NAME¶
mkvextract - extract tracks from Matroska files into other
files
SYNOPSIS¶
mkvextract {source-filename} {mode1} [options]
[extraction-spec1] [mode2] [options] [extraction-spec2] [...]
DESCRIPTION¶
This program extracts specific parts from a Matroska file to other
useful formats. The first argument is the name of the source file which must
be a Matroska file.
All other arguments either switch to a certain extraction mode,
change options for the currently active mode or specify what to extract into
which file. Multiple modes can be used in the same invocation of mkvextract
allowing the extraction of multiple things in a single pass. Most options
can only be used in certain modes with a few options applying to all
modes.
Currently supported is the extraction of tracks, tags,
attachments, chapters, CUE sheets, timestamps and cues.
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.
--flush-on-close
Tells the program to flush all data cached in memory to
storage when closing files opened for writing. This can be used to prevent
data loss on power outages or to circumvent certain problems in the operating
system or drivers. The downside is that multiplexing will take longer as
mkvmerge will wait until all data has been written to the storage before
exiting. See issues #2469 and #2480 on the MKVToolNix bug tracker for in-depth
discussions on the pros and cons.
--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.
--abort-on-warnings
Tells the program to abort after the first warning is
emitted. The program's exit code will be 1.
--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.
@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 source-filename
tracks [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 input.mkv tracks 0:video.h264 2:output-two-vobsub-tracks.idx 3:output-two-vobsub-tracks.idx
Syntax: mkvextract source-filename
attachments [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 source-filename
chapters [options]
output-filename.xml
-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 chapters are written to specified output file. By default the
XML format understood by mkvmerge(1) is used. If no chapters are
found in the file, the output file is not created.
Syntax: mkvextract source-filename
tags [options]
output-filename.xml
The tags are written to specified output file in the XML format
understood by mkvmerge(1). If no tags are found in the file, the
output file is not created.
Syntax: mkvextract source-filename
cuesheet [options]
output-filename.cue
The cue sheet is written to specified output file. If no chapters
or tags are found in the file, the output file is not created.
Syntax: mkvextract source-filename
timestamps_v2 [options]
TID1:dest-filename1
[TID2:dest-filename2 ...]
TID:outname
Causes extraction of the timestamps 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 input.mkv timestamps_v2 1:ts-track1.txt 2:ts-track2.txt
Syntax: mkvextract source-filename
cues [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:
timestamp=00:00:13.305000000 duration=- cluster_position=757741 relative_position=11
The possible keys are:
timestamp
The cue point's timestamp 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 input.mkv cues 1:cues-track1.txt 2:cues-track2.txt
EXAMPLES¶
Extracting both chapters and tags in their respective XML formats
at the same time:
$ mkvextract movie.mkv chapters movie-chapters.xml tags movie-tags.xml
Extracting a couple of tracks and their respective timestamps at
the same time:
$ mkvextract "Another Movie.mkv" tracks 0:video.h265 "1:main audio.aac" "2:director's comments.aac" timestamps_v2 "0:timestamps video.txt" "1:timestamps main audio.txt" "2:timestamps director's comments.txt"
Extracting chapters in the Ogg/OGM format and re-encoding a text
subtitle track to another character set:
$ mkvextract "My Movie.mkv" chapters --simple "My Chapters.txt" tracks -c MS-ANSI "2:My Subtitles.srt"
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:
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_AC3, A_EAC3
These will be extracted to raw AC-3 files.
A_ALAC
ALAC tracks are written to CAF files.
A_DTS
These will be extracted to raw DTS files.
A_FLAC
FLAC tracks are written to raw FLAC files.
A_MPEG/L2
MPEG-1 Audio Layer II streams will be extracted to raw
MP2 files.
A_MPEG/L3
These will be extracted to raw MP3 files.
A_OPUS
Opus tracks are written to OggOpus files.
A_PCM/INT/LIT, A_PCM/INT/BIG
Raw PCM data will be written to a WAV file. Big-endian
integer data will be converted to little-endian data in the process.
A_REAL/*
RealAudio tracks are written to RealMedia files.
A_TRUEHD, A_MLP
These will be extracted to raw TrueHD/MLP files.
A_TTA1
TrueAudio tracks are written to TTA files. Please note
that due to Matroska's limited timestamp 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_VORBIS
Vorbis audio will be written into an OggVorbis
file.
A_WAVPACK4
WavPack tracks are written to WV files.
S_HDMV/PGS
PGS subtitles will be written as SUP files.
S_HDMV/TEXTST
S_KATE
Kate streams will be written within an Ogg
container.
S_TEXT/SSA, S_TEXT/ASS, S_SSA, S_ASS
SSA and ASS text subtitles will be written as SSA/ASS
files respectively.
S_TEXT/UTF8, S_TEXT/ASCII
Simple text subtitles will be written as SRT files.
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_TEXT/WEBVTT
WebVTT text subtitles will be written as WebVTT
files.
V_MPEG1, V_MPEG2
MPEG-1 and MPEG-2 video tracks will be written as MPEG
elementary streams.
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_MPEG4/ISO/HEVC
H.265 / HEVC video tracks are written to H.265 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.
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 the 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.
Timestamps
Timestamps are first sorted and then output as a
timestamp 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 code 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.
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.
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