Fix rescaling images with wxIMAGE_QUALITY_BOX_AVERAGE

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Current algorithm used to calculate the bounds of the boxes in the source
image to which the pixels in the target (rescaled) image are mapped to, has
flaws which cause a non-uniform distribution of the boxes in the source
image. And these miscalculations may result in the visible distortions
of the colours in the rescaled image.
New algorithm assures uniform distribution of the boxes in the source image
and thanks to the integer arithmetic is faster than currently used
and not prone to the problems with floating point representation.

Closes #18012.

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This commit is contained in:

Artur Wieczorek

2017-11-30 22:36:51 +01:00

parent 390a3885ba

commit d68bb24333

6 changed files with 33 additions and 27 deletions

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