{{short description|Multimedia container open file format}} {{Multiple issues| {{Sources exist|date=April 2024}} {{Primary sources|date=September 2021}} }}{{Redirect|.mkv|3=MKV (disambiguation)}}{{Infobox file format | name = Matroska | icon = 64px|MKV Extension Icon | logo = | extension = .mkv .mk3d .mka .mks | mime = video/matroska video/matroska-3d audio/matroska<ref>{{cite web|url=https://www.iana.org/assignments/media-types/media-types.xhtml|title=Media Types|access-date=August 5, 2024}}</ref> application/octet-stream{{efn|For .mks.}} | extendedfrom = MCF, EBML | released = {{start date and age|2002|12|06|df=yes}} | latest_release_version = 1.7.1<ref>{{cite web|url=https://github.com/Matroska-Org/libmatroska/releases/tag/release-1.7.1/|date=October 8, 2022|website=github.com|title=Release release-1.7.1 · Matroska-Org/Libmatroska|access-date=February 28, 2023|archive-date=February 28, 2023|archive-url=https://web.archive.org/web/20230228143120/https://github.com/Matroska-Org/libmatroska/releases/tag/release-1.7.1/|url-status=live}}</ref> | latest_release_date = {{start date and age|2022|10|08|df=yes}} | developer = | genre = Container format | container for = Multimedia | standard = {{IETF RFC|9559}} | open = Yes | free = Yes<ref>{{cite tech report |publisher=Library of Congress |location=Washington, D.C. |series=Sustainability of Digital Formats |type=Partial draft |title=Matroska Multimedia Container |date=21 December 2015 |url=https://www.loc.gov/preservation/digital/formats/fdd/fdd000342.shtml |access-date=13 December 2021}}</ref> | url = {{URL|https://matroska.org/}} }}
'''Matroska''' (styled '''Matroška''') is a project to create a container format that can hold an unlimited number of video, audio, picture, or subtitle tracks in one file.<ref>[https://www.matroska.org/technical/elements.html Matroska v4 element specification] {{Webarchive|url=https://web.archive.org/web/20180204034747/https://www.matroska.org/technical/specs/index.html |date=2018-02-04 }}, Matroska.org. "TrackNumber: The track number as used in the Block Header (using more than 127 tracks is not encouraged, though the design allows an unlimited number)."</ref> The '''Matroska Multimedia Container''' is similar in concept to other containers like AVI, MP4, or Advanced Systems Format (ASF), but is an open standard.
Matroska file extensions are ''.mkv'' for video (which may include audio, subtitles and chapters), ''.mk3d'' for stereoscopic video, ''.mka'' for audio-only files (which may include subtitles), and ''.mks'' for subtitles only.<ref name="mk3d">{{cite web |url=https://www.matroska.org/technical/guides/faq/index.html#q3 |title=Matroska FAQ - Q3: What file extensions does Matroska use? |website=www.matroska.org |language=en |access-date=2018-07-16 |url-status=dead |archive-date=2019-04-08 |archive-url=https://web.archive.org/web/20190408035211/https://matroska.org/technical/guides/faq/index.html#q3}}</ref>
== History ==
The project was announced on 6 December 2002<ref>{{cite web |title=Matroska: Older Archives |url=https://www.matroska.org/news/archives2.html |access-date=2020-05-25 |archive-date=2017-08-03 |archive-url=https://web.archive.org/web/20170803012039/https://www.matroska.org/news/archives2.html |url-status=dead }}</ref> as a fork of the Multimedia Container Format (MCF), after disagreements between MCF lead developer Lasse Kärkkäinen<ref name="trepo/10024/114739"> *{{cite journal |last1=Nurmi |first1=Juha |title=Understanding the Usage of Anonymous Onion Services: Empirical Experiments to Study Criminal Activities in the Tor Network |journal=Dissertations, 62 |date=2019 |url=https://www.finna.fi/Record/trepo.10024_114739 |access-date=28 May 2026 |publisher=Tampere University |issn=|isbn=978-952-03-1091-2 |quote=In 2014, under his pseudonym Douppikauppa, he sent free LSD samples around Finland. Douppikauppa is the leader of the syndicate of multiple sellers who created a common brand in Silkkitie marketplace. In the open-source software world he is known under pseudonym Tronic and was the former lead developer of a container format specification known as Multimedia Container Format, MCF. Also, he kept his daily work as a software developer and simultaneously led the criminal organization. Furthermore, in 2015, he was a candidate in Finnish parliamentary elections. A year after this 32-year-old chief technology officer and software developer Lasse Kärkkäinen was arrested.