Discrete wavelet transform (DWT) has become an attractive tool of image registration,however,it is shift-sensitive.Some modified schemes of DWT,such as DTCWT (dual-tree complex wavelet transform),always lead to high computational complexity in registration process because of redundancy.In this paper,it showed that the shift-sensitivity was caused by the downsampling operation in the analysis process,which could be expressed by the aliasing terms in the frequency-domain.A new scheme for the design of wavelets was proposed to approximately eliminate the effect of downsampling while remains the wavelet representation nonredundancy.The design example illustrated the shift sensitivity of wavelet representations was reduced efficiently without any redundancy.The registration results of two medical images further proved the validity of design scheme and effectiveness of the proposed wavelet.
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