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image processing - What is the meaning of ColorSpace -> Automatic?


The colour space of an image can be retrieved using Options[im] or ImageColorSpace[im]. A possible value is Automatic. This is what we get when using ColorCombine[channels] without specifying an explicit colour space.


What is the exact meaning of Automatic?


It seems to display like RGB when there are three channels. But it works with any number of channels. How is the colour of a pixel computed when we have a different number of channels than three?




Example:


im = ExampleData[{"TestImage", "Sailboat"}]

enter image description here


{r, g, b} = ColorSeparate[im];

ColorCombine[{r, r, g, b}]

enter image description here





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