ffmpeg/libavformat/matroskadec.c

2849 lines
90 KiB
C
Raw Normal View History

/*
* Matroska file demuxer (no muxer yet)
* Copyright (c) 2003-2004 The ffmpeg Project
*
* This file is part of FFmpeg.
*
* FFmpeg is free software; you can redistribute it and/or
* modify it under the terms of the GNU Lesser General Public
* License as published by the Free Software Foundation; either
* version 2.1 of the License, or (at your option) any later version.
*
* FFmpeg is distributed in the hope that it will be useful,
* but WITHOUT ANY WARRANTY; without even the implied warranty of
* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
* Lesser General Public License for more details.
*
* You should have received a copy of the GNU Lesser General Public
* License along with FFmpeg; if not, write to the Free Software
* Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA
*/
/**
* @file matroskadec.c
* Matroska file demuxer
* by Ronald Bultje <rbultje@ronald.bitfreak.net>
* with a little help from Moritz Bunkus <moritz@bunkus.org>
* Specs available on the matroska project page:
* http://www.matroska.org/.
*/
#include "avformat.h"
/* For codec_get_id(). */
#include "riff.h"
#include "intfloat_readwrite.h"
#include "matroska.h"
typedef struct Track {
MatroskaTrackType type;
/* Unique track number and track ID. stream_index is the index that
* the calling app uses for this track. */
uint32_t num;
uint32_t uid;
int stream_index;
char *name;
char language[4];
char *codec_id;
char *codec_name;
unsigned char *codec_priv;
int codec_priv_size;
uint64_t default_duration;
MatroskaTrackFlags flags;
} MatroskaTrack;
typedef struct MatroskaVideoTrack {
MatroskaTrack track;
int pixel_width;
int pixel_height;
int display_width;
int display_height;
uint32_t fourcc;
MatroskaAspectRatioMode ar_mode;
MatroskaEyeMode eye_mode;
//..
} MatroskaVideoTrack;
typedef struct MatroskaAudioTrack {
MatroskaTrack track;
int channels;
int bitdepth;
int internal_samplerate;
int samplerate;
int block_align;
/* real audio header */
int coded_framesize;
int sub_packet_h;
int frame_size;
int sub_packet_size;
int sub_packet_cnt;
int pkt_cnt;
uint8_t *buf;
//..
} MatroskaAudioTrack;
typedef struct MatroskaSubtitleTrack {
MatroskaTrack track;
//..
} MatroskaSubtitleTrack;
#define MAX_TRACK_SIZE (FFMAX(FFMAX(sizeof(MatroskaVideoTrack), \
sizeof(MatroskaAudioTrack)), \
sizeof(MatroskaSubtitleTrack)))
typedef struct MatroskaLevel {
uint64_t start;
uint64_t length;
} MatroskaLevel;
typedef struct MatroskaDemuxIndex {
uint64_t pos; /* of the corresponding *cluster*! */
uint16_t track; /* reference to 'num' */
uint64_t time; /* in nanoseconds */
} MatroskaDemuxIndex;
typedef struct MatroskaDemuxContext {
AVFormatContext *ctx;
/* ebml stuff */
int num_levels;
MatroskaLevel levels[EBML_MAX_DEPTH];
int level_up;
/* matroska stuff */
char *writing_app;
char *muxing_app;
int64_t created;
/* timescale in the file */
int64_t time_scale;
/* num_streams is the number of streams that av_new_stream() was called
* for ( = that are available to the calling program). */
int num_tracks;
int num_streams;
MatroskaTrack *tracks[MAX_STREAMS];
/* cache for ID peeking */
uint32_t peek_id;
/* byte position of the segment inside the stream */
offset_t segment_start;
/* The packet queue. */
AVPacket **packets;
int num_packets;
/* have we already parse metadata/cues/clusters? */
int metadata_parsed;
int index_parsed;
int done;
/* The index for seeking. */
int num_indexes;
MatroskaDemuxIndex *index;
/* What to skip before effectively reading a packet. */
int skip_to_keyframe;
AVStream *skip_to_stream;
} MatroskaDemuxContext;
/*
* The first few functions handle EBML file parsing. The rest
* is the document interpretation. Matroska really just is a
* EBML file.
*/
/*
* Return: the amount of levels in the hierarchy that the
* current element lies higher than the previous one.
* The opposite isn't done - that's auto-done using master
* element reading.
*/
static int
ebml_read_element_level_up (MatroskaDemuxContext *matroska)
{
ByteIOContext *pb = matroska->ctx->pb;
offset_t pos = url_ftell(pb);
int num = 0;
while (matroska->num_levels > 0) {
MatroskaLevel *level = &matroska->levels[matroska->num_levels - 1];
if (pos >= level->start + level->length) {
matroska->num_levels--;
num++;
} else {
break;
}
}
return num;
}
/*
* Read: an "EBML number", which is defined as a variable-length
* array of bytes. The first byte indicates the length by giving a
* number of 0-bits followed by a one. The position of the first
* "one" bit inside the first byte indicates the length of this
* number.
* Returns: num. of bytes read. < 0 on error.
*/
static int
ebml_read_num (MatroskaDemuxContext *matroska,
int max_size,
uint64_t *number)
{
ByteIOContext *pb = matroska->ctx->pb;
int len_mask = 0x80, read = 1, n = 1;
int64_t total = 0;
/* the first byte tells us the length in bytes - get_byte() can normally
* return 0, but since that's not a valid first ebmlID byte, we can
* use it safely here to catch EOS. */
if (!(total = get_byte(pb))) {
/* we might encounter EOS here */
if (!url_feof(pb)) {
offset_t pos = url_ftell(pb);
av_log(matroska->ctx, AV_LOG_ERROR,
"Read error at pos. %"PRIu64" (0x%"PRIx64")\n",
pos, pos);
}
return AVERROR(EIO); /* EOS or actual I/O error */
}
/* get the length of the EBML number */
while (read <= max_size && !(total & len_mask)) {
read++;
len_mask >>= 1;
}
if (read > max_size) {
offset_t pos = url_ftell(pb) - 1;
av_log(matroska->ctx, AV_LOG_ERROR,
"Invalid EBML number size tag 0x%02x at pos %"PRIu64" (0x%"PRIx64")\n",
(uint8_t) total, pos, pos);
return AVERROR_INVALIDDATA;
}
/* read out length */
total &= ~len_mask;
while (n++ < read)
total = (total << 8) | get_byte(pb);
*number = total;
return read;
}
/*
* Read: the element content data ID.
* Return: the number of bytes read or < 0 on error.
*/
static int
ebml_read_element_id (MatroskaDemuxContext *matroska,
uint32_t *id,
int *level_up)
{
int read;
uint64_t total;
/* if we re-call this, use our cached ID */
if (matroska->peek_id != 0) {
if (level_up)
*level_up = 0;
*id = matroska->peek_id;
return 0;
}
/* read out the "EBML number", include tag in ID */
if ((read = ebml_read_num(matroska, 4, &total)) < 0)
return read;
*id = matroska->peek_id = total | (1 << (read * 7));
/* level tracking */
if (level_up)
*level_up = ebml_read_element_level_up(matroska);
return read;
}
/*
* Read: element content length.
* Return: the number of bytes read or < 0 on error.
*/
static int
ebml_read_element_length (MatroskaDemuxContext *matroska,
uint64_t *length)
{
/* clear cache since we're now beyond that data point */
matroska->peek_id = 0;
/* read out the "EBML number", include tag in ID */
return ebml_read_num(matroska, 8, length);
}
/*
* Return: the ID of the next element, or 0 on error.
* Level_up contains the amount of levels that this
* next element lies higher than the previous one.
*/
static uint32_t
ebml_peek_id (MatroskaDemuxContext *matroska,
int *level_up)
{
uint32_t id;
if (ebml_read_element_id(matroska, &id, level_up) < 0)
return 0;
return id;
}
/*
* Seek to a given offset.
* 0 is success, -1 is failure.
*/
static int
ebml_read_seek (MatroskaDemuxContext *matroska,
offset_t offset)
{
ByteIOContext *pb = matroska->ctx->pb;
/* clear ID cache, if any */
matroska->peek_id = 0;
return (url_fseek(pb, offset, SEEK_SET) == offset) ? 0 : -1;
}
/*
* Skip the next element.
* 0 is success, -1 is failure.
*/
static int
ebml_read_skip (MatroskaDemuxContext *matroska)
{
ByteIOContext *pb = matroska->ctx->pb;
uint32_t id;
uint64_t length;
int res;
if ((res = ebml_read_element_id(matroska, &id, NULL)) < 0 ||
(res = ebml_read_element_length(matroska, &length)) < 0)
return res;
url_fskip(pb, length);
return 0;
}
/*
* Read the next element as an unsigned int.
* 0 is success, < 0 is failure.
*/
static int
ebml_read_uint (MatroskaDemuxContext *matroska,
uint32_t *id,
uint64_t *num)
{
ByteIOContext *pb = matroska->ctx->pb;
int n = 0, size, res;
uint64_t rlength;
if ((res = ebml_read_element_id(matroska, id, NULL)) < 0 ||
(res = ebml_read_element_length(matroska, &rlength)) < 0)
return res;
size = rlength;
if (size < 1 || size > 8) {
offset_t pos = url_ftell(pb);
av_log(matroska->ctx, AV_LOG_ERROR,
"Invalid uint element size %d at position %"PRId64" (0x%"PRIx64")\n",
size, pos, pos);
return AVERROR_INVALIDDATA;
}
/* big-endian ordening; build up number */
*num = 0;
while (n++ < size)
*num = (*num << 8) | get_byte(pb);
return 0;
}
/*
* Read the next element as a signed int.
