NAME¶
mkvextract - extract tracks from Matroska files into other
files
SYNOPSIS¶
mkvextract {mode} {source-filename} [options]
[extraction-spec]
DESCRIPTION¶
This program extracts specific parts from a Matroska file to other
useful formats. The first argument, mode, tells mkvextract(1)
what to extract. Currently supported is the extraction of tracks, tags,
attachments, chapters, CUE sheets, timecodes and cues. The second argument
is the name of the source file. It must be a Matroska file. All following
arguments are options and extraction specifications; both of which depend on
the selected mode.
Common options¶
The following options are available in all modes and only
described once in this section.
-f, --parse-fully
Sets the parse mode to 'full'. The default mode does not
parse the whole file but uses the meta seek elements for locating the required
elements of a source file. In 99% of all cases this is enough. But for files
that do not contain meta seek elements or which are damaged the user might
have to use this mode. A full scan of a file can take a couple of minutes
while a fast scan only takes seconds.
--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.
--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). Entering 'list' as the
code will cause the program 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 mkvextract --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.
-v, --verbose
Be verbose and show all the important Matroska elements
as they're read.
-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.
@options-file.json
Reads additional command line arguments from the file
options-file. For a full explanation on the supported formats for such
files see the section called "Option files" in the
mkvmerge(1) man page.
Syntax: mkvextract tracks
source-filename [options]
TID1:dest-filename1
[TID2:dest-filename2 ...]
The following command line options are available for each track in
the 'tracks' extraction mode. They have to appear in front of the track
specification (see below) they should be applied to.
-c character-set
Sets the character set to convert the next text subtitle
track to. Only valid if the next track ID targets a text subtitle track. It
defaults to UTF-8.
--blockadd level
Keep only the BlockAdditions up to this level. The
default is to keep all levels. This option only affects certain kinds of
codecs like WAVPACK4.
--cuesheet
Causes mkvextract(1) to extract a CUE sheet from
the chapter information and tag data for the following track into a file whose
name is the track's output name with '.cue' appended to it.
--raw
Extracts the raw data into a file without any container
data around it. Unlike the --fullraw flag this flag does not cause the
contents of the CodecPrivate element to be written to the file. This mode
works with all CodecIDs, even the ones that mkvextract(1) doesn't
support otherwise, but the resulting files might not be usable.
--fullraw
Extracts the raw data into a file without any container
data around it. The contents of the CodecPrivate element will be written to
the file first if the track contains such a header element. This mode works
with all CodecIDs, even the ones that mkvextract(1) doesn't support
otherwise, but the resulting files might not be usable.
TID:outname
Causes extraction of the track with the ID
TID
into the file
outname if such a track exists in the source file. This
option can be given multiple times. The track IDs are the same as the ones
output by
mkvmerge(1)'s
--identify option.
Each output name should be used only once. The exception are
RealAudio and RealVideo tracks. If you use the same name for different
tracks then those tracks will be saved in the same file. Example:
$ mkvextract tracks input.mkv 1:output-two-tracks.rm 2:output-two-tracks.rm
Syntax: mkvextract tags
source-filename [options]
The extracted tags are written to the console unless the output is
redirected (see the section about output redirection for details).
Syntax: mkvextract attachments
source-filename [options]
AID1:outname1 [AID2:outname2 ...]
AID:outname
Causes extraction of the attachment with the ID
AID into the file outname if such an attachment exists in the
source file. If the outname is left empty then the name of the
attachment inside the source Matroska file is used instead. This option can be
given multiple times. The attachment IDs are the same as the ones output by
mkvmerge(1)'s --identify option.
Syntax: mkvextract chapters
source-filename [options]
-s, --simple
Exports the chapter information in the simple format used
in the OGM tools (CHAPTER01=..., CHAPTER01NAME=...). In this mode some
information has to be discarded. Default is to output the chapters in XML
format.
