View source for Material Exchange Format

{{Short description|Video and audio media container format}}
{{Use dmy dates|date=August 2021}}
{{Infobox file format
| name                   = Material Exchange Format
| icon                   =
| logo                   =
| screenshot             =
| caption                =
| extension              = .mxf
| mime                   = application/mxf
| type code              = "mxf"
| uniform type           =
| magic                  =
| owner                  =
| released               = {{Start date and age|2004|09|22|df=yes}}
| latest release version = SMPTE ST 377-1:2019
| latest release date    = {{Start date and age|2020|01|28|df=yes}}
| type                   = [[Container format (digital)|Container format]]
| container for          = Audiovisual material, rich metadata
| contained by           =
| extended from          =
| extended to            =
| standard               =
| open                   = Yes
| free                   = Yes<ref>{{cite tech report |publisher=Library of Congress |location=Washington, D.C.  |series=Sustainability of Digital Formats |type=Full draft |title=Material Exchange Format (MXF) |date=17 January 2012 |url=https://www.loc.gov/preservation/digital/formats/fdd/fdd000013.shtml |access-date=13 December 2021}}</ref>
| url                    =
}}
'''Material Exchange Format''' ('''MXF''') is a [[Container format (digital)|container format]] for professional digital video and audio media defined by a set of [[SMPTE]] standards. A typical example of its use is for delivering advertisements to TV stations and tapeless archiving of broadcast TV programs.<ref>{{cite web |url=http://www.mediacom.dk/media/3339612/TV%202%20-%20Technical%20specifications.pdf |title=Technical Specifications – Commercial File Delivery |access-date=2016-12-14 |url-status=bot: unknown |archive-url=https://web.archive.org/web/20161220200906/http://www.mediacom.dk/media/3339612/TV%202%20-%20Technical%20specifications.pdf |archive-date=20 December 2016 }}</ref> It is also used as part of the [[Digital Cinema Package]] for delivering movies to commercial theaters.

== Summary ==
MXF, when used in the form of "Operational Pattern OP1A" or "OPAtom", can be used as a ''container'', ''wrapper'' or ''reference file'' format which supports a number of different streams of coded "[[essence (media)|essence]]", encoded in any of a variety of [[video compression format|video]] and [[audio compression format]]s, together with a [[Metadata (computing)|metadata]] wrapper which describes the material contained within the MXF [[computer file|file]]. Other "Operational Patterns" can contain or reference multiple materials, just like a simple timeline of a video editing program.

MXF has full [[timecode]] and metadata support and is intended as a platform-agnostic stable standard for future professional video and audio applications.

MXF was developed to carry a subset of the [[Advanced Authoring Format]] (AAF) data model, under a policy known as the [[Zero Divergence Directive]] (ZDD). This theoretically enables MXF/AAF workflows between [[Non-linear editing system|non-linear editing]] (NLE) systems using AAF and cameras, servers, and other devices using MXF.

== Usage ==
From 2004 onwards, MXF was in the process of evolving from standard to deployment. The breadth of the standard was subject to lead to interoperability problems, as vendors implement different parts of the standard or interpret misleading parts of the standard differently.

MXF is fairly effective at the interchange of [[SMPTE D10|D10]] (IMX) material, mainly because of the success of the Sony eVTR and Sony's eVTR RDD to SMPTE. Workflows combining the eVTR, Avid NLE systems, and broadcast servers using MXF in coordination with [[Advanced Authoring Format|AAF]] are now possible.

Long-[[Group of pictures|GOP]] [[MPEG-2]] material interchange between video servers is possible, as broadcasters develop application specifications they expect their vendors to implement.

As of autumn 2005, there were major interoperability problems with MXF in broadcast [[post-production]] use. The two data-recording camera systems which produced MXF at that time, [[Sony]]'s [[XDCAM]] and Panasonic's [[P2 (storage media)|DVCPRO P2]], produced mutually incompatible files due to opaque sub-format options obscured behind the MXF file extension. Without advanced tools, it was impossible to distinguish these incompatible formats.