* 0 is success, < 0 is failure.
*/
static int
ebml_read_sint (MatroskaDemuxContext *matroska,
uint32_t *id,
int64_t *num)
{
ByteIOContext *pb = matroska->ctx->pb;
int size, n = 1, negative = 0, res;
uint64_t rlength;
if ((res = ebml_read_element_id(matroska, id, NULL)) < 0 ||
(res = ebml_read_element_length(matroska, &rlength)) < 0)
return res;
size = rlength;
if (size < 1 || size > 8) {
offset_t pos = url_ftell(pb);
av_log(matroska->ctx, AV_LOG_ERROR,
"Invalid sint element size %d at position %"PRId64" (0x%"PRIx64")\n",
size, pos, pos);
return AVERROR_INVALIDDATA;
}
if ((*num = get_byte(pb)) & 0x80) {
negative = 1;
*num &= ~0x80;
}
while (n++ < size)
*num = (*num << 8) | get_byte(pb);
/* make signed */
if (negative)
*num = *num - (1LL << ((8 * size) - 1));
return 0;
}
/*
* Read the next element as a float.
* 0 is success, < 0 is failure.
*/
static int
ebml_read_float (MatroskaDemuxContext *matroska,
uint32_t *id,
double *num)
{
ByteIOContext *pb = matroska->ctx->pb;
int size, res;
uint64_t rlength;
if ((res = ebml_read_element_id(matroska, id, NULL)) < 0 ||
(res = ebml_read_element_length(matroska, &rlength)) < 0)
return res;
size = rlength;
if (size == 4) {
*num= av_int2flt(get_be32(pb));
} else if(size==8){
*num= av_int2dbl(get_be64(pb));
} else{
offset_t pos = url_ftell(pb);
av_log(matroska->ctx, AV_LOG_ERROR,
"Invalid float element size %d at position %"PRIu64" (0x%"PRIx64")\n",
size, pos, pos);
return AVERROR_INVALIDDATA;
}
return 0;
}
/*
* Read the next element as an ASCII string.
* 0 is success, < 0 is failure.
*/
static int
ebml_read_ascii (MatroskaDemuxContext *matroska,
uint32_t *id,
char **str)
{
ByteIOContext *pb = matroska->ctx->pb;
int size, res;
uint64_t rlength;
if ((res = ebml_read_element_id(matroska, id, NULL)) < 0 ||
(res = ebml_read_element_length(matroska, &rlength)) < 0)
return res;
size = rlength;
/* ebml strings are usually not 0-terminated, so we allocate one
* byte more, read the string and NULL-terminate it ourselves. */
if (size < 0 || !(*str = av_malloc(size + 1))) {
av_log(matroska->ctx, AV_LOG_ERROR, "Memory allocation failed\n");
return AVERROR(ENOMEM);
}
if (get_buffer(pb, (uint8_t *) *str, size) != size) {
offset_t pos = url_ftell(pb);
av_log(matroska->ctx, AV_LOG_ERROR,
"Read error at pos. %"PRIu64" (0x%"PRIx64")\n", pos, pos);
return AVERROR(EIO);
}
(*str)[size] = '\0';
return 0;
}
/*
* Read the next element as a UTF-8 string.
* 0 is success, < 0 is failure.
*/
static int
ebml_read_utf8 (MatroskaDemuxContext *matroska,
uint32_t *id,
char **str)
{
return ebml_read_ascii(matroska, id, str);
}
/*
* Read the next element as a date (nanoseconds since 1/1/2000).
* 0 is success, < 0 is failure.
*/
static int
ebml_read_date (MatroskaDemuxContext *matroska,
uint32_t *id,
int64_t *date)
{
return ebml_read_sint(matroska, id, date);
}
/*
* Read the next element, but only the header. The contents
* are supposed to be sub-elements which can be read separately.
* 0 is success, < 0 is failure.
*/
static int
ebml_read_master (MatroskaDemuxContext *matroska,
uint32_t *id)
{
ByteIOContext *pb = matroska->ctx->pb;
uint64_t length;
MatroskaLevel *level;
int res;
if ((res = ebml_read_element_id(matroska, id, NULL)) < 0 ||
(res = ebml_read_element_length(matroska, &length)) < 0)
return res;
/* protect... (Heaven forbids that the '>' is true) */
if (matroska->num_levels >= EBML_MAX_DEPTH) {
av_log(matroska->ctx, AV_LOG_ERROR,
"File moves beyond max. allowed depth (%d)\n", EBML_MAX_DEPTH);
return AVERROR(ENOSYS);
}
/* remember level */
level = &matroska->levels[matroska->num_levels++];
level->start = url_ftell(pb);
level->length = length;
return 0;
}
/*
* Read the next element as binary data.
* 0 is success, < 0 is failure.
*/
static int
ebml_read_binary (MatroskaDemuxContext *matroska,
uint32_t *id,
uint8_t **binary,
int *size)
{
ByteIOContext *pb = matroska->ctx->pb;
uint64_t rlength;
int res;
if ((res = ebml_read_element_id(matroska, id, NULL)) < 0 ||
(res = ebml_read_element_length(matroska, &rlength)) < 0)
return res;
*size = rlength;
if (!(*binary = av_malloc(*size))) {
av_log(matroska->ctx, AV_LOG_ERROR,
"Memory allocation error\n");
return AVERROR(ENOMEM);
}
if (get_buffer(pb, *binary, *size) != *size) {
offset_t pos = url_ftell(pb);
av_log(matroska->ctx, AV_LOG_ERROR,
"Read error at pos. %"PRIu64" (0x%"PRIx64")\n", pos, pos);
return AVERROR(EIO);
}
return 0;
}
/*
* Read signed/unsigned "EBML" numbers.
* Return: number of bytes processed, < 0 on error.
* XXX: use ebml_read_num().
*/
static int
matroska_ebmlnum_uint (uint8_t *data,
uint32_t size,
uint64_t *num)
{
int len_mask = 0x80, read = 1, n = 1, num_ffs = 0;
uint64_t total;
if (size <= 0)
return AVERROR_INVALIDDATA;
total = data[0];
while (read <= 8 && !(total & len_mask)) {
read++;
len_mask >>= 1;
}
if (read > 8)
return AVERROR_INVALIDDATA;
if ((total &= (len_mask - 1)) == len_mask - 1)
num_ffs++;
if (size < read)
return AVERROR_INVALIDDATA;
while (n < read) {
if (data[n] == 0xff)
num_ffs++;
total = (total << 8) | data[n];
n++;
}
if (read == num_ffs)
*num = (uint64_t)-1;
else
*num = total;
return read;
}
/*
* Same as above, but signed.
*/
static int
matroska_ebmlnum_sint (uint8_t *data,
uint32_t size,
int64_t *num)
{
uint64_t unum;
int res;
/* read as unsigned number first */
if ((res = matroska_ebmlnum_uint(data, size, &unum)) < 0)
return res;
/* make signed (weird way) */
if (unum == (uint64_t)-1)
*num = INT64_MAX;
else
*num = unum - ((1LL << ((7 * res) - 1)) - 1);
return res;
}
/*
* Read an EBML header.
* 0 is success, < 0 is failure.
*/
static int
ebml_read_header (MatroskaDemuxContext *matroska,
char **doctype,
int *version)
{
uint32_t id;
int level_up, res = 0;
/* default init */
if (doctype)
*doctype = NULL;
if (version)
*version = 1;
if (!(id = ebml_peek_id(matroska, &level_up)) ||
level_up != 0 || id != EBML_ID_HEADER) {
av_log(matroska->ctx, AV_LOG_ERROR,
"This is not an EBML file (id=0x%x/0x%x)\n", id, EBML_ID_HEADER);
return AVERROR_INVALIDDATA;
}
if ((res = ebml_read_master(matroska, &id)) < 0)
return res;
while (res == 0) {
if (!(id = ebml_peek_id(matroska, &level_up)))
return AVERROR(EIO);
/* end-of-header */
if (level_up)
break;
switch (id) {
/* is our read version uptodate? */
case EBML_ID_EBMLREADVERSION: {
uint64_t num;
if ((res = ebml_read_uint(matroska, &id, &num)) < 0)
return res;
if (num > EBML_VERSION) {
av_log(matroska->ctx, AV_LOG_ERROR,
"EBML version %"PRIu64" (> %d) is not supported\n",
num, EBML_VERSION);
return AVERROR_INVALIDDATA;
}
break;
}
/* we only handle 8 byte lengths at max */
case EBML_ID_EBMLMAXSIZELENGTH: {
uint64_t num;
if ((res = ebml_read_uint(matroska, &id, &num)) < 0)
return res;
if (num > sizeof(uint64_t)) {
av_log(matroska->ctx, AV_LOG_ERROR,
"Integers of size %"PRIu64" (> %zd) not supported\n",
num, sizeof(uint64_t));
return AVERROR_INVALIDDATA;
}
break;
}
/* we handle 4 byte IDs at max */
case EBML_ID_EBMLMAXIDLENGTH: {
uint64_t num;
if ((res = ebml_read_uint(matroska, &id, &num)) < 0)
return res;
if (num > sizeof(uint32_t)) {
av_log(matroska->ctx, AV_LOG_ERROR,
"IDs of size %"PRIu64" (> %zu) not supported\n",
num, sizeof(uint32_t));
return AVERROR_INVALIDDATA;
}
break;
}
case EBML_ID_DOCTYPE: {
char *text;
if ((res = ebml_read_ascii(matroska, &id, &text)) < 0)
return res;
if (doctype) {
if (*doctype)
av_free(*doctype);
*doctype = text;
} else
av_free(text);
break;
}
case EBML_ID_DOCTYPEREADVERSION: {
uint64_t num;
if ((res = ebml_read_uint(matroska, &id, &num)) < 0)
return res;
if (version)
*version = num;
break;
}
default:
av_log(matroska->ctx, AV_LOG_INFO,
"Unknown data type 0x%x in EBML header", id);
/* pass-through */
case EBML_ID_VOID:
/* we ignore these two, as they don't tell us anything we
* care about */
case EBML_ID_EBMLVERSION:
case EBML_ID_DOCTYPEVERSION:
res = ebml_read_skip (matroska);
break;
}
}
return 0;
}
static int
matroska_find_track_by_num (MatroskaDemuxContext *matroska,
int num)
{
int i;
for (i = 0; i < matroska->num_tracks; i++)
if (matroska->tracks[i]->num == num)
return i;
return -1;
}
/*
* Put one packet in an application-supplied AVPacket struct.
