break;
 792     case EBML_FLOAT: res = ebml_read_float (pb, length, data);  break;
 793     case EBML_STR:
 794     case EBML_UTF8:  res = ebml_read_ascii (pb, length, data);  break;
 795     case EBML_BIN:   res = ebml_read_binary(pb, length, data);  break;
 796     case EBML_NEST:  if ((res=ebml_read_master(matroska, length)) < 0)
 797                          return res;
 798                      if (id == MATROSKA_ID_SEGMENT)
 799                          matroska->segment_start = url_ftell(matroska->ctx->pb);
 800                      return ebml_parse_nest(matroska, syntax->def.n, data);
 801     case EBML_PASS:  return ebml_parse_id(matroska, syntax->def.n, id, data);
 802     case EBML_STOP:  return 1;
 803     default:         return url_fseek(pb,length,SEEK_CUR)<0 ? AVERROR(EIO) : 0;
 804     }
 805     if (res == AVERROR_INVALIDDATA)
 806         av_log(matroska->ctx, AV_LOG_ERROR, "Invalid element\n");
 807     else if (res == AVERROR(EIO))
 808         av_log(matroska->ctx, AV_LOG_ERROR, "Read error\n");
 809     return res;
 810 }
 811
 812 static void ebml_free(EbmlSyntax *syntax, void *data)
 813 {
 814     int i, j;
 815     for (i=0; syntax[i].id; i++) {
 816         void *data_off = (char *)data + syntax[i].data_offset;
 817         switch (syntax[i].type) {
 818         case EBML_STR:
 819         case EBML_UTF8:  av_freep(data_off);                      break;
 820         case EBML_BIN:   av_freep(&((EbmlBin *)data_off)->data);  break;
 821         case EBML_NEST:
 822             if (syntax[i].list_elem_size) {
 823                 EbmlList *list = data_off;
 824                 char *ptr = list->elem;
 825                 for (j=0; j<list->nb_elem; j++, ptr+=syntax[i].list_elem_size)
 826                     ebml_free(syntax[i].def.n, ptr);
 827                 av_free(list->elem);
 828             } else
 829                 ebml_free(syntax[i].def.n, data_off);
 830         default:  break;
 831         }
 832     }
 833 }
 834
 835
 836 /*
 837  * Autodetecting...
 838  */
 839 static int matroska_probe(AVProbeData *p)
 840 {
 841     uint64_t total = 0;
 842     int len_mask = 0x80, size = 1, n = 1, i;
 843
 844     /* EBML header? */
 845     if (AV_RB32(p->buf) != EBML_ID_HEADER)
 846         return 0;
 847
 848     /* length of header */
 849     total = p->buf[4];
 850     while (size <= 8 && !(total & len_mask)) {
 851         size++;
 852         len_mask >>= 1;
 853     }
 854     if (size > 8)
 855       return 0;
 856     total &= (len_mask - 1);
 857     while (n < size)
 858         total = (total << 8) | p->buf[4 + n++];
 859
 860     /* Does the probe data contain the whole header? */
 861     if (p->buf_size < 4 + size + total)
 862       return 0;
 863
 864     /* The header should contain a known document type. For now,
 865      * we don't parse the whole header but simply check for the
 866      * availability of that array of characters inside the header.
 867      * Not fully fool-proof, but good enough. */
 868     for (i = 0; i < FF_ARRAY_ELEMS(matroska_doctypes); i++) {
 869         int probelen = strlen(matroska_doctypes[i]);
 870         for (n = 4+size; n <= 4+size+total-probelen; n++)
 871             if (!memcmp(p->buf+n, matroska_doctypes[i], probelen))
 872                 return AVPROBE_SCORE_MAX;
 873     }
 874
 875     // probably valid EBML header but no recognized doctype
 876     return AVPROBE_SCORE_MAX/2;
 877 }
 878
 879 static MatroskaTrack *matroska_find_track_by_num(MatroskaDemuxContext *matroska,
 880                                                  int num)
 881 {
 882     MatroskaTrack *tracks = matroska->tracks.elem;
 883     int i;
 884
 885     for (i=0; i < matroska->tracks.nb_elem; i++)
 886         if (tracks[i].num == num)
 887             return &tracks[i];
 888
 889     av_log(matroska->ctx, AV_LOG_ERROR, "Invalid track number %d\n", num);
 890     return NULL;
 891 }
 892
 893 static int matroska_decode_buffer(uint8_t** buf, int* buf_size,
 894                                   MatroskaTrack *track)
 895 {
 896     MatroskaTrackEncoding *encodings = track->encodings.elem;
 897     uint8_t* data = *buf;
 898     int isize = *buf_size;
 899     uint8_t* pkt_data = NULL;
 900     int pkt_size = isize;
 901     int result = 0;
 902     int olen;
 903
 904     if (pkt_size >= 10000000)
 905         return -1;
 906
 907     switch (encodings[0].compression.algo) {
 908     case MATROSKA_TRACK_ENCODING_COMP_HEADERSTRIP:
 909         return encodings[0].compression.settings.size;
 910     case MATROSKA_TRACK_ENCODING_COMP_LZO:
 911         do {
 912             olen = pkt_size *= 3;
 913             pkt_data = av_realloc(pkt_data, pkt_size+AV_LZO_OUTPUT_PADDING);
 914             result = av_lzo1x_decode(pkt_data, &olen, data, &isize);
 915         } while (result==AV_LZO_OUTPUT_FULL && pkt_size<10000000);
 916         if (result)
 917             goto failed;
 918         pkt_size -= olen;
 919         break;
 920 #if CONFIG_ZLIB
 921     case MATROSKA_TRACK_ENCODING_COMP_ZLIB: {
 922         z_stream zstream = {0};
 923         if (inflateInit(&zstream) != Z_OK)
 924             return -1;
 925         zstream.next_in = data;
 926         zstream.avail_in = isize;
 927         do {
 928             pkt_size *= 3;
 929             pkt_data = av_realloc(pkt_data, pkt_size);
 930             zstream.avail_out = pkt_size - zstream.total_out;
 931             zstream.next_out = pkt_data + zstream.total_out;
 932             result = inflate(&zstream, Z_NO_FLUSH);
 933         } while (result==Z_OK && pkt_size<10000000);
 934         pkt_size = zstream.total_out;
 935         inflateEnd(&zstream);
 936         if (result != Z_STREAM_END)
 937             goto failed;
 938         break;
 939     }
 940 #endif
 941 #if CONFIG_BZLIB
 942     case MATROSKA_TRACK_ENCODING_COMP_BZLIB: {
 943         bz_stream bzstream = {0};
 944         if (BZ2_bzDecompressInit(&bzstream, 0, 0) != BZ_OK)
 945             return -1;
 946         bzstream.next_in = data;
 947         bzstream.avail_in = isize;
 948         do {
 949             pkt_size *= 3;
 950             pkt_data = av_realloc(pkt_data, pkt_size);
