Quote:
Originally Posted by StainlessS
may keep this chromaweight of 0.333 (What I 'feel' is about right).
EDIT: I think I'm correct about most filters using a weighting of about 0.5 for combined chroma, dont myself think
this is a good measure, luma commonly fills it's full dynamic range, whereas chroma huddles about the middle,
as chroma habitually occupies considerably less dynamic range, it should count for less in any kind of weighting, even
if combining two chroma channels. If the dynmic range of chroma is somewhat reduced, then the difference between
two identical frames where one has been downsized/compressed has got to be likewise reduced and of lesser importance
as a measure. Think about 33% might be a better guestimate.
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Seems the reason that combined chroma normally counts for 0.5 total weight can be found here:
http://forum.doom9.org/showthread.ph...032#post640032
And as already stated, chroma tends to huddle around the centre so should probably be of lesser weight.