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     EBML_TYPE_COUNT
  62 } EbmlType;
  63
  64 typedef const struct EbmlSyntax {
  65     uint32_t id;
  66     EbmlType type;
  67     int list_elem_size;
  68     int data_offset;
  69     union {
  70         uint64_t    u;
  71         double      f;
  72         const char *s;
  73         const struct EbmlSyntax *n;
  74     } def;
  75 } EbmlSyntax;
  76
  77 typedef struct {
  78     int nb_elem;
  79     void *elem;
  80 } EbmlList;
  81
  82 typedef struct {
  83     int      size;
  84     uint8_t *data;
  85     int64_t  pos;
  86 } EbmlBin;
  87
  88 typedef struct {
  89     uint64_t version;
  90     uint64_t max_size;
  91     uint64_t id_length;
  92     char    *doctype;
  93     uint64_t doctype_version;
  94 } Ebml;
  95
  96 typedef struct {
  97     uint64_t algo;
  98     EbmlBin  settings;
  99 } MatroskaTrackCompression;
 100
 101 typedef struct {
 102     uint64_t scope;
 103     uint64_t type;
 104     MatroskaTrackCompression compression;
 105 } MatroskaTrackEncoding;
 106
 107 typedef struct {
 108     double   frame_rate;
 109     uint64_t display_width;
 110     uint64_t display_height;
 111     uint64_t pixel_width;
 112     uint64_t pixel_height;
 113     uint64_t fourcc;
 114 } MatroskaTrackVideo;
 115
 116 typedef struct {
 117     double   samplerate;
 118     double   out_samplerate;
 119     uint64_t bitdepth;
 120     uint64_t channels;
 121
 122     /* real audio header (extracted from extradata) */
 123     int      coded_framesize;
 124     int      sub_packet_h;
 125     int      frame_size;
 126     int      sub_packet_size;
 127     int      sub_packet_cnt;
 128     int      pkt_cnt;
 129     uint8_t *buf;
 130 } MatroskaTrackAudio;
 131
 132 typedef struct {
 133     uint64_t num;
 134     uint64_t uid;
 135     uint64_t type;
 136     char    *name;
 137     char    *codec_id;
 138     EbmlBin  codec_priv;
 139     char    *language;
 140     double time_scale;
 141     uint64_t default_duration;
 142     uint64_t flag_default;
 143     uint64_t flag_forced;
 144     MatroskaTrackVideo video;
 145     MatroskaTrackAudio audio;
 146     EbmlList encodings;
 147
 148     AVStream *stream;
 149     int64_t end_timecode;
 150     int ms_compat;
 151 } MatroskaTrack;
 152
 153 typedef struct {
 154     uint64_t uid;
 155     char *filename;
 156     char *mime;
 157     EbmlBin bin;
 158
 159     AVStream *stream;
 160 } MatroskaAttachement;
 161
 162 typedef struct {
 163     uint64_t start;
 164     uint64_t end;
 165     uint64_t uid;
 166     char    *title;
 167
 168     AVChapter *chapter;
 169 } MatroskaChapter;
 170
 171 typedef struct {
 172     uint64_t track;
 173     uint64_t pos;
 174 } MatroskaIndexPos;
 175
 176 typedef struct {
 177     uint64_t time;
 178     EbmlList pos;
 179 } MatroskaIndex;
 180
 181 typedef struct {
 182     char *name;
 183     char *string;
 184     char *lang;
 185     uint64_t def;
 186     EbmlList sub;
 187 } MatroskaTag;
 188
 189 typedef struct {
 190     char    *type;
 191     uint64_t typevalue;
 192     uint64_t trackuid;
 193     uint64_t chapteruid;
 194     uint64_t attachuid;
 195 } MatroskaTagTarget;
 196
 197 typedef struct {
 198     MatroskaTagTarget target;
 199     EbmlList tag;
 200 } MatroskaTags;
 201
 202 typedef struct {
 203     uint64_t id;
 204     uint64_t pos;
 205 } MatroskaSeekhead;
 206
 207 typedef struct {
 208     uint64_t start;
 209     uint64_t length;
 210 } MatroskaLevel;
 211
 212 typedef struct {
 213     AVFormatContext *ctx;
 214
 215     /* EBML stuff */
 216     int num_levels;
 217     MatroskaLevel levels[EBML_MAX_DEPTH];
 218     int level_up;
 219     uint32_t current_id;
 220
 221     uint64_t time_scale;
 222     double   duration;
 223     char    *title;
 224     EbmlList tracks;
 225     EbmlList attachments;
 226     EbmlList chapters;
 227     EbmlList index;
 228     EbmlList tags;
 229     EbmlList seekhead;
 230
 231     /* byte position of the segment inside the stream */
 232     int64_t segment_start;
 233
 234     /* the packet queue */
 235     AVPacket **packets;
 236     int num_packets;
 237     AVPacket *prev_pkt;
 238
 239     int done;
 240
 241     /* What to skip before effectively reading a packet. */
 242     int skip_to_keyframe;
 243     uint64_t skip_to_timecode;
 244 } MatroskaDemuxContext;
 245
 246 typedef struct {
 247     uint64_t duration;
 248     int64_t  reference;
 249     uint64_t non_simple;
 250     EbmlBin  bin;
 251 } MatroskaBlock;
 252
 253 typedef struct {
 254     uint64_t timecode;
 255     EbmlList blocks;
 256 } MatroskaCluster;
 257
 258 static EbmlSyntax ebml_header[] = {
 259     { EBML_ID_EBMLREADVERSION,        EBML_UINT, 0, offsetof(Ebml,version), {.u=EBML_VERSION} },
 260     { EBML_ID_EBMLMAXSIZELENGTH,      EBML_UINT, 0, offsetof(Ebml,max_size), {.u=8} },
 261     { EBML_ID_EBMLMAXIDLENGTH,        EBML_UINT, 0, offsetof(Ebml,id_length), {.u=4} },
 262     { EBML_ID_DOCTYPE,                EBML_STR,  0, offsetof(Ebml,doctype), {.s="(none)"} },
 263     { EBML_ID_DOCTYPEREADVERSION,     EBML_UINT, 0, offsetof(Ebml,doctype_version), {.u=1} },
 264     { EBML_ID_EBMLVERSION,            EBML_NONE },
 265     { EBML_ID_DOCTYPEVERSION,         EBML_NONE },
 266     { 0 }
 267 };
 268
 269 static EbmlSyntax ebml_syntax[] = {
 270     { EBML_ID_HEADER,                 EBML_NEST, 0, 0, {.n=ebml_header} },
 271     { 0 }
 272 };
 273
 274 static EbmlSyntax matroska_info[] = {
 275     { MATROSKA_ID_TIMECODESCALE,      EBML_UINT,  0, offsetof(MatroskaDemuxContext,time_scale), {.u=1000000} },
 276     { MATROSKA_ID_DURATION,           EBML_FLOAT, 0, offsetof(MatroskaDemuxContext,duration) },
 277     { MATROSKA_ID_TITLE,              EBML_UTF8,  0, offsetof(MatroskaDemuxContext,title) },
 278     { MATROSKA_ID_WRITINGAPP,         EBML_NONE },
 279     { MATROSKA_ID_MUXINGAPP,          EBML_NONE },
 280     { MATROSKA_ID_DATEUTC,            EBML_NONE },
 281     { MATROSKA_ID_SEGMENTUID,         EBML_NONE },
 282     { 0 }
 283 };
 284
 285 static EbmlSyntax matroska_track_video[] = {
 286     { MATROSKA_ID_VIDEOFRAMERATE,     EBML_FLOAT,0, offsetof(MatroskaTrackVideo,frame_rate) },
 287     { MATROSKA_ID_VIDEODISPLAYWIDTH,  EBML_UINT, 0, offsetof(MatroskaTrackVideo,display_width) },
 288     { MATROSKA_ID_VIDEODISPLAYHEIGHT, EBML_UINT, 0, offsetof(MatroskaTrackVideo,display_height) },
 289     { MATROSKA_ID_VIDEOPIXELWIDTH,    EBML_UINT, 0, offsetof(MatroskaTrackVideo,pixel_width) },
 290     { MATROSKA_ID_VIDEOPIXELHEIGHT,   EBML_UINT, 0, offsetof(MatroskaTrackVideo,pixel_height) },
 291     { MATROSKA_ID_VIDEOCOLORSPACE,    EBML_UINT, 0, offsetof(MatroskaTrackVideo,fourcc) },
 292     { MATROSKA_ID_VIDEOPIXELCROPB,    EBML_NONE },
 293     { MATROSKA_ID_VIDEOPIXELCROPT,    EBML_NONE },
 294     { MATROSKA_ID_VIDEOPIXELCROPL,    EBML_NONE },
 295     { MATROSKA_ID_VIDEOPIXELCROPR,    EBML_NONE },
 296     { MATROSKA_ID_VIDEODISPLAYUNIT,   EBML_NONE },
 297     { MATROSKA_ID_VIDEOFLAGINTERLACED,EBML_NONE },
 298     { MATROSKA_ID_VIDEOSTEREOMODE,    EBML_NONE },
 299     { MATROSKA_ID_VIDEOASPECTRATIO,   EBML_NONE },
 300     { 0 }
 301 };
 302
 303 static EbmlSyntax matroska_track_audio[] = {
 304     { MATROSKA_ID_AUDIOSAMPLINGFREQ,  EBML_FLOAT,0, offsetof(MatroskaTrackAudio,samplerate), {.f=8000.0} },
 305     { MATROSKA_ID_AUDIOOUTSAMPLINGFREQ,EBML_FLOAT,0,offsetof(MatroskaTrackAudio,out_samplerate) },
 306     { MATROSKA_ID_AUDIOBITDEPTH,      EBML_UINT, 0, offsetof(MatroskaTrackAudio,bitdepth) },
 307     { MATROSKA_ID_AUDIOCHANNELS,      EBML_UINT, 0, offsetof(MatroskaTrackAudio,channels), {.u=1} },
 308     { 0 }
 309 };
 310
 311 static EbmlSyntax matroska_track_encoding_compression[] = {
 312     { MATROSKA_ID_ENCODINGCOMPALGO,   EBML_UINT, 0, offsetof(MatroskaTrackCompression,algo), {.u=0} },
 313     { MATROSKA_ID_ENCODINGCOMPSETTINGS,EBML_BIN, 0, offsetof(MatroskaTrackCompression,settings) },
 314     { 0 }
 315 };
 316
 317 static EbmlSyntax matroska_track_encoding[] = {
 318     { MATROSKA_ID_ENCODINGSCOPE,      EBML_UINT, 0, offsetof(MatroskaTrackEncoding,scope), {.u=1} },
 319     { MATROSKA_ID_ENCODINGTYPE,       EBML_UINT, 0, offsetof(MatroskaTrackEncoding,type), {.u=0} },
 320     { MATROSKA_ID_ENCODINGCOMPRESSION,EBML_NEST, 0, offsetof(MatroskaTrackEncoding,compression), {.n=matroska_track_encoding_compression} },
