Waifu2x ( http://waifu2x.udp.jp/ ) is a service that uses neural network shape-recognition to resize images smoother than the classic methods of sinusoidal or cubic interpolation, etc.

I know (or at least thought?) the goal of e621 is to have the largest, most high-quality image possible straight from the source (artist-final version of the image), but this program can generate images that SEEM larger and more detailed, but are simply dynamically resized to keep their features and curves intact while appearing to have a larger resolution

I think we need a precedent to decide whether images processed in this way are allowed to replace their source counterparts. My vote goes for no, because even though it makes the image larger, and is usually unnoticable to the human eye, it's not actually gaining quality, and doesn't create any new information.

On the one hand, the tool could be used to bump very small images up to a size that better matches the rest of the content on the site (IE to around 1280 pixels on either side or so), but at that point it's not really a source file from the artist themselves

I was assuming the final answer would be no because it's not a proper source file, but it's nice to have a final answer when it comes to things like this, so if people in the future start to upload files processed with this, we know what to do with those files. The resizing does seem to be pretty good quality, but with very small images or pixel art, you start to notice artifacts that make it obvious the file has been resized (think of those filters people put over nes games to make them look smoother in hi-def, it pretty much looks just like that)

anyway, yes or no? should these processed files be allowed to replace source files as a larger resolution file?

( http://i.imgur.com/XF6h2gM.png ) here is an example of the artifacts you get when you process very small images, I've run one of my doodles (150 x 150) through the site twice, and you can see it tried its best, but couldn't keep the curves as well as one might hope

Yeah, no on this, we regularly delete artificially upscaled images and will continue to do so.

sounds good to me

I think we can't do this because it's still technically tinkering with someone else's images in the same sense as edits (which are mostly only tolerated because at least they bring something new to the table).

But I do have to say, just saying "Didn't read lol we dont do upscaled images go away" (don't know if it was intended like that, but it seemed a bit curt) isn't really doing enough justice to this neat little piece of free software. Because it really seems to work quite beautifully on simple images, especially monochromes or flat colors. With more complex art you're bound to get at least some of that filtered '2xSai emulator look', but would you just look what it did to this:

post #460221

I upscaled it to twice its size, once through Waifu2x, then through Firefox itself (and printscreened that) for comparison.

http://i.imgur.com/U66Ozm7.png (Firefox)
http://i.imgur.com/3hIdkTq.png (Waifu)

That's amazing! Put it next to the original lineart, it seriously doesn't appear like it was artifically upscaled at all. That deserves at least some acknowledgement.

So thanks for sharing, even if we can't exactly use it here. I know I will. :)

This is a pretty high quality upscaler. I'm gonna bookmark it for when my sketch scans are too low-res and I need a high-res version.

But yeah, an upscaler would have to go beyond simply making very clever inferences from the original pixels.. there is this same issue with scale that I've encountered with all upscalers -- basically, that the same detail size, when upscaled, can feel quite different. The more the upscale factor is, the more noticable this is. A detail level that looked quite good on a smaller picture can seem coarse or crude on a larger picture.

I think it's important for image boards to retain the original image. If viewers think the image is too small, then let them resize it themselves.