基于方向场分布率的静脉图像分割方法

提出了一种新的静脉图像分割方法, 该方法以方向场分布率(Distribution ratio of directional fields, DRDF)作为区分静脉纹路和背景的分割准则. 首先利用邻域信息和邻域分块模板计算图像中每个像素点的方向场以生成方向场图像, 然后根据方向场图像中像素点互补半圆区域内的方向场分布率和分布判定函数计算出8灰度级图像, 最后确定二值化参数将8灰度级图像二值化得到最终图像分割结果. 该方法结合静脉图像特征, 充分利用方向场图像的空间属性,克服了照度不均、粗细不均以及边界模糊等因素对分割造成的影响. 实验结果表明该方法对于静脉图像具有很好的分割效果.

Vein Image Segmentation Based on Distribution Ratio of Directional Fields

In this paper, a novel segmentation algorithm is presented to improve segmentation performance for vein images. The proposed algorithm uses the distribution ratio of directional fields (DRDF) as the segmentation principle to distinguish vein lines from background. First, the neighbor information and template of neighbor segmentation are used to obtain directional fields for every pixel in the original image. Then in image of directional fields, DRDF of complementary semi-circle regions and distribution discrimination function are used to calculate the 8-grayscale image. Finally, a threshold is set to binarize the 8-grayscale image to obtain segmentation results. The algorithm combines the feature of vein image and spatial properties of directional fields image. Experiment results show that it is very effective for vein image with non-uniform illumination, inhomogeneous thickness, and blurry boundary.