Transitive Learning: Exploring the Transitivity of Degradations for Blind Super-Resolution

Being extremely dependent on the iterative estimation and correction of data or models, the existing blind super-resolution (SR) methods are generally time-consuming and less effective. To address it, this paper proposes a transitive learning method for blind SR using an end-to-end network without any additional iterations in inference. To begin with, we analyze and demonstrate the transitivity of degradations, including the widely used additive and convolutive degradations. We then propose a novel Transitive Learning method for blind Super-Resolution on transitive degradations (TLSR), by adaptively inferring a transitive transformation function to solve the unknown degradations without any iterative operations in inference. Specifically, the end-to-end TLSR network consists of a degree of transitivity (DoT) estimation network, a homogeneous feature extraction network, and a transitive learning module. Quantitative and qualitative evaluations on blind SR tasks demonstrate that the proposed TLSR achieves superior performance and consumes less time against the state-of-the-art blind SR methods. The code is available at https://github.com/YuanfeiHuang/TLSR.