* Returns 0 on success or -1 on failure.
*/
static int
matroska_deliver_packet (MatroskaDemuxContext *matroska,
AVPacket *pkt)
{
if (matroska->num_packets > 0) {
memcpy(pkt, matroska->packets[0], sizeof(AVPacket));
av_free(matroska->packets[0]);
if (matroska->num_packets > 1) {
memmove(&matroska->packets[0], &matroska->packets[1],
(matroska->num_packets - 1) * sizeof(AVPacket *));
matroska->packets =
av_realloc(matroska->packets, (matroska->num_packets - 1) *
sizeof(AVPacket *));
} else {
av_freep(&matroska->packets);
}
matroska->num_packets--;
return 0;
}
return -1;
}
/*
* Put a packet into our internal queue. Will be delivered to the
* user/application during the next get_packet() call.
*/
static void
matroska_queue_packet (MatroskaDemuxContext *matroska,
AVPacket *pkt)
{
matroska->packets =
av_realloc(matroska->packets, (matroska->num_packets + 1) *
sizeof(AVPacket *));
matroska->packets[matroska->num_packets] = pkt;
matroska->num_packets++;
}
/*
* Free all packets in our internal queue.
*/
static void
matroska_clear_queue (MatroskaDemuxContext *matroska)
{
if (matroska->packets) {
int n;
for (n = 0; n < matroska->num_packets; n++) {
av_free_packet(matroska->packets[n]);
av_free(matroska->packets[n]);
}
av_free(matroska->packets);
matroska->packets = NULL;
matroska->num_packets = 0;
}
}
/*
* Autodetecting...
*/
static int
matroska_probe (AVProbeData *p)
{
uint64_t total = 0;
int len_mask = 0x80, size = 1, n = 1;
uint8_t probe_data[] = { 'm', 'a', 't', 'r', 'o', 's', 'k', 'a' };
/* ebml header? */
if (AV_RB32(p->buf) != EBML_ID_HEADER)
return 0;
/* length of header */
total = p->buf[4];
while (size <= 8 && !(total & len_mask)) {
size++;
len_mask >>= 1;
}
if (size > 8)
return 0;
total &= (len_mask - 1);
while (n < size)
total = (total << 8) | p->buf[4 + n++];
/* does the probe data contain the whole header? */
if (p->buf_size < 4 + size + total)
return 0;
/* the header must contain the document type 'matroska'. For now,
* we don't parse the whole header but simply check for the
* availability of that array of characters inside the header.
* Not fully fool-proof, but good enough. */
for (n = 4 + size; n <= 4 + size + total - sizeof(probe_data); n++)
if (!memcmp (&p->buf[n], probe_data, sizeof(probe_data)))
return AVPROBE_SCORE_MAX;
return 0;
}
/*
* From here on, it's all XML-style DTD stuff... Needs no comments.
*/
static int
matroska_parse_info (MatroskaDemuxContext *matroska)
{
int res = 0;
uint32_t id;
av_log(matroska->ctx, AV_LOG_DEBUG, "Parsing info...\n");
while (res == 0) {
if (!(id = ebml_peek_id(matroska, &matroska->level_up))) {
res = AVERROR(EIO);
break;
} else if (matroska->level_up) {
matroska->level_up--;
break;
}
switch (id) {
/* cluster timecode */
case MATROSKA_ID_TIMECODESCALE: {
uint64_t num;
if ((res = ebml_read_uint(matroska, &id, &num)) < 0)
break;
matroska->time_scale = num;
break;
}
case MATROSKA_ID_DURATION: {
double num;
if ((res = ebml_read_float(matroska, &id, &num)) < 0)
break;
matroska->ctx->duration = num * matroska->time_scale * 1000 / AV_TIME_BASE;
break;
}
case MATROSKA_ID_TITLE: {
char *text;
if ((res = ebml_read_utf8(matroska, &id, &text)) < 0)
break;
strncpy(matroska->ctx->title, text,
sizeof(matroska->ctx->title)-1);
av_free(text);
break;
}
case MATROSKA_ID_WRITINGAPP: {
char *text;
if ((res = ebml_read_utf8(matroska, &id, &text)) < 0)
break;
matroska->writing_app = text;
break;
}
case MATROSKA_ID_MUXINGAPP: {
char *text;
if ((res = ebml_read_utf8(matroska, &id, &text)) < 0)
break;
matroska->muxing_app = text;
break;
}
case MATROSKA_ID_DATEUTC: {
int64_t time;
if ((res = ebml_read_date(matroska, &id, &time)) < 0)
break;
matroska->created = time;
break;
}
default:
av_log(matroska->ctx, AV_LOG_INFO,
"Unknown entry 0x%x in info header\n", id);
/* fall-through */
case EBML_ID_VOID:
res = ebml_read_skip(matroska);
break;
}
if (matroska->level_up) {
matroska->level_up--;
break;
}
}
return res;
}
static int
matroska_add_stream (MatroskaDemuxContext *matroska)
{
int res = 0;
uint32_t id;
MatroskaTrack *track;
av_log(matroska->ctx, AV_LOG_DEBUG, "parsing track, adding stream..,\n");
/* Allocate a generic track. As soon as we know its type we'll realloc. */
track = av_mallocz(MAX_TRACK_SIZE);
matroska->num_tracks++;
strcpy(track->language, "eng");
/* start with the master */
if ((res = ebml_read_master(matroska, &id)) < 0)
return res;
/* try reading the trackentry headers */
while (res == 0) {
if (!(id = ebml_peek_id(matroska, &matroska->level_up))) {
res = AVERROR(EIO);
break;
} else if (matroska->level_up > 0) {
matroska->level_up--;
break;
}
switch (id) {
/* track number (unique stream ID) */
case MATROSKA_ID_TRACKNUMBER: {
uint64_t num;
if ((res = ebml_read_uint(matroska, &id, &num)) < 0)
break;
track->num = num;
break;
}
/* track UID (unique identifier) */
case MATROSKA_ID_TRACKUID: {
uint64_t num;
if ((res = ebml_read_uint(matroska, &id, &num)) < 0)
break;
track->uid = num;
break;
}
/* track type (video, audio, combined, subtitle, etc.) */
case MATROSKA_ID_TRACKTYPE: {
uint64_t num;
if ((res = ebml_read_uint(matroska, &id, &num)) < 0)
break;
if (track->type && track->type != num) {
av_log(matroska->ctx, AV_LOG_INFO,
"More than one tracktype in an entry - skip\n");
break;
}
track->type = num;
switch (track->type) {
case MATROSKA_TRACK_TYPE_VIDEO:
case MATROSKA_TRACK_TYPE_AUDIO:
case MATROSKA_TRACK_TYPE_SUBTITLE:
break;
case MATROSKA_TRACK_TYPE_COMPLEX:
case MATROSKA_TRACK_TYPE_LOGO:
case MATROSKA_TRACK_TYPE_CONTROL:
default:
av_log(matroska->ctx, AV_LOG_INFO,
"Unknown or unsupported track type 0x%x\n",
track->type);
track->type = 0;
break;
}
matroska->tracks[matroska->num_tracks - 1] = track;
break;
}
/* tracktype specific stuff for video */
case MATROSKA_ID_TRACKVIDEO: {
MatroskaVideoTrack *videotrack;
if (!track->type)
track->type = MATROSKA_TRACK_TYPE_VIDEO;
if (track->type != MATROSKA_TRACK_TYPE_VIDEO) {
av_log(matroska->ctx, AV_LOG_INFO,
"video data in non-video track - ignoring\n");
res = AVERROR_INVALIDDATA;
break;
} else if ((res = ebml_read_master(matroska, &id)) < 0)
break;
videotrack = (MatroskaVideoTrack *)track;
while (res == 0) {
if (!(id = ebml_peek_id(matroska, &matroska->level_up))) {
res = AVERROR(EIO);
break;
} else if (matroska->level_up > 0) {
matroska->level_up--;
break;
}
switch (id) {
/* fixme, this should be one-up, but I get it here */
case MATROSKA_ID_TRACKDEFAULTDURATION: {
uint64_t num;
if ((res = ebml_read_uint (matroska, &id,
&num)) < 0)
break;
track->default_duration = num;
break;
}
/* video framerate */
case MATROSKA_ID_VIDEOFRAMERATE: {
double num;
if ((res = ebml_read_float(matroska, &id,
&num)) < 0)
break;
if (!track->default_duration)
track->default_duration = 1000000000/num;
break;
}
/* width of the size to display the video at */
case MATROSKA_ID_VIDEODISPLAYWIDTH: {
uint64_t num;
if ((res = ebml_read_uint(matroska, &id,
&num)) < 0)
break;
videotrack->display_width = num;
break;
}
/* height of the size to display the video at */
case MATROSKA_ID_VIDEODISPLAYHEIGHT: {
uint64_t num;
if ((res = ebml_read_uint(matroska, &id,
&num)) < 0)
break;
videotrack->display_height = num;
break;
}
/* width of the video in the file */
case MATROSKA_ID_VIDEOPIXELWIDTH: {