--simple-language language
If the simple format is enabled then
mkvextract(1)
will only output a single entry for each chapter atom encountered even if a
chapter atom contains more than one chapter name. By default
mkvextract(1) will use the first chapter name found for each atom
regardless of its language.
Using this option allows the user to determine which chapter names
are output if atoms contain more than one chapter name. The language
parameter must be an ISO 639-1 or ISO 639-2 code.
The extracted chapters are written to the console unless the
output is redirected (see the section about output redirection for
details).
Syntax: mkvextract cuesheet
source-filename [options]
The extracted cue sheet is written to the console unless the
output is redirected (see the section about output redirection for
details).
Syntax: mkvextract timecodes_v2
source-filename [options]
TID1:dest-filename1
[TID2:dest-filename2 ...]
The extracted timecodes are written to the console unless the
output is redirected (see the section about output redirection for
details).
TID:outname
Causes extraction of the timecodes for the track with the
ID
TID into the file
outname if such a track exists in the
source file. This option can be given multiple times. The track IDs are the
same as the ones output by
mkvmerge(1)'s
--identify option.
Example:
$ mkvextract timecodes_v2 input.mkv 1:tc-track1.txt 2:tc-track2.txt
Syntax: mkvextract cues
source-filename [options]
TID1:dest-filename1
[TID2:dest-filename2 ...]
TID:dest-filename
Causes extraction of the cues for the track with the ID
TID into the file outname if such a track exists in the source
file. This option can be given multiple times. The track IDs are the same as
the ones output by mkvmerge(1)'s --identify option and not the
numbers contained in the CueTrack element.
The format output is a simple text format: one line per CuePoint
element with key=value pairs. If an optional element is not present in a
CuePoint (e.g. CueDuration) then a dash will be output as the value.
Example:
timecode=00:00:13.305000000 duration=- cluster_position=757741 relative_position=11
The possible keys are:
timecode
The cue point's timecode with nanosecond precision. The
format is HH:MM:SS.nnnnnnnnn. This element is always set.
duration
The cue point's duration with nanosecond precision. The
format is HH:MM:SS.nnnnnnnnn.
cluster_position
The absolute position in bytes inside the Matroska file
where the cluster containing the referenced element starts.
Note
Inside the Matroska file the CueClusterPosition is relative to the segment's
data start offset. The value output by
mkvextract(1)'s cue extraction
mode, however, contains that offset already and is an absolute offset from the
beginning of the file.
relative_position
The relative position in bytes inside the cluster where
the BlockGroup or SimpleBlock element the cue point refers to starts.
Note
Inside the Matroska file the CueRelativePosition is relative to the cluster's
data start offset. The value output by
mkvextract(1)'s cue extraction
mode, however, is relative to the cluster's ID. The absolute position inside
the file can be calculated by adding cluster_position and relative_position.
Example:
$ mkvextract cues input.mkv 1:cues-track1.txt 2:cues-track2.txt
OUTPUT REDIRECTION¶
Several extraction modes cause mkvextract(1) to write the
extracted data to the console. There are generally two ways of writing this
data into a file: one provided by the shell and one provided by
mkvextract(1) itself.
The shell's builtin redirection mechanism is used by appending
'> output-filename.ext' to the command line. Example:
$ mkvextract tags source.mkv > tags.xml
mkvextract(1)'s own redirection is invoked with the
--redirect-output option. Example:
$ mkvextract tags source.mkv --redirect-output tags.xml
Note
On Windows you should probably use the --redirect-output
option because cmd.exe sometimes interpretes special characters
before they're written into the output file resulting in broken output.
TEXT FILES AND CHARACTER SET CONVERSIONS¶
For an in-depth discussion about how all tools in the MKVToolNix
suite handle character set conversions, input/output encoding, command line
encoding and console encoding please see the identically-named section in
the mkvmerge(1) man page.
The decision about the output format is based on the track type,
not on the extension used for the output file name. The following track
types are supported at the moment:
V_MPEG4/ISO/AVC
H.264 / AVC video tracks are written to H.264 elementary
streams which can be processed further with e.g. MP4Box from the GPAC
package.