 951             bzstream.avail_out = pkt_size - bzstream.total_out_lo32;
 952             bzstream.next_out = pkt_data + bzstream.total_out_lo32;
 953             result = BZ2_bzDecompress(&bzstream);
 954         } while (result==BZ_OK && pkt_size<10000000);
 955         pkt_size = bzstream.total_out_lo32;
 956         BZ2_bzDecompressEnd(&bzstream);
 957         if (result != BZ_STREAM_END)
 958             goto failed;
 959         break;
 960     }
 961 #endif
 962     default:
 963         return -1;
 964     }
 965
 966     *buf = pkt_data;
 967     *buf_size = pkt_size;
 968     return 0;
 969  failed:
 970     av_free(pkt_data);
 971     return -1;
 972 }
 973
 974 static void matroska_fix_ass_packet(MatroskaDemuxContext *matroska,
 975                                     AVPacket *pkt, uint64_t display_duration)
 976 {
 977     char *line, *layer, *ptr = pkt->data, *end = ptr+pkt->size;
 978     for (; *ptr!=',' && ptr<end-1; ptr++);
 979     if (*ptr == ',')
 980         layer = ++ptr;
 981     for (; *ptr!=',' && ptr<end-1; ptr++);
 982     if (*ptr == ',') {
 983         int64_t end_pts = pkt->pts + display_duration;
 984         int sc = matroska->time_scale * pkt->pts / 10000000;
 985         int ec = matroska->time_scale * end_pts  / 10000000;
 986         int sh, sm, ss, eh, em, es, len;
 987         sh = sc/360000;  sc -= 360000*sh;
 988         sm = sc/  6000;  sc -=   6000*sm;
 989         ss = sc/   100;  sc -=    100*ss;
 990         eh = ec/360000;  ec -= 360000*eh;
 991         em = ec/  6000;  ec -=   6000*em;
 992         es = ec/   100;  ec -=    100*es;
 993         *ptr++ = '\0';
 994         len = 50 + end-ptr + FF_INPUT_BUFFER_PADDING_SIZE;
 995         if (!(line = av_malloc(len)))
 996             return;
 997         snprintf(line,len,"Dialogue: %s,%d:%02d:%02d.%02d,%d:%02d:%02d.%02d,%s\r\n",
 998                  layer, sh, sm, ss, sc, eh, em, es, ec, ptr);
 999         av_free(pkt->data);
1000         pkt->data = line;
1001         pkt->size = strlen(line);
1002     }
1003 }
1004
1005 static void matroska_merge_packets(AVPacket *out, AVPacket *in)
1006 {
1007     out->data = av_realloc(out->data, out->size+in->size);
1008     memcpy(out->data+out->size, in->data, in->size);
1009     out->size += in->size;
1010     av_destruct_packet(in);
1011     av_free(in);
1012 }
1013
1014 static void matroska_convert_tag(AVFormatContext *s, EbmlList *list,
1015                                  AVMetadata **metadata, char *prefix)
1016 {
1017     MatroskaTag *tags = list->elem;
1018     char key[1024];
1019     int i;
1020
1021     for (i=0; i < list->nb_elem; i++) {
1022         const char *lang = strcmp(tags[i].lang, "und") ? tags[i].lang : NULL;
1023         if (prefix)  snprintf(key, sizeof(key), "%s/%s", prefix, tags[i].name);
1024         else         av_strlcpy(key, tags[i].name, sizeof(key));
1025         if (tags[i].def || !lang) {
1026         av_metadata_set2(metadata, key, tags[i].string, 0);
1027         if (tags[i].sub.nb_elem)
1028             matroska_convert_tag(s, &tags[i].sub, metadata, key);
1029         }
1030         if (lang) {
1031             av_strlcat(key, "-", sizeof(key));
1032             av_strlcat(key, lang, sizeof(key));
1033             av_metadata_set2(metadata, key, tags[i].string, 0);
1034             if (tags[i].sub.nb_elem)
1035                 matroska_convert_tag(s, &tags[i].sub, metadata, key);
1036         }
1037     }
1038 }
1039
1040 static void matroska_convert_tags(AVFormatContext *s)
1041 {
1042     MatroskaDemuxContext *matroska = s->priv_data;
1043     MatroskaTags *tags = matroska->tags.elem;
1044     int i, j;
1045
1046     for (i=0; i < matroska->tags.nb_elem; i++) {
1047         if (tags[i].target.attachuid) {
1048             MatroskaAttachement *attachment = matroska->attachments.elem;
1049             for (j=0; j<matroska->attachments.nb_elem; j++)
1050                 if (attachment[j].uid == tags[i].target.attachuid)
1051                     matroska_convert_tag(s, &tags[i].tag,
1052                                          &attachment[j].stream->metadata, NULL);
1053         } else if (tags[i].target.chapteruid) {
1054             MatroskaChapter *chapter = matroska->chapters.elem;
1055             for (j=0; j<matroska->chapters.nb_elem; j++)
1056                 if (chapter[j].uid == tags[i].target.chapteruid)
1057                     matroska_convert_tag(s, &tags[i].tag,
1058                                          &chapter[j].chapter->metadata, NULL);
1059         } else if (tags[i].target.trackuid) {
1060             MatroskaTrack *track = matroska->tracks.elem;
1061             for (j=0; j<matroska->tracks.nb_elem; j++)
1062                 if (track[j].uid == tags[i].target.trackuid)
1063                     matroska_convert_tag(s, &tags[i].tag,
1064                                          &track[j].stream->metadata, NULL);
1065         } else {
1066             matroska_convert_tag(s, &tags[i].tag, &s->metadata,
1067                                  tags[i].target.type);
1068         }
1069     }
1070 }
1071
1072 static void matroska_execute_seekhead(MatroskaDemuxContext *matroska)
1073 {
1074     EbmlList *seekhead_list = &matroska->seekhead;
1075     MatroskaSeekhead *seekhead = seekhead_list->elem;
1076     uint32_t level_up = matroska->level_up;
1077     int64_t before_pos = url_ftell(matroska->ctx->pb);
1078     uint32_t saved_id = matroska->current_id;
1079     MatroskaLevel level;
1080     int i;
1081
1082     // we should not do any seeking in the streaming case
1083     if (url_is_streamed(matroska->ctx->pb) ||
1084         (matroska->ctx->flags & AVFMT_FLAG_IGNIDX))
1085         return;
1086
1087     for (i=0; i<seekhead_list->nb_elem; i++) {
1088         int64_t offset = seekhead[i].pos + matroska->segment_start;
1089
1090         if (seekhead[i].pos <= before_pos
1091             || seekhead[i].id == MATROSKA_ID_SEEKHEAD
1092             || seekhead[i].id == MATROSKA_ID_CLUSTER)
1093             continue;
1094
1095         /* seek */
1096         if (url_fseek(matroska->ctx->pb, offset, SEEK_SET) != offset)