uint64_t num;
if ((res = ebml_read_uint(matroska, &id,
&num)) < 0)
break;
videotrack->pixel_width = num;
break;
}
/* height of the video in the file */
case MATROSKA_ID_VIDEOPIXELHEIGHT: {
uint64_t num;
if ((res = ebml_read_uint(matroska, &id,
&num)) < 0)
break;
videotrack->pixel_height = num;
break;
}
/* whether the video is interlaced */
case MATROSKA_ID_VIDEOFLAGINTERLACED: {
uint64_t num;
if ((res = ebml_read_uint(matroska, &id,
&num)) < 0)
break;
if (num)
track->flags |=
MATROSKA_VIDEOTRACK_INTERLACED;
else
track->flags &=
~MATROSKA_VIDEOTRACK_INTERLACED;
break;
}
/* stereo mode (whether the video has two streams,
* where one is for the left eye and the other for
* the right eye, which creates a 3D-like
* effect) */
case MATROSKA_ID_VIDEOSTEREOMODE: {
uint64_t num;
if ((res = ebml_read_uint(matroska, &id,
&num)) < 0)
break;
if (num != MATROSKA_EYE_MODE_MONO &&
num != MATROSKA_EYE_MODE_LEFT &&
num != MATROSKA_EYE_MODE_RIGHT &&
num != MATROSKA_EYE_MODE_BOTH) {
av_log(matroska->ctx, AV_LOG_INFO,
"Ignoring unknown eye mode 0x%x\n",
(uint32_t) num);
break;
}
videotrack->eye_mode = num;
break;
}
/* aspect ratio behaviour */
case MATROSKA_ID_VIDEOASPECTRATIO: {
uint64_t num;
if ((res = ebml_read_uint(matroska, &id,
&num)) < 0)
break;
if (num != MATROSKA_ASPECT_RATIO_MODE_FREE &&
num != MATROSKA_ASPECT_RATIO_MODE_KEEP &&
num != MATROSKA_ASPECT_RATIO_MODE_FIXED) {
av_log(matroska->ctx, AV_LOG_INFO,
"Ignoring unknown aspect ratio 0x%x\n",
(uint32_t) num);
break;
}
videotrack->ar_mode = num;
break;
}
/* colorspace (only matters for raw video)
* fourcc */
case MATROSKA_ID_VIDEOCOLORSPACE: {
uint64_t num;
if ((res = ebml_read_uint(matroska, &id,
&num)) < 0)
break;
videotrack->fourcc = num;
break;
}
default:
av_log(matroska->ctx, AV_LOG_INFO,
"Unknown video track header entry "
"0x%x - ignoring\n", id);
/* pass-through */
case EBML_ID_VOID:
res = ebml_read_skip(matroska);
break;
}
if (matroska->level_up) {
matroska->level_up--;
break;
}
}
break;
}
/* tracktype specific stuff for audio */
case MATROSKA_ID_TRACKAUDIO: {
MatroskaAudioTrack *audiotrack;
if (!track->type)
track->type = MATROSKA_TRACK_TYPE_AUDIO;
if (track->type != MATROSKA_TRACK_TYPE_AUDIO) {
av_log(matroska->ctx, AV_LOG_INFO,
"audio data in non-audio track - ignoring\n");
res = AVERROR_INVALIDDATA;
break;
} else if ((res = ebml_read_master(matroska, &id)) < 0)
break;
audiotrack = (MatroskaAudioTrack *)track;
audiotrack->channels = 1;
audiotrack->samplerate = 8000;
while (res == 0) {
if (!(id = ebml_peek_id(matroska, &matroska->level_up))) {
res = AVERROR(EIO);
break;
} else if (matroska->level_up > 0) {
matroska->level_up--;
break;
}
switch (id) {
/* samplerate */
case MATROSKA_ID_AUDIOSAMPLINGFREQ: {
double num;
if ((res = ebml_read_float(matroska, &id,
&num)) < 0)
break;
audiotrack->internal_samplerate =
audiotrack->samplerate = num;
break;
}
case MATROSKA_ID_AUDIOOUTSAMPLINGFREQ: {
double num;
if ((res = ebml_read_float(matroska, &id,
&num)) < 0)
break;
audiotrack->samplerate = num;
break;
}
/* bitdepth */
case MATROSKA_ID_AUDIOBITDEPTH: {
uint64_t num;
if ((res = ebml_read_uint(matroska, &id,
&num)) < 0)
break;
audiotrack->bitdepth = num;
break;
}
/* channels */
case MATROSKA_ID_AUDIOCHANNELS: {
uint64_t num;
if ((res = ebml_read_uint(matroska, &id,
&num)) < 0)
break;
audiotrack->channels = num;
break;
}
default:
av_log(matroska->ctx, AV_LOG_INFO,
"Unknown audio track header entry "
"0x%x - ignoring\n", id);
/* pass-through */
case EBML_ID_VOID:
res = ebml_read_skip(matroska);
break;
}
if (matroska->level_up) {
matroska->level_up--;
break;
}
}
break;
}
/* codec identifier */
case MATROSKA_ID_CODECID: {
char *text;
if ((res = ebml_read_ascii(matroska, &id, &text)) < 0)
break;
track->codec_id = text;
break;
}
/* codec private data */
case MATROSKA_ID_CODECPRIVATE: {
uint8_t *data;
int size;
if ((res = ebml_read_binary(matroska, &id, &data, &size) < 0))
break;
track->codec_priv = data;
track->codec_priv_size = size;
break;
}
/* name of the codec */
case MATROSKA_ID_CODECNAME: {
char *text;
if ((res = ebml_read_utf8(matroska, &id, &text)) < 0)
break;
track->codec_name = text;
break;
}
/* name of this track */
case MATROSKA_ID_TRACKNAME: {
char *text;
if ((res = ebml_read_utf8(matroska, &id, &text)) < 0)
break;
track->name = text;
break;
}
/* language (matters for audio/subtitles, mostly) */
case MATROSKA_ID_TRACKLANGUAGE: {
char *text, *end;
if ((res = ebml_read_utf8(matroska, &id, &text)) < 0)
break;
if ((end = strchr(text, '-')))
*end = '\0';
if (strlen(text) == 3)
strcpy(track->language, text);
av_free(text);
break;
}
/* whether this is actually used */
case MATROSKA_ID_TRACKFLAGENABLED: {
uint64_t num;
if ((res = ebml_read_uint(matroska, &id, &num)) < 0)
break;
if (num)
track->flags |= MATROSKA_TRACK_ENABLED;
else
track->flags &= ~MATROSKA_TRACK_ENABLED;
break;
}
/* whether it's the default for this track type */
case MATROSKA_ID_TRACKFLAGDEFAULT: {
uint64_t num;
if ((res = ebml_read_uint(matroska, &id, &num)) < 0)
break;
if (num)
track->flags |= MATROSKA_TRACK_DEFAULT;
else
track->flags &= ~MATROSKA_TRACK_DEFAULT;
break;
}
/* lacing (like MPEG, where blocks don't end/start on frame
* boundaries) */
case MATROSKA_ID_TRACKFLAGLACING: {
uint64_t num;
if ((res = ebml_read_uint(matroska, &id, &num)) < 0)
break;
if (num)
track->flags |= MATROSKA_TRACK_LACING;
else
track->flags &= ~MATROSKA_TRACK_LACING;
break;
}
/* default length (in time) of one data block in this track */
case MATROSKA_ID_TRACKDEFAULTDURATION: {
uint64_t num;
if ((res = ebml_read_uint(matroska, &id, &num)) < 0)
break;
track->default_duration = num;
break;
}
default:
av_log(matroska->ctx, AV_LOG_INFO,
"Unknown track header entry 0x%x - ignoring\n", id);
/* pass-through */
case EBML_ID_VOID:
/* we ignore these because they're nothing useful. */
case MATROSKA_ID_CODECINFOURL:
case MATROSKA_ID_CODECDOWNLOADURL:
case MATROSKA_ID_TRACKMINCACHE:
case MATROSKA_ID_TRACKMAXCACHE:
res = ebml_read_skip(matroska);
break;
}
if (matroska->level_up) {
matroska->level_up--;
break;
}
}
return res;
}
static int
matroska_parse_tracks (MatroskaDemuxContext *matroska)
{
int res = 0;
uint32_t id;
av_log(matroska->ctx, AV_LOG_DEBUG, "parsing tracks...\n");
while (res == 0) {
if (!(id = ebml_peek_id(matroska, &matroska->level_up))) {
res = AVERROR(EIO);
break;
} else if (matroska->level_up) {
matroska->level_up--;
break;
}
switch (id) {
/* one track within the "all-tracks" header */
case MATROSKA_ID_TRACKENTRY:
res = matroska_add_stream(matroska);
break;
default:
av_log(matroska->ctx, AV_LOG_INFO,
"Unknown entry 0x%x in track header\n", id);
/* fall-through */
case EBML_ID_VOID:
res = ebml_read_skip(matroska);
break;
}
if (matroska->level_up) {
matroska->level_up--;
break;
}
}
return res;
}
static int
matroska_parse_index (MatroskaDemuxContext *matroska)
{
int res = 0;
uint32_t id;
MatroskaDemuxIndex idx;
av_log(matroska->ctx, AV_LOG_DEBUG, "parsing index...\n");
while (res == 0) {
if (!(id = ebml_peek_id(matroska, &matroska->level_up))) {
res = AVERROR(EIO);
break;
} else if (matroska->level_up) {
matroska->level_up--;
break;
}
switch (id) {
/* one single index entry ('point') */
case MATROSKA_ID_POINTENTRY:
