Guided filter-based multi-focus image fusion through focus region detection

Being an efficient method of information fusion, multi-focus image fusion has attracted increasing interests in image processing and computer vision. This paper proposes a multi-focus image fusion method based on focus region detection using mean filter and guided filter. Firstly, a novel focus region detection method is presented, which uses guided filter to refine the rough focus maps obtained by mean filter and difference operator. Then, An initial decision map is got via the pixel-wise maximum rule, and optimized to generate final decision map by using guided filter again. Finally, the fused image is obtained by the pixel-wise weighted-averaging rule with the final decision map. Experimental results demonstrate that the novel focus region detection method has stronger robustness to different noises, and higher computational efficiency than other focus measures. Furthermore, the proposed fusion method implements efficiently and outperforms some state-of-the-art approaches both in visual effect and objective evaluation.