Material Exchange Format (MXF) is a container format for professional digital video and audio media defined by a set of

SMPTE The Society of Motion Picture and Television Engineers (SMPTE) (, rarely ), founded in 1916 as the Society of Motion Picture Engineers or SMPE, is a global professional association of engineers, technologists, and executives working in the m ...

standards. A typical example of its use is for delivering advertisements to TV stations and tapeless archiving of broadcast TV programs. It is also used as part of the

Digital Cinema Package A Digital Cinema Package (DCP) is a collection of digital files used to store and convey digital cinema (DC) audio, image, and data streams. The term was popularized by Digital Cinema Initiatives, LLC in its original recommendation for packaging ...

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 Essence ( la, essentia) is a polysemic term, used in philosophy and theology as a designation for the property or set of properties that make an entity or substance what it fundamentally is, and which it has by necessity, and without which it ...

", encoded in any of a variety of

video Video is an electronic medium for the recording, copying, playback, broadcasting, and display of moving visual media. Video was first developed for mechanical television systems, which were quickly replaced by cathode-ray tube (CRT) sy ...

and

audio compression format An audio coding format (or sometimes audio compression format) is a content representation format for storage or transmission of digital audio (such as in digital television, digital radio and in audio and video files). Examples of audio coding f ...

s, together with a

metadata Metadata is " data that provides information about other data", but not the content of the data, such as the text of a message or the image itself. There are many distinct types of metadata, including: * Descriptive metadata – the descriptive ...

wrapper which describes the material contained within the MXF

file File or filing may refer to: Mechanical tools and processes * File (tool), a tool used to ''remove'' fine amounts of material from a workpiece **Filing (metalworking), a material removal process in manufacturing ** Nail file, a tool used to gen ...

. Other "Operational Patterns" can contain or reference multiple materials, just like a simple timeline of a video editing program. MXF has full

timecode A timecode (alternatively, time code) is a sequence of numeric codes generated at regular intervals by a timing synchronization system. Timecode is used in video production, show control and other applications which require temporal coordinatio ...

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 Non-linear editing is a form of offline editing for audio, video, and image editing. In offline editing, the original content is not modified in the course of editing. In non-linear editing, edits are specified and modified by specialized sof ...

(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 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 AAF are now possible. Long-

GOP The Republican Party, also referred to as the GOP ("Grand Old Party"), is one of the two major contemporary political parties in the United States. The GOP was founded in 1854 by anti-slavery activists who opposed the Kansas–Nebraska Act, ...

MPEG-2 MPEG-2 (a.k.a. H.222/H.262 as was defined by the ITU) is a standard for "the generic coding of moving pictures and associated audio information". It describes a combination of lossy video compression and lossy audio data compression metho ...

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 Post-production is part of the process of filmmaking, video production, audio production, and photography. Post-production includes all stages of production occurring after principal photography or recording individual program segments. T ...

use. The two data-recording camera systems which produced MXF at that time,

Sony , commonly stylized as SONY, is a Japanese multinational conglomerate corporation headquartered in Minato, Tokyo, Japan. As a major technology company, it operates as one of the world's largest manufacturers of consumer and professional ...

XDCAM XDCAM is a series of products for digital recording using random access solid-state memory media, introduced by Sony in 2003. Four different product lines the XDCAM SD, XDCAM HD, XDCAM EX and XDCAM HD422 differ in types of en ...

and Panasonic's 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. Additionally, many MXF systems produce split-file A/V (video and audio stored in separate files), and use a file naming convention which relies on randomly generated filenames to link them. Not only does this exacerbate the issue of knowing exactly what is in an MXF file without specialized tools, but it breaks the functionality of standard desktop computer techniques. These techniques are generally used to manipulate data on a level as fundamental as moving, copying, renaming, and deleting. Using a randomly generated filename is uninformative to the user, but changing the name breaks the loose database structure between files. One example problem that caused interoperability problems in 2004 was when popular MXF export tools (i.e. the ones that are free or cost the least) would not allow the user to create a stereo AES file within the MXF wrapper, nor allow the user to add a free-text annotation to the MXF file so created (in order, for instance, that the next user of the file be able to interpret his or her intentions). Thus, an MXF file received and unwrapped may reveal SMPTE D10 compliant essence with eight ''mono'' AES audio components; the recipient has no way of knowing whether these components are multiple stereo pairs, 5.1 or serve some other purpose. Some of the incompatibilities were addressed and ratified in the 2009 version of the standard. MXF is used as the audio and video packaging format for

