JPEG XL uncommon ICC comparison

icc-uncommon-profile-reftest.html

The Rendered and Expected tabs use the exact assets from the WPT. Diff compares the two live compositor layers with CSS difference blending, preserving differences that canvas readback can hide.

Live with_icc.jxl decoded by this browser.

PNG reference from the WPT.

Live CSS difference blend, brightness amplified 8x. Matching displayed pixels are black.

Canvas readback diagnostic

-canvas-readback pixels

-canvas max delta

-canvas mean delta

Canvas readback can report zero while the live compositor diff remains visible. The two paths do not preserve the same ICC behavior.