: The "4x" indicates a four-fold increase in total pixel count, often using interpolation or AI to fill in detail.
: A specific file for "Enhanced Super-Resolution Generative Adversarial Networks" used by digital artists to upscale old photos or low-res art. 2k-2-4x.rar
: Used in games like Skyrim or Minecraft to replace blurry original textures with sharp 4K versions. : The "4x" indicates a four-fold increase in