More on filters…
Cross-correlation/convolution is useful for, e.g.,
w Blurring
w Sharpening
w Edge Detection
w Interpolation
Convolution has a number of nice properties
w Commutative, associative
w Convolution corresponds to product in the
Fourier domain
More sophisticated filtering techniques can often
yield superior results for these and other tasks:
w Polynomial (e.g., bicubic) filters
w Steerable filters
w Median filters
w Bilateral Filters
w
(see text, web for more details on these)
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