if ((res = ebml_read_master(matroska, &id)) < 0)
break;
/* in the end, we hope to fill one entry with a
* timestamp, a file position and a tracknum */
idx.pos = (uint64_t) -1;
idx.time = (uint64_t) -1;
idx.track = (uint16_t) -1;
while (res == 0) {
if (!(id = ebml_peek_id(matroska, &matroska->level_up))) {
res = AVERROR(EIO);
break;
} else if (matroska->level_up) {
matroska->level_up--;
break;
}
switch (id) {
/* one single index entry ('point') */
case MATROSKA_ID_CUETIME: {
uint64_t time;
if ((res = ebml_read_uint(matroska, &id,
&time)) < 0)
break;
idx.time = time * matroska->time_scale;
break;
}
/* position in the file + track to which it
* belongs */
case MATROSKA_ID_CUETRACKPOSITION:
if ((res = ebml_read_master(matroska, &id)) < 0)
break;
while (res == 0) {
if (!(id = ebml_peek_id (matroska,
&matroska->level_up))) {
res = AVERROR(EIO);
break;
} else if (matroska->level_up) {
matroska->level_up--;
break;
}
switch (id) {
/* track number */
case MATROSKA_ID_CUETRACK: {
uint64_t num;
if ((res = ebml_read_uint(matroska,
&id, &num)) < 0)
break;
idx.track = num;
break;
}
/* position in file */
case MATROSKA_ID_CUECLUSTERPOSITION: {
uint64_t num;
if ((res = ebml_read_uint(matroska,
&id, &num)) < 0)
break;
idx.pos = num+matroska->segment_start;
break;
}
default:
av_log(matroska->ctx, AV_LOG_INFO,
"Unknown entry 0x%x in "
"CuesTrackPositions\n", id);
/* fall-through */
case EBML_ID_VOID:
res = ebml_read_skip(matroska);
break;
}
if (matroska->level_up) {
matroska->level_up--;
break;
}
}
break;
default:
av_log(matroska->ctx, AV_LOG_INFO,
"Unknown entry 0x%x in cuespoint "
"index\n", id);
/* fall-through */
case EBML_ID_VOID:
res = ebml_read_skip(matroska);
break;
}
if (matroska->level_up) {
matroska->level_up--;
break;
}
}
/* so let's see if we got what we wanted */
if (idx.pos != (uint64_t) -1 &&
idx.time != (uint64_t) -1 &&
idx.track != (uint16_t) -1) {
if (matroska->num_indexes % 32 == 0) {
/* re-allocate bigger index */
matroska->index =
av_realloc(matroska->index,
(matroska->num_indexes + 32) *
sizeof(MatroskaDemuxIndex));
}
matroska->index[matroska->num_indexes] = idx;
matroska->num_indexes++;
}
break;
default:
av_log(matroska->ctx, AV_LOG_INFO,
"Unknown entry 0x%x in cues header\n", id);
/* fall-through */
case EBML_ID_VOID:
res = ebml_read_skip(matroska);
break;
}
if (matroska->level_up) {
matroska->level_up--;
break;
}
}
return res;
}
static int
matroska_parse_metadata (MatroskaDemuxContext *matroska)
{
int res = 0;
uint32_t id;
while (res == 0) {
if (!(id = ebml_peek_id(matroska, &matroska->level_up))) {
res = AVERROR(EIO);
break;
} else if (matroska->level_up) {
matroska->level_up--;
break;
}
switch (id) {
/* Hm, this is unsupported... */
default:
av_log(matroska->ctx, AV_LOG_INFO,
"Unknown entry 0x%x in metadata header\n", id);
/* fall-through */
case EBML_ID_VOID:
res = ebml_read_skip(matroska);
break;
}
if (matroska->level_up) {
matroska->level_up--;
break;
}
}
return res;
}
static int
matroska_parse_seekhead (MatroskaDemuxContext *matroska)
{
int res = 0;
uint32_t id;
av_log(matroska->ctx, AV_LOG_DEBUG, "parsing seekhead...\n");
while (res == 0) {
if (!(id = ebml_peek_id(matroska, &matroska->level_up))) {
res = AVERROR(EIO);
break;
} else if (matroska->level_up) {
matroska->level_up--;
break;
}
switch (id) {
case MATROSKA_ID_SEEKENTRY: {
uint32_t seek_id = 0, peek_id_cache = 0;
uint64_t seek_pos = (uint64_t) -1, t;
if ((res = ebml_read_master(matroska, &id)) < 0)
break;
while (res == 0) {
if (!(id = ebml_peek_id(matroska, &matroska->level_up))) {
res = AVERROR(EIO);
break;
} else if (matroska->level_up) {
matroska->level_up--;
break;
}
switch (id) {
case MATROSKA_ID_SEEKID:
res = ebml_read_uint(matroska, &id, &t);
seek_id = t;
break;
case MATROSKA_ID_SEEKPOSITION:
res = ebml_read_uint(matroska, &id, &seek_pos);
break;
default:
av_log(matroska->ctx, AV_LOG_INFO,
"Unknown seekhead ID 0x%x\n", id);
/* fall-through */
case EBML_ID_VOID:
res = ebml_read_skip(matroska);
break;
}
if (matroska->level_up) {
matroska->level_up--;
break;
}
}
if (!seek_id || seek_pos == (uint64_t) -1) {
av_log(matroska->ctx, AV_LOG_INFO,
"Incomplete seekhead entry (0x%x/%"PRIu64")\n",
seek_id, seek_pos);
break;
}
switch (seek_id) {
case MATROSKA_ID_CUES:
case MATROSKA_ID_TAGS: {
uint32_t level_up = matroska->level_up;
offset_t before_pos;
uint64_t length;
MatroskaLevel level;
/* remember the peeked ID and the current position */
peek_id_cache = matroska->peek_id;
before_pos = url_ftell(matroska->ctx->pb);
/* seek */
if ((res = ebml_read_seek(matroska, seek_pos +
matroska->segment_start)) < 0)
return res;
/* we don't want to lose our seekhead level, so we add
* a dummy. This is a crude hack. */
if (matroska->num_levels == EBML_MAX_DEPTH) {
av_log(matroska->ctx, AV_LOG_INFO,
"Max EBML element depth (%d) reached, "
"cannot parse further.\n", EBML_MAX_DEPTH);
return AVERROR_UNKNOWN;
}
level.start = 0;
level.length = (uint64_t)-1;
matroska->levels[matroska->num_levels] = level;
matroska->num_levels++;
/* check ID */
if (!(id = ebml_peek_id (matroska,
&matroska->level_up)))
goto finish;
if (id != seek_id) {
av_log(matroska->ctx, AV_LOG_INFO,
"We looked for ID=0x%x but got "
"ID=0x%x (pos=%"PRIu64")",
seek_id, id, seek_pos +
matroska->segment_start);
goto finish;
}
/* read master + parse */
if ((res = ebml_read_master(matroska, &id)) < 0)
goto finish;
switch (id) {
case MATROSKA_ID_CUES:
if (!(res = matroska_parse_index(matroska)) ||
url_feof(matroska->ctx->pb)) {
matroska->index_parsed = 1;
res = 0;
}
break;
case MATROSKA_ID_TAGS:
if (!(res = matroska_parse_metadata(matroska)) ||
url_feof(matroska->ctx->pb)) {
matroska->metadata_parsed = 1;
res = 0;
}
break;
}
finish:
/* remove dummy level */
while (matroska->num_levels) {
matroska->num_levels--;
length =
matroska->levels[matroska->num_levels].length;
if (length == (uint64_t)-1)
break;
}
/* seek back */
if ((res = ebml_read_seek(matroska, before_pos)) < 0)
return res;
matroska->peek_id = peek_id_cache;
matroska->level_up = level_up;
break;
}
default:
av_log(matroska->ctx, AV_LOG_INFO,
"Ignoring seekhead entry for ID=0x%x\n",
seek_id);
break;
}
break;
}
default:
av_log(matroska->ctx, AV_LOG_INFO,
"Unknown seekhead ID 0x%x\n", id);
/* fall-through */
case EBML_ID_VOID:
res = ebml_read_skip(matroska);
break;
}
if (matroska->level_up) {
matroska->level_up--;
break;
}
}
return res;
}
static int
matroska_parse_attachments(AVFormatContext *s)
{
MatroskaDemuxContext *matroska = s->priv_data;
int res = 0;
uint32_t id;
av_log(matroska->ctx, AV_LOG_DEBUG, "parsing attachments...\n");
while (res == 0) {
if (!(id = ebml_peek_id(matroska, &matroska->level_up))) {
res = AVERROR(EIO);
break;
} else if (matroska->level_up) {
matroska->level_up--;
break;
}
switch (id) {
case MATROSKA_ID_ATTACHEDFILE: {
char* name = NULL;
char* mime = NULL;
uint8_t* data = NULL;
int i, data_size = 0;
AVStream *st;
if ((res = ebml_read_master(matroska, &id)) < 0)
break;
while (res == 0) {
if (!(id = ebml_peek_id(matroska, &matroska->level_up))) {
res = AVERROR(EIO);
break;
} else if (matroska->level_up) {
matroska->level_up--;
break;
}
switch (id) {
case MATROSKA_ID_FILENAME:
res = ebml_read_utf8 (matroska, &id, &name);