}} *[https://web.archive.org/web/20220327052730/https://trepo.tuni.fi/bitstream/handle/10024/114739/TUNI_nurmi.pdf TUNI_nurmi.pdf] 2022-03-27</ref> and soon-to-be Matroska founder Steve Lhomme about the use of the Extensible Binary Meta Language (EBML) instead of a binary format.<ref>{{cite newsgroup |title=Re: Proposed Spec Changes |author=Lhomme, Steve |date=2002-12-06 |newsgroup=gmane.comp.video.mcf.devel |url=http://article.gmane.org/gmane.comp.video.mcf.devel/673 |access-date=May 23, 2016 |url-status=dead |archive-url=https://web.archive.org/web/20161011215209/http://article.gmane.org/gmane.comp.video.mcf.devel/673 |archive-date=October 11, 2016}}</ref> This coincided with a 6-month coding break by the MCF's lead developer for his military service, during which most of the community quickly migrated to the new project.{{Citation needed|date=March 2010}}
In 2010, it was announced that the WebM audio/video format would be based on a profile of the Matroska container format together with VP8 video and Vorbis audio.<ref>[https://www.webmproject.org/about/faq/ ''Frequently Asked Questions''] {{Webarchive|url=https://web.archive.org/web/20210922124446/https://www.webmproject.org/about/faq/ |date=2021-09-22 }}, the WebM project</ref>
On 31 October 2014, Microsoft confirmed that Windows 10 would support HEVC and Matroska out of the box, according to a statement from Gabriel Aul, the leader of Microsoft Operating Systems Group's Data and Fundamentals Team.<ref name=TwitterHEVCNovember2014W10>{{cite news |title=HEVC also supported in-box. |author=Gabriel Aul |publisher=Twitter |url=https://twitter.com/GabeAul/status/528401061779107841 |date=October 31, 2014 |access-date=November 3, 2014 |archive-date=December 29, 2020 |archive-url=https://web.archive.org/web/20201229183259/https://twitter.com/GabeAul/status/528401061779107841 |url-status=live }}</ref><ref name=WCHEVCNovember2014W10>{{cite news |title=Microsoft: Windows 10 will support the HEVC video compression standard |author=John Callaham |publisher=Windows Central |url=https://www.windowscentral.com/microsoft-windows-10-will-support-hevc-video-standard |date=November 1, 2014 |access-date=2020-05-25 |url-status=live |archive-url=https://web.archive.org/web/20201229181717/https://www.windowscentral.com/microsoft-windows-10-will-support-hevc-video-standard |archive-date=2020-12-29}}</ref> Windows 10 Technical Preview Build 9860 added platform level support for HEVC and Matroska.<ref name=SoftpediaHEVCNovember2014W10>{{cite news |title=Microsoft Confirms MKV File Support in Windows 10 |author=Bogdan Popa |publisher=Softpedia|date=November 3, 2014 |url=https://news.softpedia.com/news/Microsoft-Confirms-MKV-File-Support-in-Windows-10-463791.shtml |access-date=2020-05-25 |url-status=live |archive-date=2017-10-05 |archive-url=https://web.archive.org/web/20171005101533/http://news.softpedia.com/news/Microsoft-Confirms-MKV-File-Support-in-Windows-10-463791.shtml}}</ref><ref name=MicrosoftHEVCNovember2014W10>{{cite news |title=New build available to the Windows Insider Program |author=Gabe Aul |publisher=Microsoft |url=http://blogs.windows.com/bloggingwindows/2014/11/12/new-build-available-to-the-windows-insider-program/ |date=November 12, 2014 |access-date=November 15, 2014 |url-status=live |archive-url=https://web.archive.org/web/20150303084809/http://blogs.windows.com/bloggingwindows/2014/11/12/new-build-available-to-the-windows-insider-program/ |archive-date=March 3, 2015}}</ref>
In October 2024, Matroska was formally specified in and published as {{IETF RFC|9559}}.
