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MKVMERGE(1) User Commands MKVMERGE(1)

NAME
mkvmerge - Merge multimedia streams into a Matroska(TM) file

SYNOPSIS
mkvmerge [global options] {-o out} [options1] {file1}
[[options2] {file2}] [@optionsfile]

DESCRIPTION
This program takes the input from several media files and joins their
streams (all of them or just a selection) into a Matroska(TM) file; see
the Matroska(TM) website[1].

Important

The order of command line options is important. Please read the
section "Option order" if you're new to the program.

Global options
-v, --verbose
Increase verbosity.

-q, --quiet
Suppress status output.

-o, --output file-name
Write to the file file-name. If splitting is used then this
parameter is treated a bit differently. See the explanation for the
--split option for details.

-w, --webm
Create a WebM compliant file. This is also turned on if the output
file name's extension is "webm". This mode enforces several
restrictions. The only allowed codecs are VP8, VP9 video and Opus,
Vorbis audio tracks. Neither chapters nor tags are allowed. The
DocType header item is changed to "webm".

--title title
Sets the general title for the output file, e.g. the movie name.

--default-language language-code
Sets the default language code that will be used for tracks for
which no language is set with the --language option and for which
the source container doesn't provide a language.

The default language code is 'und' for 'undefined'.

Segment info handling (global options)
--segmentinfo filename.xml
Read segment information from a XML file. This file can contain the
segment family UID, segment UID, previous and next segment UID
elements. An example file and a DTD are included in the MKVToolNix
distribution.

See the section about segment info XML files below for details.

--segment-uid SID1,SID2,...
Sets the segment UIDs to use. This is a comma-separated list of
128bit segment UIDs in the usual UID form: hex numbers with or
without the "0x" prefix, with or without spaces, exactly 32 digits.

If SID starts with = then its rest is interpreted as the name of a
Matroska file whose segment UID is read and used.

Each file created contains one segment, and each segment has one
segment UID. If more segment UIDs are specified than segments are
created then the surplus UIDs are ignored. If fewer UIDs are
specified than segments are created then random UIDs will be
created for them.

Chapter and tag handling (global options)
--chapter-language language-code
Sets the ISO639-2 language code that is written for each chapter
entry. Defaults to 'eng'. See the section about chapters below for
details.

This option can be used both for simple chapter files and for
source files that contain chapters but no information about the
chapters' language, e.g. MP4 and OGM files.

--chapter-charset character-set
Sets the character set that is used for the conversion to UTF-8 for
simple chapter files. See the section about text files and
character sets for an explanation how mkvmerge(1) converts between
character sets.

This switch does also apply to chapters that are copied from
certain container types, e.g. Ogg/OGM and MP4 files. See the
section about chapters below for details.

--cue-chapter-name-format format
mkvmerge(1) supports reading CUE sheets for audio files as the
input for chapters. CUE sheets usually contain the entries
PERFORMER and TITLE for each index entry. mkvmerge(1) uses these
two strings in order to construct the chapter name. With this
option the format used for this name can be set.

If this option is not given then mkvmerge(1) defaults to the format
'%p - %t' (the performer, followed by a space, a dash, another
space and the title).

If the format is given then everything except the following meta
characters is copied as-is, and the meta characters are replaced
like this:

o %p is replaced by the current entry's PERFORMER string,

o %t is replaced by the current entry's TITLE string,

o %n is replaced by the current track number and

o %N is replaced by the current track number padded with a
leading zero if it is < 10.

--chapters file-name
Read chapter information from the file file-name. See the section
about chapters below for details.

--global-tags file-name
Read global tags from the file file-name. See the section about
tags below for details.

General output control (advanced global options)
--track-order FID1:TID1,FID2:TID2,...
This option changes the order in which the tracks for an input file
are created. The argument is a comma separated list of pairs IDs.
Each pair contains first the file ID (FID1) which is simply the
number of the file on the command line starting at 0. The second is
a track ID (TID1) from that file. If some track IDs are omitted
then those tracks are created after the ones given with this option
have been created.

--cluster-length spec
Limit the number of data blocks or the duration of data in each
cluster. The spec parameter can either be a number n without a unit
or a number d postfixed with 'ms'.

If no unit is used then mkvmerge(1) will put at most n data blocks
into each cluster. The maximum number of blocks is 65535.

If the number d is postfixed with 'ms' then mkvmerge(1) puts at
most d milliseconds of data into each cluster. The minimum for d is
'100ms', and the maximum is '32000ms'.

mkvmerge(1) defaults to putting at most 65535 data blocks and
5000ms of data into a cluster.

Programs trying to find a certain frame can only seek directly to a
cluster and have to read the whole cluster afterwards. Therefore
creating larger clusters may lead to imprecise or slow seeking.

--no-cues
Tells mkvmerge(1) not to create and write the cue data which can be
compared to an index in an AVI. Matroska(TM) files can be played
back without the cue data, but seeking will probably be imprecise
and slower. Use this only if you're really desperate for space or
for testing purposes. See also option --cues which can be specified
for each input file.

--clusters-in-meta-seek
Tells mkvmerge(1) to create a meta seek element at the end of the
file containing all clusters. See also the section about the
Matroska(TM) file layout.

--disable-lacing
Disables lacing for all tracks. This will increase the file's size,
especially if there are many audio tracks. This option is not
intended for everyday use.

--enable-durations
Write durations for all blocks. This will increase file size and
does not offer any additional value for players at the moment.

--disable-track-statistics-tags
Normally mkvmerge(1) will write certain tags with statistics for
each track. If such tags are already present then they will be
overwritten. The tags are BPS, DURATION, NUMBER_OF_BYTES and
NUMBER_OF_FRAMES.

Enabling this option prevents mkvmerge(1) from writing those tags
and from touching any existing tags with same names.

--timecode-scale factor
Forces the timecode scale factor to factor. Valid values are in the
range 1000..10000000 or the special value -1.

Normally mkvmerge(1) will use a value of 1000000 which means that
timecodes and durations will have a precision of 1ms. For files
that will not contain a video track but at least one audio track
mkvmerge(1) will automatically chose a timecode scale factor so
that all timecodes and durations have a precision of one audio
sample. This causes bigger overhead but allows precise seeking and
extraction.

If the special value -1 is used then mkvmerge(1) will use sample
precision even if a video track is present.

File splitting, linking, appending and concatenation (more global options)
--split specification
Splits the output file after a given size or a given time. Please
note that tracks can only be split right before a key frame. Due to
buffering mkvmerge(1) will split right before the next key frame
after the split point has been reached. Therefore the split point
may be a bit off from what the user has specified.

At the moment mkvmerge(1) supports four different modes.

1. Splitting by size.

Syntax: --split[size:]d[k|m|g]

Examples: --split size:700m or --split 150000000

The parameter d may end with 'k', 'm' or 'g' to indicate that
the size is in KB, MB or GB respectively. Otherwise a size in
bytes is assumed. After the current output file has reached
this size limit a new one will be started.

The 'size:' prefix may be omitted for compatibility reasons.

2. Splitting after a duration.

Syntax: --split[duration:]HH:MM:SS.nnnnnnnnn|ds

Examples: --split duration:00:60:00.000 or --split 3600s

The parameter must either have the form HH:MM:SS.nnnnnnnnn for
specifying the duration in up to nano-second precision or be a
number d followed by the letter 's' for the duration in
seconds. HH is the number of hours, MM the number of minutes,
SS the number of seconds and nnnnnnnnn the number of
nanoseconds. Both the number of hours and the number of
nanoseconds can be omitted. There can be up to nine digits
after the decimal point. After the duration of the contents in
the current output has reached this limit a new output file
will be started.

The 'duration:' prefix may be omitted for compatibility
reasons.

3. Splitting after specific timecodes.

Syntax: --splittimecodes:A[,B[,C...]]

Example: --split timecodes:00:45:00.000,01:20:00.250,6300s

The parameters A, B, C etc must all have the same format as the
ones used for the duration (see above). The list of timecodes
is separated by commas. After the input stream has reached the
current split point's timecode a new file is created. Then the
next split point given in this list is used.

The 'timecodes:' prefix must not be omitted.

4. Keeping specific parts by specifying timecode ranges while
discarding others.

Syntax:
--splitparts:start1-end1[,[+]start2-end2[,[+]start3-end3...]]

