Bug 473157 - Improvement of unsharp mask
Summary: Improvement of unsharp mask
Status: RESOLVED FIXED
Alias: None
Product: digikam
Classification: Applications
Component: Plugin-Editor-Sharpen (show other bugs)
Version: 8.0.0
Platform: Ubuntu Linux
: NOR wishlist
Target Milestone: ---
Assignee: Digikam Developers
URL:
Keywords:
Depends on:
Blocks:
 
Reported: 2023-08-08 14:28 UTC by foto19@ernst-buerjes.de
Modified: 2024-05-21 07:58 UTC (History)
1 user (show)

See Also:
Latest Commit:
Version Fixed In: 8.4.0
Sentry Crash Report:


Attachments
enlargement about 300 % (2.15 MB, image/png)
2023-08-08 14:28 UTC, foto19@ernst-buerjes.de
Details
Screenshot_20230808_192751.png (16.05 KB, image/png)
2023-08-08 17:29 UTC, foto19@ernst-buerjes.de
Details
Screenshot_20230808_192751.png (16.05 KB, image/png)
2023-08-10 10:29 UTC, foto19@ernst-buerjes.de
Details

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Description foto19@ernst-buerjes.de 2023-08-08 14:28:57 UTC
Created attachment 160836 [details]
enlargement about 300 %

I wanted to sharpen a picture and I decided to take the tool "unsharp mask".
Instead of sharpend borders I got the same borders as before but white and black spots on over- and underexposed places.
Comment 1 caulier.gilles 2023-08-08 14:35:50 UTC
This kind of side effect is normal with unsharp-mask mechanism. Try the refocus tool, or better the GMicQt plugin available in AppImage bundle.

Gilles Caulier
Comment 2 foto19@ernst-buerjes.de 2023-08-08 17:29:54 UTC
Created attachment 160840 [details]
Screenshot_20230808_192751.png

Hi Gilles,

Thank you for the very quick response.

I tried the refocus tool, but I did not find any adjustment which made 
the picture better.

Then I downloaded DigiKam.appimage 8.1 and I installed it. Now I am 
looking for the GMicQt plugin and cannot find it.

Another Question: Is there an adjustment to see the pixels in very great enlargements (See my attachment)?  In DigiKam it seems, that the pixels are smoothed.

Thank you for your help
Ernst


Am 08.08.23 um 16:35 schrieb bugzilla_noreply@kde.org:
> https://bugs.kde.org/show_bug.cgi?id=473157
>
> caulier.gilles@gmail.com changed:
>
>             What    |Removed                     |Added
> ----------------------------------------------------------------------------
>             Severity|major                       |normal
>
> --- Comment #1 from caulier.gilles@gmail.com ---
> This kind of side effect is normal with unsharp-mask mechanism. Try the refocus
> tool, or better the GMicQt plugin available in AppImage bundle.
>
> Gilles Caulier
>
Comment 3 caulier.gilles 2023-08-08 22:44:48 UTC
GMicQt is in Image Editor only:

https://docs.digikam.org/en/image_editor/enhancement_tools.html#g-mic-qt-tool

Gilles Caulier
Comment 4 foto19@ernst-buerjes.de 2023-08-10 10:29:48 UTC
Created attachment 160886 [details]
Screenshot_20230808_192751.png

Hi Gilles,

thank you for the hint to the DigiKam-Manual. Now I found, that I have 
already been working with the GMicQt plugin. The difficulty for me was, 
that the warning on over- and under-exposure ist switched on by default. 
I found it out by accident, I pressed F10 and F11 and everything was good.

But it would help a lot working with sharpening-tools, no matter which, 
when one could switch the pixels "on" as to see in my attachment. With 
the visible pixels you can see exactly when the sharpness is good and 
when you sharpen too much. Where did the developers of DigiKam hide this 
switch? It should be in the Image Editor somewhere in the "view"-Menü.

Best regards
Ernst
Comment 5 caulier.gilles 2024-05-21 07:58:46 UTC
The Unsharped Mask filter from the new GmicQt 3.3.7 integrated in next digiKam 8.4.0 generate excellent results.

https://i.imgur.com/syULTxi.png

Gilles Caulier