Opus audio encoding on NRF52840

[Kr4m4]

Hi, I'm new here so please let me know if any additional information could help.

We are in need of encoding speech on a nRF52840 and are working in Opus and are having trouble making it fit in our compute budget. Browsing on here I've seen similar questions but I wasn't completely clear on a few things that I was hoping someone could answer.

Am I correct in that I've read that the nRFready Smart Remote 3 for nRF52 Series comes with an implementation of Opus that is optimized for nRF52? If so, does it require less overall compute? If that's the case, do we need to just buy the Smart Remote 3 DK in order to access this nRF52 optimized version of Opus?

Thanks for your help!

[Joakim Jakobsen]

Hi. 

Yes, we have a software implementation of Opus compression in our Smart Remote 3 reference design, but this does not use decompression. Note that compressing/decompressing audio in real-time in software can be very CPU demanding, especially with higher bitrates.

You can download the FW here: http://www.nordicsemi.com/eng/Products/Bluetooth-low-energy/nRFready-Smart-Remote-3-for-nRF52-Series#Downloads  You do not need to buy the Smart Remote to download the FW.

More information can be found in these previous threads: 
https://devzone.nordicsemi.com/f/nordic-q-a/33414/opus-decoder
https://devzone.nordicsemi.com/f/nordic-q-a/35646/sr3-52-fw-v1-2-opus-migrate-and-anr/137725#137725 
https://devzone.nordicsemi.com/f/nordic-q-a/48219/for-opus-applications-is-an-audio-dac-chip-required 

Best regards, 
Joakim