Kind of alarming to see this being proposed as an investigative tool. Isn't the entire point of this area of image processing that the network is creating plausible information where there is none? That's great for creating higher-resolution versions of entertainment assets, but it would seem categorically inappropriate for forensic science.

Exactly. It's not extracting information, it is (as the Boston Marathon link says) hallucinating the additional information. It's an artist's impression, not CSI's magic 'enhance'.

In terms of the danger of this kind of image confabulation, it seems similar to the block-based compression on Xerox photocopiers which sometimes changed numbers in scanned documents: http://www.dkriesel.com/en/blog/2013/0802_xerox-workcentres_...

I expected that to be a 1970s computing shanty but D.Kriesel spotted it in 2013 and it took until 2015 to get it properly patched. Incredible.

> it would seem categorically inappropriate for forensic science

It would be absolutely wrong use, as it substitutes some information that the software has learned before and combined instead of the non-existing one in the original pixels.

If the software was trained with the picture of the innocent person, it would produce it instead of the picture of the really guilty person. It can only guess and only guess based on with what it was trained with.

It's bad enough when people don't notice that they filled in the gaps based on pure speculation and prejudice, it will be even worse when the same happens with the "authority" of a computer.

Maybe there could be a moral obligation for the designers of the training set: trained with the right data, if you say "enhance" once too often the model might overfit into a scene from Star Trek ("after shooting, video footage shows man in command uniform firing at random redshirts, people in medical uniforms miraculously unharmed").

However, it is possible to extract high-resolution images from multiple frames of low-resolution video.

Yep. Happens because the phase of the sampling grid changes on different frames, which effectively increases resolution.

Definitely glad to see Waifu2x mentioned here, in the age of increasingly common paywalled full-resolution "imagery" (ahem..), it's a godsend to anyone who isn't using a monitor from the early 00's.

It's also nice to just add a little extra quality to older... imagery. Works surprisingly well for non-2D stuff too.