Texture-Enhanced Framework by Differential Filter-Based Re-parameterization for Super-Resolution on PC/Mobile

In this paper, we aim to improve the imaging quality of super-resolution (SR) without increasing the inference time to address the difficulty of trading off between quality and inference time in many existing methods and design a deployment-friendly, lightweight model for mobile devices. Specifically, we propose a general RepDFSR framework to enhance the textures of SR images while avoiding additional inference time overhead, which can be applied to existing SR networks. It incorporates innovative convolutional block design, loss function design, and the re-parameterizable technique. In RepDFSR, we propose a re-parameterizable texture-enhanced convolution based on differential filters. It extracts texture information more advantageous and efficient in training than regular convolution. Secondly, we propose a DF loss function to compel the model to super-resolve the gradient mappings with high variance, thus reconstructing images with sharper textures. Moreover, we propose a TELNet network for mobile devices based on the RepDFSR framework to validate the effectiveness of RepDFSR and our thoughts on practical applications of SR on mobile devices. The experimental results demonstrate the successful integration of the RepDFSR framework with the existing SR methods. Additionally, the TELNet meets the requirements of mobile devices for hardware and quantization limitations, showcasing superior SR performance compared to classic and state-of-the-art methods.