1.7.1 - effects - Equalize, Posterize - few issues

Reported bugs that have been closed and/or resolved

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user0
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1.7.1 - effects - Equalize, Posterize - few issues

Post by user0 »

XnViewMP 1.7.1 64bit
Windows11 (23H2), display resolution 3840x2160, win scaling 150%


Viewer > Image > Adjust
  • Posterize...
    - issue at 37 value
    - looks like no effect in 150-256 range
  • Equalize
    - issue with 32bit png w alpha channel
    test_img_32bit_transparency.zip
    (160.97 KiB) Downloaded 51 times
    equalize_result.png
    equalize_result.png (30.1 KiB) Viewed 1877 times

    I doubt that this is desired result, eg in adobe:
    The Equalize filter redistributes the brightness values of the pixels in an image so that they more evenly represent the entire range of brightness levels. When you apply this command, Photoshop Elements finds the brightest and darkest values in the composite image. It then remaps them so that the brightest value represents white and the darkest value represents black. Photoshop Elements then equalizes the brightness—that is, distributes the intermediate pixel values—evenly throughout the grayscale.
Last edited by user0 on Tue May 07, 2024 9:12 am, edited 2 times in total.
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Re: 1.7.1 - effects - Equalize, Posterize - few issues

Post by xnview »

user0 wrote: Sun May 05, 2024 3:15 pm Viewer > Image > Adjust
  • Equalize
    - issue with 32bit png w alpha channel
    test_img_32bit_transparency.zip
what's the problem?
Pierre.
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user0
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Re: 1.7.1 - effects - Equalize, Posterize - few issues

Post by user0 »

I've updated OP
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Re: 1.7.1 - effects - Equalize, Posterize - few issues

Post by xnview »

:bugconfirmed: Thanks to your detailed description I can reproduce the problem.
Pierre.
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Re: 1.7.1 - effects - Equalize, Posterize - few issues

Post by xnview »

This problem is supposed to be fixed in XnView MP 1.7.2. Please check and confirm the bug fix here.
Pierre.
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Re: 1.7.1 - effects - Equalize, Posterize - few issues

Post by user0 »

172
issues still remain
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Re: 1.7.1 - effects - Equalize, Posterize - few issues

Post by xnview »

This problem is supposed to be fixed in XnView MP 1.8.0. Please check and confirm the bug fix here.
Pierre.
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Re: 1.7.1 - effects - Equalize, Posterize - few issues

Post by user0 »

fixed in 180
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