Material Exchange Format
The Material Exchange Format ( MXF ) is an open (non- proprietary ) file format for video files from the broadcasting sector. It is a subset of the Advanced Authoring Format (AAF) and was defined with the aim of simplifying the exchange of audio-visual files (including metadata ).
General
It is an envelope format, also known as a wrapper format or container format , which encapsulates and accurately describes one or more essences (also known as pay load ). These essences can be images, sound or data. An MXF file contains enough information to allow two applications to exchange essences without first exchanging information. For this purpose it contains so-called metadata, which z. B. provide information about the length of the file, the codecs used ( compression method ) and timeline complexity.
In contrast to tape-based video formats ( MAZ technology), the MXF definition is intended to simplify the file-based handling of professional video formats. By standardizing the way to IT-based to non-linear video editing (NLE) be accelerated without going through mixed and manufacturer-specific (proprietary) data formats to be hindered.
The standard was promoted by the SMPTE , the European Broadcasting Union (EBU) and the Advanced Authoring Format (AAF) Association and passed in 2003 under the standard designation SMPTE 377M. The file format is proposed as the ISO standard.
Sony and Panasonic , in particular, rely entirely on this standard with their broadcast technologies ( IMX and XDCAM technology at Sony, DVCPro at Panasonic), which have already been widely used in practice, and have ensured widespread use since 2003.
The MXF Basis Standard SMPTE 377M, initial version, was finally finalized in 2004 and revised again in 2009 and 2011, mainly to correct inconsistencies.
Operational patterns
MXF containers can hold data of almost any complexity. Operational patterns were introduced to enable programs to estimate their complexity in advance. The operational patterns give a rough overview of the cutting list ( EDL ) and the division into different essence packages (source pack or file pack). The operational patterns do not describe the type of compression or the number of tracks (exception: OP atom).
Originally nine operational patterns were introduced. These patterns are identified with numbers from 1-3 and letters from ac. The numbers give information about the cutting list ( EDL ), while the letters give information about the division into different essence packs (source pack or file pack).
The operational pattern OP-Atom was added later. In contrast to the other operational patterns, the OP atom contains only a single essence and was introduced to generate a simple MXF file.
Standardization of the individual operational patterns:
- OP1a: SMPTE 378M
- OP1b: SMPTE 391M
- OP1c: SMPTE 408M
- OP2a: SMPTE 392M
- OP2b: SMPTE 393M
- OP2c: SMPTE 408M
- OP3a: SMPTE 407M
- OP3b: SMPTE 407M
- OP3c: SMPTE 408M
- OP atom: SMPTE 390M
MXF in practice
Almost all manufacturers of professional software in the broadcast sector have adapted the MXF format. The public broadcasters in the DACH region exchange information with one another in the MXF-OP1A format and also use it internally for the most part as a production and archiving format. The use of the MXF format is by no means limited to the DACH region. It is now very widespread in television stations around the world.
There are still various problems when exchanging MXF formats between different systems within a broadcaster.
Various manufacturers sell products that are created solely for the purpose of finding compatibility problems in MXF formats.