Fig. 3
From: An unsupervised image segmentation algorithm for coronary angiography
The edges of the blood vessels were usually uneven and jagged when the images underwent binarization. (a) the example blood vessel clearly extends vertically in the coronary angiograph, (b) only the shortest cover from the edge of each pixel was considered. The cover direction was complex thus affecting the accuracy with which the vessel diameter changes were traced, (c) presents the application results of the cover selection conditions. The middle section appears black since it was covered by a continuous, dense horizontal cover