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, and is identified using a new naming convention (AS-11 X), as designated below.


AS-11 is growing and maturing


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. These are described in 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 success of the “AS-11 DPP” specifications for the UK. These new Specifications are closely aligned and based on the new rules based format.

These are:

  • AS-11 X2 (HD Intra) initially to be adopted in Australia and New Zealand

  • AS-11 X3 (HD Long GOP at European frame rates) initially to be adopted in the Nordic Countries.

  • AS-11 X4 (HD Long GOP at U.S. frame rates) initially to be adopted 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: