Since MPEG-4 is a comprehensive multimedia standard, this category lists sites about several audio formats, all being part of MPEG-4 Audio. "Natural" coding of sound: Advanced Audio Coding (AAC, also its MPEG-2 version), TwinVQ (aka VQF), CELP, Parametric Codecs (HVXC, HILN). "Synthetic" coding of sound: Structured Audio Orchestra Language (SAOL) and Structured Audio Score Language (SASL), Text-To-Speech (TTS). The container format MP4 also belongs to this category, as long as it includes audio-only tracks with *.m4a, *.m4b or *.mp4 file extension and not video or other parts of the MPEG-4 standard like 2D/3D graphics. Due to the new developments in mobile communication the 3GPP/3GP2 standard and its audio codecs (several AMR and AAC variants) should be included here, also because their container formats *.3gp and *.3g2 are very similar to MP4, although not the same.
All available articles and documents from the Journal of Audio Engineering Society with search tool including a CD about coding artifacts.
Book by Mark Kahrs and Karlheinz Brandenburg.
ARL is a commercial laboratory involved in subjective quality assessment methods like preparing and analyzing codec comparisons for 3GPP.
DRM is a world-wide initiative to use analog AM radio for digital sound and services implementing aacPlus at very low bitrates, often mixed up with Digital Rights Management for copy protection.
Besides this forum for audio codecs there are others for container formats and video encoding in general with FAQs.
Many TTS demos in several languages from different systems with links to their homepages.
Forum about audio coding in general with two separate boards for AAC.
Publicly available standards from the International Organization for Standardization including MPEG-4 with 14496-5 containing the Audio, Visual and Systems parts.
Reading list for an MIT seminar, most of the mentioned publications are directly available on their web server or linked to Amazon's book section.
Hard- and software company for professional broadcasting products with AAC/MP4 support.
Reviews, articles and forum discussions about cell phones capable of AAC/MP4/3GP playback (also called "iTunes" format sometimes, use the site search).
John Lazarro and John Wawrzynek from the CS Division, UC Berkeley provide tutorials, downloads, manuals and links related to the Structured Audio format.
Book by Ken C. Pohlmann.
Apple offers technical FAQs, knowledge base and publicly available documentation files including the MOV file format.
List of internet radio stations using aacPlus for their low bitrate streams, among them SomaFM.com and Boomer Radio.
Patent pool administrator for AAC with FAQs and overviews of royalty fees for commercial implementations.
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