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The CICA Windows Explosion!
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The CICA Windows Explosion! - Disc 2.iso
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demo
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wit472.zip
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DEMO
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COMPLEX.HLP
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COMPLEX.bin
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1994-11-25
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751b
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18 lines
IGRAPH
complexDemo --- perform filtering in frequency domain
DESCRIPTION
The complexDemo igraph shows how an image may be filtered
in the frequency domain using a square cutoff image mask and
complex multiplication operator. The cutoff mask has a centred
square with pixel value one and zeros everywhere else. When this
mask is multiplied with the FFT of the original image, the resulting
complex image is then inverse FFT'ed to produce a smoothed image
with ringing effects. The ringing effects are caused by the square
cutoff mask. The effects can be greatly reduced by approximating the
square with a smoother window. The Welch, Parzen, or Hanning windows
are all possible alternatives and yield much better results.