Skype has recently published a highly optmized SILK implementation under a BSD like license as well as now provides a SILK PATENT LICENSE in order to use it. Silk is an audio codec mainly used for skype-to-skype calls.
SILK has been recently added in the amsip SDK on all platforms. It’s particularly interesting for usage on mobile devices (android/ios/…) where arm optimizations are highly wanted!
SILK, like OPUS, provides briliant alternative to compete with codecs like ARM and ARM-WB.