ImageSubtract

ImageSubtract[image,x] subtracts a constant amount x from each channel value in image.

ImageSubtract[image1,image2] gives an image in which each pixel is obtained by subtracting the values of the corresponding pixels in image1 and image2.

ImageSubtract[image,expr1,expr2,…] subtracts all expri from image, where each expri can be either an image, a number, or a color value.

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