关键词: 二值化, 图像分割, 空间聚类

Abstract: Image segmentation is an important processing step，but problems always exist such that the result is not satisfied and the computational complexity is too high.A novel method of binarization for gray images is presented.The Ncut（Normalized graph cut） is used as the measure for spectral clustering in the algorithm，and the weight matrixes used in evaluating the graph cuts are based on the gray-scale image，rather than the matrix commonly used based on image pixels.Thus，the proposed algorithm requires much smaller spatial costs and much lower computation complexity.Experiments on text images in natural scene show the superior performance of the proposed method on time and system resources cost compared to the typical threshold algorithms.

Key words: binarization, graph cut, spectral clustering