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Old 30th June 2004, 09:50   #9  |  Link
tritical
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Join Date: Dec 2003
Location: MO, US
Posts: 999
Quote:
The temporal lock also happen to kill rainbows as a side-effect.
Actually, it is anything but a side-effect. GC works at filtering rainbows for the same reason it works on dot crawl... the method of filtering rainbows/dot crawl is exactly the same in stationary parts of the picture (where GC is suppose to work). For NTSC you average the pixels in the current frame with those 1 frame away which are exactly 180 degrees out of phase relative to the current frame (because of NTSC's 4 field color frame) and 2 frames away for PAL (PAL has an 8 field color frame). The reason GC tends to be more effective with filtering dot crawl is because "usually" the cross-luminance (dot crawl) oscillations tends to have less overall magnitude and tend to have somewhat more stable oscillation as compared to cross-chrominance (rainbowing) oscillations. That has a large impact on GC since it uses a max variation threshold and activation/recall settings.
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