cv2.findCirclesGrid fails on simple image

Hey!

I have some trouble with finding asymetric circle patterns e.g. in this very simple case where I even did some preprocessing: [URL=http://www.directupload.net/file/d/3826/76en8sgf_png.htm][IMG]http://fs1.directupload.net/images/141204/temp/76en8sgf.png[/IMG][/URL]

findCirclesGrid fails to find the grid (I check for (11,3) and (3,11) grids as I'm not really sure how OpenCv counts)

Has anyone an idea?

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