 321     { MATROSKA_ID_ENCODINGORDER,      EBML_NONE },
 322     { 0 }
 323 };
 324
 325 static EbmlSyntax matroska_track_encodings[] = {
 326     { MATROSKA_ID_TRACKCONTENTENCODING, EBML_NEST, sizeof(MatroskaTrackEncoding), offsetof(MatroskaTrack,encodings), {.n=matroska_track_encoding} },
 327     { 0 }
 328 };
 329
 330 static EbmlSyntax matroska_track[] = {
 331     { MATROSKA_ID_TRACKNUMBER,          EBML_UINT, 0, offsetof(MatroskaTrack,num) },
 332     { MATROSKA_ID_TRACKNAME,            EBML_UTF8, 0, offsetof(MatroskaTrack,name) },
 333     { MATROSKA_ID_TRACKUID,             EBML_UINT, 0, offsetof(MatroskaTrack,uid) },
 334     { MATROSKA_ID_TRACKTYPE,            EBML_UINT, 0, offsetof(MatroskaTrack,type) },
 335     { MATROSKA_ID_CODECID,              EBML_STR,  0, offsetof(MatroskaTrack,codec_id) },
 336     { MATROSKA_ID_CODECPRIVATE,         EBML_BIN,  0, offsetof(MatroskaTrack,codec_priv) },
 337     { MATROSKA_ID_TRACKLANGUAGE,        EBML_UTF8, 0, offsetof(MatroskaTrack,language), {.s="eng"} },
 338     { MATROSKA_ID_TRACKDEFAULTDURATION, EBML_UINT, 0, offsetof(MatroskaTrack,default_duration) },
 339     { MATROSKA_ID_TRACKTIMECODESCALE,   EBML_FLOAT,0, offsetof(MatroskaTrack,time_scale), {.f=1.0} },
 340     { MATROSKA_ID_TRACKFLAGDEFAULT,     EBML_UINT, 0, offsetof(MatroskaTrack,flag_default), {.u=1} },
 341     { MATROSKA_ID_TRACKFLAGFORCED,      EBML_UINT, 0, offsetof(MatroskaTrack,flag_forced), {.u=0} },
 342     { MATROSKA_ID_TRACKVIDEO,           EBML_NEST, 0, offsetof(MatroskaTrack,video), {.n=matroska_track_video} },
 343     { MATROSKA_ID_TRACKAUDIO,           EBML_NEST, 0, offsetof(MatroskaTrack,audio), {.n=matroska_track_audio} },
 344     { MATROSKA_ID_TRACKCONTENTENCODINGS,EBML_NEST, 0, 0, {.n=matroska_track_encodings} },
 345     { MATROSKA_ID_TRACKFLAGENABLED,     EBML_NONE },
 346     { MATROSKA_ID_TRACKFLAGLACING,      EBML_NONE },
 347     { MATROSKA_ID_CODECNAME,            EBML_NONE },
 348     { MATROSKA_ID_CODECDECODEALL,       EBML_NONE },
 349     { MATROSKA_ID_CODECINFOURL,         EBML_NONE },
 350     { MATROSKA_ID_CODECDOWNLOADURL,     EBML_NONE },
 351     { MATROSKA_ID_TRACKMINCACHE,        EBML_NONE },
 352     { MATROSKA_ID_TRACKMAXCACHE,        EBML_NONE },
 353     { MATROSKA_ID_TRACKMAXBLKADDID,     EBML_NONE },
 354     { 0 }
 355 };
 356
 357 static EbmlSyntax matroska_tracks[] = {
 358     { MATROSKA_ID_TRACKENTRY,         EBML_NEST, sizeof(MatroskaTrack), offsetof(MatroskaDemuxContext,tracks), {.n=matroska_track} },
 359     { 0 }
 360 };
 361
 362 static EbmlSyntax matroska_attachment[] = {
 363     { MATROSKA_ID_FILEUID,            EBML_UINT, 0, offsetof(MatroskaAttachement,uid) },
 364     { MATROSKA_ID_FILENAME,           EBML_UTF8, 0, offsetof(MatroskaAttachement,filename) },
 365     { MATROSKA_ID_FILEMIMETYPE,       EBML_STR,  0, offsetof(MatroskaAttachement,mime) },
 366     { MATROSKA_ID_FILEDATA,           EBML_BIN,  0, offsetof(MatroskaAttachement,bin) },
 367     { MATROSKA_ID_FILEDESC,           EBML_NONE },
 368     { 0 }
 369 };
 370
 371 static EbmlSyntax matroska_attachments[] = {
 372     { MATROSKA_ID_ATTACHEDFILE,       EBML_NEST, sizeof(MatroskaAttachement), offsetof(MatroskaDemuxContext,attachments), {.n=matroska_attachment} },
 373     { 0 }
 374 };
 375
 376 static EbmlSyntax matroska_chapter_display[] = {
 377     { MATROSKA_ID_CHAPSTRING,         EBML_UTF8, 0, offsetof(MatroskaChapter,title) },
 378     { MATROSKA_ID_CHAPLANG,           EBML_NONE },
 379     { 0 }
 380 };
 381
 382 static EbmlSyntax matroska_chapter_entry[] = {
 383     { MATROSKA_ID_CHAPTERTIMESTART,   EBML_UINT, 0, offsetof(MatroskaChapter,start), {.u=AV_NOPTS_VALUE} },
 384     { MATROSKA_ID_CHAPTERTIMEEND,     EBML_UINT, 0, offsetof(MatroskaChapter,end), {.u=AV_NOPTS_VALUE} },
 385     { MATROSKA_ID_CHAPTERUID,         EBML_UINT, 0, offsetof(MatroskaChapter,uid) },
 386     { MATROSKA_ID_CHAPTERDISPLAY,     EBML_NEST, 0, 0, {.n=matroska_chapter_display} },
 387     { MATROSKA_ID_CHAPTERFLAGHIDDEN,  EBML_NONE },
 388     { MATROSKA_ID_CHAPTERFLAGENABLED, EBML_NONE },
 389     { MATROSKA_ID_CHAPTERPHYSEQUIV,   EBML_NONE },
 390     { MATROSKA_ID_CHAPTERATOM,        EBML_NONE },
 391     { 0 }
 392 };
 393
 394 static EbmlSyntax matroska_chapter[] = {
 395     { MATROSKA_ID_CHAPTERATOM,        EBML_NEST, sizeof(MatroskaChapter), offsetof(MatroskaDemuxContext,chapters), {.n=matroska_chapter_entry} },
 396     { MATROSKA_ID_EDITIONUID,         EBML_NONE },
 397     { MATROSKA_ID_EDITIONFLAGHIDDEN,  EBML_NONE },
 398     { MATROSKA_ID_EDITIONFLAGDEFAULT, EBML_NONE },
 399     { MATROSKA_ID_EDITIONFLAGORDERED, EBML_NONE },
 400     { 0 }
 401 };
 402
 403 static EbmlSyntax matroska_chapters[] = {
 404     { MATROSKA_ID_EDITIONENTRY,       EBML_NEST, 0, 0, {.n=matroska_chapter} },
 405     { 0 }
 406 };
 407
 408 static EbmlSyntax matroska_index_pos[] = {
 409     { MATROSKA_ID_CUETRACK,           EBML_UINT, 0, offsetof(MatroskaIndexPos,track) },
 410     { MATROSKA_ID_CUECLUSTERPOSITION, EBML_UINT, 0, offsetof(MatroskaIndexPos,pos)   },
 411     { MATROSKA_ID_CUEBLOCKNUMBER,     EBML_NONE },
 412     { 0 }
 413 };
 414
 415 static EbmlSyntax matroska_index_entry[] = {
 416     { MATROSKA_ID_CUETIME,            EBML_UINT, 0, offsetof(MatroskaIndex,time) },
 417     { MATROSKA_ID_CUETRACKPOSITION,   EBML_NEST, sizeof(MatroskaIndexPos), offsetof(MatroskaIndex,pos), {.n=matroska_index_pos} },
 418     { 0 }
 419 };
 420
 421 static EbmlSyntax matroska_index[] = {
 422     { MATROSKA_ID_POINTENTRY,         EBML_NEST, sizeof(MatroskaIndex), offsetof(MatroskaDemuxContext,index), {.n=matroska_index_entry} },
 423     { 0 }
 424 };
 425
 426 static EbmlSyntax matroska_simpletag[] = {
 427     { MATROSKA_ID_TAGNAME,            EBML_UTF8, 0, offsetof(MatroskaTag,name) },
 428     { MATROSKA_ID_TAGSTRING,          EBML_UTF8, 0, offsetof(MatroskaTag,string) },
 429     { MATROSKA_ID_TAGLANG,            EBML_STR,  0, offsetof(MatroskaTag,lang), {.s="und"} },
 430     { MATROSKA_ID_TAGDEFAULT,         EBML_UINT, 0, offsetof(MatroskaTag,def) },
 431     { MATROSKA_ID_TAGDEFAULT_BUG,     EBML_UINT, 0, offsetof(MatroskaTag,def) },
 432     { MATROSKA_ID_SIMPLETAG,          EBML_NEST, sizeof(MatroskaTag), offsetof(MatroskaTag,sub), {.n=matroska_simpletag} },
 433     { 0 }
 434 };
 435
 436 static EbmlSyntax matroska_tagtargets[] = {
 437     { MATROSKA_ID_TAGTARGETS_TYPE,      EBML_STR,  0, offsetof(MatroskaTagTarget,type) },
 438     { MATROSKA_ID_TAGTARGETS_TYPEVALUE, EBML_UINT, 0, offsetof(MatroskaTagTarget,typevalue), {.u=50} },
 439     { MATROSKA_ID_TAGTARGETS_TRACKUID,  EBML_UINT, 0, offsetof(MatroskaTagTarget,trackuid) },
 440     { MATROSKA_ID_TAGTARGETS_CHAPTERUID,EBML_UINT, 0, offsetof(MatroskaTagTarget,chapteruid) },
 441     { MATROSKA_ID_TAGTARGETS_ATTACHUID, EBML_UINT, 0, offsetof(MatroskaTagTarget,attachuid) },
 442     { 0 }
 443 };
 444
 445 static EbmlSyntax matroska_tag[] = {
 446     { MATROSKA_ID_SIMPLETAG,          EBML_NEST, sizeof(MatroskaTag), offsetof(MatroskaTags,tag), {.n=matroska_simpletag} },
 447     { MATROSKA_ID_TAGTARGETS,         EBML_NEST, 0, offsetof(MatroskaTags,target), {.n=matroska_tagtargets} },
 448     { 0 }
 449 };
 450
 451 static EbmlSyntax matroska_tags[] = {
 452     { MATROSKA_ID_TAG,                EBML_NEST, sizeof(MatroskaTags), offsetof(MatroskaDemuxContext,tags), {.n=matroska_tag} },
 453     { 0 }
 454 };
 455
 456 static EbmlSyntax matroska_seekhead_entry[] = {
 457     { MATROSKA_ID_SEEKID,             EBML_UINT, 0, offsetof(MatroskaSeekhead,id) },
 458     { MATROSKA_ID_SEEKPOSITION,       EBML_UINT, 0, offsetof(MatroskaSeekhead,pos), {.u=-1} },
 459     { 0 }
 460 };
 461
 462 static EbmlSyntax matroska_seekhead[] = {
 463     { MATROSKA_ID_SEEKENTRY,          EBML_NEST, sizeof(MatroskaSeekhead), offsetof(MatroskaDemuxContext,seekhead), {.n=matroska_seekhead_entry} },
 464     { 0 }
 465 };
 466
 467 static EbmlSyntax matroska_segment[] = {
 468     { MATROSKA_ID_INFO,           EBML_NEST, 0, 0, {.n=matroska_info       } },
 469     { MATROSKA_ID_TRACKS,         EBML_NEST, 0, 0, {.n=matroska_tracks     } },
 470     { MATROSKA_ID_ATTACHMENTS,    EBML_NEST, 0, 0, {.n=matroska_attachments} },
 471     { MATROSKA_ID_CHAPTERS,       EBML_NEST, 0, 0, {.n=matroska_chapters   } },
