[GEM-dev] [ pd-gem-Bugs-2835102 ] pix_add yields incorrect results

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Bugs item #2835102, was opened at 2009-08-10 21:22
Message generated for change (Tracker Item Submitted) made by zmoelnig
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Category: None
Group: None
Status: Open
Resolution: None
Priority: 5
Private: No
Submitted By: IOhannes m zmlnig (zmoelnig)
Assigned to: Nobody/Anonymous (nobody)
Summary: pix_add yields incorrect results

Initial Comment:
i noticed that a patch  which adds to pixes (for a feedback) behaves differently on RGBA and YUV: running on YUV will create some saturated effects, while on RGBA it looks ok.
a closer inspection of my patch showed, that i am pre-multiplying the two images one with 1.001 the other with 0.001;
i guess i did this, because on RGBA (which is my default colourspace) the image started to fade-out if the 2 values sum-up to 1.
so the problem seems to be in RGBA rather than YUV...

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You can respond by visiting: 
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