Abstract
This paper proposes an improved method to detect a crack of drain. The conventional method tends to fail to detect a crack where its direction is changed. The proposed method solves this problem by smoothing structures of crack. A crack has a global direction in large scaled background structures. Therefore the smoothing process to the direction of a crack is supposed to be useful for reducing noise structures without the influence to crack structures. It makes the continuity of cracks improved, and helps the crack detection method to obtain superior results. The two processes are repeated in the proposed method: one is the crack detection process and the other is the noise-reducing process. The experimental results show that the proposed method is useful for improving the detection rate of the crack pixels in comparison with the conventional method.