1097             continue;
1098
1099         /* We don't want to lose our seekhead level, so we add
1100          * a dummy. This is a crude hack. */
1101         if (matroska->num_levels == EBML_MAX_DEPTH) {
1102             av_log(matroska->ctx, AV_LOG_INFO,
1103                    "Max EBML element depth (%d) reached, "
1104                    "cannot parse further.\n", EBML_MAX_DEPTH);
1105             break;
1106         }
1107
1108         level.start = 0;
1109         level.length = (uint64_t)-1;
1110         matroska->levels[matroska->num_levels] = level;
1111         matroska->num_levels++;
1112         matroska->current_id = 0;
1113
1114         ebml_parse(matroska, matroska_segment, matroska);
1115
1116         /* remove dummy level */
1117         while (matroska->num_levels) {
1118             uint64_t length = matroska->levels[--matroska->num_levels].length;
1119             if (length == (uint64_t)-1)
1120                 break;
1121         }
1122     }
1123
1124     /* seek back */
1125     url_fseek(matroska->ctx->pb, before_pos, SEEK_SET);
1126     matroska->level_up = level_up;
1127     matroska->current_id = saved_id;
1128 }
1129
1130 static int matroska_aac_profile(char *codec_id)
1131 {
1132     static const char * const aac_profiles[] = { "MAIN", "LC", "SSR" };
1133     int profile;
1134
1135     for (profile=0; profile<FF_ARRAY_ELEMS(aac_profiles); profile++)
1136         if (strstr(codec_id, aac_profiles[profile]))
1137             break;
1138     return profile + 1;
1139 }
1140
1141 static int matroska_aac_sri(int samplerate)
1142 {
1143     int sri;
1144
1145     for (sri=0; sri<FF_ARRAY_ELEMS(ff_mpeg4audio_sample_rates); sri++)
1146         if (ff_mpeg4audio_sample_rates[sri] == samplerate)
1147             break;
1148     return sri;
1149 }
1150
1151 static int matroska_read_header(AVFormatContext *s, AVFormatParameters *ap)
1152 {
1153     MatroskaDemuxContext *matroska = s->priv_data;
1154     EbmlList *attachements_list = &matroska->attachments;
1155     MatroskaAttachement *attachements;
1156     EbmlList *chapters_list = &matroska->chapters;
1157     MatroskaChapter *chapters;
1158     MatroskaTrack *tracks;
1159     EbmlList *index_list;
1160     MatroskaIndex *index;
1161     int index_scale = 1;
1162     uint64_t max_start = 0;
1163     Ebml ebml = { 0 };
1164     AVStream *st;
1165     int i, j, res;
1166
1167     matroska->ctx = s;
1168
1169     /* First read the EBML header. */
1170     if (ebml_parse(matroska, ebml_syntax, &ebml)
1171         || ebml.version > EBML_VERSION       || ebml.max_size > sizeof(uint64_t)
1172         || ebml.id_length > sizeof(uint32_t) || ebml.doctype_version > 2) {
1173         av_log(matroska->ctx, AV_LOG_ERROR,
1174                "EBML header using unsupported features\n"
1175                "(EBML version %"PRIu64", doctype %s, doc version %"PRIu64")\n",
1176                ebml.version, ebml.doctype, ebml.doctype_version);
1177         ebml_free(ebml_syntax, &ebml);
1178         return AVERROR_PATCHWELCOME;
1179     }
1180     for (i = 0; i < FF_ARRAY_ELEMS(matroska_doctypes); i++)
1181         if (!strcmp(ebml.doctype, matroska_doctypes[i]))
1182             break;
1183     if (i >= FF_ARRAY_ELEMS(matroska_doctypes)) {
1184         av_log(s, AV_LOG_WARNING, "Unknown EBML doctype '%s'\n", ebml.doctype);
1185     }
1186     ebml_free(ebml_syntax, &ebml);
1187
1188     /* The next thing is a segment. */
1189     if ((res = ebml_parse(matroska, matroska_segments, matroska)) < 0)
1190         return res;
1191     matroska_execute_seekhead(matroska);
1192
1193     if (!matroska->time_scale)
1194         matroska->time_scale = 1000000;
1195     if (matroska->duration)
1196         matroska->ctx->duration = matroska->duration * matroska->time_scale
1197                                   * 1000 / AV_TIME_BASE;
1198     av_metadata_set2(&s->metadata, "title", matroska->title, 0);
1199
1200     tracks = matroska->tracks.elem;
1201     for (i=0; i < matroska->tracks.nb_elem; i++) {
1202         MatroskaTrack *track = &tracks[i];
1203         enum CodecID codec_id = CODEC_ID_NONE;
1204         EbmlList *encodings_list = &tracks->encodings;
1205         MatroskaTrackEncoding *encodings = encodings_list->elem;
1206         uint8_t *extradata = NULL;
1207         int extradata_size = 0;
1208         int extradata_offset = 0;
1209         ByteIOContext b;
1210
1211         /* Apply some sanity checks. */
1212         if (track->type != MATROSKA_TRACK_TYPE_VIDEO &&
1213             track->type != MATROSKA_TRACK_TYPE_AUDIO &&
1214             track->type != MATROSKA_TRACK_TYPE_SUBTITLE) {
1215             av_log(matroska->ctx, AV_LOG_INFO,
1216                    "Unknown or unsupported track type %"PRIu64"\n",
1217                    track->type);
1218             continue;
1219         }
1220         if (track->codec_id == NULL)
1221             continue;
1222
1223         if (track->type == MATROSKA_TRACK_TYPE_VIDEO) {
1224             if (!track->default_duration)
1225                 track->default_duration = 1000000000/track->video.frame_rate;
1226             if (!track->video.display_width)
1227                 track->video.display_width = track->video.pixel_width;
1228             if (!track->video.display_height)
1229                 track->video.display_height = track->video.pixel_height;
1230         } else if (track->type == MATROSKA_TRACK_TYPE_AUDIO) {
1231             if (!track->audio.out_samplerate)
1232                 track->audio.out_samplerate = track->audio.samplerate;
1233         }
1234         if (encodings_list->nb_elem > 1) {
1235             av_log(matroska->ctx, AV_LOG_ERROR,
1236                    "Multiple combined encodings no supported");
1237         } else if (encodings_list->nb_elem == 1) {
1238             if (encodings[0].type ||
1239                 (encodings[0].compression.algo != MATROSKA_TRACK_ENCODING_COMP_HEADERSTRIP &&
1240 #if CONFIG_ZLIB
1241                  encodings[0].compression.algo != MATROSKA_TRACK_ENCODING_COMP_ZLIB &&
1242 #endif
1243 #if CONFIG_BZLIB
1244                  encodings[0].compression.algo != MATROSKA_TRACK_ENCODING_COMP_BZLIB &&
