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.


Version 2.8 adds new features as well as a variety of new types that are used across other specifications, especially the new Asset Ordering and Delivery specifications.

A presentation summarizing Common Metadata, MEC, Media Manifest and MMC updates can be found here (PDF). A list of changes can be found in the document and on the History page here.

Version 2.8 Specification

  • Common Metadata, TR-META-CM, v2.8, December 14, 2019 (PDF)
    • Version showing changes from v2.7 (PDF)

Version 2.8 Schema

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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