AS-11: Media Contribution File Formats

The AMWA AS-11 family of Specifications define constrained media file formats for the delivery of finished media assets to a broadcaster or publisher.  Each Specification is developed for a particular business purpose.


UHD program contribution for the DPP


AS-11 HD & SD DPP is well established for the delivery of finished programs to media companies within the UK.  But the future move to UHD has led to a new set of requirements from the Digital Production Partnership, leading to an AMWA specification called AS-11 X1.


AS-11 International Versions


Use of the AS-11 specification simplifies the process of creating and moving program material between post houses and playout companies – and the benefits are being recognized around the world.  New specifications for the delivery of finished programs have been created for use in the Nordic countries, Australia and New Zealand, building on the UK specifications.  These new Specifications are closely aligned and based on the new rules based format.

These are:

  • AS-11 X2 (HD Intra) created for adoption in Australia and New Zealand

  • AS-11 X3 (HD Long GOP at European frame rates) created for adoption in the Nordic Countries.

  • AS-11 X4 (HD Long GOP at U.S. frame rates) created for adoption in the Nordic Countries.

NABA DPP AS-11 Specifications for North America


The North American Broadcasters Association (NABA) and the Digital Production Partnership (DPP) have worked in partnership to develop two technical specifications for the delivery of air-ready HD television programs.  These specifications are designed for use in Canada and the United States and require that program files must conform to either AS-11 X8 (MPEG-2) or AS-11 X9 (AVC).


Rules based specifications


Traditionally, AMWA specifications have been text based.  While being easily human-readable, they do not support automated processes or allow the specification to be quickly and efficiently adapted for new users.  This has led to the development of rules based, machine readable specifications.  Building blocks, or rules for each of the video, audio (etc.) elements are combined into the final specification.  Human-readable descriptions can automatically be generated from the machine versions, and these blocks can be re-used in other specifications.  This new approach has proven especially valuable as AS-11 has been extended to accommodate the needs of new international users.

A new approach is also being taken to the publication of AS-11 Specifications.  Specifications are now being published on GitHub as "code" and move through different "maturity levels" from "Work In Progress", to "Specification".


Read an introduction to this new rules based approach to AMWA Specifications (PDF)

Technical Overview of AS-11 Specifications Design


Download an overview of the technical design of the AS-11 Specifications – includes a summary table of Specification properties

Additional AS-11 Resources


The AS-11 Overview GitHub project is used to host information on additional resources for all the AS-11 rules based Specifications including:

This AS-11 Wiki contains various resources including: