Unified Speech and Audio Coding
Unified Speech and Audio Coding (USAC) is an
It uses time-domain linear prediction and residual coding tools (
Extended HE-AAC
The MPEG-D USAC standard (ISO/IEC 23003-3) defines the Extended High Efficiency AAC profile, which contains all of the tools of the
xHE-AAC
Fraunhofer has defined the xHE-AAC codec as the combination of the Extended High Efficiency AAC profile and appropriate parts of the MPEG-D DRC Loudness Control Profile or Dynamic Range Control Profile.
While xHE-AAC decoders will be able to decode the bit streams created for the previous AAC family profiles, xHE-AAC encoders are typically intended for encoding of MPEG-D USAC audio object type (AOT 42) with MPEG-D DRC loudness metadata, though some may support encoding legacy AAC object types.[7]
xHE-AAC is a mandatory audio codec in the Digital Radio Mondiale standard[9][10][11] and is a trademark of Fraunhofer.[7]
In April 2016, Via Licensing announced the launch of a xHE-AAC patent pool licensing program for 2016.[12] In 2018, xHE-AAC was included in Via Licensing's AAC patent pool at no additional cost.[8][13]
In January 2021, Fraunhofer announced a test service and trademark program for xHE-AAC and announced that the codec is being used by Netflix.[14][15] Netflix reported that users switched from speakers to headphones 16% less often (due to poor sound quality or inadequate volume) on high dynamic range content when using xHE-AAC instead of HE-AAC. Netflix also explained that xHE-AAC allowed them to begin streaming with adaptive audio bitrates to Android devices.[16] Fraunhofer also announced xHE-AAC licenses to MainConcept,[17] Poikosoft,[18] and LG.[19] xHE-AAC is supported by the Bento4 DASH/HLS packager.[20] In January 2022, MainConcept established a web encoding service to test xHE-AAC. In October 2022, xHE-AAC decoding was added to Windows 11 and Xbox devices.[21]
Compatibility
xHE-AAC is supported in Android since Android Pie[8] and in iOS since iOS 13. It has been announced that it will be added to watchOS 7[22][23] and has been licensed to Microsoft.[24] Playing xHE-AAC audio files is supported in foobar2000 with the use of an add-on AAC decoder.[25] In October 2022, Windows 11 added support for xHE-AAC in the 22H2 update.[26]
See also
- Opus (codec)– a royalty free alternative, low latency codec for a similar usage
References
- ^ MPEG. "Unified Speech and Audio Coding". The Moving Pictures Experts Group. Retrieved 2016-11-11.
- ^ "ISO/IEC DIS 23003-3 - Information technology -- MPEG audio technologies -- Part 3: Unified speech and audio coding". 2011-02-15. Retrieved 2011-07-18.
- ^ "ISO/IEC 14496-3:2009/PDAM 3 - Transport of unified speech and audio coding (USAC)". 2011-06-30. Retrieved 2011-07-18.
- ^ Neuendorf; et al. (2013-12-20), The ISO/MPEG Unified Speech and Audio Coding Standard—Consistent High Quality for All Content Types and at All Bit Rates, retrieved 2015-06-13
- ^ Neuendorf; et al. (2012-04-26), MPEG Unified Speech and Audio Coding-The ISO/MPEG standard for high-efficiency audio coding of all content types, retrieved 2015-06-13
- ^
Neuendorf, Max; Multrus, Markus; Rettelbach, Nikolaus; Fuchs, Guillaume; Robilliard, Julien; Lecomte, Jérémie; Wilde, Stephan; Bayer, Stefan; Disch, Sascha; Helmrich, Christian; Lefebvre, Roch; Gournay, Philippe; Bessette, Bruno; Lapierre, Jimmy; Kjörling, Kristofer; Purnhagen, Heiko; Villemoes, Lars; Oomen, Werner; Schuijers, Erik; Kikuiri, Kei; Chinen, Toru; Norimatsu, Takeshi; Chong, Kok Seng; Oh, Eunmi; Kim, Miyoung; Quackenbush, Schuyler; Grill, Bernhard (2013-12-01). "The ISO/MPEG Unified Speech and Audio Coding Standard - Consistent High Quality for all Content Types and at all Bit Rates". Journal of the Audio Engineering Society. 61 (12): 956–977. ISSN 0004-7554.
- ^ a b c "The xHE-AAC Trademark Program". Fraunhofer Institute for Integrated Circuits IIS. Retrieved 2021-02-11.
- ^ a b c "Fraunhofer's xHE-AAC Audio Codec Software Extends Native AAC Support In Android P For Better Quality At Low Bitrates". Fraunhofer Institute for Integrated Circuits IIS. Retrieved 2020-07-11.
- ^ "Technical Info | Digital Radio Mondiale". www.drm.org. Retrieved 2016-08-02.
- ^ "xHE-AAC". Fraunhofer Institute for Integrated Circuits IIS. Retrieved 2016-08-02.
- ^ xHE-AAC in Digital Radio Mondiale (DRM) (PDF). Fraunhofer IIS. 2015.
- ^ "Via Licensing Announces Extended High Efficiency AAC Patent Pool - Via Corp". www.via-corp.com. Retrieved 2016-08-02.
- ^ "Via Adds MPEG-D DRC To Advanced Audio Coding Patent Pool – ViaCorp". Retrieved 2020-07-11.
- ^ "Fraunhofer IIS Introduces New Test Service and Trademark Program for xHE-AAC Audio Codec". www.businesswire.com. 2021-01-12. Retrieved 2021-01-13.
- ^ "Netflix Now Streaming with Fraunhofer's xHE-AAC Audio on Android Mobile". www.businesswire.com. 2021-01-12. Retrieved 2021-01-13.
- ^ Blog, Netflix Technology (2021-01-21). "Optimizing the Aural Experience on Android Devices with xHE-AAC". Medium. Retrieved 2021-01-26.
- ^ "MainConcept launches xHE-AAC FFmpeg Encoder Plugin based on audio codec software from Fraunhofer – Fraunhofer Audio Blog". Retrieved 2021-10-06.
- ^ "Poikosoft's EZ CD Audio Converter now supports xHE-AAC Audio Codec from Fraunhofer IIS – Fraunhofer Audio Blog". Retrieved 2021-10-06.
- ^ "LG Electronics licenses xHE-AAC and AAC-ELD audio codec software from Fraunhofer IIS – Fraunhofer Audio Blog". Retrieved 2021-10-06.
- ^ "xHE-AAC audio codec supported by Bento4 DASH/HLS Packager – Fraunhofer Audio Blog". Retrieved 2021-10-06.
- ^ "xHE-AAC Audio Codec now in Windows 11 – Fraunhofer Audio Blog". Retrieved 2022-10-20.
- ^ "Apple recommends xHE-AAC for streaming of all audio assets – Fraunhofer Audio Blog". Retrieved 2020-07-11.
- ^ "What's new in streaming audio for Apple Watch - WWDC 2020 - Videos". Apple Developer. Retrieved 2020-07-11.
- ^ "Fraunhofer IIS licenses xHE-AAC audio codec software to Microsoft – Fraunhofer Audio Blog". Retrieved 2020-07-11.
- ^ kode54. "fdk-aac packet decoder". Retrieved 2020-12-14.
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: CS1 maint: numeric names: authors list (link) - ^ "xHE-AAC Audio Codec now in Windows 11". 2022-10-20. Retrieved 2024-04-20.