Examples:

1. --split parts:00:01:20-00:02:45,00:05:50-00:10:30

2. --split parts:00:01:20-00:02:45,+00:05:50-00:10:30

3. --split parts:-00:02:45,00:05:50-

The parts mode tells mkvmerge(1) to keep certain ranges of
timecodes while discarding others. The ranges to keep have to
be listed after the parts: keyword and be separated by commas.
A range itself consists of a start and an end timecode in the
same format the other variations of --split accept (e.g. both
00:01:20 and 80s refer to the same timecode).

If a start timecode is left out then it defaults to the
previous range's end timecode. If there was no previous range
then it defaults to the start of the file (see example 3).

If an end timecode is left out then it defaults to the end of
the source files which basically tells mkvmerge(1) to keep the
rest (see example 3).

Normally each range will be written to a new file. This can be
changed so that consecutive ranges are written to the same
file. For that the user has to prefix the start timecode with a
+. This tells mkvmerge(1) not to create a new file and instead
append the range to the same file the previous range was
written to. Timecodes will be adjusted so that there will be no
gap in the output file even if there was a gap in the two
ranges in the input file.

In example 1 mkvmerge(1) will create two files. The first will
contain the content starting from 00:01:20 until 00:02:45. The
second file will contain the content starting from 00:05:50
until 00:10:30.

In example 2 mkvmerge(1) will create only one file. This file
will contain both the content starting from 00:01:20 until
00:02:45 and the content starting from 00:05:50 until 00:10:30.

In example 3 mkvmerge(1) will create two files. The first will
contain the content from the start of the source files until
00:02:45. The second file will contain the content starting
from 00:05:50 until the end of the source files.

Note
Note that mkvmerge(1) only makes decisions about splitting
at key frame positions. This applies to both the start and
the end of each range. So even if an end timecode is
between two key frames mkvmerge(1) will continue outputting
the frames up to but excluding the following key frame.

5. Keeping specific parts by specifying frame/field number ranges
while discarding others.

Syntax:
--splitparts-frames:start1-end1[,[+]start2-end2[,[+]start3-end3...]]

Examples:

1. --split parts-frames:137-258,548-1211

2. --split parts-frames:733-912,+1592-2730

3. --split parts-frames:-430,2512-

The parts-frames mode tells mkvmerge(1) to keep certain ranges
of frame/field numbers while discarding others. The ranges to
keep have to be listed after the parts-frames: keyword and be
separated by commas. A range itself consists of a start and an
end frame/field number. Numbering starts at 1.

If a start number is left out then it defaults to the previous
range's end number. If there was no previous range then it
defaults to the start of the file (see example 3).

If an end number is left out then it defaults to the end of the
source files which basically tells mkvmerge(1) to keep the rest
(see example 3).

Normally each range will be written to a new file. This can be
changed so that consecutive ranges are written to the same
file. For that the user has to prefix the start number with a
+. This tells mkvmerge(1) not to create a new file and instead
append the range to the same file the previous range was
written to. Timecodes will be adjusted so that there will be no
gap in the output file even if there was a gap in the two
ranges in the input file.

Note
Note that mkvmerge(1) only makes decisions about splitting
at key frame positions. This applies to both the start and
the end of each range. So even if an end frame/field number
is between two key frames mkvmerge(1) will continue
outputting the frames up to but excluding the following key
frame.
In example 1 mkvmerge(1) will create two files. The first will
contain the content starting from the first key frame at or
after 137 up to but excluding the first key frame at or after
258. The second file will contain the content starting from 548
until 1211.

In example 2 mkvmerge(1) will create only one file. This file
will contain both the content starting from 733 until 912 and
the content starting from 1592 until 2730.

In example 3 mkvmerge(1) will create two files. The first will
contain the content from the start of the source files until
430. The second file will contain the content starting from
2512 until the end of the source files.

This mode considers only the first video track that is output.
If no video track is output no splitting will occur.

Note
The numbers given with this argument are interpreted based
on the number of Matroska(TM) blocks that are output. A
single Matroska(TM) block contains either a full frame (for
progressive content) or a single field (for interlaced
content). mkvmerge does not distinguish between those two
and simply counts the number of blocks. For example: If one
wanted to split after the 25th full frame with interlaced
content one would have to use 50 (two fields per full
frame) as the split point.

6. Splitting after specific frames/fields.

Syntax: --splitframes:A[,B[,C...]]

Example: --split frames:120,237,891

The parameters A, B, C etc must all be positive integers.
Numbering starts at 1. The list of frame/field numbers is
separated by commas. After the input stream has reached the
current split point's frame/field number a new file is created.
Then the next split point given in this list is used.

The 'frames:' prefix must not be omitted.

This mode considers only the first video track that is output.
If no video track is output no splitting will occur.

7. Splitting before specific chapters.

Syntax: --splitchapters:all or --splitchapters:A[,B[,C...]]

Example: --split chapters:5,8

The parameters A, B, C etc must all be positive integers.
Numbering starts at 1. The list of chapter numbers is separated
by commas. Splitting will occur right before the first key
frame whose timecode is equal to or bigger than the start
timecode for the chapters whose numbers are listed. A chapter
starting at 0s is never considered for splitting and discarded
silently.

The keyword all can be used instead of listing all chapter
numbers manually.

The 'chapters:' prefix must not be omitted.

Note
The Matroska(TM) file format supports arbitrary deeply
nested chapter structures called 'edition entries' and
'chapter atoms'. However, this mode only considers the
top-most level of chapters across all edition entries.

For this splitting mode the output filename is treated differently
than for the normal operation. It may contain a printf like
expression '%d' including an optional field width, e.g. '%02d'. If
it does then the current file number will be formatted
appropriately and inserted at that point in the filename. If there
is no such pattern then a pattern of '-%03d' is assumed right
before the file's extension: '-o output.mkv' would result in
'output-001.mkv' and so on. If there's no extension then '-%03d'
will be appended to the name.

--link
Link files to one another when splitting the output file. See the
section on file linking below for details.

--link-to-previous segment-UID
Links the first output file to the segment with the segment UID
given by the segment-UID parameter. See the section on file linking
below for details.

If SID starts with = then its rest is interpreted as the name of a
Matroska file whose segment UID is read and used.

--link-to-next segment-UID
Links the last output file to the segment with the segment UID
given by the segment-UID parameter. See the section on file linking
below for details.

If SID starts with = then its rest is interpreted as the name of a
Matroska file whose segment UID is read and used.

--append-mode mode
Determines how timecodes are calculated when appending files. The
parameter mode can have two values: 'file' which is also the
default and 'track'.

When mkvmerge appends a track (called 'track2_1' from now on) from
a second file (called 'file2') to a track (called 'track1_1') from
the first file (called 'file1') then it has to offset all timecodes
for 'track2_1' by an amount. For 'file' mode this amount is the
highest timecode encountered in 'file1' even if that timecode was
from a different track than 'track1_1'. In track mode the offset is
the highest timecode of 'track1_1'.

Unfortunately mkvmerge cannot detect which mode to use reliably.
Therefore it defaults to 'file' mode. 'file' mode usually works
better for files that have been created independently of each
other; e.g. when appending AVI or MP4 files. 'track' mode may work
better for sources that are essentially just parts of one big file,
e.g. for VOB and EVO files.

Subtitle tracks are always treated as if 'file' mode were active
even if 'track' mode actually is.

--append-to SFID1:STID1:DFID1:DTID1[,...]
This option controls to which track another track is appended. Each
spec contains four IDs: a file ID, a track ID, a second file ID and
a second track ID. The first pair, "source file ID" and "source
track ID", identifies the track that is to be appended. The second
pair, "destination file ID" and "destination track ID", identifies
the track the first one is appended to.

If this option has been omitted then a standard mapping is used.
This standard mapping appends each track from the current file to a
track from the previous file with the same track ID. This allows
for easy appending if a movie has been split into two parts and
both file have the same number of tracks and track IDs with the
command mkvmerge -o output.mkv part1.mkv +part2.mkv.

