unsharpMask:MultipassFilter< { amount:{ default:1; description:"How strongly the detail is boosted; 0 changes nothing."; label:"Amount"; max:5; min:0; step:0.01; type:"float"; }; sigma:{ default:2; description:"Size of the blur that is subtracted, in pixels. Small boosts fine texture, large boosts broader contrast."; label:"Radius σ (px)"; max:50; min:0.3; step:0.1; type:"float"; unit:"px"; }; }, > = ...
Unsharp mask: c' = c + amount · (c − gaussian(c, σ)) on colour; alpha kept, colour floored at 0.
No threshold yet: a hard threshold makes GPU/CPU parity unstable at the boundary.
Unsharp mask: c' = c + amount · (c − gaussian(c, σ)) on colour; alpha kept, colour floored at 0. No threshold yet: a hard threshold makes GPU/CPU parity unstable at the boundary.