[magick-users] RE: on destriping again.. low & high pass filter.. how to do pixel algebra in IM

[Anthony Thyssen]

Fred Weinhaus on  wrote...
| Use -fx, but it is slow or if you have just add, subtract and 
| multiply (no division or other more complex factors) you can use 
| -compose [plus, minus, multiply] -composite
| 
| 
| See
| 
| http://www.imagemagick.org/script/fx.php
| http://www.imagemagick.org/Usage/transform/#fx
| http://www.imagemagick.org/Usage/compose/
| 
| 
If you are adding subtracting or multiplying by a constant
you can use the faster  -evaluate   operator.

http://imagemagick.org/Usage/transform/#evaluate

  Anthony Thyssen ( System Programmer )    <A.Thyssen at griffith.edu.au>
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  As flat as an open can of coke, left on a programmer's desk over the weekend.
                                          --- Rick Cook, "Wizardry Consulted"
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     Anthony's Home is his Castle     http://www.cit.gu.edu.au/~anthony/