High-Efficiency Advanced Audio Coding

High-Efficiency Advanced Audio Coding
Filename extensionsMPEG/3GPP Container

Apple Container

  • .m4a, .m4b, .m4p, .m4r, .m4v

ADTS Stream - NOT raw - Contains Headers

  • .aac
Internet media typeaudio/aac
audio/aacp
audio/3gpp
audio/3gpp2
audio/mp4
Developed byISO
Type of formatAudio compression format
Contained byMPEG-4 Part 14, 3GP and 3G2, ISO base media file format, Audio Data Interchange Format (ADIF), Audio Data Transport Stream (ADTS)
Extended fromAAC
StandardISO/IEC 14496-3
Hierarchical structure of AAC profile, HE-AAC profile and HE-AAC v2 profile, and compatibility between them. The HE-AAC profile decoder is fully capable of decoding any AAC profile stream. Similarly, The HE-AAC v2 decoder can handle all HE-AAC profile streams as well as all AAC profile streams. Based on the MPEG-4 Part 3 technical specification.[1]
Evolution from MPEG-2 AAC-LC (Low Complexity) Profile and MPEG-4 AAC-LC Object Type to HE-AAC v2 Profile.[2]

High-Efficiency Advanced Audio Coding (HE-AAC) is an audio coding format for lossy data compression of digital audio defined as an MPEG-4 Audio profile in ISO/IEC 14496–3. It is an extension of Low Complexity AAC (AAC-LC) optimized for low-bitrate applications such as streaming audio. The usage profile HE-AAC v1 uses spectral band replication (SBR) to enhance the modified discrete cosine transform (MDCT) compression efficiency in the frequency domain.[3] The usage profile HE-AAC v2 couples SBR with Parametric Stereo (PS) to further enhance the compression efficiency of stereo signals.

HE-AAC is used in digital radio standards like HD Radio,[4] DAB+ and Digital Radio Mondiale.

  1. ^ ISO/IEC JTC1/SC29/WG11/N7016 (2005-01-11), Text of ISO/IEC 14496-3:2001/FPDAM 4, Audio Lossless Coding (ALS), new audio profiles and BSAC extensions, archived from the original (DOC) on 2014-05-12, retrieved 2009-10-09{{citation}}: CS1 maint: numeric names: authors list (link)
  2. ^ Fraunhofer IIS, MPEG-4 Audio and Video Technology (PDF), retrieved 2009-10-15[dead link]
  3. ^ Herre, J.; Dietz, M. (2008). "MPEG-4 high-efficiency AAC coding [Standards in a Nutshell]". IEEE Signal Processing Magazine. 25 (3): 137–142. Bibcode:2008ISPM...25..137H. doi:10.1109/MSP.2008.918684.
  4. ^ "Receiving NRSC-5". theori.io. 9 June 2017. Archived from the original on 20 August 2017. Retrieved 14 April 2018.