Yes. viscircles() does not find circles though - perhaps you meant imfindcircles().
I don't have your code so I can't extend it so I'll just give you the steps.
- Use strel() to construct a disc structuring element
- Use imdilate() to dilate your binary image (circles mask) to enlarge the circles
- Use ringMask = xor(mask, dilatedMask) to get the annular mask.
- Use the annular mask to set the gray scale image to 0 there: grayImage(ringMask) = 0;
Attach your image and code to produce the circles if you can't do it.
