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threshhold adjustment issue

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the threshhold adjustment with Threshhold set to 0 should normally deliver a pure white image, independent from the RGB values of the pixels below.

Interestingly, whend used after a highpass filter it occasionally leaves many black spots - even when rasterized or exported as TIF.

I assume a rounding issue.

i If you decrese the value input variable "a" in the PT filter by 1, you get an all-white result (as expected without this round-up).





- the rounding issue is consinstent in all 16-bit color formats with 1/2^16 (testet RGB/GRAY/LAB), and 1/2^8 in all 8-bit color formats (tested RGB/8).


Mac mini M1 A2348

LG34WK950U-W, calibrated to DCI-P3 with LG Calibration Studio / Spider 5

iPad Air Gen 5 (2022) A2589

Special interest into procedural texture filter, edit alpha channel, RGB/16 and RGB/32 color formats, stacking, finding root causes for misbehaving files, finding creative solutions for unsolvable tasks, finding bugs in Apps.


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