Multi-modal medical image fusion by Laplacian pyramid and adaptive sparse representation.

Multi-modal medical image fusion refers to the fusion of two or more medical images obtained by different imaging methods into one image. Multi-modal medical images contain a lot of useful information that helps doctors to make a diagnosis. In this study, a multi-modal medical image fusion method is proposed based on Laplacian pyramid (LP) decomposition and adaptive sparse representation (ASR). ASR was used to reduce the noise of high-frequency information in the image fusion process and it did not need a high redundancy dictionary as traditional sparse representation (SR) methods. The proposed fusion method first used the LP decomposition to split medical images into four images of different sizes. Then ASR was performed to fuse the decomposed four layers, respectively. Finally, the fused image was obtained by the inverse Laplace pyramid transform. Experimental results showed that the proposed method could effectively fuse the medical images with the detailed information perfectly integrated, and could also reduce the influences of artifacts, noise and block effect. The research results are of great significance in the field of medical image fusion.