*
A single '+' causes the next file to be appended instead of added.
The '+' can also be put in front of the next file name. Therefore
the following two commands are equivalent:

$ mkvmerge -o full.mkv file1.mkv + file2.mkv
$ mkvmerge -o full.mkv file1.mkv +file2.mkv

=
Normally mkvmerge(1) looks for files in the same directory as an
input file that have the same base name and only differ in their
running number (e.g. 'VTS_01_1.VOB', 'VTS_01_2.VOB', 'VTS_01_3.VOB'
etc) and treats all of those files as if they were concatenated
into a single big file. This option, a single '=', causes mkvmerge
not to look for those additional files.

The '=' can also be put in front of the next file name. Therefore
the following two commands are equivalent:

$ mkvmerge -o full.mkv = file1.mkv
$ mkvmerge -o full.mkv =file1.mkv

( file1 file2 )
If multiple file names are contained in a pair of parenthesis then
those files will be treated as if they were concatenated into a
single big file consisting of the content of each of the files one
after the other.

This can be used for e.g. VOB files coming from a DVD or MPEG
transport streams. It cannot be used if each file contains its own
set of headers which is usually the case with stand-alone files
like AVI or MP4.

Putting a file name into parenthesis also prevents mkvmerge(1) from
looking for additional files with the same base name as described
in option =. Therefore these two command lines are equivalent:

$ mkvmerge -o out.mkv = file.mkv
$ mkvmerge -o out.mkv '(' file.mkv ')'

Several things should be noted:

1. There must be spaces both after the opening and before the
closing parenthesis.

2. Every parameter between parenthesis is interpreted as a file
name. Therefore all options applying to this logical file must
be listed before the opening parenthesis.

3. Some shells treat parenthesis as special characters. Hence you
must escape or quote them as shown in the example above.

Attachment support (more global options)
--attachment-description description
Plain text description of the following attachment. Applies to the
next --attach-file or --attach-file-once option.

--attachment-mime-type MIME type
MIME type of the following attachment. Applies to the next
--attach-file or --attach-file-once option. A list of officially
recognized MIME types can be found e.g. at the IANA homepage[2].
The MIME type is mandatory for an attachment.

--attachment-name name
Sets the name that will be stored in the output file for this
attachment. If this option is not given then the name will be
derived from the file name of the attachment as given with the
--attach-file or the --attach-file-once option.

--attach-file file-name, --attach-file-once file-name
Creates a file attachment inside the Matroska(TM) file. The MIME
type must have been set before this option can used. The difference
between the two forms is that during splitting the files attached
with --attach-file are attached to all output files while the ones
attached with --attach-file-once are only attached to the first
file created. If splitting is not used then both do the same.

mkvextract(1) can be used to extract attached files from a
Matroska(TM) file.

Options that can be used for each input file
-a, --audio-tracks [!]n,m,...
Copy the audio tracks n, m etc. The numbers are track IDs which can
be obtained with the --identify switch. They're not simply the
track numbers (see section track IDs). Default: copy all audio
tracks.

Instead of track IDs you can also provide ISO 639-2 language codes.
This will only work for source files that provide language tags for
their tracks.

Default: copy all tracks of this kind.

If the IDs are prefixed with ! then the meaning is reversed: copy
all tracks of this kind but the ones listed after the !.

-d, --video-tracks [!]n,m,...
Copy the video tracks n, m etc. The numbers are track IDs which can
be obtained with the --identify switch. They're not simply the
track numbers (see section track IDs). Default: copy all video
tracks.

Instead of track IDs you can also provide ISO 639-2 language codes.
This will only work for source files that provide language tags for
their tracks.

If the IDs are prefixed with ! then the meaning is reversed: copy
all tracks of this kind but the ones listed after the !.

-s, --subtitle-tracks [!]n,m,...
Copy the subtitle tracks n, m etc. The numbers are track IDs which
can be obtained with the --identify switch. They're not simply the
track numbers (see section track IDs). Default: copy all subtitle
tracks.

Instead of track IDs you can also provide ISO 639-2 language codes.
This will only work for source files that provide language tags for
their tracks.

If the IDs are prefixed with ! then the meaning is reversed: copy
all tracks of this kind but the ones listed after the !.

-b, --button-tracks [!]n,m,...
Copy the button tracks n, m etc. The numbers are track IDs which
can be obtained with the --identify switch. They're not simply the
track numbers (see section track IDs). Default: copy all button
tracks.

Instead of track IDs you can also provide ISO 639-2 language codes.
This will only work for source files that provide language tags for
their tracks.

If the IDs are prefixed with ! then the meaning is reversed: copy
all tracks of this kind but the ones listed after the !.

--track-tags [!]n,m,...
Copy the tags for tracks n, m etc. The numbers are track IDs which
can be obtained with the --identify switch (see section track IDs).
They're not simply the track numbers. Default: copy tags for all
tracks.

If the IDs are prefixed with ! then the meaning is reversed: copy
everything but the IDs listed after the !.

-m, --attachments [!]n[:all|first],m[:all|first],...
Copy the attachments with the IDs n, m etc to all or only the first
output file. Each ID can be followed by either ':all' (which is the
default if neither is entered) or ':first'. If splitting is active
then those attachments whose IDs are specified with ':all' are
copied to all of the resulting output files while the others are
only copied into the first output file. If splitting is not active
then both variants have the same effect.

The default is to copy all attachments to all output files.

If the IDs are prefixed with ! then the meaning is reversed: copy
everything but the IDs listed after the !.

-A, --no-audio
Don't copy any audio track from this file.

-D, --no-video
Don't copy any video track from this file.

-S, --no-subtitles
Don't copy any subtitle track from this file.

-B, --no-buttons
Don't copy any button track from this file.

-T, --no-track-tags
Don't copy any track specific tags from this file.

--no-chapters
Don't copy chapters from this file.

-M, --no-attachments
Don't copy attachments from this file.

--no-global-tags
Don't copy global tags from this file.

--chapter-charset character-set
Sets the charset that is used for the conversion to UTF-8 for
chapter information contained in the source file. See the section
about text files and character sets for an explanation how
mkvmerge(1) converts between character sets.

--chapter-language language-code
Sets the ISO639-2 language code that is written for each chapter
entry. This option can be used for source files that contain
chapters but no information about the chapters' languages, e.g. for
MP4 and OGM files.

-y, --sync TID:d[,o[/p]]
Adjust the timecodes of the track with the id TID by d ms. The
track IDs are the same as the ones given with --identify (see
section track IDs).

o/p: adjust the timestamps by o/p to fix linear drifts. p defaults
to 1 if omitted. Both o and p can be floating point numbers.

Defaults: no manual sync correction (which is the same as d = 0 and
o/p = 1.0).

This option can be used multiple times for an input file applying
to several tracks by selecting different track IDs each time.

--cues TID:none|iframes|all
Controls for which tracks cue (index) entries are created for the
given track (see section track IDs). 'none' inhibits the creation
of cue entries. For 'iframes' only blocks with no backward or
forward references ( = I frames in video tracks) are put into the
cue sheet. 'all' causes mkvmerge(1) to create cue entries for all
blocks which will make the file very big.

The default is 'iframes' for video tracks and 'none' for all
others. See also option --no-cues which inhibits the creation of
cue entries regardless of the --cues options used.

This option can be used multiple times for an input file applying
to several tracks by selecting different track IDs each time.

--default-track TID[:bool]
Sets the 'default' flag for the given track (see section track IDs)
if the optional argument bool is not present. If the user does not
explicitly select a track himself then the player should prefer the
track that has his 'default' flag set. Only one track of each kind
(audio, video, subtitles, buttons) can have his 'default' flag set.
If the user wants no track to have the default track flag set then
he has to set bool to 0 for all tracks.

This option can be used multiple times for an input file applying
to several tracks by selecting different track IDs each time.

--forced-track TID[:bool]
Sets the 'forced' flag for the given track (see section track IDs)
if the optional argument bool is not present. A player must play
all tracks for which this flag is set to 1.

This option can be used multiple times for an input file applying
to several tracks by selecting different track IDs each time.

--blockadd TID:level
Keep only the BlockAdditions up to the level level for the given
track. The default is to keep all levels. This option only affects
certain kinds of codecs like WAVPACK4.

--track-name TID:name
Sets the track name for the given track (see section track IDs) to
name.