1245 #endif
1246                  encodings[0].compression.algo != MATROSKA_TRACK_ENCODING_COMP_LZO)) {
1247                 encodings[0].scope = 0;
1248                 av_log(matroska->ctx, AV_LOG_ERROR,
1249                        "Unsupported encoding type");
1250             } else if (track->codec_priv.size && encodings[0].scope&2) {
1251                 uint8_t *codec_priv = track->codec_priv.data;
1252                 int offset = matroska_decode_buffer(&track->codec_priv.data,
1253                                                     &track->codec_priv.size,
1254                                                     track);
1255                 if (offset < 0) {
1256                     track->codec_priv.data = NULL;
1257                     track->codec_priv.size = 0;
1258                     av_log(matroska->ctx, AV_LOG_ERROR,
1259                            "Failed to decode codec private data\n");
1260                 } else if (offset > 0) {
1261                     track->codec_priv.data = av_malloc(track->codec_priv.size + offset);
1262                     memcpy(track->codec_priv.data,
1263                            encodings[0].compression.settings.data, offset);
1264                     memcpy(track->codec_priv.data+offset, codec_priv,
1265                            track->codec_priv.size);
1266                     track->codec_priv.size += offset;
1267                 }
1268                 if (codec_priv != track->codec_priv.data)
1269                     av_free(codec_priv);
1270             }
1271         }
1272
1273         for(j=0; ff_mkv_codec_tags[j].id != CODEC_ID_NONE; j++){
1274             if(!strncmp(ff_mkv_codec_tags[j].str, track->codec_id,
1275                         strlen(ff_mkv_codec_tags[j].str))){
1276                 codec_id= ff_mkv_codec_tags[j].id;
1277                 break;
1278             }
1279         }
1280
1281         st = track->stream = av_new_stream(s, 0);
1282         if (st == NULL)
1283             return AVERROR(ENOMEM);
1284
1285         if (!strcmp(track->codec_id, "V_MS/VFW/FOURCC")
1286             && track->codec_priv.size >= 40
1287             && track->codec_priv.data != NULL) {
1288             track->ms_compat = 1;
1289             track->video.fourcc = AV_RL32(track->codec_priv.data + 16);
1290             codec_id = ff_codec_get_id(ff_codec_bmp_tags, track->video.fourcc);
1291             extradata_offset = 40;
1292         } else if (!strcmp(track->codec_id, "A_MS/ACM")
1293                    && track->codec_priv.size >= 14
1294                    && track->codec_priv.data != NULL) {
1295             init_put_byte(&b, track->codec_priv.data, track->codec_priv.size,
1296                           URL_RDONLY, NULL, NULL, NULL, NULL);
1297             ff_get_wav_header(&b, st->codec, track->codec_priv.size);
1298             codec_id = st->codec->codec_id;
1299             extradata_offset = FFMIN(track->codec_priv.size, 18);
1300         } else if (!strcmp(track->codec_id, "V_QUICKTIME")
1301                    && (track->codec_priv.size >= 86)
1302                    && (track->codec_priv.data != NULL)) {
1303             track->video.fourcc = AV_RL32(track->codec_priv.data);
1304             codec_id=ff_codec_get_id(codec_movvideo_tags, track->video.fourcc);
1305         } else if (codec_id == CODEC_ID_PCM_S16BE) {
1306             switch (track->audio.bitdepth) {
1307             case  8:  codec_id = CODEC_ID_PCM_U8;     break;
1308             case 24:  codec_id = CODEC_ID_PCM_S24BE;  break;
1309             case 32:  codec_id = CODEC_ID_PCM_S32BE;  break;
1310             }
1311         } else if (codec_id == CODEC_ID_PCM_S16LE) {
1312             switch (track->audio.bitdepth) {
1313             case  8:  codec_id = CODEC_ID_PCM_U8;     break;
1314             case 24:  codec_id = CODEC_ID_PCM_S24LE;  break;
1315             case 32:  codec_id = CODEC_ID_PCM_S32LE;  break;
1316             }
1317         } else if (codec_id==CODEC_ID_PCM_F32LE && track->audio.bitdepth==64) {
1318             codec_id = CODEC_ID_PCM_F64LE;
1319         } else if (codec_id == CODEC_ID_AAC && !track->codec_priv.size) {
1320             int profile = matroska_aac_profile(track->codec_id);
1321             int sri = matroska_aac_sri(track->audio.samplerate);
1322             extradata = av_malloc(5);
1323             if (extradata == NULL)
1324                 return AVERROR(ENOMEM);
1325             extradata[0] = (profile << 3) | ((sri&0x0E) >> 1);
1326             extradata[1] = ((sri&0x01) << 7) | (track->audio.channels<<3);
1327             if (strstr(track->codec_id, "SBR")) {
1328                 sri = matroska_aac_sri(track->audio.out_samplerate);
1329                 extradata[2] = 0x56;
1330                 extradata[3] = 0xE5;
1331                 extradata[4] = 0x80 | (sri<<3);
1332                 extradata_size = 5;
1333             } else
1334                 extradata_size = 2;
1335         } else if (codec_id == CODEC_ID_TTA) {
1336             extradata_size = 30;
1337             extradata = av_mallocz(extradata_size);
1338             if (extradata == NULL)
1339                 return AVERROR(ENOMEM);
1340             init_put_byte(&b, extradata, extradata_size, 1,
1341                           NULL, NULL, NULL, NULL);
1342             put_buffer(&b, "TTA1", 4);
1343             put_le16(&b, 1);
1344             put_le16(&b, track->audio.channels);
1345             put_le16(&b, track->audio.bitdepth);
1346             put_le32(&b, track->audio.out_samplerate);
1347             put_le32(&b, matroska->ctx->duration * track->audio.out_samplerate);
1348         } else if (codec_id == CODEC_ID_RV10 || codec_id == CODEC_ID_RV20 ||
1349                    codec_id == CODEC_ID_RV30 || codec_id == CODEC_ID_RV40) {
1350             extradata_offset = 26;
1351         } else if (codec_id == CODEC_ID_RA_144) {
1352             track->audio.out_samplerate = 8000;
1353             track->audio.channels = 1;
1354         } else if (codec_id == CODEC_ID_RA_288 || codec_id == CODEC_ID_COOK ||
1355                    codec_id == CODEC_ID_ATRAC3 || codec_id == CODEC_ID_SIPR) {