== Name and logo ==
"Matroska" is derived from ''matryoshka'' ({{langx|ru|матрёшка}} {{IPA|ru|mɐˈtrʲɵʂkə|}}), the Russian name for the hollow wooden dolls, better known in English as Russian nesting dolls, which open to expose another smaller doll, that in turn opens to expose another doll, and so on. The logo writes it as "Matroška"; the letter š, an "s" with a caron over it, represents the "sh" sound ({{IPA|/ʂ/}}) in various languages.<ref>{{Cite web |title=Matroska Media Container Homepage |url=https://matroska.org/index.html |access-date=2023-04-11 |website=matroska.org |archive-date=2023-04-11 |archive-url=https://web.archive.org/web/20230411102634/https://matroska.org/index.html |url-status=live }}</ref>
== Design == {{expand section|date=September 2021}}
The use of EBML allows extension for future format changes. The Matroska team has expressed some of their long-term goals on Doom9.org and Hydrogenaudio forums. Thus, the following are "goals", not necessarily existing features, of Matroska:<ref name="matroska.org">{{cite web |url=https://matroska.org/what_is_matroska.html |title=What is Matroska? |website=matroska.org |language=en|access-date=2020-05-25 |url-status=live |archive-url=https://web.archive.org/web/20201229181717/https://matroska.org/what_is_matroska.html |archive-date=2020-12-29}}</ref>
* Creating a modern, flexible, extensible, cross-platform multimedia container format * Developing robust streaming support (both this format and the WebM subset are streamable)<ref>{{cite web |title=Streaming |url=https://matroska.org/technical/streaming/index.html |website=matroska.org |access-date=2019-06-30 |url-status=live |archive-url=https://web.archive.org/web/20201229181812/https://matroska.org/technical/streaming.html |archive-date=2020-12-29}}</ref> * Developing a menu system similar to that of DVDs based on EBML ({{As of|2019|07|lc=1}}, there is only a mostly empty draft)<ref>{{cite web |title=Menu Specifications |url=https://matroska.org/technical/menu/index.html |website=matroska.org |access-date=30 June 2019 |url-status=live |archive-url=https://web.archive.org/web/20201229181807/https://matroska.org/technical/menu.html |archive-date=29 December 2020}}</ref> * Developing a set of tools for the creation and editing of Matroska files (MKVToolNix, for example) * Developing libraries to allow developers to add Matroska support to their applications (made open source by Matroska developers) * Working with hardware manufacturers to include Matroska support in embedded multimedia devices
== Development ==
Matroska is supported by a non-profit organization registered in France.<ref>{{cite web |url=https://matroska.org/legal.html |title=Legal Aspect - Matroska |website=matroska.org |access-date=2020-08-01 |url-status=live |archive-date=2020-12-29 |archive-url=https://web.archive.org/web/20201229181802/https://matroska.org/legal.html}}</ref> It is a royalty-free open standard that is free to use, with the specification being freely available for both private and commercial use. The Matroska development team licenses its libraries under the LGPL, with parsing and playback libraries available under BSD licenses.<ref name="matroska.org"/>
== Support ==
Software supporting Matroska include all ffmpeg-based ones,<ref>{{Cite web|url=https://ffmpeg.org/general.html#Supported-File-Formats_002c-Codecs-or-Features|title=General Documentation|website=ffmpeg.org|access-date=2022-11-21|archive-date=2012-01-06|archive-url=https://web.archive.org/web/20120106131336/http://ffmpeg.org/general.html#Supported-File-Formats_002c-Codecs-or-Features|url-status=live}}</ref> including, notably, mplayer, mpv, VLC, Foobar2000, Media Player Classic-HC, Google Chrome, Mozilla Firefox, Blender, Kdenlive, HandBrake, MKVToolNix as well as YouTube (which uses WebM extensively)<!-- Can somebody turn this into actual external sources?: Category:Software that uses FFmpeg,FFmpeg#Projects_using_FFmpeg -->,<ref name="third_party">{{Cite web|url=https://matroska.org/downloads/third_party.html|title=Third-party applications - Matroska|access-date=2021-05-26|archive-date=2021-04-21|archive-url=https://web.archive.org/web/20210421011702/https://matroska.org/downloads/third_party.html|url-status=live}}</ref> and OBS Studio.<ref>{{Cite web |title=Audio/Video Formats Guide {{!}} OBS |url=https://obsproject.com/kb/audio-video-formats-guide |access-date=2024-10-01 |website=obsproject.com}}</ref>
Outside of ffmpeg, Windows 10 supports Matroska natively as well.<ref>{{Cite web|url = https://www.groovypost.com/news/windows-10-native-mkv-flac-support/|title = More on Native Flac and MKV Support in Windows 10|date = 5 January 2015|access-date = 31 October 2021|archive-date = 6 January 2024|archive-url = https://web.archive.org/web/20240106030205/https://www.groovypost.com/news/windows-10-native-mkv-flac-support/|url-status = live}}</ref> Earlier versions relied on codec packs (like K-Lite Codec Pack or Combined Community Codec Pack) to integrate ffmpeg (via ffdshow) and other additions into Windows' native DirectShow.
== See also == {{Portal|Free and open-source software}}
* Comparison of video container formats * List of open-source codecs * MKVToolNix * VLC media player * [https://lasergraphics.com/director.html#compression Motion picture film scanning output] to MKV wrapper for FFV1 and other formats.
== Notes == {{notelist}}
== References == {{reflist}}
== External links ==
* {{Official website}} * [https://www.loc.gov/preservation/digital/formats/fdd/fdd000342.shtml Matroska Multimedia Container] — Sustainability of Digital Formats: Planning for Library of Congress Collections
{{Compression formats}}
Category:Computer-related introductions in 2002 Category:Digital container formats Category:Free digital container formats Category:Open formats