Abstract: Multimodality medical image fusion is significant in practical clinic application and therapy. According to characteristics of the regional relativity in the low-frequency sub-band and high frequency sub-band, CT and MRI images were decomposed by lifting wavelet transform. Region variance was adopted as fusion rules in the low frequency sulrband, and fusion rules based on region spatial frequency was adopted in the high frequency sub-band. Finally the fusion image was obtained by taking inverse lifting wavelet transform. Compared with the traditional methods,the results of experiment show that the algorithm enhances the fusion medical image information, effectively retains the source image edges and detail information, and the effect of fusion and quantifying indicators are fairly good.

Key words: Medical image fusion, Lifting wavelet transform, Region variance, Region spatial frectuency