Revision history [back]

I was wondering what sort of sensor gives you this output and what you are looking for (if it's not a secret). As mentioned in comment by @Guanta, the standard way to search for circles is to use Hough transform houghCircles. But in your case the noise is probably too high.

If you have access to gray-scale pixel values you may thing about some image filtering and apply Hough transform on the filtered image.