1356             int flavor;
1357             init_put_byte(&b, track->codec_priv.data,track->codec_priv.size,
1358                           0, NULL, NULL, NULL, NULL);
1359             url_fskip(&b, 22);
1360             flavor                       = get_be16(&b);
1361             track->audio.coded_framesize = get_be32(&b);
1362             url_fskip(&b, 12);
1363             track->audio.sub_packet_h    = get_be16(&b);
1364             track->audio.frame_size      = get_be16(&b);
1365             track->audio.sub_packet_size = get_be16(&b);
1366             track->audio.buf = av_malloc(track->audio.frame_size * track->audio.sub_packet_h);
1367             if (codec_id == CODEC_ID_RA_288) {
1368                 st->codec->block_align = track->audio.coded_framesize;
1369                 track->codec_priv.size = 0;
1370             } else {
1371                 if (codec_id == CODEC_ID_SIPR && flavor < 4) {
1372                     const int sipr_bit_rate[4] = { 6504, 8496, 5000, 16000 };
1373                     track->audio.sub_packet_size = ff_sipr_subpk_size[flavor];
1374                     st->codec->bit_rate = sipr_bit_rate[flavor];
1375                 }
1376                 st->codec->block_align = track->audio.sub_packet_size;
1377                 extradata_offset = 78;
1378             }
1379         }
1380         track->codec_priv.size -= extradata_offset;
1381
1382         if (codec_id == CODEC_ID_NONE)
1383             av_log(matroska->ctx, AV_LOG_INFO,
1384                    "Unknown/unsupported CodecID %s.\n", track->codec_id);
1385
1386         if (track->time_scale < 0.01)
1387             track->time_scale = 1.0;
1388         av_set_pts_info(st, 64, matroska->time_scale*track->time_scale, 1000*1000*1000); /* 64 bit pts in ns */
1389
1390         st->codec->codec_id = codec_id;
1391         st->start_time = 0;
1392         if (strcmp(track->language, "und"))
1393             av_metadata_set2(&st->metadata, "language", track->language, 0);
1394         av_metadata_set2(&st->metadata, "title", track->name, 0);
1395
1396         if (track->flag_default)
1397             st->disposition |= AV_DISPOSITION_DEFAULT;
1398         if (track->flag_forced)
1399             st->disposition |= AV_DISPOSITION_FORCED;
1400
1401         if (track->default_duration)
1402             av_reduce(&st->codec->time_base.num, &st->codec->time_base.den,
1403                       track->default_duration, 1000000000, 30000);
1404
1405         if (!st->codec->extradata) {
1406             if(extradata){
1407                 st->codec->extradata = extradata;
1408                 st->codec->extradata_size = extradata_size;
1409             } else if(track->codec_priv.data && track->codec_priv.size > 0){
1410                 st->codec->extradata = av_mallocz(track->codec_priv.size +
1411                                                   FF_INPUT_BUFFER_PADDING_SIZE);
1412                 if(st->codec->extradata == NULL)
1413                     return AVERROR(ENOMEM);
1414                 st->codec->extradata_size = track->codec_priv.size;
1415                 memcpy(st->codec->extradata,
1416                        track->codec_priv.data + extradata_offset,
1417                        track->codec_priv.size);
1418             }
1419         }
1420
1421         if (track->type == MATROSKA_TRACK_TYPE_VIDEO) {
1422             st->codec->codec_type = AVMEDIA_TYPE_VIDEO;
1423             st->codec->codec_tag  = track->video.fourcc;
1424             st->codec->width  = track->video.pixel_width;
1425             st->codec->height = track->video.pixel_height;
1426             av_reduce(&st->sample_aspect_ratio.num,
1427                       &st->sample_aspect_ratio.den,
1428                       st->codec->height * track->video.display_width,
1429                       st->codec-> width * track->video.display_height,
1430                       255);
1431             if (st->codec->codec_id != CODEC_ID_H264)
1432             st->need_parsing = AVSTREAM_PARSE_HEADERS;
1433             if (track->default_duration)
1434                 st->avg_frame_rate = av_d2q(1000000000.0/track->default_duration, INT_MAX);
1435         } else if (track->type == MATROSKA_TRACK_TYPE_AUDIO) {
1436             st->codec->codec_type = AVMEDIA_TYPE_AUDIO;
1437             st->codec->sample_rate = track->audio.out_samplerate;
1438             st->codec->channels = track->audio.channels;
1439             if (st->codec->codec_id != CODEC_ID_AAC)
1440             st->need_parsing = AVSTREAM_PARSE_HEADERS;
1441         } else if (track->type == MATROSKA_TRACK_TYPE_SUBTITLE) {
1442             st->codec->codec_type = AVMEDIA_TYPE_SUBTITLE;
1443         }
1444     }
1445
1446     attachements = attachements_list->elem;
1447     for (j=0; j<attachements_list->nb_elem; j++) {
1448         if (!(attachements[j].filename && attachements[j].mime &&
1449               attachements[j].bin.data && attachements[j].bin.size > 0)) {
1450             av_log(matroska->ctx, AV_LOG_ERROR, "incomplete attachment\n");
1451         } else {
1452             AVStream *st = av_new_stream(s, 0);
1453             if (st == NULL)
1454                 break;
1455             av_metadata_set2(&st->metadata, "filename",attachements[j].filename, 0);
1456             st->codec->codec_id = CODEC_ID_NONE;
1457             st->codec->codec_type = AVMEDIA_TYPE_ATTACHMENT;
1458             st->codec->extradata  = av_malloc(attachements[j].bin.size);
1459             if(st->codec->extradata == NULL)
1460                 break;
1461             st->codec->extradata_size = attachements[j].bin.size;
1462             memcpy(st->codec->extradata, attachements[j].bin.data, attachements[j].bin.size);
1463
1464             for (i=0; ff_mkv_mime_tags[i].id != CODEC_ID_NONE; i++) {
1465                 if (!strncmp(ff_mkv_mime_tags[i].str, attachements[j].mime,
1466                              strlen(ff_mkv_mime_tags[i].str))) {
1467                     st->codec->codec_id = ff_mkv_mime_tags[i].id;
1468                     break;
1469                 }
1470             }
1471             attachements[j].stream = st;