 472     { MATROSKA_ID_CUES,           EBML_NEST, 0, 0, {.n=matroska_index      } },
 473     { MATROSKA_ID_TAGS,           EBML_NEST, 0, 0, {.n=matroska_tags       } },
 474     { MATROSKA_ID_SEEKHEAD,       EBML_NEST, 0, 0, {.n=matroska_seekhead   } },
 475     { MATROSKA_ID_CLUSTER,        EBML_STOP },
 476     { 0 }
 477 };
 478
 479 static EbmlSyntax matroska_segments[] = {
 480     { MATROSKA_ID_SEGMENT,        EBML_NEST, 0, 0, {.n=matroska_segment    } },
 481     { 0 }
 482 };
 483
 484 static EbmlSyntax matroska_blockgroup[] = {
 485     { MATROSKA_ID_BLOCK,          EBML_BIN,  0, offsetof(MatroskaBlock,bin) },
 486     { MATROSKA_ID_SIMPLEBLOCK,    EBML_BIN,  0, offsetof(MatroskaBlock,bin) },
 487     { MATROSKA_ID_BLOCKDURATION,  EBML_UINT, 0, offsetof(MatroskaBlock,duration), {.u=AV_NOPTS_VALUE} },
 488     { MATROSKA_ID_BLOCKREFERENCE, EBML_UINT, 0, offsetof(MatroskaBlock,reference) },
 489     { 1,                          EBML_UINT, 0, offsetof(MatroskaBlock,non_simple), {.u=1} },
 490     { 0 }
 491 };
 492
 493 static EbmlSyntax matroska_cluster[] = {
 494     { MATROSKA_ID_CLUSTERTIMECODE,EBML_UINT,0, offsetof(MatroskaCluster,timecode) },
 495     { MATROSKA_ID_BLOCKGROUP,     EBML_NEST, sizeof(MatroskaBlock), offsetof(MatroskaCluster,blocks), {.n=matroska_blockgroup} },
 496     { MATROSKA_ID_SIMPLEBLOCK,    EBML_PASS, sizeof(MatroskaBlock), offsetof(MatroskaCluster,blocks), {.n=matroska_blockgroup} },
 497     { MATROSKA_ID_CLUSTERPOSITION,EBML_NONE },
 498     { MATROSKA_ID_CLUSTERPREVSIZE,EBML_NONE },
 499     { 0 }
 500 };
 501
 502 static EbmlSyntax matroska_clusters[] = {
 503     { MATROSKA_ID_CLUSTER,        EBML_NEST, 0, 0, {.n=matroska_cluster} },
 504     { MATROSKA_ID_INFO,           EBML_NONE },
 505     { MATROSKA_ID_CUES,           EBML_NONE },
 506     { MATROSKA_ID_TAGS,           EBML_NONE },
 507     { MATROSKA_ID_SEEKHEAD,       EBML_NONE },
 508     { 0 }
 509 };
 510
 511 static const char *matroska_doctypes[] = { "matroska", "webm" };
 512
 513 /*
 514  * Return: Whether we reached the end of a level in the hierarchy or not.
 515  */
 516 static int ebml_level_end(MatroskaDemuxContext *matroska)
 517 {
 518     ByteIOContext *pb = matroska->ctx->pb;
 519     int64_t pos = url_ftell(pb);
 520
 521     if (matroska->num_levels > 0) {
 522         MatroskaLevel *level = &matroska->levels[matroska->num_levels - 1];
 523         if (pos - level->start >= level->length || matroska->current_id) {
 524             matroska->num_levels--;
 525             return 1;
 526         }
 527     }
 528     return 0;
 529 }
 530
 531 /*
 532  * Read: an "EBML number", which is defined as a variable-length
 533  * array of bytes. The first byte indicates the length by giving a
 534  * number of 0-bits followed by a one. The position of the first
 535  * "one" bit inside the first byte indicates the length of this
 536  * number.
 537  * Returns: number of bytes read, < 0 on error
 538  */
 539 static int ebml_read_num(MatroskaDemuxContext *matroska, ByteIOContext *pb,
 540                          int max_size, uint64_t *number)
 541 {
 542     int read = 1, n = 1;
 543     uint64_t total = 0;
 544
 545     /* The first byte tells us the length in bytes - get_byte() can normally
 546      * return 0, but since that's not a valid first ebmlID byte, we can
 547      * use it safely here to catch EOS. */
 548     if (!(total = get_byte(pb))) {
 549         /* we might encounter EOS here */
 550         if (!url_feof(pb)) {
 551             int64_t pos = url_ftell(pb);
 552             av_log(matroska->ctx, AV_LOG_ERROR,
 553                    "Read error at pos. %"PRIu64" (0x%"PRIx64")\n",
 554                    pos, pos);
 555         }
 556         return AVERROR(EIO); /* EOS or actual I/O error */
 557     }
 558
 559     /* get the length of the EBML number */
 560     read = 8 - ff_log2_tab[total];
 561     if (read > max_size) {
 562         int64_t pos = url_ftell(pb) - 1;
 563         av_log(matroska->ctx, AV_LOG_ERROR,
 564                "Invalid EBML number size tag 0x%02x at pos %"PRIu64" (0x%"PRIx64")\n",
 565                (uint8_t) total, pos, pos);
 566         return AVERROR_INVALIDDATA;
 567     }
 568
 569     /* read out length */
 570     total ^= 1 << ff_log2_tab[total];
 571     while (n++ < read)
 572         total = (total << 8) | get_byte(pb);
 573
 574     *number = total;
 575
 576     return read;
 577 }
 578
 579 /**
 580  * Read a EBML length value.
 581  * This needs special handling for the "unknown length" case which has multiple
 582  * encodings.
 583  */
 584 static int ebml_read_length(MatroskaDemuxContext *matroska, ByteIOContext *pb,
 585                             uint64_t *number)
 586 {
 587     int res = ebml_read_num(matroska, pb, 8, number);
 588     if (res > 0 && *number + 1 == 1ULL << (7 * res))
 589         *number = 0xffffffffffffffULL;
 590     return res;
 591 }
 592
 593 /*
 594  * Read the next element as an unsigned int.
 595  * 0 is success, < 0 is failure.
 596  */
 597 static int ebml_read_uint(ByteIOContext *pb, int size, uint64_t *num)
 598 {
 599     int n = 0;
 600
 601     if (size > 8)
 602         return AVERROR_INVALIDDATA;
 603
 604     /* big-endian ordering; build up number */
 605     *num = 0;
 606     while (n++ < size)
 607         *num = (*num << 8) | get_byte(pb);
 608
 609     return 0;
 610 }
 611
 612 /*
 613  * Read the next element as a float.
 614  * 0 is success, < 0 is failure.
 615  */
 616 static int ebml_read_float(ByteIOContext *pb, int size, double *num)
 617 {
 618     if (size == 0) {
 619         *num = 0;
 620     } else if (size == 4) {
 621         *num= av_int2flt(get_be32(pb));
 622     } else if(size==8){
 623         *num= av_int2dbl(get_be64(pb));
 624     } else
 625         return AVERROR_INVALIDDATA;
 626
 627     return 0;
 628 }
 629
 630 /*
 631  * Read the next element as an ASCII string.
 632  * 0 is success, < 0 is failure.
 633  */
 634 static int ebml_read_ascii(ByteIOContext *pb, int size, char **str)
 635 {
 636     av_free(*str);
 637     /* EBML strings are usually not 0-terminated, so we allocate one
 638      * byte more, read the string and NULL-terminate it ourselves. */
 639     if (!(*str = av_malloc(size + 1)))
 640         return AVERROR(ENOMEM);
 641     if (get_buffer(pb, (uint8_t *) *str, size) != size) {
 642         av_freep(str);
 643         return AVERROR(EIO);
 644     }
 645     (*str)[size] = '\0';
 646
 647     return 0;
 648 }
 649
 650 /*
 651  * Read the next element as binary data.
 652  * 0 is success, < 0 is failure.
 653  */
 654 static int ebml_read_binary(ByteIOContext *pb, int length, EbmlBin *bin)
 655 {
 656     av_free(bin->data);
 657     if (!(bin->data = av_malloc(length)))
 658         return AVERROR(ENOMEM);
 659
 660     bin->size = length;
 661     bin->pos  = url_ftell(pb);
 662     if (get_buffer(pb, bin->data, length) != length) {
 663         av_freep(&bin->data);
 664         return AVERROR(EIO);
 665     }
 666
 667     return 0;
 668 }
 669
 670 /*
 671  * Read the next element, but only the header. The contents
 672  * are supposed to be sub-elements which can be read separately.
 673  * 0 is success, < 0 is failure.
 674  */
 675 static int ebml_read_master(MatroskaDemuxContext *matroska, uint64_t length)
 676 {
 677     ByteIOContext *pb = matroska->ctx->pb;
 678     MatroskaLevel *level;
 679
 680     if (matroska->num_levels >= EBML_MAX_DEPTH) {
 681         av_log(matroska->ctx, AV_LOG_ERROR,
 682                "File moves beyond max. allowed depth (%d)\n", EBML_MAX_DEPTH);
 683         return AVERROR(ENOSYS);
 684     }
 685
 686     level = &matroska->levels[matroska->num_levels++];
 687     level->start = url_ftell(pb);
 688     level->length = length;
 689
 690     return 0;
 691 }
 692
 693 /*
 694  * Read signed/unsigned "EBML" numbers.
 695  * Return: number of bytes processed, < 0 on error
 696  */
 697 static int matroska_ebmlnum_uint(MatroskaDemuxContext *matroska,
 698                                  uint8_t *data, uint32_t size, uint64_t *num)
 699 {
 700     ByteIOContext pb;
 701     init_put_byte(&pb, data, size, 0, NULL, NULL, NULL, NULL);
 702     return ebml_read_num(matroska, &pb, FFMIN(size, 8), num);
 703 }
 704
 705 /*
 706  * Same as above, but signed.
