FAQ & White Papers


Answers to frequently asked questions

If you have further questions that are not answered here, please send an email to contact

What is the mission of this website?
This website seeks to provide information and support regarding MPEG AAC. The MPEG standardization process states that there is need for more practical guidance through the versatile world of MPEG AAC. This work is done by the MPEG Ad-hoc group on Responding to Industry Needs on Adoption of MPEG Audio

Who are the members of the AhG?
Currently a lot of well-known companies are working together in the Ad-hoc group (AhG). Some examples are listed here.

I want to know what is going on with the web site, is there a newsletter?
At the moment there is no newsletter, but if you are an MPEG member you can subscribe to our AhG email list. Please send an email to the chair of the AhG and he will add you.

How many devices have AAC licenses?
At the moment there are approximately seven billion AAC devices worldwide.

Which devices, platforms, etc. currently support MPEG AAC?

  • used in every mobile operating system (including Android and iOS)
  • natively supported in every leading operating system (including Windows and OSX), media player, and browser
  • used in all tablets and game consoles, in most DTVs, Blu-ray players, STBs and music players, and in most cars and digital radios

What is the patent and licensing situation?
Please see Info about licensing

How can I get access to the download area?
First you have to register (please send an email to contact), then you will get a login and password, and with that you can access the download area.

Do these tests guarantee conformance?
No, they are intended as informal tests to check implementations. MPEG has formal conformance streams available for complete testing.

What are the test items are supposed to sound like?
In the test packages there is always a reference WAV file, which should be downloaded for comparison.

I have designed my own test vectors and would like to share them. What should I do?
You can contact the MPEG AhG members via email (contact). They will check your input and discuss further steps.

What kind of support does MPEG provide for implementers of MPEG Audio?
MPEG offers support for conformance testing, which could be obtained via the ISO store. Enter 14496-26 into the search form and you will get an overview of the available standards.

Is there any reference software for MPEG AAC?
The MPEG AAC reference software can be obtained via the ISO store. For additional information, please see MPEG-4 Reference Software.

Who can I ask if I have a technical question regarding the mpeg standard?
Our website hosts a mailing list (aac-tech@mpeg-audio.org) that permits interested users to post questions that will be answered by experts.

Mpeg white papers

Literature and Links

  • The Moving Picture Experts Group website
  • DASH Industry Forum
  • MPEG web site (Working Group 11 of SC29)
  • Schnell, et al: "MPEG-4 Enhanced Low Delay AAC - a new standard for high quality communication", 125th AES Convention, 2008 Oct 2-5, San Francisco, USA (download pdf from AES)
  • Lutzky, et al: "AAC-ELD v2 - The new State of the Art in High Quality Communication Audio Coding", 131th AES Convention, 2011 Oct 20-23, NY, USA (download pdf from AES)
  • Engdegard, et al: "Spatial Audio Object Coding (SAOC) - the upcoming MPEG Standard on Parametric Object Based Audio Coding", 124th AES Convention, 2008 May 17-20, Amsterdam (download pdf from AES)
  • Karlheinz Brandenburg: "MP3 and AAC explained", AES 17th International Conference on High Quality Audio coding (download pdf from AES)
  • "Full-HD Voice: Understanding the AAC codecs behind a new era in communication" (EDN article)
  • Dynamic adaptive streaming over HTTP (DASH) — Part 3: Implementation guidelines ISO/IEC PDTR 23009-3 (Download zip archive)
  • Neuendorf, et al: "The ISO/MPEG Unified Speech and Audio Coding Standard – Consistent High Quality for all Content Types and at all Bit Rates", Journal AES, Vol. 61, No. 12, 2013 December (download pdf from AES)