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izoom - magnify or shrink an image
/usr/sbin/izoom inimage outimage
xscale yscale [-i -b -t -q -m or -g] [-w blurfactor]
izoom magnifies
or shrinks an image with or without filtering. xscale and yscale are floating
point scale factors. The filtering method is one pass, uses 2-d convolution,
and is optimized by integer arithmetic and precomputation of filter coefficients.
Normally izoom uses a triangle filter kernel in both x and y directions.
The -i (impulse) option causes izoom to do no filtering as the image is
resized. The -b (box) option causes izoom to use a box as the filter kernel.
The -t (triangle) option is the default. The -q (quadratic) option indicates
that a quadratic function should be used as the filter kernel. The -m option
uses a Mitchell kernel and the -g option uses a Gaussian kernel. The -w blurfactor
option specifies the width of the reconstruction filter. This will effect
how blurry the resulting image is. If you want more blur use a larger number.
The default value is 1.0. NOTE: izoom does not work on dithered images which
are nothing more than color look-up table indices. To perform any such image
processing one must first use something like fromdi (in the moregltools
subsystem, and also can be found in /usr/people/4Dgifts/iristools/imgtools/fromdi.c),
which converts the dithered image into an RGB image.
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