The images to be processed is obtained in condition of nonuniform illumination . a threshold surface by interpolating zero - crossing points is used to segment image to avoid influence of nonuniform illumination . then the destination region can be detected using the method of pattern recognition and the method advoid the influence of nonuniform illumination effectively . the contour description is obtained by fitting at least squares principle 论文在分析当前图象分割的现状和趋势的基础上，采用基于log算子的动态阈值选取对图象进行分割，以克服非均匀光场给图象分割带来的影响，然后通过对区域特征的提取和分类准则的确定，准确识别出目标区域。