 707  */
 708 static int matroska_ebmlnum_sint(MatroskaDemuxContext *matroska,
 709                                  uint8_t *data, uint32_t size, int64_t *num)
 710 {
 711     uint64_t unum;
 712     int res;
 713
 714     /* read as unsigned number first */
 715     if ((res = matroska_ebmlnum_uint(matroska, data, size, &unum)) < 0)
 716         return res;
 717
 718     /* make signed (weird way) */
 719     *num = unum - ((1LL << (7*res - 1)) - 1);
 720
 721     return res;
 722 }
 723
 724 static int ebml_parse_elem(MatroskaDemuxContext *matroska,
 725                            EbmlSyntax *syntax, void *data);
 726
 727 static int ebml_parse_id(MatroskaDemuxContext *matroska, EbmlSyntax *syntax,
 728                          uint32_t id, void *data)
 729 {
 730     int i;
 731     for (i=0; syntax[i].id; i++)
 732         if (id == syntax[i].id)
 733             break;
 734     if (!syntax[i].id && id == MATROSKA_ID_CLUSTER &&
 735         matroska->num_levels > 0 &&
 736         matroska->levels[matroska->num_levels-1].length == 0xffffffffffffff)
 737         return 0;  // we reached the end of an unknown size cluster
 738     if (!syntax[i].id && id != EBML_ID_VOID && id != EBML_ID_CRC32)
 739         av_log(matroska->ctx, AV_LOG_INFO, "Unknown entry 0x%X\n", id);
 740     return ebml_parse_elem(matroska, &syntax[i], data);
 741 }
 742
 743 static int ebml_parse(MatroskaDemuxContext *matroska, EbmlSyntax *syntax,
 744                       void *data)
 745 {
 746     if (!matroska->current_id) {
 747         uint64_t id;
 748         int res = ebml_read_num(matroska, matroska->ctx->pb, 4, &id);
 749         if (res < 0)
 750             return res;
 751         matroska->current_id = id | 1 << 7*res;
 752     }
 753     return ebml_parse_id(matroska, syntax, matroska->current_id, data);
 754 }
 755
 756 static int ebml_parse_nest(MatroskaDemuxContext *matroska, EbmlSyntax *syntax,
 757                            void *data)
 758 {
 759     int i, res = 0;
 760
 761     for (i=0; syntax[i].id; i++)
 762         switch (syntax[i].type) {
 763         case EBML_UINT:
 764             *(uint64_t *)((char *)data+syntax[i].data_offset) = syntax[i].def.u;
 765             break;
 766         case EBML_FLOAT:
 767             *(double   *)((char *)data+syntax[i].data_offset) = syntax[i].def.f;
 768             break;
 769         case EBML_STR:
 770         case EBML_UTF8:
 771             *(char    **)((char *)data+syntax[i].data_offset) = av_strdup(syntax[i].def.s);
 772             break;
 773         }
 774
 775     while (!res && !ebml_level_end(matroska))
 776         res = ebml_parse(matroska, syntax, data);
 777
 778     return res;
 779 }
 780
 781 static int ebml_parse_elem(MatroskaDemuxContext *matroska,
 782                            EbmlSyntax *syntax, void *data)
 783 {
 784     static const uint64_t max_lengths[EBML_TYPE_COUNT] = {
 785         [EBML_UINT]  = 8,
 786         [EBML_FLOAT] = 8,
 787         // max. 16 MB for strings
 788         [EBML_STR]   = 0x1000000,
 789         [EBML_UTF8]  = 0x1000000,
 790         // max. 256 MB for binary data
 791         [EBML_BIN]   = 0x10000000,
 792         // no limits for anything else
 793     };
 794     ByteIOContext *pb = matroska->ctx->pb;
 795     uint32_t id = syntax->id;
 796     uint64_t length;
 797     int res;
 798
 799     data = (char *)data + syntax->data_offset;
 800     if (syntax->list_elem_size) {
 801         EbmlList *list = data;
 802         list->elem = av_realloc(list->elem, (list->nb_elem+1)*syntax->list_elem_size);
 803         data = (char*)list->elem + list->nb_elem*syntax->list_elem_size;
 804         memset(data, 0, syntax->list_elem_size);
 805         list->nb_elem++;
 806     }
 807
 808     if (syntax->type != EBML_PASS && syntax->type != EBML_STOP) {
 809         matroska->current_id = 0;
 810         if ((res = ebml_read_length(matroska, pb, &length)) < 0)
 811             return res;
 812         if (max_lengths[syntax->type] && length > max_lengths[syntax->type]) {
 813             av_log(matroska->ctx, AV_LOG_ERROR,
 814                    "Invalid length 0x%"PRIx64" > 0x%"PRIx64" for syntax element %i\n",
 815                    length, max_lengths[syntax->type], syntax->type);
 816             return AVERROR_INVALIDDATA;
 817         }
 818     }
 819
 820     switch (syntax->type) {
 821     case EBML_UINT:  res = ebml_read_uint  (pb, length, data);  break;
 822     case EBML_FLOAT: res = ebml_read_float (pb, length, data);  break;
 823     case EBML_STR:
 824     case EBML_UTF8:  res = ebml_read_ascii (pb, length, data);  break;
 825     case EBML_BIN:   res = ebml_read_binary(pb, length, data);  break;
 826     case EBML_NEST:  if ((res=ebml_read_master(matroska, length)) < 0)
 827                          return res;
 828                      if (id == MATROSKA_ID_SEGMENT)
 829                          matroska->segment_start = url_ftell(matroska->ctx->pb);
 830                      return ebml_parse_nest(matroska, syntax->def.n, data);
 831     case EBML_PASS:  return ebml_parse_id(matroska, syntax->def.n, id, data);
 832     case EBML_STOP:  return 1;
 833     default:         return url_fseek(pb,length,SEEK_CUR)<0 ? AVERROR(EIO) : 0;
 834     }
 835     if (res == AVERROR_INVALIDDATA)
 836         av_log(matroska->ctx, AV_LOG_ERROR, "Invalid element\n");
 837     else if (res == AVERROR(EIO))
 838         av_log(matroska->ctx, AV_LOG_ERROR, "Read error\n");
 839     return res;
 840 }
 841
 842 static void ebml_free(EbmlSyntax *syntax, void *data)
 843 {
 844     int i, j;
 845     for (i=0; syntax[i].id; i++) {
 846         void *data_off = (char *)data + syntax[i].data_offset;
 847         switch (syntax[i].type) {
 848         case EBML_STR:
 849         case EBML_UTF8:  av_freep(data_off);                      break;
 850         case EBML_BIN:   av_freep(&((EbmlBin *)data_off)->data);  break;
 851         case EBML_NEST:
 852             if (syntax[i].list_elem_size) {
 853                 EbmlList *list = data_off;
 854                 char *ptr = list->elem;
 855                 for (j=0; j<list->nb_elem; j++, ptr+=syntax[i].list_elem_size)
 856                     ebml_free(syntax[i].def.n, ptr);
 857                 av_free(list->elem);
 858             } else
 859                 ebml_free(syntax[i].def.n, data_off);
 860         default:  break;
 861         }
 862     }
 863 }
 864
 865
 866 /*
 867  * Autodetecting...
 868  */
 869 static int matroska_probe(AVProbeData *p)
 870 {
 871     uint64_t total = 0;
 872     int len_mask = 0x80, size = 1, n = 1, i;
 873
 874     /* EBML header? */
 875     if (AV_RB32(p->buf) != EBML_ID_HEADER)
 876         return 0;
 877
 878     /* length of header */
 879     total = p->buf[4];
 880     while (size <= 8 && !(total & len_mask)) {
 881         size++;
 882         len_mask >>= 1;
 883     }
 884     if (size > 8)
 885       return 0;
 886     total &= (len_mask - 1);
 887     while (n < size)
 888         total = (total << 8) | p->buf[4 + n++];
 889
 890     /* Does the probe data contain the whole header? */
 891     if (p->buf_size < 4 + size + total)
 892       return 0;
 893
 894     /* The header should contain a known document type. For now,
 895      * we don't parse the whole header but simply check for the
 896      * availability of that array of characters inside the header.
 897      * Not fully fool-proof, but good enough. */
 898     for (i = 0; i < FF_ARRAY_ELEMS(matroska_doctypes); i++) {
 899         int probelen = strlen(matroska_doctypes[i]);
 900         for (n = 4+size; n <= 4+size+total-probelen; n++)
 901             if (!memcmp(p->buf+n, matroska_doctypes[i], probelen))
 902                 return AVPROBE_SCORE_MAX;
 903     }
 904
 905     // probably valid EBML header but no recognized doctype
 906     return AVPROBE_SCORE_MAX/2;
 907 }
 908
 909 static MatroskaTrack *matroska_find_track_by_num(MatroskaDemuxContext *matroska,
 910                                                  int num)
 911 {
 912     MatroskaTrack *tracks = matroska->tracks.elem;
 913     int i;
 914
 915     for (i=0; i < matroska->tracks.nb_elem; i++)
 916         if (tracks[i].num == num)
 917             return &tracks[i];
 918
 919     av_log(matroska->ctx, AV_LOG_ERROR, "Invalid track number %d\n", num);
 920     return NULL;
 921 }
 922
 923 static int matroska_decode_buffer(uint8_t** buf, int* buf_size,
 924                                   MatroskaTrack *track)
 925 {
 926     MatroskaTrackEncoding *encodings = track->encodings.elem;
 927     uint8_t* data = *buf;
 928     int isize = *buf_size;
 929     uint8_t* pkt_data = NULL;
 930     int pkt_size = isize;
 931     int result = 0;
 932     int olen;
 933
 934     if (pkt_size >= 10000000)
 935         return -1;
 936
 937     switch (encodings[0].compression.algo) {
 938     case MATROSKA_TRACK_ENCODING_COMP_HEADERSTRIP:
 939         return encodings[0].compression.settings.size;
 940     case MATROSKA_TRACK_ENCODING_COMP_LZO:
 941         do {
 942             olen = pkt_size *= 3;
 943             pkt_data = av_realloc(pkt_data, pkt_size+AV_LZO_OUTPUT_PADDING);
 944             result = av_lzo1x_decode(pkt_data, &olen, data, &isize);
 945         } while (result==AV_LZO_OUTPUT_FULL && pkt_size<10000000);
 946         if (result)
 947             goto failed;
 948         pkt_size -= olen;
 949         break;
 950 #if CONFIG_ZLIB
 951     case MATROSKA_TRACK_ENCODING_COMP_ZLIB: {
 952         z_stream zstream = {0};
 953         if (inflateInit(&zstream) != Z_OK)
 954             return -1;
 955         zstream.next_in = data;
 956         zstream.avail_in = isize;
 957         do {
 958             pkt_size *= 3;
 959             pkt_data = av_realloc(pkt_data, pkt_size);
 960             zstream.avail_out = pkt_size - zstream.total_out;
 961             zstream.next_out = pkt_data + zstream.total_out;
 962             result = inflate(&zstream, Z_NO_FLUSH);
 963         } while (result==Z_OK && pkt_size<10000000);
 964         pkt_size = zstream.total_out;
 965         inflateEnd(&zstream);
 966         if (result != Z_STREAM_END)
 967             goto failed;
 968         break;
 969     }
 970 #endif
 971 #if CONFIG_BZLIB
 972     case MATROSKA_TRACK_ENCODING_COMP_BZLIB: {
 973         bz_stream bzstream = {0};
 974         if (BZ2_bzDecompressInit(&bzstream, 0, 0) != BZ_OK)
 975             return -1;
 976         bzstream.next_in = data;
 977         bzstream.avail_in = isize;
 978         do {
 979             pkt_size *= 3;
 980             pkt_data = av_realloc(pkt_data, pkt_size);
 981             bzstream.avail_out = pkt_size - bzstream.total_out_lo32;
 982             bzstream.next_out = pkt_data + bzstream.total_out_lo32;