(DCP). It is also used in the

STANAG In NATO, a standardization agreement (STANAG, redundantly: STANAG agreement) defines processes, procedures, terms, and conditions for common military or technical procedures or equipment between the member countries of the alliance. Each NATO st ...

specification documents. 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 products that support the MXF standard: *

FFmpeg FFmpeg is a free and open-source software project consisting of a suite of libraries and programs for handling video, audio, and other multimedia files and streams. At its core is the command-line ffmpeg tool itself, designed for processing o ...

, an

open source Open source is source code that is made freely available for possible modification and redistribution. Products include permission to use the source code, design documents, or content of the product. The open-source model is a decentralized sof ...

project added support for muxing and demuxing of MXF and MXF D-10 in FFmpeg 0.5, released in March 2009. :* 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 se
ffmpeg trac ticket 5097
*

GStreamer GStreamer is a pipeline-based multimedia framework that links together a wide variety of media processing systems to complete complex workflows. For instance, GStreamer can be used to build a system that reads files in one format, processes them ...

is an open source Material Exchange Format (MXF) library.

Pitivi Pitivi (originally spelled PiTiVi) is a free and open-source non-linear video editor for Linux, developed by various contributors from free software community and the GNOME project, with support also available from Collabora. Pitivi is designe ...

uses this tool. * VSDC is a free video editor for open and edit mxf file. *

XMedia Recode XMedia Recode is a freeware video and audio transcoding program for Microsoft Windows developed by Sebastian Dörfler. It can import and export many types of files such as WMV, MP4, MP3, 3GP, Matroska and more. XMedia Recode can convert unprote ...

is a freeware converter tool that support MXF files. * Ingex is an open-source (

GPL The GNU General Public License (GNU GPL or simply GPL) is a series of widely used free software licenses that guarantee end users the four freedoms to run, study, share, and modify the software. The license was the first copyleft for general u ...

) suite of software for the digital capture of audio and video data, developed and heavily used by the BBC. SDI capture is supported, as well as real-time

transcoding Transcoding is the direct digital-to-digital conversion of one encoding to another, such as for video data files, audio files (e.g., MP3, WAV), or character encoding (e.g., UTF-8, ISO/IEC 8859). This is usually done in cases where a target de ...

(with MXF). Portions of the suite also act as a network file server for media files, as well as archiving to LTO-3 data tape.

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 The Moving Picture Experts Group (MPEG) is an alliance of working groups established jointly by ISO and IEC that sets standards for media coding, including compression coding of audio, video, graphics, and genomic data; and transmission and ...

essence data in MXF using the Generic Container) * SMPTE 383M: GC-DV (how to store 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 VBI Lines and Ancillary Data Packets * SMPTE RP210: SMPTE Metadata Dictionary (the latest version is availabl
here
) * SMPTE RP224: Registry of SMPTE Universal Labels

Availability of standards

SMPTE'
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 fro
SMPTEIRT Test Center
contains up-to-date information on the status of the SMPTE documents.

References

External links

MXF – a progress report
EBU Technical Review, 2010 Q3
MXF— a technical overview
EBU Technical Review, 2010 Q3 * https://web.archive.org/web/20050309043959/http://www.pro-mpeg.org/ Forum where MXF was initially discussed * http://www.amwa.tv/ Advance Media Workflow Association * https://web.archive.org/web/20121116052910/http://www.irt.de/mxf/ MXF Test Center * http://www.freemxf.org/ A multi-platform open source C++ library for reading and writing MXF files * (MIME type registration)
US Library of Congress Digital Preservation Program: MXF Format Description Properties
{{SMPTE standards Broadcasting standards Computer file formats Film and video technology SMPTE standards