1472         }
1473     }
1474
1475     chapters = chapters_list->elem;
1476     for (i=0; i<chapters_list->nb_elem; i++)
1477         if (chapters[i].start != AV_NOPTS_VALUE && chapters[i].uid
1478             && (max_start==0 || chapters[i].start > max_start)) {
1479             chapters[i].chapter =
1480             ff_new_chapter(s, chapters[i].uid, (AVRational){1, 1000000000},
1481                            chapters[i].start, chapters[i].end,
1482                            chapters[i].title);
1483             av_metadata_set2(&chapters[i].chapter->metadata,
1484                              "title", chapters[i].title, 0);
1485             max_start = chapters[i].start;
1486         }
1487
1488     index_list = &matroska->index;
1489     index = index_list->elem;
1490     if (index_list->nb_elem
1491         && index[0].time > 100000000000000/matroska->time_scale) {
1492         av_log(matroska->ctx, AV_LOG_WARNING, "Working around broken index.\n");
1493         index_scale = matroska->time_scale;
1494     }
1495     for (i=0; i<index_list->nb_elem; i++) {
1496         EbmlList *pos_list = &index[i].pos;
1497         MatroskaIndexPos *pos = pos_list->elem;
1498         for (j=0; j<pos_list->nb_elem; j++) {
1499             MatroskaTrack *track = matroska_find_track_by_num(matroska,
1500                                                               pos[j].track);
1501             if (track && track->stream)
1502                 av_add_index_entry(track->stream,
1503                                    pos[j].pos + matroska->segment_start,
1504                                    index[i].time/index_scale, 0, 0,
1505                                    AVINDEX_KEYFRAME);
1506         }
1507     }
1508
1509     matroska_convert_tags(s);
1510
1511     return 0;
1512 }
1513
1514 /*
1515  * Put one packet in an application-supplied AVPacket struct.
1516  * Returns 0 on success or -1 on failure.
1517  */
1518 static int matroska_deliver_packet(MatroskaDemuxContext *matroska,
1519                                    AVPacket *pkt)
1520 {
1521     if (matroska->num_packets > 0) {
1522         memcpy(pkt, matroska->packets[0], sizeof(AVPacket));
1523         av_free(matroska->packets[0]);
1524         if (matroska->num_packets > 1) {
1525             memmove(&matroska->packets[0], &matroska->packets[1],
1526                     (matroska->num_packets - 1) * sizeof(AVPacket *));
1527             matroska->packets =
1528                 av_realloc(matroska->packets, (matroska->num_packets - 1) *
1529                            sizeof(AVPacket *));
1530         } else {
1531             av_freep(&matroska->packets);
1532         }
1533         matroska->num_packets--;
1534         return 0;
1535     }
1536
1537     return -1;
1538 }
1539
1540 /*
1541  * Free all packets in our internal queue.
1542  */
1543 static void matroska_clear_queue(MatroskaDemuxContext *matroska)
1544 {
1545     if (matroska->packets) {
1546         int n;
1547         for (n = 0; n < matroska->num_packets; n++) {
1548             av_free_packet(matroska->packets[n]);
1549             av_free(matroska->packets[n]);
1550         }
1551         av_freep(&matroska->packets);
1552         matroska->num_packets = 0;
1553     }
1554 }
1555
1556 static int matroska_parse_block(MatroskaDemuxContext *matroska, uint8_t *data,
1557                                 int size, int64_t pos, uint64_t cluster_time,
1558                                 uint64_t duration, int is_keyframe,
1559                                 int64_t cluster_pos)
1560 {
1561     uint64_t timecode = AV_NOPTS_VALUE;
1562     MatroskaTrack *track;
1563     int res = 0;
1564     AVStream *st;
1565     AVPacket *pkt;
1566     int16_t block_time;
1567     uint32_t *lace_size = NULL;
1568     int n, flags, laces = 0;
1569     uint64_t num;
1570
1571     if ((n = matroska_ebmlnum_uint(matroska, data, size, &num)) < 0) {
1572         av_log(matroska->ctx, AV_LOG_ERROR, "EBML block data error\n");
1573         return res;
1574     }
1575     data += n;
1576     size -= n;
1577
1578     track = matroska_find_track_by_num(matroska, num);
1579     if (size <= 3 || !track || !track->stream) {
1580         av_log(matroska->ctx, AV_LOG_INFO,
1581                "Invalid stream %"PRIu64" or size %u\n", num, size);
1582         return res;
1583     }
1584     st = track->stream;
1585     if (st->discard >= AVDISCARD_ALL)
1586         return res;
1587     if (duration == AV_NOPTS_VALUE)
1588         duration = track->default_duration / matroska->time_scale;
1589
1590     block_time = AV_RB16(data);
1591     data += 2;
1592     flags = *data++;
1593     size -= 3;
1594     if (is_keyframe == -1)
1595         is_keyframe = flags & 0x80 ? AV_PKT_FLAG_KEY : 0;
1596
1597     if (cluster_time != (uint64_t)-1
1598         && (block_time >= 0 || cluster_time >= -block_time)) {
1599         timecode = cluster_time + block_time;
1600         if (track->type == MATROSKA_TRACK_TYPE_SUBTITLE
1601             && timecode < track->end_timecode)
1602             is_keyframe = 0;  /* overlapping subtitles are not key frame */
1603         if (is_keyframe)
1604             av_add_index_entry(st, cluster_pos, timecode, 0,0,AVINDEX_KEYFRAME);
1605         track->end_timecode = FFMAX(track->end_timecode, timecode+duration);
1606     }
1607
1608     if (matroska->skip_to_keyframe && track->type != MATROSKA_TRACK_TYPE_SUBTITLE) {
1609         if (!is_keyframe || timecode < matroska->skip_to_timecode)
1610             return res;
1611         matroska->skip_to_keyframe = 0;
1612     }
1613
1614     switch ((flags & 0x06) >> 1) {
1615         case 0x0: /* no lacing */
1616             laces = 1;
1617             lace_size = av_mallocz(sizeof(int));
1618             lace_size[0] = size;
1619             break;
1620
1621         case 0x1: /* Xiph lacing */
1622         case 0x2: /* fixed-size lacing */
1623         case 0x3: /* EBML lacing */
1624             assert(size>0); // size <=3 is checked before size-=3 above
1625             laces = (*data) + 1;
1626             data += 1;
1627             size -= 1;
1628             lace_size = av_mallocz(laces * sizeof(int));