 983             result = BZ2_bzDecompress(&bzstream);
 984         } while (result==BZ_OK && pkt_size<10000000);
 985         pkt_size = bzstream.total_out_lo32;
 986         BZ2_bzDecompressEnd(&bzstream);
 987         if (result != BZ_STREAM_END)
 988             goto failed;
 989         break;
 990     }
 991 #endif
 992     default:
 993         return -1;
 994     }
 995
 996     *buf = pkt_data;
 997     *buf_size = pkt_size;
 998     return 0;
 999  failed:
1000     av_free(pkt_data);
1001     return -1;
1002 }
1003
1004 static void matroska_fix_ass_packet(MatroskaDemuxContext *matroska,
1005                                     AVPacket *pkt, uint64_t display_duration)
1006 {
1007     char *line, *layer, *ptr = pkt->data, *end = ptr+pkt->size;
1008     for (; *ptr!=',' && ptr<end-1; ptr++);
1009     if (*ptr == ',')
1010         layer = ++ptr;
1011     for (; *ptr!=',' && ptr<end-1; ptr++);
1012     if (*ptr == ',') {
1013         int64_t end_pts = pkt->pts + display_duration;
1014         int sc = matroska->time_scale * pkt->pts / 10000000;
1015         int ec = matroska->time_scale * end_pts  / 10000000;
1016         int sh, sm, ss, eh, em, es, len;
1017         sh = sc/360000;  sc -= 360000*sh;
1018         sm = sc/  6000;  sc -=   6000*sm;
1019         ss = sc/   100;  sc -=    100*ss;
1020         eh = ec/360000;  ec -= 360000*eh;
1021         em = ec/  6000;  ec -=   6000*em;
1022         es = ec/   100;  ec -=    100*es;
1023         *ptr++ = '\0';
1024         len = 50 + end-ptr + FF_INPUT_BUFFER_PADDING_SIZE;
1025         if (!(line = av_malloc(len)))
1026             return;
1027         snprintf(line,len,"Dialogue: %s,%d:%02d:%02d.%02d,%d:%02d:%02d.%02d,%s\r\n",
1028                  layer, sh, sm, ss, sc, eh, em, es, ec, ptr);
1029         av_free(pkt->data);
1030         pkt->data = line;
1031         pkt->size = strlen(line);
1032     }
1033 }
1034
1035 static void matroska_merge_packets(AVPacket *out, AVPacket *in)
1036 {
1037     out->data = av_realloc(out->data, out->size+in->size);
1038     memcpy(out->data+out->size, in->data, in->size);
1039     out->size += in->size;
1040     av_destruct_packet(in);
1041     av_free(in);
1042 }
1043
1044 static void matroska_convert_tag(AVFormatContext *s, EbmlList *list,
1045                                  AVMetadata **metadata, char *prefix)
1046 {
1047     MatroskaTag *tags = list->elem;
1048     char key[1024];
1049     int i;
1050
1051     for (i=0; i < list->nb_elem; i++) {
1052         const char *lang = strcmp(tags[i].lang, "und") ? tags[i].lang : NULL;
1053
1054         if (!tags[i].name) {
1055             av_log(s, AV_LOG_WARNING, "Skipping invalid tag with no TagName.\n");
1056             continue;
1057         }
1058         if (prefix)  snprintf(key, sizeof(key), "%s/%s", prefix, tags[i].name);
1059         else         av_strlcpy(key, tags[i].name, sizeof(key));
1060         if (tags[i].def || !lang) {
1061         av_metadata_set2(metadata, key, tags[i].string, 0);
1062         if (tags[i].sub.nb_elem)
1063             matroska_convert_tag(s, &tags[i].sub, metadata, key);
1064         }
1065         if (lang) {
1066             av_strlcat(key, "-", sizeof(key));
1067             av_strlcat(key, lang, sizeof(key));
1068             av_metadata_set2(metadata, key, tags[i].string, 0);
1069             if (tags[i].sub.nb_elem)
1070                 matroska_convert_tag(s, &tags[i].sub, metadata, key);
1071         }
1072     }
1073     ff_metadata_conv(metadata, NULL, ff_mkv_metadata_conv);
1074 }
1075
1076 static void matroska_convert_tags(AVFormatContext *s)
1077 {
1078     MatroskaDemuxContext *matroska = s->priv_data;
1079     MatroskaTags *tags = matroska->tags.elem;
1080     int i, j;
1081
1082     for (i=0; i < matroska->tags.nb_elem; i++) {
1083         if (tags[i].target.attachuid) {
1084             MatroskaAttachement *attachment = matroska->attachments.elem;
1085             for (j=0; j<matroska->attachments.nb_elem; j++)
1086                 if (attachment[j].uid == tags[i].target.attachuid)
1087                     matroska_convert_tag(s, &tags[i].tag,
1088                                          &attachment[j].stream->metadata, NULL);
1089         } else if (tags[i].target.chapteruid) {
1090             MatroskaChapter *chapter = matroska->chapters.elem;
1091             for (j=0; j<matroska->chapters.nb_elem; j++)
1092                 if (chapter[j].uid == tags[i].target.chapteruid)
1093                     matroska_convert_tag(s, &tags[i].tag,
1094                                          &chapter[j].chapter->metadata, NULL);
1095         } else if (tags[i].target.trackuid) {
1096             MatroskaTrack *track = matroska->tracks.elem;
1097             for (j=0; j<matroska->tracks.nb_elem; j++)
1098                 if (track[j].uid == tags[i].target.trackuid)
1099                     matroska_convert_tag(s, &tags[i].tag,
1100                                          &track[j].stream->metadata, NULL);
1101         } else {
1102             matroska_convert_tag(s, &tags[i].tag, &s->metadata,
1103                                  tags[i].target.type);
1104         }
1105     }
1106 }
1107
1108 static void matroska_execute_seekhead(MatroskaDemuxContext *matroska)
1109 {
1110     EbmlList *seekhead_list = &matroska->seekhead;
1111     MatroskaSeekhead *seekhead = seekhead_list->elem;
1112     uint32_t level_up = matroska->level_up;
1113     int64_t before_pos = url_ftell(matroska->ctx->pb);
1114     uint32_t saved_id = matroska->current_id;
1115     MatroskaLevel level;
1116     int i;
1117
1118     // we should not do any seeking in the streaming case
1119     if (url_is_streamed(matroska->ctx->pb) ||
1120         (matroska->ctx->flags & AVFMT_FLAG_IGNIDX))
1121         return;
1122
1123     for (i=0; i<seekhead_list->nb_elem; i++) {
1124         int64_t offset = seekhead[i].pos + matroska->segment_start;
1125
1126         if (seekhead[i].pos <= before_pos
1127             || seekhead[i].id == MATROSKA_ID_SEEKHEAD
1128             || seekhead[i].id == MATROSKA_ID_CLUSTER)
1129             continue;
1130
1131         /* seek */
1132         if (url_fseek(matroska->ctx->pb, offset, SEEK_SET) != offset)
1133             continue;
1134
1135         /* We don't want to lose our seekhead level, so we add
1136          * a dummy. This is a crude hack. */
1137         if (matroska->num_levels == EBML_MAX_DEPTH) {
1138             av_log(matroska->ctx, AV_LOG_INFO,
1139                    "Max EBML element depth (%d) reached, "
1140                    "cannot parse further.\n", EBML_MAX_DEPTH);
1141             break;
1142         }
1143
1144         level.start = 0;
1145         level.length = (uint64_t)-1;
1146         matroska->levels[matroska->num_levels] = level;
1147         matroska->num_levels++;
1148         matroska->current_id = 0;
1149
1150         ebml_parse(matroska, matroska_segment, matroska);
1151
1152         /* remove dummy level */
1153         while (matroska->num_levels) {
1154             uint64_t length = matroska->levels[--matroska->num_levels].length;
1155             if (length == (uint64_t)-1)
1156                 break;
1157         }
1158     }
1159
1160     /* seek back */
1161     url_fseek(matroska->ctx->pb, before_pos, SEEK_SET);
1162     matroska->level_up = level_up;
1163     matroska->current_id = saved_id;
1164 }
1165
1166 static int matroska_aac_profile(char *codec_id)
1167 {
1168     static const char * const aac_profiles[] = { "MAIN", "LC", "SSR" };
1169     int profile;
1170
1171     for (profile=0; profile<FF_ARRAY_ELEMS(aac_profiles); profile++)
1172         if (strstr(codec_id, aac_profiles[profile]))
1173             break;
1174     return profile + 1;
1175 }
1176
1177 static int matroska_aac_sri(int samplerate)
1178 {
1179     int sri;
1180
1181     for (sri=0; sri<FF_ARRAY_ELEMS(ff_mpeg4audio_sample_rates); sri++)
1182         if (ff_mpeg4audio_sample_rates[sri] == samplerate)
1183             break;
1184     return sri;
1185 }
1186
1187 static int matroska_read_header(AVFormatContext *s, AVFormatParameters *ap)
1188 {
1189     MatroskaDemuxContext *matroska = s->priv_data;
1190     EbmlList *attachements_list = &matroska->attachments;
1191     MatroskaAttachement *attachements;
1192     EbmlList *chapters_list = &matroska->chapters;
1193     MatroskaChapter *chapters;
1194     MatroskaTrack *tracks;
1195     EbmlList *index_list;
1196     MatroskaIndex *index;
1197     int index_scale = 1;
1198     uint64_t max_start = 0;
1199     Ebml ebml = { 0 };
1200     AVStream *st;
1201     int i, j, res;
1202
1203     matroska->ctx = s;
1204
1205     /* First read the EBML header. */
1206     if (ebml_parse(matroska, ebml_syntax, &ebml)
1207         || ebml.version > EBML_VERSION       || ebml.max_size > sizeof(uint64_t)
1208         || ebml.id_length > sizeof(uint32_t) || ebml.doctype_version > 2) {
1209         av_log(matroska->ctx, AV_LOG_ERROR,
1210                "EBML header using unsupported features\n"
1211                "(EBML version %"PRIu64", doctype %s, doc version %"PRIu64")\n",
1212                ebml.version, ebml.doctype, ebml.doctype_version);
1213         ebml_free(ebml_syntax, &ebml);
1214         return AVERROR_PATCHWELCOME;
1215     }
1216     for (i = 0; i < FF_ARRAY_ELEMS(matroska_doctypes); i++)
1217         if (!strcmp(ebml.doctype, matroska_doctypes[i]))
1218             break;
1219     if (i >= FF_ARRAY_ELEMS(matroska_doctypes)) {
1220         av_log(s, AV_LOG_WARNING, "Unknown EBML doctype '%s'\n", ebml.doctype);
1221     }
1222     ebml_free(ebml_syntax, &ebml);
1223
1224     /* The next thing is a segment. */
1225     if ((res = ebml_parse(matroska, matroska_segments, matroska)) < 0)
1226         return res;
1227     matroska_execute_seekhead(matroska);
1228
1229     if (!matroska->time_scale)
1230         matroska->time_scale = 1000000;
1231     if (matroska->duration)
1232         matroska->ctx->duration = matroska->duration * matroska->time_scale
1233                                   * 1000 / AV_TIME_BASE;
1234     av_metadata_set2(&s->metadata, "title", matroska->title, 0);
1235
1236     tracks = matroska->tracks.elem;
1237     for (i=0; i < matroska->tracks.nb_elem; i++) {
1238         MatroskaTrack *track = &tracks[i];
1239         enum CodecID codec_id = CODEC_ID_NONE;
1240         EbmlList *encodings_list = &tracks->encodings;
1241         MatroskaTrackEncoding *encodings = encodings_list->elem;
1242         uint8_t *extradata = NULL;
1243         int extradata_size = 0;
1244         int extradata_offset = 0;
1245         ByteIOContext b;
1246
1247         /* Apply some sanity checks. */
1248         if (track->type != MATROSKA_TRACK_TYPE_VIDEO &&
1249             track->type != MATROSKA_TRACK_TYPE_AUDIO &&
