Otsu’s method is a frequently used thresholding segmentation method.In this paper

in order to utilize the information of edge region

we present a curve thresholding segmentation method based on two-dimensional Otsu’s method.The traditional two-dimensional Otsu’s method can be regarded as a special case of it.Experimental results show that for images with noise the proposed method can obtain better segmentation effect than the traditional two-dimensional Otsu’s method.In order to decrease the amount of computation and promote the speed of segmentation

a recursive algorithm and a wavelet transfer combining with the recursive algorithm are shown.The recursive algorithm only need search the main-diagonal and one sub-diagonal of the two dimensional histogram.Compared with the recursive algorithm of traditional two-dimensional Otsu’s method

the searchin

g space is obviously decreased from searching

L×L

points to 2

L

-1 points.