Some of the incompatibilities were addressed and ratified in the 2009 version of the standard.<ref>{{cite web
 |url=http://tech.ebu.ch/docs/techreview/trev_2010-Q3_MXF-1.pdf
 |author=Pedro Ferreira
 |title=MXF – a progress report (2010)
 |date=23 July 2010
}}</ref>

MXF is used as the audio and video packaging format for [[Digital Cinema Package]] (DCP). It is also used in the [[STANAG]] specification documents.<ref name="stanag-spec">{{cite web |title=STANAG 4609 Edition 2 |url=http://www.nato.int/structur/AC/224/standard/4609/4609_documents/STANAG_4609_Ed2.pdf |archive-url=https://web.archive.org/web/20101110013520/https://www.nato.int/structur/AC/224/standard/4609/4609_documents/STANAG_4609_Ed2.pdf |archive-date=2010-11-10 |access-date=2010-08-18}}</ref>

The file extension for MXF files is ".mxf".  The Macintosh File Type Code registered with Apple for MXF files is "mxf ", including a trailing space.

== Tools ==

=== MXF converters ===
This list represents some examples of free and open source{{Why?|Why only free and open source ones if we're listing them.|date=October 2021}} products that support the MXF standard:

* [[FFmpeg]], an [[Open-source software|open source]] project added support for muxing and demuxing of MXF and MXF D-10 in FFmpeg 0.5, released in March 2009.<ref name="ffmpeg-changelog">{{cite web |url=http://www.ffmpeg.org/changelog.html |title=FFmpeg Changelog |date=2009-03-03 |access-date=2010-08-20}}</ref><ref name="ffmpeg">{{cite web |url=http://www.ffmpeg.org/ |title=FFmpeg |date=2008-12-03 |access-date=2010-08-20}}</ref>
:* Note that up to 2019, FFmpeg implements only the base MXF standard but does not provide vendor specific profiles, e.g. one cannot produce a MXF File that is compatible to Sony XDCAM devices due to missing header metadata entries (for further information see [https://trac.ffmpeg.org/ticket/5097 ffmpeg trac ticket 5097])
* [[GStreamer]] is an open source Material Exchange Format (MXF) library. [[Pitivi]] uses this tool.
* [[VSDC]] is a free video editor for open and edit mxf file.
* [[Ingex]] is an open-source ([[GPL]]) suite of software for the digital capture of audio and video data, developed and heavily used by the [[BBC]]. [[Serial digital interface|SDI]] capture is supported, as well as real-time [[transcoding]] (with MXF){{Dubious|reason=How does one "transcode" using a container?|date=October 2021}}. Portions of the suite also act as a network file server for media files, as well as archiving to [[Linear Tape-Open|LTO-3]] data tape.<ref name=ingex-sourceforge>{{cite web
| url = https://ingex.sourceforge.net/
| title = Ingex
| access-date=2009-08-24
}}</ref>

== The MXF standards ==

===Base documents===
* SMPTE 377M: The MXF File Format Specification (the overall master document)
* SMPTE EG41: MXF Engineering Guide (A guide explaining how to use MXF)
* SMPTE EG42: MXF Descriptive Metadata (A guide explaining how to use descriptive metadata in MXF)

===Operational patterns===
* SMPTE 390M: OP-Atom (a very simple and highly constrained layout for simple MXF files)
* SMPTE 378M: OP-1a (the layout options for a minimal simple MXF file)
* SMPTE 391M: OP-1b
* SMPTE 392M: OP-2a
* SMPTE 393M: OP-2b
* SMPTE 407M: OP-3a, OP-3b
* SMPTE 408M: OP-1c, OP-2c, OP-3c