--language TID:language
Sets the language for the given track (see section track IDs). Both
ISO639-2 language codes and ISO639-1 country codes are allowed. The
country codes will be converted to language codes automatically.
All languages including their ISO639-2 codes can be listed with the
--list-languages option.

This option can be used multiple times for an input file applying
to several tracks by selecting different track IDs each time.

-t, --tags TID:file-name
Read tags for the track with the number TID from the file
file-name. See the section about tags below for details.

--aac-is-sbr TID[:0|1]
Tells mkvmerge(1) that the track with the ID TID is SBR AAC (also
known as HE-AAC or AAC+). This options is needed if a) the source
file is an AAC file (not for a Matroska(TM) file) and b) the AAC
file contains SBR AAC data. The reason for this switch is that it
is technically impossible to automatically tell normal AAC data
from SBR AAC data without decoding a complete AAC frame. As there
are several patent issues with AAC decoders mkvmerge(1) will never
contain this decoding stage. So for SBR AAC files this switch is
mandatory. The resulting file might not play back correctly or even
not at all if the switch was omitted.

If the source file is a Matroska(TM) file then the CodecID should
be enough to detect SBR AAC. However, if the CodecID is wrong then
this switch can be used to correct that.

If mkvmerge wrongfully detects that an AAC file is SBR then you can
add ':0' to the track ID.

--reduce-to-core TID
Some audio codecs have a lossy core and optional extensions that
implement lossless decoding. This option tells mkvmerge(1) to only
copy the core but not the extensions. By default mkvmerge(1) copies
both the core and the extensions.

Currently only DTS tracks are affected by this option. TrueHD
tracks that contain an embedded AC-3 core are instead presented as
two separate tracks for which the user can select which track to
copy. For DTS such a scheme would not work as the HD extensions
cannot be decoded by themselves - unlike the TrueHD data.

If mkvmerge wrongfully detects that an AAC file is SBR then you can
add ':0' to the track ID.

--timecodes TID:file-name
Read the timecodes to be used for the specific track ID from
file-name. These timecodes forcefully override the timecodes that
mkvmerge(1) normally calculates. Read the section about external
timecode files.

--default-duration TID:x
Forces the default duration of a given track to the specified
value. Also modifies the track's timecodes to match the default
duration. The argument x must be postfixed with 's', 'ms', 'us',
'ns', 'fps', 'p' or 'i' to specify the default duration in seconds,
milliseconds, microseconds, nanoseconds, 'frames per second',
'progressive frames per second' or 'interlaced frames per second'
respectively. The number x itself can be a floating point number or
a fraction.

If the default duration is not forced then mkvmerge will try to
derive the track's default duration from the container and/or the
encoded bitstream for certain track types, e.g. AVC/h.264 or
MPEG-2.

This option can also be used to change the FPS of video tracks
without having to use an external timecode file.

--fix-bitstream-timing-information TID[:0|1]
Normally mkvmerge(1) does not change the timing information
(frame/field rate) stored in the video bitstream. With this option
that information is adjusted to match the container timing
information. The container timing information can come from various
sources: from the command line (see option --default-duration), the
source container or derived from the bitstream.

Note
This has only been implemented for AVC/h.264 video tracks so
far.

--nalu-size-length TID:n
Forces the NALU size length to n bytes. This parameter is only used
if the AVC/h.264 elementary stream packetizer is used. If left out
it defaults to 4 bytes, but there are files that contain frames or
slices that are all smaller than 65536 bytes. For such files you
can use this parameter and decrease the size to 2.

--compression TID:n
Selects the compression method to be used for the track. Note that
the player also has to support this method. Valid values are
'none', 'zlib', 'lzo'/'lxo1x', 'bz2'/'bzlib' and
'mpeg4_p2'/'mpeg4p2'. The values 'lzo'/'lxo1x' and 'bz2'/'bzlib'
are only available if mkvmerge(1) has been compiled with support
for the liblzo(TM) and bzlib(TM) compression libraries,
respectively.

The compression method 'mpeg4_p2'/'mpeg4p2' is a special
compression method called 'header removal' that is only available
for MPEG4 part 2 video tracks.

The default for some subtitle tracks is 'zlib' compression. This
compression method is also the one that most if not all playback
applications support. Support for other compression methods other
than 'none' is not assured.

Options that only apply to video tracks
-f, --fourcc TID:FourCC
Forces the FourCC to the specified value. Works only for video
tracks in the 'MS compatibility mode'.

--display-dimensions TID:widthxheight
Matroska(TM) files contain two values that set the display
properties that a player should scale the image on playback to:
display width and display height. These values can be set with this
option, e.g. '1:640x480'.

Another way to specify the values is to use the --aspect-ratio or
the --aspect-ratio-factor option (see below). These options are
mutually exclusive.

--aspect-ratio TID:ratio|width/height
Matroska(TM) files contain two values that set the display
properties that a player should scale the image on playback to:
display width and display height. With this option mkvmerge(1) will
automatically calculate the display width and display height based
on the image's original width and height and the aspect ratio given
with this option. The ratio can be given either as a floating point
number ratio or as a fraction 'width/height', e.g. '16/9'.

Another way to specify the values is to use the
--aspect-ratio-factor or --display-dimensions options (see above
and below). These options are mutually exclusive.

--aspect-ratio-factor TID:factor|n/d
Another way to set the aspect ratio is to specify a factor. The
original aspect ratio is first multiplied with this factor and used
as the target aspect ratio afterwards.

Another way to specify the values is to use the --aspect-ratio or
--display-dimensions options (see above). These options are
mutually exclusive.

--cropping TID:left,top,right,bottom
Sets the pixel cropping parameters of a video track to the given
values.

--stereo-mode TID:n|keyword
Sets the stereo mode for the video track with the track ID TID. The
mode can either be a number n between 0 and 14 or one of these
keywords:

'mono', 'side_by_side_left_first', 'top_bottom_right_first',
'top_bottom_left_first', 'checkerboard_right_first',
'checkerboard_left_first', 'row_interleaved_right_first',
'row_interleaved_left_first', 'column_interleaved_right_first',
'column_interleaved_left_first', 'anaglyph_cyan_red',
'side_by_side_right_first', 'anaglyph_green_magenta',
'both_eyes_laced_left_first', 'both_eyes_laced_right_first'.

Options that only apply to text subtitle tracks
--sub-charset TID:character-set
Sets the character set for the conversion to UTF-8 for UTF-8
subtitles for the given track ID. If not specified the charset will
be derived from the current locale settings. Note that a charset is
not needed for subtitles read from Matroska(TM) files or from Kate
streams, as these are always stored in UTF-8. See the section about
text files and character sets for an explanation how mkvmerge(1)
converts between character sets.

This option can be used multiple times for an input file applying
to several tracks by selecting different track IDs each time.

Other options
-i, --identify file-name
Will let mkvmerge(1) probe the single file and report its type, the
tracks contained in the file and their track IDs. If this option is
used then the only other option allowed is the filename.

The output format used for the result can be changed with the
option --identification-format.

-I, --identify-verbose file-name
This option is deprecated. Use --identification-format verbose-text
--identify ... instead.

-F, --identification-format format
Determines the output format used by the --identify option. The
following formats are supported: text (the default if this option
isn't used), verbose-text and json.

1. The text format is short and human-readable. It consists of one
line per item found (container, tracks, attachments etc.).

This format is not meant to be parsed. The output will be
translated into the language mkvmerge(1) uses (see also --ui-
language).

2. The verbose-text format extends the text format with additional
properties for each item. The extra information is surronded by
square brackets. It consists of space-saparated key/value pairs
where keys and values are separated by a colon.

Each value is escaped according to the rules described in the
section about escaping special characters in text.

This format is not meant to be parsed. The output will be
translated into the language mkvmerge(1) uses (see also --ui-
language).

3. The json format outputs a machine-readable JSON representation.
This format follows the JSON schema described in the file
mkvmerge-identification-output-schema.json[3].

-l, --list-types
Lists supported input file types.

--list-languages
Lists all languages and their ISO639-2 code which can be used with
the --language option.

--priority priority
Sets the process priority that mkvmerge(1) runs with. Valid values
are 'lowest', 'lower', 'normal', 'higher' and 'highest'. If nothing
is given then 'normal' is used. On Unix like systems mkvmerge(1)
will use the nice(2) function. Therefore only the super user can
use 'higher' and 'highest'. On Windows all values are useable for
every user.

