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Comment by rcarmo | Hacker News Reader

I was instantly reminded of this “pineapple”:

https://twitter.com/cassmarketos/status/1229473344480673792?...

Of course, an actual working compression algorithm is quite likely. I recall that recently someone was upscaling and colorizing ancient movie reels to modern standards, and there is plenty of low-hanging fruit in fine-tuning parameters to suit specific images, so I actually look forward to this.

I just hope they don’t name it JPEG2020, JPEG2000 was a bit of a dud.

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I don't know how recolorization algos work, but a month or so ago, I saw this old 1900s image of a new York street that was colorized on reddit. Everyone on the thread was commenting about how there was so much violet hue in every single person's dress in the photo. Iirc that recolorization was done by a neural net too.

Then I realised what must've happened. There were tons of open air carts on the street selling eggplant. My guess is that the NN was either shown that or recognized that part of the image and colored almost everything else it saw using that as its base point. Not the best technique.

Jpeg2000 was a dud because of licensing and patents, not having a year in the name.

...and performance (or lack thereof) --- AFAIK the baseline J2K was always implementable freely (similar to the situation with JPEG; arithmetic compression was specified but largely unimplemented due to patents, while baseline JPEG was supposed to be free), but the abysmal performance relative to JPEG for a minor increase in compression efficiency, along with the surprising amount of complexity in the spec, made it a poor choice.

There are lots of scanned ebooks on archive.org that use J2K compression, and the sluggishness when turning pages is extremely noticeable compared to others which use normal JPEG.

DeOldify [1] by Jason Antic got really good results with old photos and movies colorization.

[1] https://github.com/jantic/DeOldify

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