===Generic containers===
* SMPTE 379M: Generic Container (the way that essence is stored in MXF files)
* SMPTE 381M: GC-MPEG (how to store [[MPEG]] essence data in MXF using the Generic Container)
* SMPTE 383M: GC-DV (how to store [[DV (video format)|DV]] essence data in MXF using the Generic Container)
* SMPTE 385M: GC-CP (how to store SDTI-CP essence data in MXF using the Generic Container)
* SMPTE 386M: GC-D10 (how to store [[SMPTE D10]] essence data in MXF using the Generic Container)
* SMPTE 387M: GC-D11 (how to store [[SMPTE D11]] essence data in MXF using the Generic Container)
* SMPTE 382M: GC-AESBWF (how to store [[AES/EBU]] and Broadcast Wave audio essence data in MXF using the Generic Container)
* SMPTE 384M: GC-UP (how to store Uncompressed Picture essence data in MXF using the Generic Container)
* SMPTE 388M: GC-AA (how to store A-law coded audio essence data in MXF using the Generic Container)
* SMPTE 389M: Generic Container Reverse Play System Element
* SMPTE 394M: System Item Scheme-1 for Generic Container
* SMPTE 405M: Elements and Individual Data Items for the GC SI Scheme 1

===Metadata, dictionaries and registries===
* SMPTE 380M: DMS1 (a standard set of descriptive metadata to use with MXF files)
* SMPTE 436M: MXF Mappings for [[Vertical blanking interval|VBI]] Lines and [[Ancillary data|Ancillary Data Packets]]
* SMPTE RP210: SMPTE Metadata Dictionary (the latest version is available [http://smpte-ra.org/smpte-metadata-registry here].)
* SMPTE RP224: Registry of SMPTE Universal Labels

== Availability of standards ==

SMPTE's [http://www.smpte.org/standards/ top standards page] has information, for the ordering of CD-ROMs, which would hold formal copy of the SMPTE standards. Judging by SMPTE's index, all of the standards, referenced above, would be contained on those CD-ROMs, as available from [http://www.smpte.org/ SMPTE].
[http://mxf.irt.de/information/specification/index.php IRT Test Center] {{Webarchive|url=https://web.archive.org/web/20101005012518/http://mxf.irt.de/information/specification/index.php |date=5 October 2010 }} contains up-to-date information on the status of the SMPTE documents.

== See also ==
* AAF, [[Advanced Authoring Format]]
* BXF, [[Broadcast Exchange Format]]
* [[Broadcast Wave Format|BWF]], Broadcast Wave Format
* DPX, [[Digital Picture Exchange]]

==References==
{{reflist}}

== External links ==
* [http://tech.ebu.ch/docs/techreview/trev_2010-Q3_MXF-1.pdf MXF – a progress report] EBU Technical Review, 2010 Q3
* [http://tech.ebu.ch/docs/techreview/trev_2010-Q3_MXF-2.pdf MXF— a technical overview] EBU Technical Review, 2010 Q3
* [https://web.archive.org/web/20050309043959/http://www.pro-mpeg.org/ Untitled Document] Forum where MXF was initially discussed
* [http://www.amwa.tv/ HOME] Advance Media Workflow Association
* [https://web.archive.org/web/20121116052910/http://www.irt.de/mxf/ mxf] MXF Test Center
* [http://www.freemxf.org/ freeMXF.org - MXF tools and information for free] A multi-platform open source C++ library for reading and writing MXF files
* {{IETF RFC|4539|link=no}} (MIME type registration)
* [https://lasergraphics.com/director.html#compression Motion picture film scanning output format] MXF wrapper ([[JPEG 2000]])
* [http://www.digitalpreservation.gov/formats/fdd/fdd000013.shtml US Library of Congress Digital Preservation Program: MXF Format Description Properties]

{{Compression formats}}
{{SMPTE standards}}

[[Category:Audiovisual introductions in 2004]]
[[Category:Computer-related introductions in 2004]]
[[Category:Broadcasting standards]]
[[Category:Computer file formats]]
[[Category:Film and video technology]]
[[Category:SMPTE standards]]