1629
1630             switch ((flags & 0x06) >> 1) {
1631                 case 0x1: /* Xiph lacing */ {
1632                     uint8_t temp;
1633                     uint32_t total = 0;
1634                     for (n = 0; res == 0 && n < laces - 1; n++) {
1635                         while (1) {
1636                             if (size == 0) {
1637                                 res = -1;
1638                                 break;
1639                             }
1640                             temp = *data;
1641                             lace_size[n] += temp;
1642                             data += 1;
1643                             size -= 1;
1644                             if (temp != 0xff)
1645                                 break;
1646                         }
1647                         total += lace_size[n];
1648                     }
1649                     lace_size[n] = size - total;
1650                     break;
1651                 }
1652
1653                 case 0x2: /* fixed-size lacing */
1654                     for (n = 0; n < laces; n++)
1655                         lace_size[n] = size / laces;
1656                     break;
1657
1658                 case 0x3: /* EBML lacing */ {
1659                     uint32_t total;
1660                     n = matroska_ebmlnum_uint(matroska, data, size, &num);
1661                     if (n < 0) {
1662                         av_log(matroska->ctx, AV_LOG_INFO,
1663                                "EBML block data error\n");
1664                         break;
1665                     }
1666                     data += n;
1667                     size -= n;
1668                     total = lace_size[0] = num;
1669                     for (n = 1; res == 0 && n < laces - 1; n++) {
1670                         int64_t snum;
1671                         int r;
1672                         r = matroska_ebmlnum_sint(matroska, data, size, &snum);
1673                         if (r < 0) {
1674                             av_log(matroska->ctx, AV_LOG_INFO,
1675                                    "EBML block data error\n");
1676                             break;
1677                         }
1678                         data += r;
1679                         size -= r;
1680                         lace_size[n] = lace_size[n - 1] + snum;
1681                         total += lace_size[n];
1682                     }
1683                     lace_size[n] = size - total;
1684                     break;
1685                 }
1686             }
1687             break;
1688     }
1689
1690     if (res == 0) {
1691         for (n = 0; n < laces; n++) {
1692             if ((st->codec->codec_id == CODEC_ID_RA_288 ||
1693                  st->codec->codec_id == CODEC_ID_COOK ||
1694                  st->codec->codec_id == CODEC_ID_SIPR ||
1695                  st->codec->codec_id == CODEC_ID_ATRAC3) &&
1696                  st->codec->block_align && track->audio.sub_packet_size) {
1697                 int a = st->codec->block_align;
1698                 int sps = track->audio.sub_packet_size;
1699                 int cfs = track->audio.coded_framesize;
1700                 int h = track->audio.sub_packet_h;
1701                 int y = track->audio.sub_packet_cnt;
1702                 int w = track->audio.frame_size;
1703                 int x;
1704
1705                 if (!track->audio.pkt_cnt) {
1706                     if (st->codec->codec_id == CODEC_ID_RA_288)
1707                         for (x=0; x<h/2; x++)
1708                             memcpy(track->audio.buf+x*2*w+y*cfs,
1709                                    data+x*cfs, cfs);
1710                     else if (st->codec->codec_id == CODEC_ID_SIPR)
1711                         memcpy(track->audio.buf + y*w, data, w);
1712                     else
1713                         for (x=0; x<w/sps; x++)
1714                             memcpy(track->audio.buf+sps*(h*x+((h+1)/2)*(y&1)+(y>>1)), data+x*sps, sps);
1715
1716                     if (++track->audio.sub_packet_cnt >= h) {
1717                         if (st->codec->codec_id == CODEC_ID_SIPR)
1718                             ff_rm_reorder_sipr_data(track->audio.buf, h, w);
1719                         track->audio.sub_packet_cnt = 0;
1720                         track->audio.pkt_cnt = h*w / a;
1721                     }
1722                 }
1723                 while (track->audio.pkt_cnt) {
1724                     pkt = av_mallocz(sizeof(AVPacket));
1725                     av_new_packet(pkt, a);
1726                     memcpy(pkt->data, track->audio.buf
1727                            + a * (h*w / a - track->audio.pkt_cnt--), a);
1728                     pkt->pos = pos;
1729                     pkt->stream_index = st->index;
1730                     dynarray_add(&matroska->packets,&matroska->num_packets,pkt);
1731                 }
1732             } else {
1733                 MatroskaTrackEncoding *encodings = track->encodings.elem;
1734                 int offset = 0, pkt_size = lace_size[n];
1735                 uint8_t *pkt_data = data;
1736
1737                 if (pkt_size > size) {
1738                     av_log(matroska->ctx, AV_LOG_ERROR, "Invalid packet size\n");
1739                     break;
1740                 }
1741
1742                 if (encodings && encodings->scope & 1) {
1743                     offset = matroska_decode_buffer(&pkt_data,&pkt_size, track);
1744                     if (offset < 0)
1745                         continue;
1746                 }
1747
1748                 pkt = av_mallocz(sizeof(AVPacket));
1749                 /* XXX: prevent data copy... */
1750                 if (av_new_packet(pkt, pkt_size+offset) < 0) {
1751                     av_free(pkt);
1752                     res = AVERROR(ENOMEM);
1753                     break;
1754                 }
1755                 if (offset)
1756                     memcpy (pkt->data, encodings->compression.settings.data, offset);
1757                 memcpy (pkt->data+offset, pkt_data, pkt_size);
1758
1759                 if (pkt_data != data)
