摘要： 多相图像分割通常利用多个水平集函数分别定义不同区域的特征函数，其极值求解问题需要对多个函数分别求极值，计算效率较低。针对三维多相图像，提出一种改进的变分水平集模型，采用一个多层水平集函数的n层水平集隐式曲面，将图像划分为n个区域，通过对一个水平集函数求极值，实现三维多相分段常值图像的快速分割与重建。将能量泛函表达为数据项和规则项，借助规则化Heaviside函数设计区域划分的通用特征函数，采用Split-Bregman投影方法进行能量最小化求解。实验结果表明，该模型可以有效地实现三维多相图像分割，与Chan-Vese模型相比，其迭代步数较少，分割速度较快。

关键词: 三维图像分割, 多相图像分割, 变分水平集方法, 多层水平集函数, Split-Bregman方法

Abstract: Multiphase image segmentation is usually realized by using multiple level set functions to respectively define the characteristic functions in different regions.However,the solution to the extremum of multiphase image segmentation relies on the solution to the extrema of multiple functions,leading to low computational efficiency.Aiming at the 3D multiphase images,this paper proposes an improved variational level set model.In this model,the implicit surface evolution of an n-layer level set in a multilayer level set function is used to divide the image into n regions.Then,according to the solution to the extremum of a level set function,the 3D multiphase segmented constant valued image is rapidly segmented and reconstructed.This model also expresses the energy functional as data item and regulation item,and designs the general characteristic function of domain partition by using regularized Heaviside function.Finally,the Split-Bregman projection method is used to conduct the energy minimization solution.Experimental results show that the proposed model can effectively realize 3D multiphase image segmentation.Compared with the Chan-Vese model,this model needs less iteration steps and has faster segmentation speed.

Key words: 3D image segmentation, multiphase image segmentation, variational level set method, multilayer level set function, Split-Bregman method

中图分类号: 

• TP391