Mxf

Que savons nous du MXF ?

KOIKESSE?

kelkun peut nous éclairer ?

 

Le MXF (materiel exchange format) est un format d'encapsulage. En gros c'est une enveloppe commune permettant la transmission de données audio, vidéo et également des meta data.

Les meta data sont des données texte pouvant être stockées en parallèle avec les données classiques et apportant des indications de lieu, de découpage... ou toutes autres données ayant été autorisés par le constructeur.

 

De la doc en anglais :

Extrait du pdf de Snell &Wilocx écrit par Bruce Devlin

What is MXF?

The Material eXchange Format (MXF) is an open file format targeted at the interchange of audio-visual material with associated data and metadata. It has been designed and implemented with the aim of improving file based interoperability between servers, workstations and other content creation devices. These improvements should result in improved workflows and result in more efficient working than is possible with today's mixed and proprietary file formats. MXF has been designed by the leading players in the broadcast industry with an enormous amount of input from the user community to ensure that the format really meets their demands. It is being put forward as an Open Standard which means it is a file transfer format openly available to all interested parties. It is not compression-scheme specific and simplifies the integration of systems using MPEG and DV as well as future, as yet unspecified, compression strategies. This means the transportation of these different files will be independent of content, not dictating the use of specific manufacturers’ equipment. Any required processing can simply be achieved by automatically invoking the appropriate hardware or software codec. However, MXF is designed for operational use and so all handling processes are seamless to the user. It just works. Besides offering better interoperability - working with video and audio between different equipment and different applications - the other major contribution is the transport of metadata. By developing MXF from the beginning as a new file format, considerable thought has gone into the implementation and use of metadata. Not only is this important for the proper functioning of MXF files, it will also enable powerful new tools for media management as well as improving content creation workflows by eliminating repetitive metadata reentry. The changing technology of television production and digital services to viewers means the ways for moving content – programme video and audio – in studios is changing too. Not only is there far greater use of computers and IT-related products, such as servers, but also reliance on automation and the re-use of material have expanded. Besides the need to carry metadata, file transfers are needed to fit with computer operations and streamed for real-time operations.

 

Même source :

METADATA
Also referred to as ‘data about data’ it exists in any system today. For example, timecode is a form of metadata. The problem is that, due to incompatibilities, this information is currently lost as the content moves between systems. MXF-enabled systems will communicate using metadata, video and audio. MXF metadata may carry information about:
The file structure The body contents – e.g. MPEG or DV, 525 or 625, etc
Key words or titles Subtitles Reference numbers Editing notes Location, time, date and version number
The list may be endless. In extreme cases files may contain more metadata than video or audio content! However, the efficient implementation of metadata is seen as the key to material management. The metadata may be filtered to hold only what is relevant to the particular operational environment, thereby cutting possible meta-mountains

 

thank you for such a timely answer.

 

you're welcome

 

Salut,
MXF est une norme de transmission de media de type Rush ou produits finis. C'est à dire que tu ne peux pas utiliser MXF pour transporter des séquences de montage comprenant des informations de type fondus, PiP, key etc....

En terme de séquence le MXF peux suelement transporter les media et des informations de CUT/trim et layers (plusieurs pistes vidéo et/ou audio).

C pour ça que l'on voit arriver des camescopes MXF et des videoSerer MXF puisque ces outils traitent des media de type "plats" c'est à dire sans d'info de séquences complexes.

Tout ça en opposition à AAF et OMF qui eux te permettent de transporter les informations de séquences complexes.