When the classical parametric active contour model(Snake) is applied to segment the image, an initial contour must be set near the boundary of ROI and the model cannot segment deeply concave regions accurately.

• 传统的参数活动轮廓模型分割图像时，要求初始轮廓线设置在感兴趣区域的边界附近，曲线在变形过程中难以分割深度凹陷区域。