#169612 - RobinWatts - Sun Jul 26, 2009 7:27 pm
Hi all,
I touched on this in another thread, but thought it was probably worthy of announcing in a thread of it's own.
I've just put the finishing touches to a fast Siren14 decoder library that should work well on the NDS, called Siryn.
For those that don't know, Siren14 is a patented algorithm from Polycom (see http://www.polycom.com/company/about_us/technology/siren14_g7221c/index.html for details).
It offers "near CD quality" audio at low bitrates (24-48kbps), in a fraction of the CPU time taken by MP3 or Ogg Vorbis. It *does* require a license, but royalty free licenses can be had for free from Polycom under very reasonable terms (see the above link for details). I'd encourage anyone interested in using digital audio in their homebrew to check it out.
Siryn, my implementation of the decoder is detailed here: http://www.wss.co.uk/pinknoise/siryn
I haven't actually tested it on the NDS (I've been testing on a WinCE device), but it should run fine, and the low CPU usage (estimated as between 3.7 and 7.4MHz depending on bitrate etc) should allow for multiple simultaneous decodes/mixing etc on the ARM7.
If I ever get encoding working too (supposedly not much more complex than decoding), it could give interesting results with the microphone on the NDS; walkie talkie via WiFi anyone? :)
Robin
I touched on this in another thread, but thought it was probably worthy of announcing in a thread of it's own.
I've just put the finishing touches to a fast Siren14 decoder library that should work well on the NDS, called Siryn.
For those that don't know, Siren14 is a patented algorithm from Polycom (see http://www.polycom.com/company/about_us/technology/siren14_g7221c/index.html for details).
It offers "near CD quality" audio at low bitrates (24-48kbps), in a fraction of the CPU time taken by MP3 or Ogg Vorbis. It *does* require a license, but royalty free licenses can be had for free from Polycom under very reasonable terms (see the above link for details). I'd encourage anyone interested in using digital audio in their homebrew to check it out.
Siryn, my implementation of the decoder is detailed here: http://www.wss.co.uk/pinknoise/siryn
I haven't actually tested it on the NDS (I've been testing on a WinCE device), but it should run fine, and the low CPU usage (estimated as between 3.7 and 7.4MHz depending on bitrate etc) should allow for multiple simultaneous decodes/mixing etc on the ARM7.
If I ever get encoding working too (supposedly not much more complex than decoding), it could give interesting results with the microphone on the NDS; walkie talkie via WiFi anyone? :)
Robin