Medical Image Registration Based on Wavelet Transformation and Mutual Information
基于小波变换和互信息的医学图像配准

To improve the performance of medical image registration technology,a new method based on wavelet transformation and mutual information is proposed in this paper.Decomposed wavelet sub-bands of the original images are obtained using the wavelet transform.Coarse-to-fine multi-resolution search approaches have been performed.Registration at higher levels can be performed with the result at the pervious level serving as the initial condition.Down simplex method with limited boundary is used as optimization strategy.Besides,different methods are used at different levels.Regional mutual information(RMI) which takes geometry into account is used as similarity measure at low levels and PV interpolation is applied at high level in order to prevent the optimizing process from being tapped into local maximums.The algorithm has been applied on noisy MR mono-modality,PET mono-modality and MR-PET multimodality medical image registration.The results show that the algorithm performs fairly well.Compared with the traditional algorithms,the algorithm has some advantages such as higher precision and better anti-noisy performance as well as higher computation efficiency.