Tuning Parameter Selection for Sentinel-2 Sharpening Using Wald's Protocol

In recent years numerous model-based methods for super-resolution of Sentinel-2 (S2) multispectral images have been suggested. Super-resolution aims to enhance the resolution of a captured image by upscaling and enhancing the details. The performance of model-based methods relies on carefully selecting regularizers and tuning parameters. This paper investigates whether using Wald's protocol, i.e., selecting tuning parameters at reduced-resolution, translates to a good performance at a full-scale. To investigate this, we use the recently proposed S2Sharp method and show that selecting its tuning parameters using Wald's protocol improves its performance.