MPEG-4 File Format, V.2, with Advanced Audio Coding

Table of Contents

Format Description Properties

Relationship to other formats
Full name	MPEG-4 Version 2 file format with Advanced Audio Coding
Description	MPEG-4 Version 2 file format containing AAC encoded data.
Production phase	Generally used for final-state, end-user delivery.
Subtype of	MP4_FF_2, MPEG-4 File Format, Version 2
May contain	AAC_MP4, Advanced Audio Coding, MPEG-4
May contain	AAC_MP4_LC, AAC (MPEG-4) Low Complexity Object
May contain	Additional audio, graphics, and scene graph stream types. Not documented at this time.

LC experience or existing holdings	None
LC preference	See the Library of Congress Recommended Formats Statement for format preferences for audio works.

Disclosure	See MP4_FF_2
Documentation	See MP4_FF_2 and AAC_MP4.
Adoption	See MP4_FF_2 and AAC_MP4.
Licensing and patents	See MP4_FF_2 and AAC_MP4.
Transparency	See AAC_MP4.
Self-documentation	See MP4_FF_2 and AAC_MP4.
External dependencies	See AAC_MP4.
Technical protection considerations	See MP4_FF_2.

Sound
Normal rendering	Good support.
Fidelity (high audio resolution)	See AAC_MP4.
Multiple channels	See AAC_MP4.
Support for user-defined sounds, samples, and patches	See AAC_MP4.
Functionality beyond normal rendering	See AAC_MP4.

Tag	Value	Note
Filename extension	See note.	See MP4_FF_2 and AAC_MP4.
Internet Media Type	See note.	See MP4_FF_2.

General
History

ISO/IEC 14496-1:2010 Information technology -- Coding of audio-visual objects -- Part 1: Systems
ISO/IEC 14496-3:2019 Information technology -- Coding of audio-visual objects -- Part 3: Audio
ISO/IEC 14496-12:2022 Information technology -- Coding of audio-visual objects -- Part 12: ISO base media file format
ISO/IEC 14496-14:2020 Information technology -- Coding of audio-visual objects -- Part 14: MP4 file format

URLs

MPEG-2/MPEG-4 AAC (http://www.mp3-tech.org/aac.html). From MP3-tech.org
"MP3 and AAC Explained" is a 1999 article by Karlheinz Brandenburg, Fraunhofer Institute, Erlangen, Germany. It has good detail but with a focus on AAC_MP2. It is available in several locations and at least two forms.
- MP3 and AAC Explained (as PDF) (https://www.iis.fraunhofer.de/content/dam/iis/de/doc/ame/conference/AES-17-Conference_mp3-and-AAC-explained_AES17.pdf). As published in proceedings of the 17th AES International Conference on High Quality Audio Coding, 1999, Sept 2-5.
- MP3 and AAC Explained (link via Internet Archive; transcribed to HTML) (https://web.archive.org/web/20210413042929/https://www.telosalliance.com/support/MP3-And-AAC-Explained). Transcription to HTML around 2013 indicates the article's classic status and continuing usefulness.
See MP4_FF_2 and AAC_MP4.

Last Updated: 05/01/2023

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