According to the defect that it is easy to produce the edge distortion s and lose clear regional contrast in the fusing process for multi-focus images ,thi s paper proposes a novel multi-focus image fusion algorithm.Firstly,this algori thm gets the decomposed high-frequency and low-frequency sub-band coefficients by the discrete Ripplet transform (type-I).For the low-frequency sub-band coefficients,it adopts the 3-layer non-subsampl ed contourlet transform (NSCT) to conduct coefficients fusion.For the high-freq uency sub-band coefficients,the orthogo nal matching pursuit (OMP) algorithm is used to seek the over-complete dictionary sparse representation coefficients.Then the coeff icient vector activity rules are used to perform the efficient fusion and construct the corresponding coefficients matrix.Finally,t he inverse Ripplet transform is used to get the final fused images.The experiment results show that this algorithm could bette r keep the multi-focus images edge contour and improve the contrast of the clear part,and in the objective evaluation,the algorithm of this paper has a certain advantage on mutual information and the degree of edge keeping.