To get decent quality without getting the HUGE filesizes and processing times when using HUFFYUV, my way to go is the PicVideo MJPEG codec @ quality 19. I used to capture through AVI_IO, and I really have some noise because of this crappy WinTV PCI card (BTW: Hauppauge drivers, I never succeeded in using btwincap, only system crashes).
Somehow I have to get rid of the noise, because I want to encode to DivX5 with reasonable bitrate and good quality. With AVI_IO there's no option to filter the frames before the encoding step (MJPEG). Thus the noise will be encoded, which makes the overall quality worse, and which makes it even harder to get rid of the noise later.
Using VirtualDub VCR (the VirtualDub version with the recording timer, see
www.virtualdub.net) I switch on the noise reduction in the video menu (capture mode). This way I get rid of the noise BEFORE encoding to MJPEG, and I encoded films to DivX5 from this MJPEG source without further denoising (no spatial or temporal filters), and I got better quality than ever before!
There were no frame drops due to the extra denoising while capturing on my Athlon 1.3 GHz, Win2000.
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