Selecting 'lowest' also causes mkvmerge(1) to select idle I/O
priority in addition to the lowest possible process priority.

--command-line-charset character-set
Sets the character set to convert strings given on the command line
from. It defaults to the character set given by system's current
locale. This settings applies to arguments of the following
options: --title, --track-name and --attachment-description.

--output-charset character-set
Sets the character set to which strings are converted that are to
be output. It defaults to the character set given by system's
current locale.

-r, --redirect-output file-name
Writes all messages to the file file-name instead of to the
console. While this can be done easily with output redirection
there are cases in which this option is needed: when the terminal
reinterprets the output before writing it to a file. The character
set set with --output-charset is honored.

--ui-language code
Forces the translations for the language code to be used (e.g.
'de_DE' for the German translations). It is preferable to use the
environment variables LANG, LC_MESSAGES and LC_ALL though. Entering
'list' as the code will cause mkvmerge(1) to output a list of
available translations.

--debug topic
Turn on debugging for a specific feature. This option is only
useful for developers.

--engage feature
Turn on experimental features. A list of available features can be
requested with mkvmerge --engage list. These features are not meant
to be used in normal situations.

--gui-mode
Turns on GUI mode. In this mode specially-formatted lines may be
output that can tell a controlling GUI what's happening. These
messages follow the format '#GUI#message'. The message may be
followed by key/value pairs as in
'#GUI#message#key1=value1#key2=value2...'. Neither the messages nor
the keys are ever translated and always output in English.

@options-file
Reads additional command line arguments from the file options-file.
See the section about option files for further information.

--capabilities
Lists information about optional features that have been compiled
in and exit. The first line output will be the version information.
All following lines contain exactly one word whose presence
indicates that the feature has been compiled in. These features
are:

o 'BZ2' -- the bzlib(TM) compression library. Affects the
available compression methods for the --compression option.

o 'LZO' -- the lzo(TM) compression library. Affects the available
compression methods for the --compression option.

o 'FLAC' -- reading raw FLAC files and handling FLAC tracks in
other containers, e.g. Ogg(TM) or Matroska(TM).

-h, --help
Show usage information and exit.

-V, --version
Show version information and exit.

--check-for-updates
Checks online for new releases by downloading the URL
http://mkvtoolnix-releases.bunkus.org/latest-release.xml. Four
lines will be output in key=value style: the URL from where the
information was retrieved (key version_check_url), the currently
running version (key running_version), the latest release's version
(key available_version) and the download URL (key download_url).

Afterwards the program exists with an exit code of 0 if no newer
release is available, with 1 if a newer release is available and
with 2 if an error occured (e.g. if the update information could
not be retrieved).

This option is only available if the program was built with support
for libcurl.

USAGE
For each file the user can select which tracks mkvmerge(1) should take.
They are all put into the file specified with -o. A list of known (and
supported) source formats can be obtained with the -l option.

Important

The order of command line options is important. Please read the
section "Option order" if you're new to the program.

OPTION ORDER
The order in which options are entered is important for some options.
Options fall into two categories:

1. Options that affect the whole program and are not tied to any input
file. These include but are not limited to --command-line-charset,
--output or --title. These can appear anywhere on the command line.

2. Options that affect a single input file or a single track in an
input file. These options all apply to the following input file on
the command line. All options applying to the same input (or to
tracks from the same input file) file can be written in any order
as long as they all appear before that input file's name. Examples
for options applying to an input file are --no-chapters or
--chapter-charset. Examples for options applying to a single track
are --default-duration or --language.

The options are processed from left to right. If an option appears
multiple times within the same scope then the last occurence will be
used. Therefore the title will be set to "Something else" in the
following example:

$ mkvmerge -o output.mkv --title 'This and that' input.avi --title 'Something else'

The following example shows that using the --language option twice is
OK because they're used in different scopes. Even though they apply to
the same track ID they apply to different input files and therefore
have different scopes:

$ mkvmerge -o output.mkv --language 0:fre francais.ogg --language 0:deu deutsch.ogg

EXAMPLES
Let's assume you have a file called MyMovie.avi and the audio track in
a separate file, e.g. 'MyMovie.wav'. First you want to encode the audio
to OggVorbis(TM):

$ oggenc -q4 -oMyMovie.ogg MyMovie.wav

After a couple of minutes you can join video and audio:

$ mkvmerge -o MyMovie-with-sound.mkv MyMovie.avi MyMovie.ogg

If your AVI already contains an audio track then it will be copied as
well (if mkvmerge(1) supports the audio format). To avoid that simply
do

$ mkvmerge -o MyMovie-with-sound.mkv -A MyMovie.avi MyMovie.ogg

After some minutes of consideration you rip another audio track, e.g.
the director's comments or another language to 'MyMovie-add-audio.wav'.
Encode it again and join it up with the other file:

$ oggenc -q4 -oMyMovie-add-audio.ogg MyMovie-add-audio.wav
$ mkvmerge -o MM-complete.mkv MyMovie-with-sound.mkv MyMovie-add-audio.ogg

The same result can be achieved with

$ mkvmerge -o MM-complete.mkv -A MyMovie.avi MyMovie.ogg MyMovie-add-audio.ogg

Now fire up mplayer(TM) and enjoy. If you have multiple audio tracks
(or even video tracks) then you can tell mplayer(TM) which track to
play with the '-vid' and '-aid' options. These are 0-based and do not
distinguish between video and audio.

If you need an audio track synchronized you can do that easily. First
find out which track ID the Vorbis track has with

$ mkvmerge --identify outofsync.ogg

Now you can use that ID in the following command line:

$ mkvmerge -o goodsync.mkv -A source.avi -y 12345:200 outofsync.ogg

This would add 200ms of silence at the beginning of the audio track
with the ID 12345 taken from 'outofsync.ogg'.

Some movies start synced correctly but slowly drift out of sync. For
these kind of movies you can specify a delay factor that is applied to
all timestamps -- no data is added or removed. So if you make that
factor too big or too small you'll get bad results. An example is that
an episode I transcoded was 0.2 seconds out of sync at the end of the
movie which was 77340 frames long. At 29.97fps0.2 seconds correspond to
approx. 6 frames. So I did

$ mkvmerge -o goodsync.mkv -y 23456:0,77346/77340 outofsync.mkv

The result was fine.

The sync options can also be used for subtitles in the same manner.

For text subtitles you can either use some Windows software (like
SubRipper(TM)) or the subrip(TM) package found in transcode(1)'s
sources in the 'contrib/subrip' directory. The general process is:

1. extract a raw subtitle stream from the source:

$ tccat -i /path/to/copied/dvd/ -T 1 -L | tcextract -x ps1 -t vob -a 0x20 | subtitle2pgm -o mymovie

2. convert the resulting PGM images to text with gocr:

$ pgm2txt mymovie

3. spell-check the resulting text files:

$ ispell -d american *txt

4. convert the text files to a SRT file:

$ srttool -s -w -i mymovie.srtx -o mymovie.srt

The resulting file can be used as another input file for mkvmerge(1):

$ mkvmerge -o mymovie.mkv mymovie.avi mymovie.srt

If you want to specify the language for a given track then this is
easily done. First find out the ISO639-2 code for your language.
mkvmerge(1) can list all of those codes for you:

$ mkvmerge --list-languages

Search the list for the languages you need. Let's assume you have put
two audio tracks into a Matroska(TM) file and want to set their
language codes and that their track IDs are 2 and 3. This can be done
with

$ mkvmerge -o with-lang-codes.mkv --language 2:ger --language 3:dut without-lang-codes.mkv

As you can see you can use the --language switch multiple times.

Maybe you'd also like to have the player use the Dutch language as the
default language. You also have extra subtitles, e.g. in English and
French, and want to have the player display the French ones by default.
This can be done with

$ mkvmerge -o with-lang-codes.mkv --language 2:ger --language 3:dut --default-track 3 without-lang-codes.mkv --language 0:eng english.srt --default-track 0 --language 0:fre french.srt

If you do not see the language or default track flags that you've
specified in mkvinfo(1)'s output then please read the section about
default values.

Turn off the compression for an input file.