break;
case MATROSKA_ID_FILEMIMETYPE:
res = ebml_read_ascii (matroska, &id, &mime);
break;
case MATROSKA_ID_FILEDATA:
res = ebml_read_binary(matroska, &id, &data, &data_size);
break;
default:
av_log(matroska->ctx, AV_LOG_INFO,
"Unknown attachedfile ID 0x%x\n", id);
case EBML_ID_VOID:
res = ebml_read_skip(matroska);
break;
}
if (matroska->level_up) {
matroska->level_up--;
break;
}
}
if (!(name && mime && data && data_size > 0)) {
av_log(matroska->ctx, AV_LOG_ERROR, "incomplete attachment\n");
break;
}
st = av_new_stream(s, matroska->num_streams++);
if (st == NULL)
return AVERROR(ENOMEM);
st->filename = av_strdup(name);
st->codec->codec_id = CODEC_ID_NONE;
st->codec->codec_type = CODEC_TYPE_ATTACHMENT;
st->codec->extradata = av_malloc(data_size);
if(st->codec->extradata == NULL)
return AVERROR(ENOMEM);
st->codec->extradata_size = data_size;
memcpy(st->codec->extradata, data, data_size);
for (i=0; ff_mkv_mime_tags[i].id != CODEC_ID_NONE; i++) {
if (!strncmp(ff_mkv_mime_tags[i].str, mime,
strlen(ff_mkv_mime_tags[i].str))) {
st->codec->codec_id = ff_mkv_mime_tags[i].id;
break;
}
}
av_log(matroska->ctx, AV_LOG_DEBUG, "new attachment: %s, %s, size %d \n", name, mime, data_size);
break;
}
default:
av_log(matroska->ctx, AV_LOG_INFO,
"Unknown attachments ID 0x%x\n", id);
/* fall-through */
case EBML_ID_VOID:
res = ebml_read_skip(matroska);
break;
}
if (matroska->level_up) {
matroska->level_up--;
break;
}
}
return res;
}
#define ARRAY_SIZE(x) (sizeof(x)/sizeof(*x))
static int
matroska_aac_profile (char *codec_id)
{
static const char *aac_profiles[] = {
"MAIN", "LC", "SSR"
};
int profile;
for (profile=0; profile<ARRAY_SIZE(aac_profiles); profile++)
if (strstr(codec_id, aac_profiles[profile]))
break;
return profile + 1;
}
static int
matroska_aac_sri (int samplerate)
{
static const int aac_sample_rates[] = {
96000, 88200, 64000, 48000, 44100, 32000,
24000, 22050, 16000, 12000, 11025, 8000,
};
int sri;
for (sri=0; sri<ARRAY_SIZE(aac_sample_rates); sri++)
if (aac_sample_rates[sri] == samplerate)
break;
return sri;
}
static int
matroska_read_header (AVFormatContext *s,
AVFormatParameters *ap)
{
MatroskaDemuxContext *matroska = s->priv_data;
char *doctype;
int version, last_level, res = 0;
uint32_t id;
matroska->ctx = s;
/* First read the EBML header. */
doctype = NULL;
if ((res = ebml_read_header(matroska, &doctype, &version)) < 0)
return res;
if ((doctype == NULL) || strcmp(doctype, "matroska")) {
av_log(matroska->ctx, AV_LOG_ERROR,
"Wrong EBML doctype ('%s' != 'matroska').\n",
doctype ? doctype : "(none)");
if (doctype)
av_free(doctype);
return AVERROR_NOFMT;
}
av_free(doctype);
if (version > 2) {
av_log(matroska->ctx, AV_LOG_ERROR,
"Matroska demuxer version 2 too old for file version %d\n",
version);
return AVERROR_NOFMT;
}
/* The next thing is a segment. */
while (1) {
if (!(id = ebml_peek_id(matroska, &last_level)))
return AVERROR(EIO);
if (id == MATROSKA_ID_SEGMENT)
break;
/* oi! */
av_log(matroska->ctx, AV_LOG_INFO,
"Expected a Segment ID (0x%x), but received 0x%x!\n",
MATROSKA_ID_SEGMENT, id);
if ((res = ebml_read_skip(matroska)) < 0)
return res;
}
/* We now have a Matroska segment.
* Seeks are from the beginning of the segment,
* after the segment ID/length. */
if ((res = ebml_read_master(matroska, &id)) < 0)
return res;
matroska->segment_start = url_ftell(s->pb);
matroska->time_scale = 1000000;
/* we've found our segment, start reading the different contents in here */
while (res == 0) {
if (!(id = ebml_peek_id(matroska, &matroska->level_up))) {
res = AVERROR(EIO);
break;
} else if (matroska->level_up) {
matroska->level_up--;
break;
}
switch (id) {
/* stream info */
case MATROSKA_ID_INFO: {
if ((res = ebml_read_master(matroska, &id)) < 0)
break;
res = matroska_parse_info(matroska);
break;
}
/* track info headers */
case MATROSKA_ID_TRACKS: {
if ((res = ebml_read_master(matroska, &id)) < 0)
break;
res = matroska_parse_tracks(matroska);
break;
}
/* stream index */
case MATROSKA_ID_CUES: {
if (!matroska->index_parsed) {
if ((res = ebml_read_master(matroska, &id)) < 0)
break;
res = matroska_parse_index(matroska);
} else
res = ebml_read_skip(matroska);
break;
}
/* metadata */
case MATROSKA_ID_TAGS: {
if (!matroska->metadata_parsed) {
if ((res = ebml_read_master(matroska, &id)) < 0)
break;
res = matroska_parse_metadata(matroska);
} else
res = ebml_read_skip(matroska);
break;
}
/* file index (if seekable, seek to Cues/Tags to parse it) */
case MATROSKA_ID_SEEKHEAD: {
if ((res = ebml_read_master(matroska, &id)) < 0)
break;
res = matroska_parse_seekhead(matroska);
break;
}
case MATROSKA_ID_ATTACHMENTS: {
if ((res = ebml_read_master(matroska, &id)) < 0)
break;
res = matroska_parse_attachments(s);
break;
}
case MATROSKA_ID_CLUSTER: {
/* Do not read the master - this will be done in the next
* call to matroska_read_packet. */
res = 1;
break;
}
default:
av_log(matroska->ctx, AV_LOG_INFO,
"Unknown matroska file header ID 0x%x\n", id);
/* fall-through */
case EBML_ID_VOID:
res = ebml_read_skip(matroska);
break;
}
if (matroska->level_up) {
matroska->level_up--;
break;
}
}
/* Have we found a cluster? */
if (ebml_peek_id(matroska, NULL) == MATROSKA_ID_CLUSTER) {
int i, j;
MatroskaTrack *track;
AVStream *st;
for (i = 0; i < matroska->num_tracks; i++) {
enum CodecID codec_id = CODEC_ID_NONE;
uint8_t *extradata = NULL;
int extradata_size = 0;
int extradata_offset = 0;
track = matroska->tracks[i];
track->stream_index = -1;
/* Apply some sanity checks. */
if (track->codec_id == NULL)
continue;
for(j=0; ff_mkv_codec_tags[j].id != CODEC_ID_NONE; j++){
if(!strncmp(ff_mkv_codec_tags[j].str, track->codec_id,
strlen(ff_mkv_codec_tags[j].str))){
codec_id= ff_mkv_codec_tags[j].id;
break;
}
}
/* Set the FourCC from the CodecID. */
/* This is the MS compatibility mode which stores a
* BITMAPINFOHEADER in the CodecPrivate. */
if (!strcmp(track->codec_id,
MATROSKA_CODEC_ID_VIDEO_VFW_FOURCC) &&
(track->codec_priv_size >= 40) &&
(track->codec_priv != NULL)) {
MatroskaVideoTrack *vtrack = (MatroskaVideoTrack *) track;
/* Offset of biCompression. Stored in LE. */
vtrack->fourcc = AV_RL32(track->codec_priv + 16);
codec_id = codec_get_id(codec_bmp_tags, vtrack->fourcc);
}
/* This is the MS compatibility mode which stores a
* WAVEFORMATEX in the CodecPrivate. */
else if (!strcmp(track->codec_id,
MATROSKA_CODEC_ID_AUDIO_ACM) &&
(track->codec_priv_size >= 18) &&
(track->codec_priv != NULL)) {
uint16_t tag;
/* Offset of wFormatTag. Stored in LE. */
tag = AV_RL16(track->codec_priv);
codec_id = codec_get_id(codec_wav_tags, tag);
}
else if (codec_id == CODEC_ID_AAC && !track->codec_priv_size) {
MatroskaAudioTrack *audiotrack = (MatroskaAudioTrack *) track;
int profile = matroska_aac_profile(track->codec_id);
int sri = matroska_aac_sri(audiotrack->internal_samplerate);
extradata = av_malloc(5);
if (extradata == NULL)
return AVERROR(ENOMEM);
extradata[0] = (profile << 3) | ((sri&0x0E) >> 1);
extradata[1] = ((sri&0x01) << 7) | (audiotrack->channels<<3);
if (strstr(track->codec_id, "SBR")) {
sri = matroska_aac_sri(audiotrack->samplerate);
extradata[2] = 0x56;
extradata[3] = 0xE5;
extradata[4] = 0x80 | (sri<<3);
extradata_size = 5;
} else {
extradata_size = 2;
}
}
