Appearance flow based structure prior guided image inpainting

Image inpainting techniques based on deep learning have shown significant improvements by introducing structure priors, but still generate structure distortion or textures fuzzy for large missing areas. This is mainly because series networks have inherent disadvantages: employing unreasonable structural priors will inevitably lead to severe mistakes in the second stage of cascade inpainting framework. To address this issue, an appearance flow-based structure prior (AFSP) guided image inpainting is proposed. In the first stage, a structure generator regards edge-preserved smooth images as global structures of images and then appearance flow warps small-scale features in input and flows to corrupted regions. In the second stage, a texture generator using contextual attention is designed to yield image high-frequency details after obtaining reasonable structure priors. Compared with state-of-the-art approaches, the proposed AFSP achieved visually more realistic results. Compared on the Places2 dataset, the most challenging with 1.8 million high-resolution images of 365 complex scenes, shows that AFSP was 1.1731 dB higher than the average peak signal-to-noise ratio for EdgeConnect.