The approach is to scan the entire area using some pattern like interlaced scanning.
Once we come across 3 closely located points in x direction there is a chance for that point to be a circle hence we just triangulate 3 closest point from there we are calculating the approimate centre and the radius for the circle.
Is the pattern we are searching for is a line then it can located by finding 2 closer y values.
From there can calculate slope betweeb the two points and then try to locate the rest of the points