else if (codec_id == CODEC_ID_TTA) {
MatroskaAudioTrack *audiotrack = (MatroskaAudioTrack *) track;
ByteIOContext b;
extradata_size = 30;
extradata = av_mallocz(extradata_size);
if (extradata == NULL)
return AVERROR(ENOMEM);
init_put_byte(&b, extradata, extradata_size, 1,
NULL, NULL, NULL, NULL);
put_buffer(&b, "TTA1", 4);
put_le16(&b, 1);
put_le16(&b, audiotrack->channels);
put_le16(&b, audiotrack->bitdepth);
put_le32(&b, audiotrack->samplerate);
put_le32(&b, matroska->ctx->duration * audiotrack->samplerate);
}
else if (codec_id == CODEC_ID_RV10 || codec_id == CODEC_ID_RV20 ||
codec_id == CODEC_ID_RV30 || codec_id == CODEC_ID_RV40) {
extradata_offset = 26;
track->codec_priv_size -= extradata_offset;
}
else if (codec_id == CODEC_ID_RA_144) {
MatroskaAudioTrack *audiotrack = (MatroskaAudioTrack *)track;
audiotrack->samplerate = 8000;
audiotrack->channels = 1;
}
else if (codec_id == CODEC_ID_RA_288 ||
codec_id == CODEC_ID_COOK ||
codec_id == CODEC_ID_ATRAC3) {
MatroskaAudioTrack *audiotrack = (MatroskaAudioTrack *)track;
ByteIOContext b;
init_put_byte(&b, track->codec_priv, track->codec_priv_size, 0,
NULL, NULL, NULL, NULL);
url_fskip(&b, 24);
audiotrack->coded_framesize = get_be32(&b);
url_fskip(&b, 12);
audiotrack->sub_packet_h = get_be16(&b);
audiotrack->frame_size = get_be16(&b);
audiotrack->sub_packet_size = get_be16(&b);
audiotrack->buf = av_malloc(audiotrack->frame_size * audiotrack->sub_packet_h);
if (codec_id == CODEC_ID_RA_288) {
audiotrack->block_align = audiotrack->coded_framesize;
track->codec_priv_size = 0;
} else {
audiotrack->block_align = audiotrack->sub_packet_size;
extradata_offset = 78;
track->codec_priv_size -= extradata_offset;
}
}
if (codec_id == CODEC_ID_NONE) {
av_log(matroska->ctx, AV_LOG_INFO,
"Unknown/unsupported CodecID %s.\n",
track->codec_id);
}
track->stream_index = matroska->num_streams;
matroska->num_streams++;
st = av_new_stream(s, track->stream_index);
if (st == NULL)
return AVERROR(ENOMEM);
av_set_pts_info(st, 64, matroska->time_scale, 1000*1000*1000); /* 64 bit pts in ns */
st->codec->codec_id = codec_id;
st->start_time = 0;
if (strcmp(track->language, "und"))
strcpy(st->language, track->language);
if (track->flags & MATROSKA_TRACK_DEFAULT)
st->disposition |= AV_DISPOSITION_DEFAULT;
if (track->default_duration)
av_reduce(&st->codec->time_base.num, &st->codec->time_base.den,
track->default_duration, 1000000000, 30000);
if(extradata){
st->codec->extradata = extradata;
st->codec->extradata_size = extradata_size;
} else if(track->codec_priv && track->codec_priv_size > 0){
st->codec->extradata = av_malloc(track->codec_priv_size);
if(st->codec->extradata == NULL)
return AVERROR(ENOMEM);
st->codec->extradata_size = track->codec_priv_size;
memcpy(st->codec->extradata,track->codec_priv+extradata_offset,
track->codec_priv_size);
}
if (track->type == MATROSKA_TRACK_TYPE_VIDEO) {
MatroskaVideoTrack *videotrack = (MatroskaVideoTrack *)track;
st->codec->codec_type = CODEC_TYPE_VIDEO;
st->codec->codec_tag = videotrack->fourcc;
st->codec->width = videotrack->pixel_width;
st->codec->height = videotrack->pixel_height;
if (videotrack->display_width == 0)
videotrack->display_width= videotrack->pixel_width;
if (videotrack->display_height == 0)
videotrack->display_height= videotrack->pixel_height;
av_reduce(&st->codec->sample_aspect_ratio.num,
&st->codec->sample_aspect_ratio.den,
st->codec->height * videotrack->display_width,
st->codec-> width * videotrack->display_height,
255);
st->need_parsing = AVSTREAM_PARSE_HEADERS;
} else if (track->type == MATROSKA_TRACK_TYPE_AUDIO) {
MatroskaAudioTrack *audiotrack = (MatroskaAudioTrack *)track;
st->codec->codec_type = CODEC_TYPE_AUDIO;
st->codec->sample_rate = audiotrack->samplerate;
st->codec->channels = audiotrack->channels;
st->codec->block_align = audiotrack->block_align;
} else if (track->type == MATROSKA_TRACK_TYPE_SUBTITLE) {
st->codec->codec_type = CODEC_TYPE_SUBTITLE;
}
/* What do we do with private data? E.g. for Vorbis. */
}
res = 0;
}
if (matroska->index_parsed) {
int i, track, stream;
for (i=0; i<matroska->num_indexes; i++) {
MatroskaDemuxIndex *idx = &matroska->index[i];
track = matroska_find_track_by_num(matroska, idx->track);
if (track < 0) continue;
stream = matroska->tracks[track]->stream_index;
if (stream >= 0 && stream < matroska->ctx->nb_streams)
av_add_index_entry(matroska->ctx->streams[stream],
idx->pos, idx->time/matroska->time_scale,
0, 0, AVINDEX_KEYFRAME);
}
}
return res;
}
static int
matroska_parse_block(MatroskaDemuxContext *matroska, uint8_t *data, int size,
int64_t pos, uint64_t cluster_time, uint64_t duration,
int is_keyframe, int is_bframe)
{
int res = 0;
int track;
AVStream *st;
AVPacket *pkt;
uint8_t *origdata = data;
int16_t block_time;
uint32_t *lace_size = NULL;
int n, flags, laces = 0;
uint64_t num;
int stream_index;
/* first byte(s): tracknum */
if ((n = matroska_ebmlnum_uint(data, size, &num)) < 0) {
av_log(matroska->ctx, AV_LOG_ERROR, "EBML block data error\n");
av_free(origdata);
return res;
}
data += n;
size -= n;
/* fetch track from num */
track = matroska_find_track_by_num(matroska, num);
if (size <= 3 || track < 0 || track >= matroska->num_tracks) {
av_log(matroska->ctx, AV_LOG_INFO,
"Invalid stream %d or size %u\n", track, size);
av_free(origdata);
return res;
}
stream_index = matroska->tracks[track]->stream_index;
if (stream_index < 0 || stream_index >= matroska->ctx->nb_streams) {
av_free(origdata);
return res;
}
st = matroska->ctx->streams[stream_index];
if (st->discard >= AVDISCARD_ALL) {
av_free(origdata);
return res;
}
if (duration == AV_NOPTS_VALUE)
duration = matroska->tracks[track]->default_duration / matroska->time_scale;
/* block_time (relative to cluster time) */
block_time = AV_RB16(data);
data += 2;
flags = *data++;
size -= 3;
if (is_keyframe == -1)
is_keyframe = flags & 0x80 ? PKT_FLAG_KEY : 0;
if (matroska->skip_to_keyframe) {
if (!is_keyframe || st != matroska->skip_to_stream) {
av_free(origdata);
return res;
}
matroska->skip_to_keyframe = 0;
}
switch ((flags & 0x06) >> 1) {
case 0x0: /* no lacing */
laces = 1;
lace_size = av_mallocz(sizeof(int));
lace_size[0] = size;
break;
case 0x1: /* xiph lacing */
case 0x2: /* fixed-size lacing */
case 0x3: /* EBML lacing */
if (size == 0) {
res = -1;
break;
}
laces = (*data) + 1;
data += 1;
size -= 1;
lace_size = av_mallocz(laces * sizeof(int));
switch ((flags & 0x06) >> 1) {
case 0x1: /* xiph lacing */ {
uint8_t temp;
uint32_t total = 0;
for (n = 0; res == 0 && n < laces - 1; n++) {
while (1) {
if (size == 0) {
res = -1;
break;
}
temp = *data;
lace_size[n] += temp;
data += 1;
size -= 1;
if (temp != 0xff)
break;
}
total += lace_size[n];
}
lace_size[n] = size - total;
break;
}
case 0x2: /* fixed-size lacing */
for (n = 0; n < laces; n++)
lace_size[n] = size / laces;
break;
case 0x3: /* EBML lacing */ {
uint32_t total;
n = matroska_ebmlnum_uint(data, size, &num);
if (n < 0) {
av_log(matroska->ctx, AV_LOG_INFO,
"EBML block data error\n");
break;
}
data += n;
size -= n;
total = lace_size[0] = num;
for (n = 1; res == 0 && n < laces - 1; n++) {
int64_t snum;
int r;
r = matroska_ebmlnum_sint (data, size, &snum);
if (r < 0) {
av_log(matroska->ctx, AV_LOG_INFO,
