https://bugs.kde.org/show_bug.cgi?id=524860
Bug ID: 524860
Summary: Saving image to a lossy format significantly worsens
the visual quality
Classification: Applications
Product: Koko
Version First unspecified
Reported In:
Platform: Flatpak
OS: Linux
Status: REPORTED
Severity: normal
Priority: NOR
Component: General
Assignee: [email protected]
Reporter: [email protected]
Target Milestone: ---
Created attachment 195545
--> https://bugs.kde.org/attachment.cgi?id=195545&action=edit
webp image saved from Spectacle at 95% quality (looks good at large size)
STEPS TO REPRODUCE
1. Open a PNG image in Koko
2. Save As > choose webp or jpeg as the format > save
OBSERVED RESULT
The newly-saved file is a ton smaller… and has noticeable visual artifacts
around line-art elements when displayed at large size.
EXPECTED RESULT
One of the following:
- No artifacts (100% quality level used rather than 80%, which is the internal
default in QImageWriter)
- Few artifacts (90-95% quality level)
- A UI slider to choose the quality level that defaults to a value between 90%
and 100%
SOFTWARE/OS VERSIONS
App:
nightly/git master Flatpak build
OS:
Operating System: KDE Linux 2026-08-27
KDE Plasma Version: 6.7.80
KDE Frameworks Version: 6.30.0
Qt Version: 6.11.2
Kernel Version: 7.1.9-arch1-2 (64-bit)
Graphics Platform: Wayland
Processors: 16 × AMD Ryzen 7 7840U w/ Radeon™ 780M Graphics
Memory: 17 GB of RAM (16.0 GB usable)
Graphics Processor: AMD Radeon 780M Graphics
--
You are receiving this mail because:
You are watching all bug changes.