MULTIRESOLUTION REGISTRATION OF COROLLARY ARTERY IMAGE SEQUENCES

Registration of coronary arterial images taken at different times is v ery important for obtaining better visibility of differences between s equential images. A typical image registration algorithm often employs a similarity measure to detect the differences generated from the rel ative motion or gray level changes between these images. Although a nu mber of image registration approaches have been proposed to resolve th e registration problem of digital angiography, they are either computa tionally expensive or not very robust in the application to practical images. This paper presents a feature-based sum of absolute values of difference (SAVD) using a coarse-to-fine strategy. The proposed algori thm was demonstrated to be capable of automatically registering the ar terial structures in the areas of interest selected from a pair of seq uential images as well as providing fractional pixel precision in regi stration. Compared to other existing methods, the algorithm improves t he speed and the reliability of registration when a pair of coronary a rterial images are acquired at the same or almost the same phase of ca rdiac motion. (C) 1996 Elsevier Science Ireland Ltd.