Introduction - If you have any usage issues, please Google them yourself
This function calculates the radial derivative of an input image.
Input parameters:
inputImage - the image to calculate the derivative from
radialFilterLength - the length of the filter to use, total length
will be 2*radialFilterLength+1
centerX and centerY - the point that is considered the center of the
image, for the calculation
minRadius and maxRadius - the minimum and maximum radius to calculate
the angular derivative for.
radialApproach - set to 1 to use a radius and angle search method, or 0
for a per-pixel approach