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 annual release of Common Metadata expands people and character descriptions, expands inclusive language to people’s titles/honorifics, and provides the means to capture trivia and other interesting facts. For technical data, Common Metadata eliminates ambiguities around timecodes, and masks.

Version 2.11 Specification (December 23, 2022)

  • Common Metadata, TR-META-CM, v2.11, December 23, 2022 (PDF)
  • Version showing changes from v2.10 (PDF)

Version 2.11 Schema

A presentation summarizing Common Metadata, MEC, Media Manifest and MMC updates 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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