A New Multiresolution Medical Image Registration Algorithm Based on Intensity and Edge Information

To improve the medical image registration accuracy and efficiency, a new approach of image registration based on circular symmetric multiresolution decomposition and edge information is proposed. The translation- and rotation- invariance of the multi-resolution analysis improves the registration accuracy and avoids trapping in local extrema which frequently leads to misregistration. Firstly low pass subbands in the multiresolution decomposition preserve the global image information, and are utilized to perform image registration based on mutual information. Then the cross-weighted moments are calculated in the first level of band pass subband which includes sufficient spatial information. It provides the initial transformation parameters to the hierarchical registration. So the transformation displacements will be calculated rapidly and accurately in the optimization algorithm. Experiments demonstrate that the intensity and edge information combined method based on circular symmetric pyramid improves the registration accuracy and robustness. It also reduces the iterations of optimization and has low computation complexity.