Alex Mogurenko`s Blog

Couple months ago I worked on audio conference project…
On first view everything looks pretty easy (what you need just capture video/audio compress it and send to destination + all encoders/decoders already implemented), but when firs beta was ready we found million underwater stones, even if my connection is fast enough it doesnt mean that connection same fast on the other side

so as solution we decided to encode audio with different bitrates (bitrate depends on receiver connection speed) seems might be ok, but its quite expensive to run 3 or more encoders in the same time even on desktop (and almost impossible on mobile platforms).. after couple weeks fighting with this problem i decided to go different way, the most expensive part of all MPEG audio encoders is Psycho acoustic  model, but it not much depends on destination bitrate… as result I did implement multi bitrate MPEG 1 Layer 2 audio encoder that can encode in up 10 different bitrates in the same time with cpu usage pretty similar to single bitrate encoder.

I was not surprised that it works pretty well on Desktop (Windows/Linux) and mobile platforms (Windows CE/Android)

this post is kinda announcement of new project that i start i`m sure that that kind of encoder will be pretty useful for audio conference software or for online radio stations for example

Filed under: Programming, Uncategorized