The idea is to take old games without modifying them, but have the graphics card apply a series of filters to their output before sending them to the monitor. A very crude example would be to take a game that has a resolution of 640x480 and do:

• Increase the resolution to 1280x960
• Apply a blur (low pass filter)
• Apply a sharpen (1 + high pass filter)

These steps may not necessarily be the best to improve the visuals of an old game, but there are a lot of techniques that are well-known in image processing for this purpose.

The question is, do the (NVidia) graphics cards give the ability to load a program that modifies the screen before sending it to the monitor? If so, how are they called and what terminology should I use to search? I would be comfortable with doing the programming myself if this ability is part of a library.

Also, would the solution be different between Windows and Linux? If so, either is fine, since most of the games are probably runnable by wine.