Advanced Audio Coding
- FourCC: AAC AACP MP4A mp4a VLB
- Company: ISO
- Samples: http://samples.mplayerhq.hu/A-codecs/AAC/
- Samples: sample repo at standards.iso.org
- Sample Docs: sample docs
Specification and reference source links.
- AAC Reference Software
Google has opensourced Android, which includes an Apache 2.0 licensed aac decoder:
Real Networks has source for its Helix AAC fixedpoint decoder here:
Usually stored in an MP4 container.
See also Understanding AAC.
HE-AAC (also known as by the Dolby trade name aacPlus) is AAC-LC + SBR (Spectral Band Replication) and HE-AAC v2 (aacPlus v2) is LC-AAC + SBR + PS (Parametric Stereo). Standard AAC-LC decoders can decode HE-AAC encoded files/streams but without SBR and PS you do not get the full quality.
- See also
- MP3PRO that also uses SBR.
- MPEG Surround that can used for all audio but especially MP3/mp3PRO and AAC/aacPlus. MPEG Surround technology share similar characteristics with SBR (Spectral Band Replication) and PS (Parametric Stereo), which MP3PRO and AAC+ decoders also use. DivX Inc. is one company that uses MPEG Surround technology to achieve 5.1 channel surround sound in smaller files.