The machine recognition of Chinese ancient copper coin

Chinese ancient copper coins have a square hole inside a circle shape. To recognize Chinese ancient copper coins from a bunch of other stuff, the program needs to recognize the circle shape and the square shape individually. We present a method which can be used to recognize Chinese ancient copper coins efficiently in this article. This method has two steps. Firstly, identify the circle by using the roundness judgment formula. Secondly, identify the square by using the Hough transform. This method is very efficient and can be used in the customs export examination as a common procedure.