Difference between revisions of "Advanced Audio Coding"

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(Add to formats missing in FFmpeg category.)
(Move AAC+ info from wishlist)
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See also [[Understanding AAC]].
See also [[Understanding AAC]].
=== Extensions ===
== AAC+ ==
[http://www.codingtechnologies.com/products/aacPlus.htm AACPlus] (a.k.a. AAC+) is HE-AAC + [http://www.codingtechnologies.com/products/sbr.htm SBR (Spectral Band Replication)] and aacPlus v2 means HE-AAC + [http://www.codingtechnologies.com/products/sbr.htm SBR (Spectral Band Replication)] + [http://www.codingtechnologies.com/products/paraSter.htm PS (Parametric Stereo)]. Standard HE-AAC decoders can decode aacPlus encoded files/streams but without [http://www.codingtechnologies.com/products/sbr.htm SBR] and [http://www.codingtechnologies.com/products/paraSter.htm PS] you do not get the full quality.
* See also
** [[MP3#mp3PRO|MP3PRO]] that also uses SBR.
** [http://www.mpegsurround.com MPEG Surround] that can used for all audio but especially MP3/mp3PRO and AAC/aacPlus. [http://www.codingtechnologies.com/products/mpgsrnd.htm MPEG Surround technology] share similar characteristics with [http://www.codingtechnologies.com/products/sbr.htm SBR (Spectral Band Replication)] and [http://www.codingtechnologies.com/products/paraSter.htm PS (Parametric Stereo)], which [[MP3#mp3PRO|MP3PRO]] and AAC+ decoders also use. [http://www.divx.com DivX Inc.] is one company that uses MPEG Surround technology to achieve 5.1 channel surround sound in smaller files.


[[Category:Audio Codecs]]
[[Category:Audio Codecs]]
[[Category: MDCT Audio Codecs]]
[[Category: MDCT Audio Codecs]]
[[Category: Formats missing in FFmpeg]]
[[Category: Formats missing in FFmpeg]]

Revision as of 05:26, 6 October 2007

  • FOURCCS: ????
  • Company: ISO

Specification and reference source links. http://www.3gpp.org/ftp/specs/html-info/26-series.htm ftp://ftp.tnt.uni-hannover.de/pub/MPEG/audio/mpeg4/

Intel has source for its IPP based AAC decoder: http://www.intel.com/cd/software/products/asmo-na/eng/perflib/ipp/219611.htm?prn=y

Real Networks has source for its Helix AAC fixedpoint decoder here: https://datatype.helixcommunity.org/2005/aacfixptdec

Usually stored in an MP4 container.

See also Understanding AAC.

Extensions

AAC+

AACPlus (a.k.a. AAC+) is HE-AAC + SBR (Spectral Band Replication) and aacPlus v2 means HE-AAC + SBR (Spectral Band Replication) + PS (Parametric Stereo). Standard HE-AAC decoders can decode aacPlus encoded files/streams but without SBR and PS you do not get the full quality.