$ mkvmerge -o no-compression.mkv --compression -1:none MyMovie.avi --compression -1:none mymovie.srt

TRACK IDS
Some of the options for mkvmerge(1) need a track ID to specify which
track they should be applied to. Those track IDs are printed by the
readers when demuxing the current input file, or if mkvmerge(1) is
called with the --identify option. An example for such output:

$ mkvmerge -i v.mkv
File 'v.mkv': container: Matroska(TM)
Track ID 0: video (V_MS/VFW/FOURCC, DIV3)
Track ID 1: audio (A_MPEG/L3)

Do not confuse the track IDs that are assigned to the tracks that are
placed in the output MKV file with the track IDs of the input files.
Only the input file track IDs are used for options needing these
values.

Also note that each input file has its own set of track IDs. Therefore
the track IDs for file 'file1.ext' as reported by 'mkvmerge --identify'
do not change no matter how many other input files are there or in
which position 'file1.ext' is used.

Track IDs are assigned like this:

o AVI files: The video track has the ID 0. The audio tracks get IDs
in ascending order starting at 1.

o AAC, AC-3, MP3, SRT and WAV files: The one 'track' in that file
gets the ID 0.

o Most other files: The track IDs are assigned in order the tracks
are found in the file starting at 0.

The special track ID '-1' is a wild card and applies the given switch
to all tracks that are read from an input file.

The options that use the track IDs are the ones whose description
contains 'TID'. The following options use track IDs as well:
--audio-tracks, --video-tracks, --subtitle-tracks, --button-tracks and
--track-tags.

TEXT FILES AND CHARACTER SET CONVERSIONS
Note

This section applies to all programs in MKVToolNix even if it only
mentions mkvmerge(1).

Introduction
All text in a Matroska(TM) file is encoded in UTF-8. This means that
mkvmerge(1) has to convert every text file it reads as well as every
text given on the command line from one character set into UTF-8. In
return this also means that mkvmerge(1)'s output has to be converted
back to that character set from UTF-8, e.g. if a non-English
translation is used with --ui-language or for text originating from a
Matroska(TM) file.

mkvmerge(1) does this conversion automatically based on the presence of
a byte order marker (short: BOM) or the system's current locale. How
the character set is inferred from the locale depends on the operating
system that mkvmerge(1) is run on.

Byte order markers (BOM)
Text files that start with a BOM are already encoded in one
representation of UTF. mkvmerge(1) supports the following five modes:
UTF-8, UTF-16 Little and Big Endian, UTF-32 Little and Big Endian. Text
files with a BOM are automatically converted to UTF-8. Any of the
parameters that would otherwise set the character set for such a file
(e.g. --sub-charset) is silently ignored.

Linux and Unix-like systems including Mac OS
On Unix-like systems mkvmerge(1) uses the setlocale(3) system call
which in turn uses the environment variables LANG, LC_ALL and LC_CYPE.
The resulting character set is often one of UTF-8 or the ISO-8859-*
family and is used for all text file operations and for encoding
strings on the command line and for output to the console.

Windows
On Windows the default character set used for converting text files is
determined by a call to the GetACP() system call.

Reading the command line is done with the GetCommandLineW() function
which already returns a Unicode string. Therefore the option
--command-line-charset is ignored on Windows.

Output to the console consists of three scenarios:

1. If the output is redirected with the option --redirect-output then
the default charset is UTF-8. This can be changed with
--output-charset.

If the output is redirected with cmd.exe itself, e.g. with mkvinfo
file.mkv > info.txt, then the charset is always UTF-8 and cannot be
changed.

Otherwise (when writing directly to the console) the Windows
function WriteConsoleW() is used and the option --output-charset is
ignored. The console should be able to output all Unicode
characters for which the corresponding language support is
installed (e.g. Chinese characters might not be displayed on
English Windows versions).

Command line options
The following options exist that allow specifying the character sets:

o --sub-charset for text subtitle files and for text subtitle tracks
stored in container formats for which the character set cannot be
determined unambiguously (e.g. Ogg files),

o --chapter-charset for chapter text files and for chapters and file
titles stored in container formats for which the character set
cannot be determined unambiguously (e.g. Ogg files for chapter
information, track and file titles etc; MP4 files for chapter
information),

o --command-line-charset for all strings on the command line,

o --output-charset for all strings written to the console or to a
file if the output has been redirected with the --redirect-output
option. On non-Windows systems the default for the output charset
is the system's current charset. On Windows it defaults to UTF-8
both for redirecting with --redirect-output and with cmd.exe
itself, e.g. mkvinfo file.mkv > info.txt.

OPTION FILES
An option file is a file mkvmerge(1) can read additional command line
arguments from. This can be used in order to circumvent certain
limitations of the shell or the operating system when executing
external programs like a limited command line length.

There are several rules regarding option files. Lines whose first
non-whitespace character is a hash mark ('#') are treated as comments
and ignored. White spaces at the start and end of a line will be
stripped. Each line must contain exactly one option.

A line not containing anything is also ignored. An empty argument is
represented by the line '#EMPTY#'.

Several chars can be escaped, e.g. if you need to start a non-comment
line with '#'. The rules are described in the section about escaping
text.

Note that backslashes must always be escaped. Hash marks ('#') must be
escaped if they should not start a comment.

The command line 'mkvmerge -o "my file.mkv" -A "a movie.avi" sound.ogg'
could be converted into the following option file:

# Write to the file "c:\Matroska\my file.mkv" on Windows.
-o
c:\\Matroska\\my file.mkv
# Set the title to '#65'.
--title
\h65
# Only take the video from "a movie.avi".
-A
a movie.avi
sound.ogg

ESCAPING SPECIAL CHARS IN TEXT
There are a few places in which special characters in text must or
should be escaped. The rules for escaping are simple: each character
that needs escaping is replaced with a backslash followed by another
character.

The rules are: ' ' (a space) becomes '\s', '"' (double quotes) becomes
'\2', ':' becomes '\c', '#' becomes '\h', '[' becomes '\b', ']' becomes
'\B' and '\' (a single backslash) itself becomes '\\'.

SUBTITLES
There are several text and bitmap subtitle formats that can be embedded
into Matroska(TM). Text subtitles must be recoded to UTF-8 so that they
can be displayed correctly by a player (see the section about text
files and character sets for an explanation how mkvmerge(1) converts
between character sets). Kate subtitles are already encoded in UTF-8
and do not have to be re-encoded.

The following subtitle formats are supported at the moment:

o Subtitle Ripper (SRT) files

o Substation Alpha (SSA) / Advanced Substation Alpha scripts (ASS)

o Universal Subtitle Format (USF) files

o OggKate streams

o VobSub bitmap subtitle files

o PGS bitmap subtitle files as found on BluRay discs

FILE LINKING
Matroska(TM) supports file linking which simply says that a specific
file is the predecessor or successor of the current file. To be
precise, it's not really the files that are linked but the Matroska(TM)
segments. As most files will probably only contain one Matroska(TM)
segment the following explanations use the term 'file linking' although
'segment linking' would be more appropriate.

Each segment is identified by a unique 128 bit wide segment UID. This
UID is automatically generated by mkvmerge(1). The linking is done
primarily via putting the segment UIDs (short: SID) of the
previous/next file into the segment header information. mkvinfo(1)
prints these SIDs if it finds them.

If a file is split into several smaller ones and linking is used then
the timecodes will not start at 0 again but will continue where the
last file has left off. This way the absolute time is kept even if the
previous files are not available (e.g. when streaming). If no linking
is used then the timecodes should start at 0 for each file. By default
mkvmerge(1) does not use file linking. If you want that you can turn it
on with the --link option. This option is only useful if splitting is
activated as well.

Regardless of whether splitting is active or not the user can tell
mkvmerge(1) to link the produced files to specific SIDs. This is
achieved with the options --link-to-previous and --link-to-next. These
options accept a segment SID in the format that mkvinfo(1) outputs: 16
hexadecimal numbers between 0x00 and 0xff prefixed with '0x' each, e.g.
'0x41 0xda 0x73 0x66 0xd9 0xcf 0xb2 0x1e 0xae 0x78 0xeb 0xb4 0x5e 0xca
0xb3 0x93'. Alternatively a shorter form can be used: 16 hexadecimal
numbers between 0x00 and 0xff without the '0x' prefixes and without the
spaces, e.g. '41da7366d9cfb21eae78ebb45ecab393'.

