Spatial domain image fusion using adaptive cross filtering

Abstract We present an algorithm for multifocus image fusion in spatial domain using adaptive cross filtering. The basic idea is to extract the edge information from the source images and then segment the source images into blocks using the soft blending technique instead of splitting them in to simple fixed size blocks. The differences between the average edge information from both the source images is computed and the mean of these differences is set as the threshold. Only those blocks for which the difference exceeds the threshold are chosen and incorporated into the final fused image. A further enhancement is achieved by making this process iterative. In every next iteration, the image is divided adaptively such that each block is subdivided in four parts to the divisions used in the last iteration. Also the number of iterations is varied as per size of image. The performance of this method has been tested on many pairs of multifocus images shows improved results when in comparison with existing methods.