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I think I've got a twitch now, when I think about this. How those stupid moviemakers would say, "enhance!" and I (along with many of my geek brethren) were like, "there are no more pixels, that can't be done!"

And now it exists. "Enhance" exists.




Or does it? If you enhance security footage to make a barely visible face recognizable it will make it but it won't be the person in the footage anymore.


It does not exist. The AI models generate "what could be" instead of "what was", i.e. they hallucinate heavily in upscale tasks.


> It does not exist.

The MRI scanner near you is potentially using AI to increase image signal, then to increase pixel count 4x (well, 2x in X direction, 2x in Y direction. Potentially also generating a slice between each slice in 3D datasets).

If you turn off the AI and actually acquire the information, the scan is long, the patient moves and it is blurry. However if the patient is still, the non AI images look like the AI images.

Disagreeing with it is sort of moot now - it’s in the machines and is running. It works well, I’ve been using it daily for a few years.

All vendors have it - I use the Siemens product ‘Deep Resolve’ [1]. Their PR department undersells it, in my view this is a bigger change than the 1.5T to 3T transition.

[1] https://www.siemens-healthineers.com/magnetic-resonance-imag...


The scanner is faster because it collect less data.

The image is sharper because it have more data.

Where did the missing data came from?

It came from the training data set, not the patient.

No matter how good the image look like, it is not something from from the patient.


Yet, it can be "close enough" for horseshoes, hand grenades, and surgery.


Which may well be, but those detectives still aren't going to suddenly be able to read the license plate from an "enhanced" blurry photo, like their TV counterparts were doing back in the early 00s.


Not necessarily. As long as some mashed pixels of the license plate remain, and assuming different license plates would result in differently mashed pixels, it might be possible to restore the original from the highly compressed image data.


From series of images, aka. video, sure. From a single image? Not so much.

In video there is a lot of temporal information and even if the spatial resolution wasn't high enough in a single image, one would be able to accumulate a higher resolution version of the scene using multiple observations.


Correct. And the extrapolation region for the MRI is reasonable, I reckon, versus extrapolation into pulling enhanced blurry photos!


If the model learns that it can get fundamentally the same information from a lower res scan then it’s moot though.


Some of this can be done without AI as well: https://en.wikipedia.org/wiki/Compressed_sensing


We have 7T at my old uni in Alabama


It would be really interesting to see what it upscales poor security footage to be when we know the people in the picture; how accurate was it?


The models usually bundled with ESRGAN don't enhance like CSI. They straighten lines and jpeg blocking a little and correct "subatomic" details, but cannot restore large areas like faces, objects, etc. It's more of an AI-flavored "Effects - Sharpen" than stereotypical "Enhance!".



The better example of "Enhance!" still remains this piece of software: https://www.youtube.com/watch?v=19wgu5GZDhk




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