Re:Removing blur from images – deconvolution and using simpl...
by ardourdev on Friday May 27, 2022 @08:13AM
(#31528623)
Look up computer generated holography! It is certainly possible to calculate a hologram of a letter which focuses at some different depth than the screen.
There are issues which arise from restricting the hologram to a real valued grid, like limited FoV and noise, but these are not impossible problems to solve and existing technology is already quite good in terms of image quality.
Convolution smooths out functions. If you convolve any function with a Gaussian kernel, you get a C^infinity function (a function that has continuous derivatives of arbitrary order).
This anti-blurring effect would attempt to find for a given function f another function g so that g convolved with a Gaussian kernel is f. But if f is discontinuous no such function exists.
This is not just academic. Letters on a screen are discontinuous functions.
You could say that a certain amount of smoothness is tolerated. Or that all signals are discretized anyway, so the whole concept of continuity is mathematical non-sense.
So, what I provided is just heuristics, is not a solid proof. It's still in principle possible to produce such a anti-blurring algorithm, I just find it highly unlikely, I would not invest much time in it.