Rockbox General > Rockbox General Discussion

xHE-AAC support?


I searched these forums but didn't find a single post about xHE-AAC audio codec support. Currently rockbox doesn't support this codec however this codec has started to see larger usage over the past 4yrs since a patent pool was formed.

Earlier this year Audible signed a licensing deal to licence the codec ( so it looks like audible audiobooks will be switching from M4B audiobooks with the proprietary .AAX extension which has an encrypted key to xHE-AAC fairly soon.

xHE-AAC has been included in Android 9+, iOS 13+, macOS 10.15+ and windows 11.

Over the past couple of years netflix, instagram, facebook and others have been adopting it, partly due to better compression than opus at lower bitrates but quite a few blog posts talk about loudness control too (MPEG-D DRC).

Are any of you guys planning on adding support for xHE-AAC as people likely won't be able to listen to audible audiobooks anymore on rockbox unless they re-encode it to a different codec whereas currently they can strip the drm from their .AAX audible files and play them on rockbox with re-encoding.

ISO/IEC 23003-3 and ISO/IEC 23003-4 are the specs for this codec, it was ratified all the way back in 2012 but only when the patent pool formed in 2019 did it start to slowly catch on. Also it is free of charge for companies that already licence AAC variants: . They used to charge a separate amount for the xhe-aac codec which was quite expensive but no-one was licencing it so they decided to include it for free with the license all the other AAC variants.


[0] Message Index

Go to full version