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How to remove overlapping red and green color regions, leaving only red ones?

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ImageApply might be useful – ssch Oct 20 '13 at 21:52
up vote 5 down vote accepted

This removes the "overlapping" areas, assuming the green area doesn't have holes exactly where the red is, leaving the red areas only outside the green area:

img = Import[""]
{r, g, b, alpha} = ColorSeparate[img];
n = Image[0*ImageData[r]];
rnew = ImageMultiply[ColorNegate@Closing[Binarize[g], 4], r]
ColorCombine[{rnew, n, n}]

Mathematica graphics

This code simply removes the green:

rnew2 = ImageMultiply[ColorNegate@Binarize[g], r]
ColorCombine[{rnew2, n, n}]

Mathematica graphics

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