Quote:
Originally Posted by IanB
GaussResize at it's sharpest P setting is a PointResize.
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Thinking more about this, it's not always true and depends on resize ratio and where the resampling points fall.
Certainly, with P=100, the Gaussian kernel falls off so steeply that in many cases only the nearest pixel will have a non-zero weight, which I think is the basis of Ian's assertion.
However, if a resampling point is halfway between two pixels,
both neighbouring pixels will have equal weights (and if it's close to halfway, they will both still be non-zero and close to equal).
Thus, for example,
GaussResize(2*width, 2*height, 0.25, 0.25, P=100)
gives identical results to
BilinearResize(2*width, 2*height, 0.25, 0.25)
for RGB clips and the luma of YUV clips. (For YUV chroma, the offsets need to be 0.5).
(D-Dave, sorry for this technical hair-splitting which is really tangential to your original question.
)