1250             track->type != MATROSKA_TRACK_TYPE_SUBTITLE) {
1251             av_log(matroska->ctx, AV_LOG_INFO,
1252                    "Unknown or unsupported track type %"PRIu64"\n",
1253                    track->type);
1254             continue;
1255         }
1256         if (track->codec_id == NULL)
1257             continue;
1258
1259         if (track->type == MATROSKA_TRACK_TYPE_VIDEO) {
1260             if (!track->default_duration)
1261                 track->default_duration = 1000000000/track->video.frame_rate;
1262             if (!track->video.display_width)
1263                 track->video.display_width = track->video.pixel_width;
1264             if (!track->video.display_height)
1265                 track->video.display_height = track->video.pixel_height;
1266         } else if (track->type == MATROSKA_TRACK_TYPE_AUDIO) {
1267             if (!track->audio.out_samplerate)
1268                 track->audio.out_samplerate = track->audio.samplerate;
1269         }
1270         if (encodings_list->nb_elem > 1) {
1271             av_log(matroska->ctx, AV_LOG_ERROR,
1272                    "Multiple combined encodings no supported");
1273         } else if (encodings_list->nb_elem == 1) {
1274             if (encodings[0].type ||
1275                 (encodings[0].compression.algo != MATROSKA_TRACK_ENCODING_COMP_HEADERSTRIP &&
1276 #if CONFIG_ZLIB
1277                  encodings[0].compression.algo != MATROSKA_TRACK_ENCODING_COMP_ZLIB &&
1278 #endif
1279 #if CONFIG_BZLIB
1280                  encodings[0].compression.algo != MATROSKA_TRACK_ENCODING_COMP_BZLIB &&
1281 #endif
1282                  encodings[0].compression.algo != MATROSKA_TRACK_ENCODING_COMP_LZO)) {
1283                 encodings[0].scope = 0;
1284                 av_log(matroska->ctx, AV_LOG_ERROR,
1285                        "Unsupported encoding type");
1286             } else if (track->codec_priv.size && encodings[0].scope&2) {
1287                 uint8_t *codec_priv = track->codec_priv.data;
1288                 int offset = matroska_decode_buffer(&track->codec_priv.data,
1289                                                     &track->codec_priv.size,
1290                                                     track);
1291                 if (offset < 0) {
1292                     track->codec_priv.data = NULL;
1293                     track->codec_priv.size = 0;
1294                     av_log(matroska->ctx, AV_LOG_ERROR,
1295                            "Failed to decode codec private data\n");
1296                 } else if (offset > 0) {
1297                     track->codec_priv.data = av_malloc(track->codec_priv.size + offset);
1298                     memcpy(track->codec_priv.data,
1299                            encodings[0].compression.settings.data, offset);
1300                     memcpy(track->codec_priv.data+offset, codec_priv,
1301                            track->codec_priv.size);
1302                     track->codec_priv.size += offset;
1303                 }
1304                 if (codec_priv != track->codec_priv.data)
1305                     av_free(codec_priv);
1306             }
1307         }
1308
1309         for(j=0; ff_mkv_codec_tags[j].id != CODEC_ID_NONE; j++){
1310             if(!strncmp(ff_mkv_codec_tags[j].str, track->codec_id,
1311                         strlen(ff_mkv_codec_tags[j].str))){
1312                 codec_id= ff_mkv_codec_tags[j].id;
1313                 break;
1314             }
1315         }
1316
1317         st = track->stream = av_new_stream(s, 0);
1318         if (st == NULL)
1319             return AVERROR(ENOMEM);
1320
1321         if (!strcmp(track->codec_id, "V_MS/VFW/FOURCC")
1322             && track->codec_priv.size >= 40
1323             && track->codec_priv.data != NULL) {
1324             track->ms_compat = 1;
1325             track->video.fourcc = AV_RL32(track->codec_priv.data + 16);
1326             codec_id = ff_codec_get_id(ff_codec_bmp_tags, track->video.fourcc);
1327             extradata_offset = 40;
1328         } else if (!strcmp(track->codec_id, "A_MS/ACM")
1329                    && track->codec_priv.size >= 14
1330                    && track->codec_priv.data != NULL) {
1331             init_put_byte(&b, track->codec_priv.data, track->codec_priv.size,
1332                           URL_RDONLY, NULL, NULL, NULL, NULL);
1333             ff_get_wav_header(&b, st->codec, track->codec_priv.size);
1334             codec_id = st->codec->codec_id;
1335             extradata_offset = FFMIN(track->codec_priv.size, 18);
1336         } else if (!strcmp(track->codec_id, "V_QUICKTIME")
1337                    && (track->codec_priv.size >= 86)
1338                    && (track->codec_priv.data != NULL)) {
1339             track->video.fourcc = AV_RL32(track->codec_priv.data);
1340             codec_id=ff_codec_get_id(codec_movvideo_tags, track->video.fourcc);
1341         } else if (codec_id == CODEC_ID_PCM_S16BE) {
1342             switch (track->audio.bitdepth) {
1343             case  8:  codec_id = CODEC_ID_PCM_U8;     break;
1344             case 24:  codec_id = CODEC_ID_PCM_S24BE;  break;
1345             case 32:  codec_id = CODEC_ID_PCM_S32BE;  break;
1346             }
1347         } else if (codec_id == CODEC_ID_PCM_S16LE) {
1348             switch (track->audio.bitdepth) {
1349             case  8:  codec_id = CODEC_ID_PCM_U8;     break;
1350             case 24:  codec_id = CODEC_ID_PCM_S24LE;  break;
1351             case 32:  codec_id = CODEC_ID_PCM_S32LE;  break;
1352             }
1353         } else if (codec_id==CODEC_ID_PCM_F32LE && track->audio.bitdepth==64) {
1354             codec_id = CODEC_ID_PCM_F64LE;
1355         } else if (codec_id == CODEC_ID_AAC && !track->codec_priv.size) {
1356             int profile = matroska_aac_profile(track->codec_id);
1357             int sri = matroska_aac_sri(track->audio.samplerate);
1358             extradata = av_malloc(5);
1359             if (extradata == NULL)
1360                 return AVERROR(ENOMEM);
1361             extradata[0] = (profile << 3) | ((sri&0x0E) >> 1);
1362             extradata[1] = ((sri&0x01) << 7) | (track->audio.channels<<3);
1363             if (strstr(track->codec_id, "SBR")) {
1364                 sri = matroska_aac_sri(track->audio.out_samplerate);
1365                 extradata[2] = 0x56;
1366                 extradata[3] = 0xE5;
1367                 extradata[4] = 0x80 | (sri<<3);
1368                 extradata_size = 5;
1369             } else
1370                 extradata_size = 2;
1371         } else if (codec_id == CODEC_ID_TTA) {
1372             extradata_size = 30;
1373             extradata = av_mallocz(extradata_size);
1374             if (extradata == NULL)
1375                 return AVERROR(ENOMEM);
1376             init_put_byte(&b, extradata, extradata_size, 1,
1377                           NULL, NULL, NULL, NULL);
1378             put_buffer(&b, "TTA1", 4);
1379             put_le16(&b, 1);
1380             put_le16(&b, track->audio.channels);
1381             put_le16(&b, track->audio.bitdepth);
1382             put_le32(&b, track->audio.out_samplerate);
1383             put_le32(&b, matroska->ctx->duration * track->audio.out_samplerate);
1384         } else if (codec_id == CODEC_ID_RV10 || codec_id == CODEC_ID_RV20 ||
1385                    codec_id == CODEC_ID_RV30 || codec_id == CODEC_ID_RV40) {
1386             extradata_offset = 26;
1387         } else if (codec_id == CODEC_ID_RA_144) {
1388             track->audio.out_samplerate = 8000;
1389             track->audio.channels = 1;
1390         } else if (codec_id == CODEC_ID_RA_288 || codec_id == CODEC_ID_COOK ||
1391                    codec_id == CODEC_ID_ATRAC3 || codec_id == CODEC_ID_SIPR) {
1392             int flavor;
1393             init_put_byte(&b, track->codec_priv.data,track->codec_priv.size,
1394                           0, NULL, NULL, NULL, NULL);
1395             url_fskip(&b, 22);
1396             flavor                       = get_be16(&b);
1397             track->audio.coded_framesize = get_be32(&b);
1398             url_fskip(&b, 12);
1399             track->audio.sub_packet_h    = get_be16(&b);
1400             track->audio.frame_size      = get_be16(&b);
1401             track->audio.sub_packet_size = get_be16(&b);
1402             track->audio.buf = av_malloc(track->audio.frame_size * track->audio.sub_packet_h);
1403             if (codec_id == CODEC_ID_RA_288) {
1404                 st->codec->block_align = track->audio.coded_framesize;
1405                 track->codec_priv.size = 0;
1406             } else {
1407                 if (codec_id == CODEC_ID_SIPR && flavor < 4) {
1408                     const int sipr_bit_rate[4] = { 6504, 8496, 5000, 16000 };
1409                     track->audio.sub_packet_size = ff_sipr_subpk_size[flavor];
1410                     st->codec->bit_rate = sipr_bit_rate[flavor];
1411                 }
1412                 st->codec->block_align = track->audio.sub_packet_size;
1413                 extradata_offset = 78;
1414             }
1415         }
1416         track->codec_priv.size -= extradata_offset;
1417
1418         if (codec_id == CODEC_ID_NONE)
1419             av_log(matroska->ctx, AV_LOG_INFO,
1420                    "Unknown/unsupported CodecID %s.\n", track->codec_id);
1421
1422         if (track->time_scale < 0.01)
1423             track->time_scale = 1.0;
1424         av_set_pts_info(st, 64, matroska->time_scale*track->time_scale, 1000*1000*1000); /* 64 bit pts in ns */
1425
1426         st->codec->codec_id = codec_id;
1427         st->start_time = 0;
1428         if (strcmp(track->language, "und"))
1429             av_metadata_set2(&st->metadata, "language", track->language, 0);
1430         av_metadata_set2(&st->metadata, "title", track->name, 0);
1431
1432         if (track->flag_default)
1433             st->disposition |= AV_DISPOSITION_DEFAULT;
1434         if (track->flag_forced)
1435             st->disposition |= AV_DISPOSITION_FORCED;
1436
1437         if (track->default_duration)
1438             av_reduce(&st->codec->time_base.num, &st->codec->time_base.den,
1439                       track->default_duration, 1000000000, 30000);
1440
1441         if (!st->codec->extradata) {
1442             if(extradata){
1443                 st->codec->extradata = extradata;
1444                 st->codec->extradata_size = extradata_size;
1445             } else if(track->codec_priv.data && track->codec_priv.size > 0){
1446                 st->codec->extradata = av_mallocz(track->codec_priv.size +
1447                                                   FF_INPUT_BUFFER_PADDING_SIZE);
1448                 if(st->codec->extradata == NULL)
1449                     return AVERROR(ENOMEM);
