MKVToolnix 51.0.0 ‘I Wish’

Video File Editor


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MKVToolnix GUI DOWNLOADMKVToolNix is one of the best collection of tools (mkvmerge, mkvinfo, mkvextract, mkvpropedit, and mmg) for modifying MKV files.

With these tools, one can get information about (via mkvinfo) Matroska files, extract tracks/data from (via mkvextract) Matroska files, and create (via mkvmerge) Matroska files from other media files. Matroska is a new multimedia file format aiming to become THE new container format for the future. You can find more information about it and its underlying technology, the Extensible Binary Meta Language (EBML), at

The graphical user interface (GUI) allows you to manipulate Matroska (MKV) files in several ways. You can use those tools to create, split, edit, mux, demux, merge, extract, or inspect Matroska files.

MKVToolnix will also work with other video formats. Such as AVI, MPEG, MP4, MPEG, Ogg/OGM, RealVideo, MPEG1/2, H264/AVC, Dirac, VC1.

And more as well as some video codecs such as VP9 video codec support – reading from IVF, Matroska, WebM files, extract to IVF files.

Moreover, the program can work with audio files such as AAC, FLAC, MP2, MP3, AC3, DTS/DTS-HD, Vorbis, RealAudio. And also work with most subtitle formats including SRT, PGS/ SUP, VobSub, ASS, and SSA.

It is a cross-platform application that will work on Microsoft Windows (both 32 and 64-bit versions), Apple macOS, and Linux operating systems.

Here is also the portable version which does not require installation. You just need to start the function. It can also be stored on external devices and run on any computer you have access to.

Changes in MKVToolnix 51.0.0 “Awakenings”:

New features and enhancements

  • mkvmerge, mkvpropedit, MKVToolNix GUI: IETF BCP 47 language tags: added missing support for UN M.49 regions for which there is no corresponding ISO 3166 alpha codes. This enables language tags such as `es-419` = Spanish in bLatin America and the Caribbean.MKVToolNix GUI: IETF BCP 47 language tags: the text in the widget displaying the current language & the corresponding edit button is now displayed like a link (depending on the theme: different color & underlined), making it clearer that not just the edit button can be clicked but the text, too.

Bug fixes

  • mkvmerge: AV1 parser: fixed mkvmerge crashing after uncaught exceptions due to certain data conditions. Found by fuzzing.
  • mkvmerge: AV1 packetizer: the duration of frames wasn’t set properly. When appending AV1 IVF or OBU files this meant that the last frame of the Nth file and the first frame of file N+1 had the same timestamp.
  • mkvmerge: DTS reader: fixed handling of buffers with an odd length when byte-swapped DTS is detected so that mkvmerge doesn’t abort with a failed assertion. Found by fuzzing.
  • mkvmerge: h.264/AVC and h.265/HEVC elementary stream readers: mkvmerge will no longer claim to recognize data that looks like AVC or HEVC but with invalid video width/height values as that lead to failed assertions in libEBML later. Found by fuzzing.
  • mkvmerge: h.265/HEVC parser: fixed mkvmerge aborting after uncaught exceptions due to certain data constellations found by fuzzying.
  • mkvmerge: IVF reader: fixed mkvmerge crashing with a “division by zero” error due to certain data conditions. Found by fuzzing.
  • mkvmerge: fixed mkvmerge aborting with a “division by zero” error due to the timestamp scaling factor being 0 after handling certain data constellations found by fuzzing.
  • mkvmerge: track statistics: fixed a “division by zero” error when the content’s shorter than 1ms. Found by fuzzing.
  • mkvmerge, mkvinfo, mkvextract, mkvpropedit: Matroska access class: fixed invalid memory access under certain data conditions. Found by fuzzing.
  • MKVToolNix GIU: IETF BCP 47/RFC 5646 language tags: the GUI will no longer open the language dialog when clicking on a disabled language display widget.
  • MKVToolNix GUI: IETF BCP 47 language tags: the “variants” combo-boxes were not populated even when the language tag was valid and contained at a variant.
  • MKVToolNix GUI: IETF BCP 47 language tags: when no language is selected, at least one of the other components (extended subtags, region, or variants) has something selected and “private use” is not empty, the GUI would claim this to be a valid tag, which it isn’t.
  • MKVToolNix GUI: multiplexer: when the tracks/chapters/tags selection changes from “at least one entry selected” to “no entry selected”, the input controls will be reset to their default state and not just disabled.

Build system changes

  • * `configure` now checks for the presence of the system-wide installed copy of the JPCRE2 C++ wrapper library for the PCRE2 library and uses that if it’s new enough (at least v10.32.1). If not, the bundled version will be used as a fallback.

Works on Microsoft Windows (both 32 and 64-bit versions), Apple macOS, and Linux operating systems.

Size: 17.6 MB

DOWNLOAD MKVToolnix 32-Bit Installer

DOWNLOAD MKVToolnix 64-Bit Installer

DOWNLOAD MKVToolnix 32-Bit Portable

DOWNLOAD MKVToolnix 64-Bit Portable

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