Near-realtime lossy compression of many PCM streams

Started by Iain Surgey August 1, 2010

I want to build a server that can compress many different PCM streams
simultaneously. This laptop can encode mp3 at 18x the speed of playback,
which theoretically means it could encode up to 18 different streams in
near-realtime (in reality this would probably be lower). With faster
hardware this would improve, perhaps to the region of 50 streams.

However I want to be able to handle much more than this, at least hundreds
per server, without very expensive hardware, and would like to know if this
is at all possible using custom hardware. Perhaps something like
programmable DSP chips, ASICs, FPGAs or other solutions if they help, but
before starting this project I thought I'd ask for the opinion of those more
experienced to determine if this is possible, and if so what would be the
best solution(s). What I'm after is the largest 'bang for my buck', so the
most audio streams per $ of hardware. I just don't want to sink loads of
time and money into this (though it would be a valuable educational
exercise) if it's not even feasible in the first place.

It doesn't necessarily have to be mp3, vorbis or AAC would be fine too.