V_MS/VFW/FOURCC
Fixed FPS video tracks with this CodecID are written to
AVI files.
V_REAL/*
RealVideo tracks are written to RealMedia files.
V_THEORA
Theora streams will be written within an Ogg
container
V_VP8, V_VP9
VP8 / VP9 tracks are written to IVF files.
A_MPEG/L2
MPEG-1 Audio Layer II streams will be extracted to raw
MP2 files.
A_MPEG/L3, A_AC3
These will be extracted to raw MP3 and AC-3 files.
A_PCM/INT/LIT
Raw PCM data will be written to a WAV file.
A_AAC/MPEG2/*, A_AAC/MPEG4/*, A_AAC
All AAC files will be written into an AAC file with ADTS
headers before each packet. The ADTS headers will not contain the deprecated
emphasis field.
A_VORBIS
Vorbis audio will be written into an OggVorbis
file.
A_REAL/*
RealAudio tracks are written to RealMedia files.
A_TTA1
TrueAudio tracks are written to TTA files. Please note
that due to Matroska's limited timecode precision the extracted file's header
will be different regarding two fields: data_length (the total number
of samples in the file) and the CRC.
A_ALAC
ALAC tracks are written to CAF files.
A_FLAC
FLAC tracks are written to raw FLAC files.
A_WAVPACK4
WavPack tracks are written to WV files.
A_OPUS
Opus tracks are written to OggOpus files.
S_TEXT/UTF8
Simple text subtitles will be written as SRT files.
S_TEXT/SSA, S_TEXT/ASS
SSA and ASS text subtitles will be written as SSA/ASS
files respectively.
S_KATE
Kate streams will be written within an Ogg
container.
S_VOBSUB
VobSub subtitles will be written as SUB files along with
the respective index files, as IDX files.
S_TEXT/USF
USF text subtitles will be written as USF files.
S_HDMV/PGS
PGS subtitles will be written as SUP files.
Tags
Tags are converted to a XML format. This format is the
same that mkvmerge(1) supports for reading tags.
Attachments
Attachments are written to they output file as they are.
No conversion whatsoever is done.
Chapters
Chapters are converted to a XML format. This format is
the same that mkvmerge(1) supports for reading chapters. Alternatively
a stripped-down version can be output in the simple OGM style format.
Timecodes
Timecodes are first sorted and then output as a timecode
v2 format compliant file ready to be fed to mkvmerge(1). The extraction
to other formats (v1, v3 and v4) is not supported.
EXIT CODES¶
mkvextract(1) exits with one of three exit codes:
•0 -- This exit codes means that extraction
has completed successfully.
•1 -- In this case mkvextract(1) has
output at least one warning, but extraction did continue. A warning is
prefixed with the text 'Warning:'. Depending on the issues involved the
resulting files might be ok or not. The user is urged to check both the
warning and the resulting files.
•2 -- This exit code is used after an error
occurred. mkvextract(1) aborts right after outputting the error
message. Error messages range from wrong command line arguments over
read/write errors to broken files.
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' and '\' (a single
backslash) itself becomes '\\'.
ENVIRONMENT VARIABLES¶
mkvextract(1) uses the default variables that determine the
system's locale (e.g. LANG and the LC_* family). Additional
variables:
MKVEXTRACT_DEBUG, MKVTOOLNIX_DEBUG and its short
form MTX_DEBUG
The content is treated as if it had been passed via the
--debug option.
MKVEXTRACT_ENGAGE, MKVTOOLNIX_ENGAGE and its short
form MTX_ENGAGE
The content is treated as if it had been passed via the
--engage option.
MKVEXTRACT_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¶
mkvmerge(1), mkvinfo(1), mkvpropedit(1),
mkvtoolnix-gui(1)
WWW¶
The latest version can always be found at the MKVToolNix
homepage[1].
AUTHOR¶
Moritz Bunkus <moritz@bunkus.org>
Developer
NOTES¶
- 1.
- the MKVToolNix homepage