Research of multi-focus image fusion based on M-band multi-wavelet transformation

摘要

Image fusion is one of the important embranchments of data fusion. Its purpose is to synthesis multi-image information in one scene to one image which is more suitable to human vision and computer vision or more adapt to further image processing, such as target identification. This paper mainly discusses the image fusion method based on wavelet transformation. Firstly, the article gives the basic concept of multi-focus image fusion. On top of this, the paper gives the theory of wavelet analyses and its fast arithmetic, hereon gives the image fusion method based on singe wavelet. Getting on with the single wavelet, the paper presents some improved wavelet as multi-wavelet, multi-band multi-wavelet, including their theories and their arithmetic of decomposition and reconstruction. At the same time, the article applies the multi-band multi wavelet in the image fusion with the wavelet fusion thought. In the side of selecting fusion arithmetic operators, the paper compares the methods based on pictures, windows and regions, and adopts the fusion norm based on grads and characteristic measurement of regional energy. Besides it compares images which is based on different fusion norms and different wavelets in the aspects of entropy, peak value Signal-to-Noise, square root error and standard error in the experimentation. By using Matlab as experimental platform, we approved the feasibility and validity of the method mentioned in the article through a lot of experiments. The result indicates that multi-band multi-wavelet is very effective in image fusion. Furthermore, the article does some post processing to the fusion image. The method is based on anisotropic diffusion arithmetic based on partial differential equations. The experiments show that the brim diffusion enhanced the PSNR of image with the selective brim diffusion to the fusion image and depressed the image block domino effects caused by wavelet fusion method.