Efficient Fine-Tuning Of Neural Networks For Artifact Removal In Deep Learning For Inverse Imaging Problems

While Deep Neural Networks trained for solving inverse imaging problems (such as super-resolution, denoising, or inpainting tasks) regularly achieve new state-of-the-art restoration performance, this increase in performance is often accompanied with undesired artifacts generated in their solution. These artifacts are usually specific to the type of neural network architecture, training, or test input image used for the inverse imaging problem at hand. In this paper, we propose a fast, efficient post-processing method for reducing these artifacts. Given a test input image and its known image formation model, we fine-tune the parameters of the trained network and iteratively update them using a data consistency loss. We show that in addition to being efficient and applicable to large variety of problems, our post-processing through fine-tuning approach enhances the solution originally provided by the neural network by maintaining its restoration quality while reducing the observed artifacts, as measured qualitatively and quantitatively.