结合分水岭算法的水平集医学图像分割方法

Level Set Medical Image Segmentation Method Combining Watershed Algorithm

由于医学图像中的复杂目标通常难以被完全分割,提出标记分水岭与改进型Li模型的组合图像分割算法。改进型Li模型构造了符号压力函数来取代传统的停止函数,解决了曲线单向演化的问题。标记分水岭具有较强的抑制噪声的能力,对医学图像的弱边缘具有较强的捕获能力。所以首先运用标记分水岭算法对图像进行预分割,快速准确定位目标区域边缘信息。再引入改进型Li模型算法,通过符号压力函数来指引曲线演化方向,控制演化速度大小,实现对复杂目标的完全分割。实验结果表明:全局信息和边缘信息都能被获得,该组合算法对医学图像中的复杂目标的分割效果较满意。

Complex targets of medical image are usually difficult to be completely segmented,so an image segmentation algorithm of modified Li model combining mark watershed algorithm was proposed.A symbol pressure function replaces the traditional stop function in Modified Li model,and the problem of unidirectional curve evolution is solved.Mark watershed has both stronger ability to suppress noise and stronger ability to capture weak edge of medical image.Firstly,mark watershed algorithm is used for image segmentation pretreatment,positioning information of target edge fast and accurately.Then,the modified Li model algorithm is introduced,and the symbol pressure function is used to guide curve evolution direction and control the size of the evolution speed,realizing full segmentation of complex object.The experimental results show that global information and edge information can be gooten,and the combination algorithm of complex targets can get satisfactory effect in the medical image segmentation.