How do I get this object in the image

In the follow image there are 9 'round objects' in the round object there are black and white defects, how am i suppose to obtain them. I was asked to extract and find the area of the black and white defects from the 'round shaped objects '

[Chok Chuan]

Here

[rizwan]

Hi CHok,

Your problem is to extract features or descriptors from an Image, common feature extraction techniques are Histogram of Oriented Gradients (HOG), Speeded Up Robust Features (SURF), Local Binary Patterns (LBP), Haar wavelets, and color histograms.

Thanks