UltraSR: Spatial Encoding is a Missing Key for Implicit Image Function-based Arbitrary-Scale Super-Resolution. (arXiv:2103.12716v2 [cs.CV] UPDATED)

The recent success of NeRF and other related implicit neural representation
methods has opened a new path for continuous image representation, where pixel
values no longer need to be looked up from stored discrete 2D arrays but can be
inferred from neural network models on a continuous spatial domain. Although
the recent work LIIF has demonstrated that such novel approaches can achieve
good performance on the arbitrary-scale super-resolution task, their upscaled
images frequently show structural distortion due to the inaccurate …

arxiv cv encoding function image scale