Anti-aliasing

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mad_b
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Joined: 2014-04-07T05:33:08-07:00
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Anti-aliasing

Post by mad_b »

Would it be feasible/easy to allow me to choose when NOT to use anti-aliasing?
Particularly, I would like to make a SHEAR operation on an image, *without* anti-aliasing. It seems the source code that says to be based on a paper, did not follow the paper that had an if test allowing the user to choose whether not to use anti-aliasing.
I am trying to work with B&W images that get terribly damaged when sheared with anti-aliasing (the default mode of IM).
I need to shear the image that will be "de-sheared" by another processing step, but the current IM shear process add lots of middle tones in the processing step, that ruin the next processing step in my use case.

Thanks
Lissandro
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fmw42
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Joined: 2007-07-02T17:14:51-07:00
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Location: Sunnyvale, California, USA

Re: Anti-aliasing

Post by fmw42 »

What version of IM and what platform? What was your exact command?

try

Code: Select all

convert image -filter point -shear ... result
or

Code: Select all

convert image -interpolate nearestneighbor -shear ... result
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