There are many ways to convert an image to gray scale. These settings provide functionality to convert images to gray scale where the MedianSmoothing technique gives a perfect result. In more complicated images, less data will be lost by taking the median. MedianSmoothing removes the noise from the image while preserving the image edges.
HLS is also a Color space similar to RGB. But instead of red, green and blue components, HLS contain Hue, Luminance & Saturation components. It’s a color space in which the Hue, saturation and luminance of a color can be separated and modified.
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