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Most Firewire (DV) devices do not provide a VFW driver, and thus cannot be used by VirtualDub at all. VirtualDub needs a Video for Windows capture driver to capture. VirtualDub says I don't have a capture device, but I know I have one. You will take a sizeable hit with a 24-bit or 32-bit desktop if you have Preview on. Note that these are with a 16-bit desktop.
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Pentium III 733, Hauppauge WinTV, 44KHz 16-bit stereo PCM, 640x480 YUY2 at 29.97 fps compressed with Huffyuv in Predict Median, Preview on.Celeron 300 450, Hauppauge WinTV, 44KHz 16-bit stereo PCM, 640x480 YUY2 at 29.97 fps compressed with PicVideo at quality 18, on-screen display disabled.
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This is a hard question to answer, but I can tell you what I've been able to do: VirtualDub documentation: Capture Video capture in Windows is hardly a walk in the park, so here's a few tips to keep you going.
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