Robust multi-focus image fusion using focus property detection and deep image matting

Multi-focus image fusion techniques are designed to integrate the focused regions of multiple source images to produce an all-in-focus image. Unfortunately, the fusion results generated by existing methods are prone to suffer from chromatic aberrations and blurred boundary regions. In this paper, a multi-focus image fusion framework combining focus property detection and deep image matting is proposed to achieve high-quality fusion results. Specifically, we introduce spatial frequency detection blocks, which integrate the spatial frequency information of source images at different levels to achieve effective focus property detection for the initial decision. Then, the trimap acquired from the initial decision is optimized using a deep matting model so as to further detect the focused/defocused boundaries and obtain a more precise decision map. Meanwhile, a new hybrid loss function is introduced, and a large-scale dataset is created to improve the performance of the fusion framework. Finally, the fusion result is obtained by integrating the focused regions via the decision map. Compared to 18 other advanced fusion methods, the proposed method outperforms all of them in terms of the seven objective metrics evaluated on two publicly available datasets. These experimental results provide strong evidence that the proposed fusion framework excels not only in subjective vision but also in quantitative analysis. The code of the proposed method will be available at https://github.com/govenda/DIMF.