1450                 st->codec->extradata_size = track->codec_priv.size;
1451                 memcpy(st->codec->extradata,
1452                        track->codec_priv.data + extradata_offset,
1453                        track->codec_priv.size);
1454             }
1455         }
1456
1457         if (track->type == MATROSKA_TRACK_TYPE_VIDEO) {
1458             st->codec->codec_type = AVMEDIA_TYPE_VIDEO;
1459             st->codec->codec_tag  = track->video.fourcc;
1460             st->codec->width  = track->video.pixel_width;
1461             st->codec->height = track->video.pixel_height;
1462             av_reduce(&st->sample_aspect_ratio.num,
1463                       &st->sample_aspect_ratio.den,
1464                       st->codec->height * track->video.display_width,
1465                       st->codec-> width * track->video.display_height,
1466                       255);
1467             if (st->codec->codec_id != CODEC_ID_H264)
1468             st->need_parsing = AVSTREAM_PARSE_HEADERS;
1469             if (track->default_duration)
1470                 st->avg_frame_rate = av_d2q(1000000000.0/track->default_duration, INT_MAX);
1471         } else if (track->type == MATROSKA_TRACK_TYPE_AUDIO) {
1472             st->codec->codec_type = AVMEDIA_TYPE_AUDIO;
1473             st->codec->sample_rate = track->audio.out_samplerate;
1474             st->codec->channels = track->audio.channels;
1475             if (st->codec->codec_id != CODEC_ID_AAC)
1476             st->need_parsing = AVSTREAM_PARSE_HEADERS;
1477         } else if (track->type == MATROSKA_TRACK_TYPE_SUBTITLE) {
1478             st->codec->codec_type = AVMEDIA_TYPE_SUBTITLE;
1479         }
1480     }
1481
1482     attachements = attachements_list->elem;
1483     for (j=0; j<attachements_list->nb_elem; j++) {
1484         if (!(attachements[j].filename && attachements[j].mime &&
1485               attachements[j].bin.data && attachements[j].bin.size > 0)) {
1486             av_log(matroska->ctx, AV_LOG_ERROR, "incomplete attachment\n");
1487         } else {
1488             AVStream *st = av_new_stream(s, 0);
1489             if (st == NULL)
1490                 break;
1491             av_metadata_set2(&st->metadata, "filename",attachements[j].filename, 0);
1492             st->codec->codec_id = CODEC_ID_NONE;
1493             st->codec->codec_type = AVMEDIA_TYPE_ATTACHMENT;
1494             st->codec->extradata  = av_malloc(attachements[j].bin.size);
1495             if(st->codec->extradata == NULL)
1496                 break;
1497             st->codec->extradata_size = attachements[j].bin.size;
1498             memcpy(st->codec->extradata, attachements[j].bin.data, attachements[j].bin.size);
1499
1500             for (i=0; ff_mkv_mime_tags[i].id != CODEC_ID_NONE; i++) {
1501                 if (!strncmp(ff_mkv_mime_tags[i].str, attachements[j].mime,
1502                              strlen(ff_mkv_mime_tags[i].str))) {
1503                     st->codec->codec_id = ff_mkv_mime_tags[i].id;
1504                     break;
1505                 }
1506             }
1507             attachements[j].stream = st;
1508         }
1509     }
1510
1511     chapters = chapters_list->elem;
1512     for (i=0; i<chapters_list->nb_elem; i++)
1513         if (chapters[i].start != AV_NOPTS_VALUE && chapters[i].uid
1514             && (max_start==0 || chapters[i].start > max_start)) {
1515             chapters[i].chapter =
1516             ff_new_chapter(s, chapters[i].uid, (AVRational){1, 1000000000},
1517                            chapters[i].start, chapters[i].end,
1518                            chapters[i].title);
1519             av_metadata_set2(&chapters[i].chapter->metadata,
1520                              "title", chapters[i].title, 0);
1521             max_start = chapters[i].start;
1522         }
1523
1524     index_list = &matroska->index;
1525     index = index_list->elem;
1526     if (index_list->nb_elem
1527         && index[0].time > 100000000000000/matroska->time_scale) {
1528         av_log(matroska->ctx, AV_LOG_WARNING, "Working around broken index.\n");
1529         index_scale = matroska->time_scale;
1530     }
1531     for (i=0; i<index_list->nb_elem; i++) {
1532         EbmlList *pos_list = &index[i].pos;
1533         MatroskaIndexPos *pos = pos_list->elem;
1534         for (j=0; j<pos_list->nb_elem; j++) {
1535             MatroskaTrack *track = matroska_find_track_by_num(matroska,
1536                                                               pos[j].track);
1537             if (track && track->stream)
1538                 av_add_index_entry(track->stream,
1539                                    pos[j].pos + matroska->segment_start,
1540                                    index[i].time/index_scale, 0, 0,
1541                                    AVINDEX_KEYFRAME);
1542         }
1543     }
1544
1545     matroska_convert_tags(s);
1546
1547     return 0;
1548 }
1549
1550 /*
1551  * Put one packet in an application-supplied AVPacket struct.
1552  * Returns 0 on success or -1 on failure.
1553  */
1554 static int matroska_deliver_packet(MatroskaDemuxContext *matroska,
1555                                    AVPacket *pkt)
1556 {
1557     if (matroska->num_packets > 0) {
1558         memcpy(pkt, matroska->packets[0], sizeof(AVPacket));
1559         av_free(matroska->packets[0]);
1560         if (matroska->num_packets > 1) {
1561             memmove(&matroska->packets[0], &matroska->packets[1],
1562                     (matroska->num_packets - 1) * sizeof(AVPacket *));
1563             matroska->packets =
1564                 av_realloc(matroska->packets, (matroska->num_packets - 1) *
1565                            sizeof(AVPacket *));
1566         } else {
1567             av_freep(&matroska->packets);
1568         }
1569         matroska->num_packets--;
1570         return 0;
1571     }
1572
1573     return -1;
1574 }
1575
1576 /*
1577  * Free all packets in our internal queue.
1578  */
1579 static void matroska_clear_queue(MatroskaDemuxContext *matroska)
1580 {
1581     if (matroska->packets) {
1582         int n;
1583         for (n = 0; n < matroska->num_packets; n++) {
1584             av_free_packet(matroska->packets[n]);
1585             av_free(matroska->packets[n]);
1586         }
1587         av_freep(&matroska->packets);
1588         matroska->num_packets = 0;
1589     }
1590 }
1591
1592 static int matroska_parse_block(MatroskaDemuxContext *matroska, uint8_t *data,
1593                                 int size, int64_t pos, uint64_t cluster_time,
1594                                 uint64_t duration, int is_keyframe,
1595                                 int64_t cluster_pos)
1596 {
1597     uint64_t timecode = AV_NOPTS_VALUE;
1598     MatroskaTrack *track;
1599     int res = 0;
1600     AVStream *st;
1601     AVPacket *pkt;
1602     int16_t block_time;
1603     uint32_t *lace_size = NULL;
1604     int n, flags, laces = 0;
1605     uint64_t num;
1606
1607     if ((n = matroska_ebmlnum_uint(matroska, data, size, &num)) < 0) {
1608         av_log(matroska->ctx, AV_LOG_ERROR, "EBML block data error\n");
1609         return res;
1610     }
1611     data += n;
1612     size -= n;
1613
1614     track = matroska_find_track_by_num(matroska, num);
1615     if (size <= 3 || !track || !track->stream) {
1616         av_log(matroska->ctx, AV_LOG_INFO,
1617                "Invalid stream %"PRIu64" or size %u\n", num, size);
1618         return res;
1619     }
1620     st = track->stream;
1621     if (st->discard >= AVDISCARD_ALL)
1622         return res;
1623     if (duration == AV_NOPTS_VALUE)
1624         duration = track->default_duration / matroska->time_scale;
1625
1626     block_time = AV_RB16(data);
1627     data += 2;
1628     flags = *data++;
1629     size -= 3;
1630     if (is_keyframe == -1)
1631         is_keyframe = flags & 0x80 ? AV_PKT_FLAG_KEY : 0;
1632
1633     if (cluster_time != (uint64_t)-1
1634         && (block_time >= 0 || cluster_time >= -block_time)) {
1635         timecode = cluster_time + block_time;
1636         if (track->type == MATROSKA_TRACK_TYPE_SUBTITLE
1637             && timecode < track->end_timecode)
1638             is_keyframe = 0;  /* overlapping subtitles are not key frame */
1639         if (is_keyframe)
1640             av_add_index_entry(st, cluster_pos, timecode, 0,0,AVINDEX_KEYFRAME);
1641         track->end_timecode = FFMAX(track->end_timecode, timecode+duration);
1642     }
1643
1644     if (matroska->skip_to_keyframe && track->type != MATROSKA_TRACK_TYPE_SUBTITLE) {
1645         if (!is_keyframe || timecode < matroska->skip_to_timecode)
1646             return res;
1647         matroska->skip_to_keyframe = 0;
1648     }
1649
1650     switch ((flags & 0x06) >> 1) {
1651         case 0x0: /* no lacing */
1652             laces = 1;
1653             lace_size = av_mallocz(sizeof(int));
1654             lace_size[0] = size;
1655             break;
1656
1657         case 0x1: /* Xiph lacing */
1658         case 0x2: /* fixed-size lacing */
1659         case 0x3: /* EBML lacing */
1660             assert(size>0); // size <=3 is checked before size-=3 above
1661             laces = (*data) + 1;
1662             data += 1;
1663             size -= 1;
1664             lace_size = av_mallocz(laces * sizeof(int));
1665
1666             switch ((flags & 0x06) >> 1) {
1667                 case 0x1: /* Xiph lacing */ {
1668                     uint8_t temp;
1669                     uint32_t total = 0;
1670                     for (n = 0; res == 0 && n < laces - 1; n++) {
1671                         while (1) {
1672                             if (size == 0) {
1673                                 res = -1;
1674                                 break;
1675                             }
1676                             temp = *data;
1677                             lace_size[n] += temp;
1678                             data += 1;
1679                             size -= 1;
1680                             if (temp != 0xff)
1681                                 break;
1682                         }
1683                         total += lace_size[n];
1684                     }
1685                     lace_size[n] = size - total;
1686                     break;
1687                 }
1688
1689                 case 0x2: /* fixed-size lacing */
1690                     for (n = 0; n < laces; n++)
1691                         lace_size[n] = size / laces;
1692                     break;
1693
1694                 case 0x3: /* EBML lacing */ {
1695                     uint32_t total;
1696                     n = matroska_ebmlnum_uint(matroska, data, size, &num);
1697                     if (n < 0) {
1698                         av_log(matroska->ctx, AV_LOG_INFO,
