Calculates an Image Derivatives Using a Scharr Operator

sobel calculates the derivatives of an image using a Scharr operator.

scharr(image, dx = 1, dy = 1, scale = 1)

Arguments

image	An `Image` object.
dx	Order of the x derivative (default: 1).
dy	Order of the y derivative (default: 1),
scale	The scale factor for the computed derivative values (default: 1).

image An Image object.

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