A NOVEL SEGMENTATION ALGORITHM OF FINGERPRINT IMAGE

Almost all segmentation algorithms proposed in present papers have a common problem that the threshold value can't be accurately selected. A novel segmentation algorithm for fingerprint images is proposed in this paper, which is combining grey-value method and orientation diagram method with square-error method. When the difference between the grey-value of a ridge and that of a vale is great, foreground blocks of a fingerprint image are decided according to grey-level difference of more appearance frequency of pixels in histogram of the grey-scale. When the difference between the grey-value of a ridge and that of a vale is little, foreground blocks of a fingerprint image are decided according to ridges' orientation, which is that a grey-scale difference is calculated in each direction through 12-orientation template. The proposed method can segment well foreground blocks and background blocks of the fingerprint image. This method can segment foreground blocks and background blocks for the greater difference or less difference between fingerprint image ridge and vale accurately and easily. The boundary of a fingerprint image is obtained easily, while, the original image isn't destroyed. The experimental results show that the segmentation error rate of the proposed method is obviously lower than the square-error method and the improved method based on the square-error method in this paper..