Color
/ Grey Scale
It may happen that we need to drop color information from the image. For example, we want to use a mathematical operation that can only be applied to a grayscale image.
We can do the transformation to grayscale in several ways. The resulting value will always depend on all three color components (red, blue, green). We only need to choose the transformation ratio:

Preview
Example
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Original image After conversion - standard (Rec.709)
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After conversion -
nonlinear luma After conversion
- average
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