"EBML block data error\n");
break;
}
data += r;
size -= r;
lace_size[n] = lace_size[n - 1] + snum;
total += lace_size[n];
}
lace_size[n] = size - total;
break;
}
}
break;
}
if (res == 0) {
uint64_t timecode = AV_NOPTS_VALUE;
if (cluster_time != (uint64_t)-1
&& (block_time >= 0 || cluster_time >= -block_time))
timecode = cluster_time + block_time;
for (n = 0; n < laces; n++) {
if (st->codec->codec_id == CODEC_ID_RA_288 ||
st->codec->codec_id == CODEC_ID_COOK ||
st->codec->codec_id == CODEC_ID_ATRAC3) {
MatroskaAudioTrack *audiotrack = (MatroskaAudioTrack *)matroska->tracks[track];
int a = st->codec->block_align;
int sps = audiotrack->sub_packet_size;
int cfs = audiotrack->coded_framesize;
int h = audiotrack->sub_packet_h;
int y = audiotrack->sub_packet_cnt;
int w = audiotrack->frame_size;
int x;
if (!audiotrack->pkt_cnt) {
if (st->codec->codec_id == CODEC_ID_RA_288)
for (x=0; x<h/2; x++)
memcpy(audiotrack->buf+x*2*w+y*cfs,
data+x*cfs, cfs);
else
for (x=0; x<w/sps; x++)
memcpy(audiotrack->buf+sps*(h*x+((h+1)/2)*(y&1)+(y>>1)), data+x*sps, sps);
if (++audiotrack->sub_packet_cnt >= h) {
audiotrack->sub_packet_cnt = 0;
audiotrack->pkt_cnt = h*w / a;
}
}
while (audiotrack->pkt_cnt) {
pkt = av_mallocz(sizeof(AVPacket));
av_new_packet(pkt, a);
memcpy(pkt->data, audiotrack->buf
+ a * (h*w / a - audiotrack->pkt_cnt--), a);
pkt->pos = pos;
pkt->stream_index = stream_index;
matroska_queue_packet(matroska, pkt);
}
} else {
int offset = 0;
pkt = av_mallocz(sizeof(AVPacket));
/* XXX: prevent data copy... */
if (av_new_packet(pkt, lace_size[n]-offset) < 0) {
res = AVERROR(ENOMEM);
n = laces-1;
break;
}
memcpy (pkt->data, data+offset, lace_size[n]-offset);
if (n == 0)
pkt->flags = is_keyframe;
pkt->stream_index = stream_index;
pkt->pts = timecode;
pkt->pos = pos;
pkt->duration = duration;
matroska_queue_packet(matroska, pkt);
}
if (timecode != AV_NOPTS_VALUE)
timecode = duration ? timecode + duration : AV_NOPTS_VALUE;
data += lace_size[n];
}
}
av_free(lace_size);
av_free(origdata);
return res;
}
static int
matroska_parse_blockgroup (MatroskaDemuxContext *matroska,
uint64_t cluster_time)
{
int res = 0;
uint32_t id;
int is_bframe = 0;
int is_keyframe = PKT_FLAG_KEY, last_num_packets = matroska->num_packets;
uint64_t duration = AV_NOPTS_VALUE;
uint8_t *data;
int size = 0;
int64_t pos = 0;
av_log(matroska->ctx, AV_LOG_DEBUG, "parsing blockgroup...\n");
while (res == 0) {
if (!(id = ebml_peek_id(matroska, &matroska->level_up))) {
res = AVERROR(EIO);
break;
} else if (matroska->level_up) {
matroska->level_up--;
break;
}
switch (id) {
/* one block inside the group. Note, block parsing is one
* of the harder things, so this code is a bit complicated.
* See http://www.matroska.org/ for documentation. */
case MATROSKA_ID_BLOCK: {
pos = url_ftell(matroska->ctx->pb);
res = ebml_read_binary(matroska, &id, &data, &size);
break;
}
case MATROSKA_ID_BLOCKDURATION: {
if ((res = ebml_read_uint(matroska, &id, &duration)) < 0)
break;
break;
}
case MATROSKA_ID_BLOCKREFERENCE: {
int64_t num;
/* We've found a reference, so not even the first frame in
* the lace is a key frame. */
is_keyframe = 0;
if (last_num_packets != matroska->num_packets)
matroska->packets[last_num_packets]->flags = 0;
if ((res = ebml_read_sint(matroska, &id, &num)) < 0)
break;
if (num > 0)
is_bframe = 1;
break;
}
default:
av_log(matroska->ctx, AV_LOG_INFO,
"Unknown entry 0x%x in blockgroup data\n", id);
/* fall-through */
case EBML_ID_VOID:
res = ebml_read_skip(matroska);
break;
}
if (matroska->level_up) {
matroska->level_up--;
break;
}
}
if (res)
return res;
if (size > 0)
res = matroska_parse_block(matroska, data, size, pos, cluster_time,
duration, is_keyframe, is_bframe);
return res;
}
static int
matroska_parse_cluster (MatroskaDemuxContext *matroska)
{
int res = 0;
uint32_t id;
uint64_t cluster_time = 0;
uint8_t *data;
int64_t pos;
int size;
av_log(matroska->ctx, AV_LOG_DEBUG,
"parsing cluster at %"PRId64"\n", url_ftell(matroska->ctx->pb));
while (res == 0) {
if (!(id = ebml_peek_id(matroska, &matroska->level_up))) {
res = AVERROR(EIO);
break;
} else if (matroska->level_up) {
matroska->level_up--;
break;
}
switch (id) {
/* cluster timecode */
case MATROSKA_ID_CLUSTERTIMECODE: {
uint64_t num;
if ((res = ebml_read_uint(matroska, &id, &num)) < 0)
break;
cluster_time = num;
break;
}
/* a group of blocks inside a cluster */
case MATROSKA_ID_BLOCKGROUP:
if ((res = ebml_read_master(matroska, &id)) < 0)
break;
res = matroska_parse_blockgroup(matroska, cluster_time);
break;
case MATROSKA_ID_SIMPLEBLOCK:
pos = url_ftell(matroska->ctx->pb);
res = ebml_read_binary(matroska, &id, &data, &size);
if (res == 0)
res = matroska_parse_block(matroska, data, size, pos,
cluster_time, AV_NOPTS_VALUE,
-1, 0);
break;
default:
av_log(matroska->ctx, AV_LOG_INFO,
"Unknown entry 0x%x in cluster data\n", id);
/* fall-through */
case EBML_ID_VOID:
res = ebml_read_skip(matroska);
break;
}
if (matroska->level_up) {
matroska->level_up--;
break;
}
}
return res;
}
static int
matroska_read_packet (AVFormatContext *s,
AVPacket *pkt)
{
MatroskaDemuxContext *matroska = s->priv_data;
int res;
uint32_t id;
/* Read stream until we have a packet queued. */
while (matroska_deliver_packet(matroska, pkt)) {
/* Have we already reached the end? */
if (matroska->done)
return AVERROR(EIO);
res = 0;
while (res == 0) {
if (!(id = ebml_peek_id(matroska, &matroska->level_up))) {
return AVERROR(EIO);
} else if (matroska->level_up) {
matroska->level_up--;
break;
}
switch (id) {
case MATROSKA_ID_CLUSTER:
if ((res = ebml_read_master(matroska, &id)) < 0)
break;
if ((res = matroska_parse_cluster(matroska)) == 0)
res = 1; /* Parsed one cluster, let's get out. */
break;
default:
case EBML_ID_VOID:
res = ebml_read_skip(matroska);
break;
}
if (matroska->level_up) {
matroska->level_up--;
break;
}
}
if (res == -1)
matroska->done = 1;
}
return 0;
}
static int
matroska_read_seek (AVFormatContext *s, int stream_index, int64_t timestamp,
int flags)
{
MatroskaDemuxContext *matroska = s->priv_data;
AVStream *st = s->streams[stream_index];
int index;
/* find index entry */
index = av_index_search_timestamp(st, timestamp, flags);
if (index < 0)
return 0;
matroska_clear_queue(matroska);
/* do the seek */
url_fseek(s->pb, st->index_entries[index].pos, SEEK_SET);
matroska->skip_to_keyframe = !(flags & AVSEEK_FLAG_ANY);
matroska->skip_to_stream = st;
matroska->peek_id = 0;
return 0;
}
static int
matroska_read_close (AVFormatContext *s)
{
MatroskaDemuxContext *matroska = s->priv_data;
int n = 0;
av_free(matroska->writing_app);
av_free(matroska->muxing_app);
av_free(matroska->index);
matroska_clear_queue(matroska);
for (n = 0; n < matroska->num_tracks; n++) {
MatroskaTrack *track = matroska->tracks[n];
av_free(track->codec_id);
av_free(track->codec_name);
av_free(track->codec_priv);
av_free(track->name);
if (track->type == MATROSKA_TRACK_TYPE_AUDIO) {
MatroskaAudioTrack *audiotrack = (MatroskaAudioTrack *)track;
av_free(audiotrack->buf);
}
av_free(track);
}
return 0;
}
AVInputFormat matroska_demuxer = {
"matroska",
"Matroska file format",
sizeof(MatroskaDemuxContext),
matroska_probe,
matroska_read_header,
matroska_read_packet,
matroska_read_close,
matroska_read_seek,
};