Bug 301637

Summary: Image upsampling is not gamma-correct
Product: WebKit Reporter: Nico Weber <thakis>
Component: ImagesAssignee: Nobody <webkit-unassigned>
Status: NEW    
Severity: Normal CC: heycam, sabouhallawa, simon.fraser, webkit-bug-importer
Priority: P2 Keywords: InRadar
Version: Safari 18   
Hardware: Mac (Apple Silicon)   
OS: macOS 15   

Nico Weber
Reported 2025-10-29 10:07:32 PDT
Steps to reproduce: Looked at an image while using a retina screen Actual results: Safari upsampled the image 2x (good), but didn't do take gamma into account. Expected results: Safari should use a gamma-correct image resampling algorithm. I made a demo / repro here: https://nico.github.io/hack/web/gamma-upsample.html Here's a detailed explanation: http://www.ericbrasseur.org/gamma.html Browsers fixed their downsampling in response to that page long ago, but not their upsampling.
Attachments
Radar WebKit Bug Importer
Comment 1 2025-10-29 11:04:37 PDT
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