I’ve been spending a lot of my time over the last few months experimenting with audio/video compression for portable devices: trying to push the limits of quality. Its the ultimate exercise in tradeoffs.

We’ve looked at just about every compression tool out there, and have settled on Sorenson Squeeze as a great tradeoff between functionality and output quality (though for most applications it is simply a control panel for others’ codecs.) It lets us batch easily.

Even when bandwidth problems go away because you’re not streaming in real time (because most portable devices are playing back from a stored stream that was previously downloaded and synced), you run headlong into CPUs that can’t handle high stream rates, or can’t decompress a high stream rate while simultaneously throwing the pixels at the little screen.

The way this has been handled by Microsoft (under its “plays for sure” marketing program) is to dumb down the maximum stream rates and image sizes. The wmv specifications on my Archos AV700 mandate a size and stream rate (352×288@30fps 800kb/s) that is butt ugly on its 480×234 display. I’m finding, however, that you can push the envelope pretty far.

I’ve coded a theme statement/promo from an upcoming walkie-lookie series at what is (for web video) an insane rate:

• 160 kpbs audio data rate at 48k
  
• 1600 kpbs video data rate (with a 2400 kpbs cap)
  

It plays fine on my Archos, and I’m curious if it succeeds or fails on other wmv devices. Please let me know if it plays or croaks, either in the comments here or in email to beta@walkie-lookie.com.