1699                                "EBML block data error\n");
1700                         break;
1701                     }
1702                     data += n;
1703                     size -= n;
1704                     total = lace_size[0] = num;
1705                     for (n = 1; res == 0 && n < laces - 1; n++) {
1706                         int64_t snum;
1707                         int r;
1708                         r = matroska_ebmlnum_sint(matroska, data, size, &snum);
1709                         if (r < 0) {
1710                             av_log(matroska->ctx, AV_LOG_INFO,
1711                                    "EBML block data error\n");
1712                             break;
1713                         }
1714                         data += r;
1715                         size -= r;
1716                         lace_size[n] = lace_size[n - 1] + snum;
1717                         total += lace_size[n];
1718                     }
1719                     lace_size[n] = size - total;
1720                     break;
1721                 }
1722             }
1723             break;
1724     }
1725
1726     if (res == 0) {
1727         for (n = 0; n < laces; n++) {
1728             if ((st->codec->codec_id == CODEC_ID_RA_288 ||
1729                  st->codec->codec_id == CODEC_ID_COOK ||
1730                  st->codec->codec_id == CODEC_ID_SIPR ||
1731                  st->codec->codec_id == CODEC_ID_ATRAC3) &&
1732                  st->codec->block_align && track->audio.sub_packet_size) {
1733                 int a = st->codec->block_align;
1734                 int sps = track->audio.sub_packet_size;
1735                 int cfs = track->audio.coded_framesize;
1736                 int h = track->audio.sub_packet_h;
1737                 int y = track->audio.sub_packet_cnt;
1738                 int w = track->audio.frame_size;
1739                 int x;
1740
1741                 if (!track->audio.pkt_cnt) {
1742                     if (st->codec->codec_id == CODEC_ID_RA_288)
1743                         for (x=0; x<h/2; x++)
1744                             memcpy(track->audio.buf+x*2*w+y*cfs,
1745                                    data+x*cfs, cfs);
1746                     else if (st->codec->codec_id == CODEC_ID_SIPR)
1747                         memcpy(track->audio.buf + y*w, data, w);
1748                     else
1749                         for (x=0; x<w/sps; x++)
1750                             memcpy(track->audio.buf+sps*(h*x+((h+1)/2)*(y&1)+(y>>1)), data+x*sps, sps);
1751
1752                     if (++track->audio.sub_packet_cnt >= h) {
1753                         if (st->codec->codec_id == CODEC_ID_SIPR)
1754                             ff_rm_reorder_sipr_data(track->audio.buf, h, w);
1755                         track->audio.sub_packet_cnt = 0;
1756                         track->audio.pkt_cnt = h*w / a;
1757                     }
1758                 }
1759                 while (track->audio.pkt_cnt) {
1760                     pkt = av_mallocz(sizeof(AVPacket));
1761                     av_new_packet(pkt, a);
1762                     memcpy(pkt->data, track->audio.buf
1763                            + a * (h*w / a - track->audio.pkt_cnt--), a);
1764                     pkt->pos = pos;
1765                     pkt->stream_index = st->index;
1766                     dynarray_add(&matroska->packets,&matroska->num_packets,pkt);
1767                 }
1768             } else {
1769                 MatroskaTrackEncoding *encodings = track->encodings.elem;
1770                 int offset = 0, pkt_size = lace_size[n];
1771                 uint8_t *pkt_data = data;
1772
1773                 if (pkt_size > size) {
1774                     av_log(matroska->ctx, AV_LOG_ERROR, "Invalid packet size\n");
1775                     break;
1776                 }
1777
1778                 if (encodings && encodings->scope & 1) {
1779                     offset = matroska_decode_buffer(&pkt_data,&pkt_size, track);
1780                     if (offset < 0)
1781                         continue;
1782                 }
1783
1784                 pkt = av_mallocz(sizeof(AVPacket));
1785                 /* XXX: prevent data copy... */
1786                 if (av_new_packet(pkt, pkt_size+offset) < 0) {
1787                     av_free(pkt);
1788                     res = AVERROR(ENOMEM);
1789                     break;
1790                 }
1791                 if (offset)
1792                     memcpy (pkt->data, encodings->compression.settings.data, offset);
1793                 memcpy (pkt->data+offset, pkt_data, pkt_size);
1794
1795                 if (pkt_data != data)
1796                     av_free(pkt_data);
1797
1798                 if (n == 0)
1799                     pkt->flags = is_keyframe;
1800                 pkt->stream_index = st->index;
1801
1802                 if (track->ms_compat)
1803                     pkt->dts = timecode;
1804                 else
1805                     pkt->pts = timecode;
1806                 pkt->pos = pos;
1807                 if (st->codec->codec_id == CODEC_ID_TEXT)
1808                     pkt->convergence_duration = duration;
1809                 else if (track->type != MATROSKA_TRACK_TYPE_SUBTITLE)
1810                     pkt->duration = duration;
1811
1812                 if (st->codec->codec_id == CODEC_ID_SSA)
1813                     matroska_fix_ass_packet(matroska, pkt, duration);
1814
1815                 if (matroska->prev_pkt &&
1816                     timecode != AV_NOPTS_VALUE &&
1817                     matroska->prev_pkt->pts == timecode &&
1818                     matroska->prev_pkt->stream_index == st->index &&
1819                     st->codec->codec_id == CODEC_ID_SSA)
1820                     matroska_merge_packets(matroska->prev_pkt, pkt);
1821                 else {
1822                     dynarray_add(&matroska->packets,&matroska->num_packets,pkt);
1823                     matroska->prev_pkt = pkt;
1824                 }
1825             }
1826
1827             if (timecode != AV_NOPTS_VALUE)
1828                 timecode = duration ? timecode + duration : AV_NOPTS_VALUE;
1829             data += lace_size[n];
1830             size -= lace_size[n];
1831         }
1832     }
1833
1834     av_free(lace_size);
1835     return res;
1836 }
1837
1838 static int matroska_parse_cluster(MatroskaDemuxContext *matroska)
1839 {
1840     MatroskaCluster cluster = { 0 };
1841     EbmlList *blocks_list;
1842     MatroskaBlock *blocks;
1843     int i, res;
1844     int64_t pos = url_ftell(matroska->ctx->pb);
1845     matroska->prev_pkt = NULL;
1846     if (matroska->current_id)
1847         pos -= 4;  /* sizeof the ID which was already read */
1848     res = ebml_parse(matroska, matroska_clusters, &cluster);
1849     blocks_list = &cluster.blocks;
1850     blocks = blocks_list->elem;
1851     for (i=0; i<blocks_list->nb_elem; i++)
1852         if (blocks[i].bin.size > 0 && blocks[i].bin.data) {
1853             int is_keyframe = blocks[i].non_simple ? !blocks[i].reference : -1;
1854             res=matroska_parse_block(matroska,
1855                                      blocks[i].bin.data, blocks[i].bin.size,
1856                                      blocks[i].bin.pos,  cluster.timecode,
1857                                      blocks[i].duration, is_keyframe,
1858                                      pos);
1859         }
1860     ebml_free(matroska_cluster, &cluster);
1861     if (res < 0)  matroska->done = 1;
1862     return res;
1863 }
1864
1865 static int matroska_read_packet(AVFormatContext *s, AVPacket *pkt)
1866 {
1867     MatroskaDemuxContext *matroska = s->priv_data;
1868
1869     while (matroska_deliver_packet(matroska, pkt)) {
1870         if (matroska->done)
1871             return AVERROR_EOF;
1872         matroska_parse_cluster(matroska);
1873     }
1874
1875     return 0;
1876 }
1877
1878 static int matroska_read_seek(AVFormatContext *s, int stream_index,
1879                               int64_t timestamp, int flags)
1880 {
1881     MatroskaDemuxContext *matroska = s->priv_data;
1882     MatroskaTrack *tracks = matroska->tracks.elem;
1883     AVStream *st = s->streams[stream_index];
1884     int i, index, index_sub, index_min;
1885
1886     if (!st->nb_index_entries)
1887         return 0;
1888     timestamp = FFMAX(timestamp, st->index_entries[0].timestamp);
1889
1890     if ((index = av_index_search_timestamp(st, timestamp, flags)) < 0) {
1891         url_fseek(s->pb, st->index_entries[st->nb_index_entries-1].pos, SEEK_SET);
1892         while ((index = av_index_search_timestamp(st, timestamp, flags)) < 0) {
1893             matroska_clear_queue(matroska);
1894             if (matroska_parse_cluster(matroska) < 0)
1895                 break;
1896         }
1897     }
1898
1899     matroska_clear_queue(matroska);
1900     if (index < 0)
1901         return 0;
1902
1903     index_min = index;
1904     for (i=0; i < matroska->tracks.nb_elem; i++) {
1905         tracks[i].end_timecode = 0;
1906         if (tracks[i].type == MATROSKA_TRACK_TYPE_SUBTITLE
1907             && !tracks[i].stream->discard != AVDISCARD_ALL) {
1908             index_sub = av_index_search_timestamp(tracks[i].stream, st->index_entries[index].timestamp, AVSEEK_FLAG_BACKWARD);
1909             if (index_sub >= 0
1910                 && st->index_entries[index_sub].pos < st->index_entries[index_min].pos
1911                 && st->index_entries[index].timestamp - st->index_entries[index_sub].timestamp < 30000000000/matroska->time_scale)
1912                 index_min = index_sub;
1913         }
1914     }
1915
1916     url_fseek(s->pb, st->index_entries[index_min].pos, SEEK_SET);
1917     matroska->skip_to_keyframe = !(flags & AVSEEK_FLAG_ANY);
1918     matroska->skip_to_timecode = st->index_entries[index].timestamp;
1919     matroska->done = 0;
1920     av_update_cur_dts(s, st, st->index_entries[index].timestamp);
1921     return 0;
1922 }
1923
1924 static int matroska_read_close(AVFormatContext *s)
1925 {
1926     MatroskaDemuxContext *matroska = s->priv_data;
1927     MatroskaTrack *tracks = matroska->tracks.elem;
1928     int n;
1929
1930     matroska_clear_queue(matroska);
1931
1932     for (n=0; n < matroska->tracks.nb_elem; n++)
1933         if (tracks[n].type == MATROSKA_TRACK_TYPE_AUDIO)
1934             av_free(tracks[n].audio.buf);
1935     ebml_free(matroska_segment, matroska);
1936
1937     return 0;
1938 }
1939
1940 AVInputFormat ff_matroska_demuxer = {
1941     "matroska,webm",
1942     NULL_IF_CONFIG_SMALL("Matroska/WebM file format"),
1943     sizeof(MatroskaDemuxContext),
1944     matroska_probe,
1945     matroska_read_header,
1946     matroska_read_packet,
1947     matroska_read_close,
1948     matroska_read_seek,
1949 };