The luminance components of the input color images are processed with nonsubsampled Contourlet transform (NSCT). The decision map is attained by fusing the high frequency coefficients through the scheme of Synthesis Image Coefficient Value Select Maximum (SI-CVSM). Then the decision map is verified by consistency verification and is used to select the RG,B components simultaneously. Experiment results show that the proposed algorithm avoids color distortion caused by fusion algorithms in RGB space model. At the same time this method is only the luminance component integration, thereby reducing the computational complexity. The fused image, which not only retains the important information existing in the input color images, but also improves the detail expression, is more adaptive to the vision of human beings. The integration method is also applied to gray-scale multi-focus image integration in this paper, and the practice shows it is pretty effective.