skipper

I'm trying to make a live-editing environment in Jitter for 3 DV cameras. As Jitter cant't read multiple cameras in OSX I will be having to make it the Windows version with jit.dx.grab

The goal is to grab the video stream from 3 cameras and record those streams for future re-editing, as well as recording the 4th, 'edited' stream. I add a sound track from an external source (would love to record the sound as well, but can't use jit.dx.grab for the recording as I need the output from it)

The only problem is: I get framedrops as soon as I start recording a second camera.

Does anyone know where the bottleneck is? In theory, a computer should be able to record 3 DV streams simultaniously, if it doesnt try to decompress and if you attache each camera to a different PCIe-bus. But it doesnt seem to do it. I am running it on a Mac Pro Nehalem 4 core, with 6GB RAM and my CPUs run at about 15% capacity when I record. So... where is the bottleneck? And what can I do about it? Is it possible to buffer the videostreams for a couple of seconds to cut jitter some slack to decompress/compress? Can I record without decompressing/compressing? Can I use my GPU to help calculating? 

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Frame drop with multiple cameras