Box filter Resize Bug

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anthony
Posts: 8883
Joined: 2004-05-31T19:27:03-07:00
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Box filter Resize Bug

Post by anthony »

Box resize changed..


I have no idea why but the Box filter is now producing a non-symetric result!

test image

Code: Select all

convert -size 10x10 pattern:gray50  checks_10.gif
Image
Box filter resize 2 pixels smaller.

Code: Select all

convert checks_10.gif -filter box -resize 8x8 -sample 80x80 checks_box-2.gif
Image
previously it generated the symetric image
Image

This was BEFORE I updated IM to the one with the new resize patches.

Looks to be something bery basic changed as it is after all, just trhe box filter
The exact same test using a triangle filter does NOT show this problem, so it may be a boundary problem only visible with box as it has a sharp window boundary.
Anthony Thyssen -- Webmaster for ImageMagick Example Pages
https://imagemagick.org/Usage/
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magick
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Joined: 2003-05-31T11:32:55-07:00

Re: Box filter Resize Bug

Post by magick »

It was a boundary condition. Fixed. Thanks.
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