Since, you mention gamma, I have to link this: http://www.ericbrasseur.org/gamma.html?i=1 http://www.ericbrasseur.org/gamma.html?i=1 Also, side-by-side compari

Since, you mention gamma, I have to link this: http://www.ericbrasseur.org/gamma.html?i=1 http://www.ericbrasseur.org/gamma.html?i=1 Also, side-by-side comparisons are hard, its best to flip back and forth between the two images, like opening them in an image viewer and pressing arrow keys. Or cross eyes like with magic eye stereograms so you see them "layered". But yes, more fundamentally, I think you're right that this is not really image content dependent, it doesn't need any image prior, if all you want is to minimize means squared error after upscaling with a fixed bicubic interpolation.