A Gray-Level Image Registration Algorithm for DSA Image Based on Subtraction Histogram and Gray Value Shift Mesh
Ying Chu · Dianzi xuebao · 2006
A new gray-level registration algorithm for digital subtraction angiography (DSA) image based on subtraction histogram (the histogram of subtraction image) and gray value shift mesh is firstly proposed in this paper.Differences of gray values generated by gray-level distortions between mask and live images can be effectively eliminated by the presented algorithm.Therefore,the lost details in subtraction image could be restored.The gray value shift (GVS) of each pixel is calculated from the information contained in the subtraction histogram.In order to reduce the computation time,gray value shift mesh is proposed to achieve the tradeoff between registration effect and computation speed.Various experiment results have shown that this algorithm can effectively reduce artifacts and the visual quality of vessels in subtraction image is significantly improved.