If splitting is used then the first file is linked to the SID given
with --link-to-previous and the last file is linked to the SID given
with --link-to-next. If splitting is not used then the one output file
will be linked to both of the two SIDs.

DEFAULT VALUES
The Matroska(TM) specification states that some elements have a default
value. Usually an element is not written to the file if its value is
equal to its default value in order to save space. The elements that
the user might miss in mkvinfo(1)'s output are the language and the
default track flag elements. The default value for the language is
English ('eng'), and the default value for the default track flag is
true. Therefore if you used --language 0:eng for a track then it will
not show up in mkvinfo(1)'s output.

ATTACHMENTS
Maybe you also want to keep some photos along with your Matroska(TM)
file, or you're using SSA subtitles and need a special TrueType(TM)
font that's really rare. In these cases you can attach those files to
the Matroska(TM) file. They will not be just appended to the file but
embedded in it. A player can then show those files (the 'photos' case)
or use them to render the subtitles (the 'TrueType(TM) fonts' case).

Here's an example how to attach a photo and a TrueType(TM) font to the
output file:

$ mkvmerge -o output.mkv -A video.avi sound.ogg \
--attachment-description "Me and the band behind the stage in a small get-together" \
--attachment-mime-type image/jpeg \
--attach-file me_and_the_band.jpg \
--attachment-description "The real rare and unbelievably good looking font" \
--attachment-type application/octet-stream \
--attach-file really_cool_font.ttf

If a Matroska(TM) containing attachments file is used as an input file
then mkvmerge(1) will copy the attachments into the new file. The
selection which attachments are copied and which are not can be changed
with the options --attachments and --no-attachments.

CHAPTERS
The Matroska(TM) chapter system is more powerful than the old known
system used by OGM files. The full specifications can be found at the
Matroska(TM) website[1].

mkvmerge(1) supports two kinds of chapter files as its input. The first
format, called 'simple chapter format', is the same format that the OGM
tools expect. The second format is a XML based chapter format which
supports all of Matroska(TM)'s chapter functionality.

The simple chapter format
This formmat consists of pairs of lines that start with 'CHAPTERxx='
and 'CHAPTERxxNAME=' respectively. The first one contains the start
timecode while the second one contains the title. Here's an example:

CHAPTER01=00:00:00.000
CHAPTER01NAME=Intro
CHAPTER02=00:02:30.000
CHAPTER02NAME=Baby prepares to rock
CHAPTER03=00:02:42.300
CHAPTER03NAME=Baby rocks the house

mkvmerge(1) will transform every pair or lines into one
Matroska(TM)ChapterAtom. It does not set any ChapterTrackNumber which
means that the chapters all apply to all tracks in the file.

As this is a text file character set conversion may need to be done.
See the section about text files and character sets for an explanation
how mkvmerge(1) converts between character sets.

The XML based chapter format
The XML based chapter format looks like this example:

<?xml version="1.0" encoding="ISO-8859-1"?>
<!DOCTYPE Chapters SYSTEM "matroskachapters.dtd">
<Chapters>
<EditionEntry>
<ChapterAtom>
<ChapterTimeStart>00:00:30.000</ChapterTimeStart>
<ChapterTimeEnd>00:01:20.000</ChapterTimeEnd>
<ChapterDisplay>
<ChapterString>A short chapter</ChapterString>
<ChapterLanguage>eng</ChapterLanguage>
</ChapterDisplay>
<ChapterAtom>
<ChapterTimeStart>00:00:46.000</ChapterTimeStart>
<ChapterTimeEnd>00:01:10.000</ChapterTimeEnd>
<ChapterDisplay>
<ChapterString>A part of that short chapter</ChapterString>
<ChapterLanguage>eng</ChapterLanguage>
</ChapterDisplay>
</ChapterAtom>
</ChapterAtom>
</EditionEntry>
</Chapters>

With this format three things are possible that are not possible with
the simple chapter format:

1. The timestamp for the end of the chapter can be set,

2. chapters can be nested,

3. the language and country can be set.

The mkvtoolnix distribution contains some sample files in the doc
subdirectory which can be used as a basis.

The following lists the supported XML tags, their data types and, where
appropriate, the valid range for their values:

Chapters (master)
EditionEntry (master)
EditionUID (unsigned integer, valid range: 1 <= value)
EditionFlagHidden (unsigned integer, valid range: 0 <= value <= 1)
EditionFlagDefault (unsigned integer, valid range: 0 <= value <= 1)
EditionFlagOrdered (unsigned integer, valid range: 0 <= value <= 1)
ChapterAtom (master)
ChapterAtom (master)
ChapterUID (unsigned integer, valid range: 1 <= value)
ChapterTimeStart (unsigned integer)
ChapterTimeEnd (unsigned integer)
ChapterFlagHidden (unsigned integer, valid range: 0 <= value <= 1)
ChapterFlagEnabled (unsigned integer, valid range: 0 <= value <= 1)
ChapterSegmentUID (binary, valid range: 1 <= length in bytes)
ChapterSegmentEditionUID (unsigned integer, valid range: 1 <= value)
ChapterPhysicalEquiv (unsigned integer)
ChapterTrack (master)
ChapterTrackNumber (unsigned integer, valid range: 1 <= value)
ChapterDisplay (master)
ChapterString (UTF-8 string)
ChapterLanguage (UTF-8 string)
ChapterCountry (UTF-8 string)
ChapterProcess (master)
ChapterProcessCodecID (unsigned integer)
ChapterProcessPrivate (binary)
ChapterProcessCommand (master)
ChapterProcessTime (unsigned integer)
ChapterProcessData (binary)

General notes
When splitting files mkvmerge(1) will correctly adjust the chapters as
well. This means that each file only includes the chapter entries that
apply to it, and that the timecodes will be offset to match the new
timecodes of each output file.

mkvmerge(1) is able to copy chapters from Matroska(TM) source files
unless this is explicitly disabled with the --no-chapters option. The
chapters from all sources (Matroska(TM) files, Ogg files, MP4 files,
chapter text files) are usually not merged but end up in separate
ChapterEditions. Only if chapters are read from several Matroska(TM) or
XML files that share the same edition UIDs will chapters be merged into
a single ChapterEdition. If such a merge is desired in other situations
as well then the user has to extract the chapters from all sources with
mkvextract(1) first, merge the XML files manually and mux them
afterwards.

TAGS
Introduction
Matroska(TM) supports an extensive set of tags that is deprecated and a
new, simpler system like it is is used in most other containers:
KEY=VALUE. However, in Matroska(TM) these tags can also be nested, and
both the KEY and the VALUE are elements of their own. The example file
example-tags-2.xml shows how to use this new system.

Scope of the tags
Matroska(TM) tags do not automatically apply to the complete file. They
can, but they also may apply to different parts of the file: to one or
more tracks, to one or more chapters, or even to a combination of both.
The the Matroska(TM) specification[4] gives more details about this
fact.

One important fact is that tags are linked to tracks or chapters with
the TargetsMatroska(TM) tag element, and that the UIDs used for this
linking are not the track IDs mkvmerge(1) uses everywhere. Instead the
numbers used are the UIDs which mkvmerge(1) calculates automatically
(if the track is taken from a file format other than Matroska(TM)) or
which are copied from the source file if the track's source file is a
Matroska(TM) file. Therefore it is difficult to know which UIDs to use
in the tag file before the file is handed over to mkvmerge(1).

mkvmerge(1) knows two options with which you can add tags to
Matroska(TM) files: The --global-tags and the --tags options. The
difference is that the former option, --global-tags, will make the tags
apply to the complete file by removing any of those Targets elements
mentioned above. The latter option, --tags, automatically inserts the
UID that mkvmerge(1) generates for the tag specified with the TID part
of the --tags option.

Example
Let's say that you want to add tags to a video track read from an AVI.
mkvmerge --identify file.avi tells you that the video track's ID (do
not mix this ID with the UID!) is 0. So you create your tag file, leave
out all Targets elements and call mkvmerge(1):

$ mkvmerge -o file.mkv --tags 0:tags.xml file.avi

Tag file format
mkvmerge(1) supports a XML based tag file format. The format is very
closely modeled after the Matroska(TM) specification[4]. Both the
binary and the source distributions of MKVToolNix come with a sample
file called example-tags-2.xml which simply lists all known tags and
which can be used as a basis for real life tag files.

