Certain elements are commonly used in media-related metadata definitions. This section defines these common elements in the form of the "md" namespace.

Full documentation is a combination of the written document and the XML Schema itself.


This release adds features requested by implementers to suppor a broader range of use cases. This includes controlled vocabulary for codecs and file formats as well additional data types.

Version 2.10 Specification (December 28, 2021)

  • Common Metadata, TR-META-CM, v2.10, December 28, 2021 (PDF)
    • Version showing changes from v2.9 (PDF)

Version 2.10 Schema

A presentation summarizing Common Metadata, MEC, Media Manifest and MMC upddates can be found here (PDF)

VALIDATOR and Tool Suite

Information and links to the MDDF Validator are here: www.movielabs.com/md/validator.

The Tool Suite, including an online validator are at mddf.movielabs.com.

Best Practices

Guidance for solving specific problems on undertanding certain concepts can be found at www.movielabs.com/md/practices

Release History

A full release history including change lists and deprecated versions can be found here.


Educational Materials

We have created videos that explain concepts. An introduction to metadata can be found here. The full class is here. A video explaination of the Language Metadata Table is here.

Controlled Vocabularies




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