1760                     av_free(pkt_data);
1761
1762                 if (n == 0)
1763                     pkt->flags = is_keyframe;
1764                 pkt->stream_index = st->index;
1765
1766                 if (track->ms_compat)
1767                     pkt->dts = timecode;
1768                 else
1769                     pkt->pts = timecode;
1770                 pkt->pos = pos;
1771                 if (st->codec->codec_id == CODEC_ID_TEXT)
1772                     pkt->convergence_duration = duration;
1773                 else if (track->type != MATROSKA_TRACK_TYPE_SUBTITLE)
1774                     pkt->duration = duration;
1775
1776                 if (st->codec->codec_id == CODEC_ID_SSA)
1777                     matroska_fix_ass_packet(matroska, pkt, duration);
1778
1779                 if (matroska->prev_pkt &&
1780                     timecode != AV_NOPTS_VALUE &&
1781                     matroska->prev_pkt->pts == timecode &&
1782                     matroska->prev_pkt->stream_index == st->index &&
1783                     st->codec->codec_id == CODEC_ID_SSA)
1784                     matroska_merge_packets(matroska->prev_pkt, pkt);
1785                 else {
1786                     dynarray_add(&matroska->packets,&matroska->num_packets,pkt);
1787                     matroska->prev_pkt = pkt;
1788                 }
1789             }
1790
1791             if (timecode != AV_NOPTS_VALUE)
1792                 timecode = duration ? timecode + duration : AV_NOPTS_VALUE;
1793             data += lace_size[n];
1794             size -= lace_size[n];
1795         }
1796     }
1797
1798     av_free(lace_size);
1799     return res;
1800 }
1801
1802 static int matroska_parse_cluster(MatroskaDemuxContext *matroska)
1803 {
1804     MatroskaCluster cluster = { 0 };
1805     EbmlList *blocks_list;
1806     MatroskaBlock *blocks;
1807     int i, res;
1808     int64_t pos = url_ftell(matroska->ctx->pb);
1809     matroska->prev_pkt = NULL;
1810     if (matroska->current_id)
1811         pos -= 4;  /* sizeof the ID which was already read */
1812     res = ebml_parse(matroska, matroska_clusters, &cluster);
1813     blocks_list = &cluster.blocks;
1814     blocks = blocks_list->elem;
1815     for (i=0; i<blocks_list->nb_elem; i++)
1816         if (blocks[i].bin.size > 0 && blocks[i].bin.data) {
1817             int is_keyframe = blocks[i].non_simple ? !blocks[i].reference : -1;
1818             res=matroska_parse_block(matroska,
1819                                      blocks[i].bin.data, blocks[i].bin.size,
1820                                      blocks[i].bin.pos,  cluster.timecode,
1821                                      blocks[i].duration, is_keyframe,
1822                                      pos);
1823         }
1824     ebml_free(matroska_cluster, &cluster);
1825     if (res < 0)  matroska->done = 1;
1826     return res;
1827 }
1828
1829 static int matroska_read_packet(AVFormatContext *s, AVPacket *pkt)
1830 {
1831     MatroskaDemuxContext *matroska = s->priv_data;
1832
1833     while (matroska_deliver_packet(matroska, pkt)) {
1834         if (matroska->done)
1835             return AVERROR_EOF;
1836         matroska_parse_cluster(matroska);
1837     }
1838
1839     return 0;
1840 }
1841
1842 static int matroska_read_seek(AVFormatContext *s, int stream_index,
1843                               int64_t timestamp, int flags)
1844 {
1845     MatroskaDemuxContext *matroska = s->priv_data;
1846     MatroskaTrack *tracks = matroska->tracks.elem;
1847     AVStream *st = s->streams[stream_index];
1848     int i, index, index_sub, index_min;
1849
1850     if (!st->nb_index_entries)
1851         return 0;
1852     timestamp = FFMAX(timestamp, st->index_entries[0].timestamp);
1853
1854     if ((index = av_index_search_timestamp(st, timestamp, flags)) < 0) {
1855         url_fseek(s->pb, st->index_entries[st->nb_index_entries-1].pos, SEEK_SET);
1856         while ((index = av_index_search_timestamp(st, timestamp, flags)) < 0) {
1857             matroska_clear_queue(matroska);
1858             if (matroska_parse_cluster(matroska) < 0)
1859                 break;
1860         }
1861     }
1862
1863     matroska_clear_queue(matroska);
1864     if (index < 0)
1865         return 0;
1866
1867     index_min = index;
1868     for (i=0; i < matroska->tracks.nb_elem; i++) {
1869         tracks[i].end_timecode = 0;
1870         if (tracks[i].type == MATROSKA_TRACK_TYPE_SUBTITLE
1871             && !tracks[i].stream->discard != AVDISCARD_ALL) {
1872             index_sub = av_index_search_timestamp(tracks[i].stream, st->index_entries[index].timestamp, AVSEEK_FLAG_BACKWARD);
1873             if (index_sub >= 0
1874                 && st->index_entries[index_sub].pos < st->index_entries[index_min].pos
1875                 && st->index_entries[index].timestamp - st->index_entries[index_sub].timestamp < 30000000000/matroska->time_scale)
1876                 index_min = index_sub;
1877         }
1878     }
1879
1880     url_fseek(s->pb, st->index_entries[index_min].pos, SEEK_SET);
1881     matroska->skip_to_keyframe = !(flags & AVSEEK_FLAG_ANY);
1882     matroska->skip_to_timecode = st->index_entries[index].timestamp;
1883     matroska->done = 0;
1884     av_update_cur_dts(s, st, st->index_entries[index].timestamp);
1885     return 0;
1886 }
1887
1888 static int matroska_read_close(AVFormatContext *s)
1889 {
1890     MatroskaDemuxContext *matroska = s->priv_data;
1891     MatroskaTrack *tracks = matroska->tracks.elem;
1892     int n;
1893
1894     matroska_clear_queue(matroska);
1895
1896     for (n=0; n < matroska->tracks.nb_elem; n++)
1897         if (tracks[n].type == MATROSKA_TRACK_TYPE_AUDIO)
1898             av_free(tracks[n].audio.buf);
1899     ebml_free(matroska_segment, matroska);
1900
1901     return 0;
1902 }
1903
1904 AVInputFormat matroska_demuxer = {
1905     "matroska,webm",
1906     NULL_IF_CONFIG_SMALL("Matroska/WebM file format"),
1907     sizeof(MatroskaDemuxContext),
1908     matroska_probe,
1909     matroska_read_header,
1910     matroska_read_packet,
1911     matroska_read_close,
1912     matroska_read_seek,
1913     .metadata_conv = ff_mkv_metadata_conv,
1914 };