My link to image is https://drive.google.com/open?id=1Leg6tffN9DJZ-TJJgwoaa-StJktp2x05. My code is ++++++++++++++++++++++++++++++++
I=imread('Pattern4.png'); obj = cv.SimpleBlobDetector('MinThreshold',10,'MaxThreshold',255,'ThresholdStep',10,'FilterByColor',true,'BlobColor',255); keypoints = obj.detect(I2); im_with_keypoints = cv.drawKeypoints(I2, keypoints,'DrawRichKeypoints',true); im_with_keypoints_gray = cv.cvtColor(im_with_keypoints,'RGB2GRAY'); imshow(im_with_keypoints) [ret,corners] = cv.findCirclesGrid(im_with_keypoints,[2,2]);
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Please tell me why i cannot detect the circular grid?