The basics are:

o The outermost element must be <Tags>.

o One logical tag is contained inside one pair of <Tag>XML tags.

o White spaces directly before and after tag contents are ignored.

Data types
The new Matroska(TM) tagging system only knows two data types, a UTF-8
string and a binary type. The first is used for the tag's name and the
<String> element while the binary type is used for the <Binary>
element.

As binary data itself would not fit into a XML file mkvmerge(1)
supports two other methods of storing binary data. If the contents of a
XML tag starts with '@' then the following text is treated as a file
name. The corresponding file's content is copied into the Matroska(TM)
element.

Otherwise the data is expected to be Base64 encoded. This is an
encoding that transforms binary data into a limited set of ASCII
characters and is used e.g. in email programs. mkvextract(1) will
output Base64 encoded data for binary elements.

The deprecated tagging system knows some more data types which can be
found in the official Matroska(TM) tag specs. As mkvmerge(1) does not
support this system anymore these types aren't described here.

Known tags for the XML file format
The following lists the supported XML tags, their data types and, where
appropriate, the valid range for their values:

Tags (master)
Tag (master)
Targets (master)
TargetTypeValue (unsigned integer)
TargetType (UTF-8 string)
TrackUID (unsigned integer)
EditionUID (unsigned integer)
ChapterUID (unsigned integer)
AttachmentUID (unsigned integer)
Simple (master)
Simple (master)
Name (UTF-8 string)
TagLanguage (UTF-8 string)
DefaultLanguage (unsigned integer)
String (UTF-8 string)
Binary (binary)

THE SEGMENT INFO XML FILES
With a segment info XML file it is possible to set certain values in
the "segment information" header field of a Matroska(TM) file. All of
these values cannot be set via other command line options.

Other "segment information" header fields can be set via command line
options but not via the XML file. This includes e.g. the --title and
the --timecode-scale options.

There are other elements that can be set neither via command line
options nor via the XML files. These include the following elements:
DateUTC (also known as the "muxing date"), MuxingApp, WritingApp and
Duration. They're always set by mkvmerge(1) itself.

The following lists the supported XML tags, their data types and, where
appropriate, the valid range for their values:

Info (master)
SegmentUID (binary, valid range: length in bytes == 16)
SegmentFilename (UTF-8 string)
PreviousSegmentUID (binary, valid range: length in bytes == 16)
PreviousSegmentFilename (UTF-8 string)
NextSegmentUID (binary, valid range: length in bytes == 16)
NextSegmentFilename (UTF-8 string)
SegmentFamily (binary, valid range: length in bytes == 16)
ChapterTranslate (master)
ChapterTranslateEditionUID (unsigned integer)
ChapterTranslateCodec (unsigned integer)
ChapterTranslateID (binary)

MATROSKA(TM) FILE LAYOUT
The Matroska(TM) file layout is quite flexible. mkvmerge(1) will
render a file in a predefined way. The resulting file looks like this:

[EBML head] [segment {meta seek #1} [segment information] [track
information] {attachments} {chapters} [cluster 1] {cluster 2} ...
{cluster n} {cues} {meta seek #2} {tags}]

The elements in curly braces are optional and depend on the contents
and options used. A couple of notes:

o meta seek #1 includes only a small number of level 1 elements, and
only if they actually exist: attachments, chapters, cues, tags,
meta seek #2. Older versions of mkvmerge(1) used to put the
clusters into this meta seek element as well. Therefore some
imprecise guessing was necessary to reserve enough space. It often
failed. Now only the clusters are stored in meta seek #2, and meta
seek #1 refers to the meta seek element #2.

o Attachment, chapter and tag elements are only present if they were
added.

The shortest possible Matroska(TM) file would look like this:

[EBML head] [segment [segment information] [track information] [cluster
1]]

This might be the case for audio-only files.

EXTERNAL TIMECODE FILES
mkvmerge(1) allows the user to chose the timecodes for a specific track
himself. This can be used in order to create files with variable frame
rate video or include gaps in audio. A frame in this case is the unit
that mkvmerge(1) creates separately per Matroska(TM) block. For video
this is exactly one frame, for audio this is one packet of the specific
audio type. E.g. for AC-3 this would be a packet containing 1536
samples.

Timecode files that are used when tracks are appended to each other
must only be specified for the first part in a chain of tracks. For
example if you append two files, v1.avi and v2.avi, and want to use
timecodes then your command line must look something like this:

$ mkvmerge ... --timecodes 0:my_timecodes.txt v1.avi +v2.avi

There are four formats that are recognized by mkvmerge(1). The first
line always contains the version number. Empty lines, lines containing
only whitespace and lines beginning with '#' are ignored.

Timecode file format v1
This format starts with the version line. The second line declares the
default number of frames per second. All following lines contain three
numbers separated by commas: the start frame (0 is the first frame),
the end frame and the number of frames in this range. The FPS is a
floating point number with the dot '.' as the decimal point. The ranges
can contain gaps for which the default FPS is used. An example:

# timecode format v1
assume 27.930
800,1000,25
1500,1700,30

Timecode file format v2
In this format each line contains a timecode for the corresponding
frame. This timecode must be given in millisecond precision. It can be
a floating point number, but it doesn't have to be. You have to give at
least as many timecode lines as there are frames in the track. The
timecodes in this file must be sorted. Example for 25fps:

# timecode format v2
0
40
80

Timecode file format v3
In this format each line contains a duration in seconds followed by an
optional number of frames per second. Both can be floating point
numbers. If the number of frames per second is not present the default
one is used. For audio you should let the codec calculate the frame
timecodes itself. For that you should be using 0.0 as the number of
frames per second. You can also create gaps in the stream by using the
'gap' keyword followed by the duration of the gap. Example for an audio
file:

# timecode format v3
assume 0.0
25.325
7.530,38.236
gap, 10.050
2.000,38.236

Timecode file format v4
This format is identical to the v2 format. The only difference is that
the timecodes do not have to be sorted. This format should almost never
be used.

EXIT CODES
mkvmerge(1) exits with one of three exit codes:

o 0 -- This exit codes means that muxing has completed successfully.

o 1 -- In this case mkvmerge(1) has output at least one warning, but
muxing did continue. A warning is prefixed with the text
'Warning:'. Depending on the issues involved the resulting file
might be ok or not. The user is urged to check both the warning and
the resulting file.

o 2 -- This exit code is used after an error occurred. mkvmerge(1)
aborts right after outputting the error message. Error messages
range from wrong command line arguments over read/write errors to
broken files.

ENVIRONMENT VARIABLES
mkvmerge(1) uses the default variables that determine the system's
locale (e.g. LANG and the LC_* family). Additional variables:

MKVMERGE_DEBUG, MKVTOOLNIX_DEBUG and its short form MTX_DEBUG
The content is treated as if it had been passed via the --debug
option.

MKVMERGE_ENGAGE, MKVTOOLNIX_ENGAGE and its short form MTX_ENGAGE
The content is treated as if it had been passed via the --engage
option.

MKVMERGE_OPTIONS, MKVTOOLNIX_OPTIONS and its short form MTX_OPTIONS
The content is split on white space. The resulting partial strings
are treated as if it had been passed as command line options. If
you need to pass special characters (e.g. spaces) then you have to
escape them (see the section about escaping special characters in
text).

SEE ALSO
mkvinfo(1), mkvextract(1), mkvpropedit(1), mkvtoolnix-gui(1)

WWW
The latest version can always be found at the MKVToolNix homepage[5].

AUTHOR
Moritz Bunkus <moritz@bunkus.org>
Developer

NOTES
1. the Matroska(TM) website
http://www.matroska.org/

2. the IANA homepage
http://www.iana.org/assignments/media-types/

3. mkvmerge-identification-output-schema.json
https://mkvtoolnix.download/doc/mkvmerge-identification-output-
schema.json

4. the Matroska(TM) specification
http://matroska.org/technical/specs/index.html

5. the MKVToolNix homepage
https://mkvtoolnix.download/

MKVToolNix 8.8.0 2016-01-10 MKVMERGE(1)