Bug 508414

Summary: KolourPaint image preview is pixelated with display scaling >100%
Product: [Applications] kolourpaint Reporter: Carlos Suele <szkaroly93+kde>
Component: generalAssignee: kolourpaint-support
Status: RESOLVED DUPLICATE    
Severity: normal CC: bugseforuns
Priority: NOR    
Version First Reported In: 25.04.0   
Target Milestone: ---   
Platform: Debian stable   
OS: Linux   
Latest Commit: Version Fixed In:
Sentry Crash Report:
Attachments: App window

Description Carlos Suele 2025-08-18 09:20:09 UTC
Created attachment 184201 [details]
App window

SUMMARY
KolourPaint image preview is pixelated when display scaling is set above 100%

STEPS TO REPRODUCE

Set display scaling to more than 100% (e.g. 125% or 150%).

Open an image in KolourPaint.

Look at the internal image preview.

OBSERVED RESULT
The image preview looks very pixelated and low-quality.

EXPECTED RESULT
The image preview should scale smoothly without pixelation.

SOFTWARE/OS VERSIONS
Linux/KDE Plasma: Debian GNU/Linux 13
KDE Plasma Version: 6.3.6
KDE Frameworks Version: 6.13.0
Qt Version: 6.8.2
Kernel Version: 6.15.8-061508-generic (64-bit)
Graphics Platform: X11
Processors: 12 × Intel® Core™ i5-10400F CPU @ 2.90GHz
Memory: 16 GiB of RAM (15.5 GiB usable)
Graphics Processor: AMD Radeon RX 580 Series
Manufacturer: ASUS

ADDITIONAL INFORMATION
See attached screenshot: the image preview in KolourPaint looks very pixelated when display scaling is above 100%.
Comment 1 Patrick Silva 2025-08-18 12:56:09 UTC

*** This bug has been marked as a duplicate of bug 436615 ***