I made a one-line change to audio-macosx.cc to increment the available bytes counter as each input byte is stored in the ring buffer instead of updating the available bytes all at once after all the bytes have been dumped into the ring buffer. This may or may not improve performance under Mac OS 10.1, but I hope it does. Perhaps the input buffer was really large so all this playing with memory was taking a while. But if it's the resampling and filtering that is causing the slowdown, then this isn't going to make much difference. In that case, I'll have to breakdown the resampling and ring buffer population into two or more iterations. That could be the solution. I've sent my changed file off to Claudio Allocchio and Denis DeLaRoca to see if they notice any improvement under Mac OS 10.1.5.

I also added a VDSetCompression call to video-macosx.cc to hopefully address the change in the IOXperts FireWire webcam driver. I've sent this to Claudio to try out, but also to Paolo Barbato because it might make the IOXperts' USB webcam driver work as well. Apple's API and abstraction is very nice, in that I don't even have to care what's hooked up because everything uses a Video Digitizer. I just have to make sure my API calls are correct. If this change doesn't fix things, I'll have to ask on the IOXperts' beta discussion lists.

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