Upscaling algorithms vary from the extremely basic to the ML models we see today that straight up replaces or adds new details. Some of the more naive algorithm

Upscaling algorithms vary from the extremely basic to the ML models we see today that straight up replaces or adds new details. Some of the more naive algorithms do indeed just look blurry. https://en.wikipedia.org/wiki/Comparison_gallery_of_image_scaling_algorithms https://en.wikipedia.org/wiki/Comparison_gallery_of_image_sc...