Low Pass Filters
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Low-pass filters take out rapidly changing details in your image. As noise
is rapidly changing, the effect is to suppress noise but with a loss of
detail. The two low-pass filters implemented by JIMSAIP are Average and
Blur. The Average function, which is stonger than the Blur function,
replaces each pixel value with the average of itself combined with its 8
nearest neighbors. The Blur function replaces each pixel value with the
average of itself and its 5 closest neighbors. The result of either
operation is in the B buffer and the values in the A buffer remain
unchanged.
See the high-pass filter functions Crispen and
Sharpen for another effect.
