This is an edge detector with SUSAN algorithm.
effect without non maximum suppression:
effect with non maximum suppression:
effect without non maximum suppression:
effect with non maximum suppression:
1.1 opencv library
The following summary is copied from here, you can also see more details about this algorithom from it.
2.1 Place a circular mask around the pixel in question (the nucleus).
2.2 Calculate the number of pixels within the circular mask which have similar brightness to the nucleus. (These pixels define the USAN.)
2.3 Subtract the USAN size from the geometric threshold to produce an edge strength image.
2.4 Use moment calculations applied to the USAN to find the edge direction.
2.5 Apply non-maximum suppression, thinning and sub-pixel estimation, if required.
The effect seems not to be the best. I will updata the effect image after the code being improved.