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underanalyzeron Differentiable Dithering

Although I agree with the sentiment I am going to point out for fun that the algorithm does not have to assign probabilities less than 1. Technically a solution like Floyd steinberg produces is in the search space. You would just need the right objective to motivate it

underanalyzeron When Math Gets Impossibly Hard

It’s sufficient but not necessary. Consider a trivial example with three nodes arranged in a chain. The edge nodes at the end of the chain both have degree 1 but walking from one edge to another is an eulerian path.

underanalyzeron Differentiable Dithering

That's interesting! One thing I was surprised about is that they don't address optimizing the palette and dither pattern across time (b/c most gifs are animated). This feels to me like it would be really interesting and a hard problem for traditional algorithms. They do mention it as a possibility for future work at the end tho. They also seem to have separate losses for the palette net and the dither net instead of just adjusting both to optimize a general image quality metric (although it does look like they have some kind of perceptual loss, it's just not the only objective)

underanalyzeron Differentiable Dithering

Wow exciting! I tried to use ditherit to get some baseline comparison images for my post! Is there anyway to both control the number of colors in the palette and have it auto pick colors at the same time?

underanalyzeron Differentiable Dithering

Sorry I could have been more specific. By more optimized jpeg I meant better perceptual quality (again subjective) within the confines of what a jpeg decoder could understand.

To co opt your knobs analogy I imagine each of the steps of a complex image compression pipeline comes with its own knobs each with its own tradeoffs. The dream here would be to tune all those knobs at the same time to optimize some sense of quality in a particular image. Of course huge disclaimer I’m not an image or signal processing expert. It’s also very possible that these “knobs” have been tuned well enough so that even if we optimized them for a specific image the quality difference would not be noticeable.

underanalyzeron Differentiable Dithering

Yea neural image compression looks pretty neat! The reason I bring up jpeg is because it's so well established and if you come up with a more optimized jpeg (which I'm not really convinced is possible, again a pipedream) you don't have to force people to transition to a new image format. In the end methods like neural style or whatever comes after are probably the better pick but there is a transition period.

underanalyzeron Differentiable Dithering

This blew up while I was asleep so I’ll try my best to answer now!

1. Yes the palette is being optimized for as well which is imho what makes it different from a quantization approach 2. That’s a good point. I cite a reference blog post which does use blur in the loss function towards the end of the post. Unfortunately I think pure blur would still produce a noisy image as it would remove variance in the eyes of the loss function but not the final image. I would guess something like the example I give with purple, red, blue pixels would still be a problem for blurred loss

underanalyzeron How we learnt to stop worrying and love web scraping

The article seems to recommend using an api if possible.

underanalyzeron Essential C (2003) [pdf]

Now then, isn't that nicer? (editorial) Build programs that do something cool rather than programs which flex the language's syntax. Syntax -- who cares?

Although some feel like it’s too opinionated to belong in this article I really appreciated the above. Edit To be clear the author is advocating for simpler syntax here to increase program readability. This could be taken other ways.

underanalyzeron Speculating on the Animal Crossing Turnip Market

Afaik the 1/e solution is only optimal when you don't know anything about the distribution being draw from (but also why it's amazing). Since the author knows the probability distribution the prices are being draw from you can do much better with a little dynamic programming.

underanalyzeron Show HN: I made a neural net that analyzes privacy policies

Very cool idea! One question I couldn’t seem to find the answer to on your site was are the policies featured on your a/b training exercise distinct from the polices that the ai grades? For example will a user going through your a/b trainer ever see a snippet from the Instagram privacy policy?