delet upscale

Considering the uploader, I'd say it's more likely overfiltered than upscaled

The original is probably this - https://twitter.com/FateGrandOrder/status/1073914792711139328
Then it was reuploaded and reupscaled again and again - https://twitter.com/karoshimyriad/status/1074542823339286537?lang=en

This is can't be "overfiltered" because it's clearly not a scan, but a digital picture. And artifacts are the exact ones you'd expect from waifu2x. I would've expected regulars here to have a better eye for things like this.

Hell , the original image of 1010 x 710 pixels has far more detail than this one with absurd res. Its not just upscale, its a bad upscale.

>Clearly not a scan

Just compared it to your digital sample, I can already see lots of imperfections that likely resulted from scanning.

The aspect ratio is slightly distorted;
the pure color or perfect gradient become uneven (particularly on her face);
and lots of details on darker areas are lost.

None of these will happen in simple upscaling no matter how bad your algorithm is.

>Hell , the original image of 1010 x 710 pixels has far more detail than this one with absurd res

That exactly proves it's a scan? How else are you going to lose details by upscaling? You are just going to make them bigger.

Actually, almost all the scans have fewer details than digital source, regardless of dimension: scanning is a very "lossy" process especially if the printing quality is low and the material is bad.

People like the uploader (he has been around forever so I knew) like to scan the material at unnecessarily high DPI and then run some very heavy filters on it to fully get rid of the screening, but the cost is the whole image become something like this. Yes, it is bad, but it's not upscaling

(Well, in a sense, scanning at higher DPI than printing DPI is a kind of "upscaling", but that's beside the point.)

In this particular case, the original material is a イラストカード (illust card), which is perhaps only in a size of a postcard, which is 100 x 148mm in Japan. So, 100mm (~4") becomes 5388px, which means it was scanned at 1200+ dpi, of course it's going to look like shit after processing.

I just scanned a postcard at 1200 dpi for you:



You can see how huge the screening pattern would be at this resolution. To remove them all (which I don't think is necessary), you need to run some very heavy filters and the result would be blurry (mine is relatively conservative as I always advocate).

the exact size of this thing is A5 (148mm x 210mm). That said, the paper is heavily textured.

Here's my own scan if anyone want to clean it up or whatever. 600dpi, no color correction, no filtering.

Thanks for making sound arguments and going through effort to show some evidence.
First of all, i doubt Yamato bomber is author of this upscale. There were upscales of this digital image way before the date this was posted here.
There are other signs this is not a scan, the colors and luma are all exactly the same as digital image - its possible to adjust to get it close, but it's extremely hard to get it to be exact match.

The way an upscale would lose detail is through denoise - this is one of the great things about waifu2x, and there are several levels and algorithms. But that upscaling often introduces trademark upscaling - which is more noticable the more you do it.

So to prove a point i took the "original" image and upscaled it, so you can compare the artifacts.

(CUnet)(noise_scale)(Level3)(x4.000000)
(RGB)(noise_scale)(Level3)(x4.000000)
(UpResnet10)(noise_scale)(Level3)(x4.000000)

The artifacts are similar, there isnt any more detail in the OPs image, there is just no way it is a scan. The image contains a lot more detail that would be discernible if it was a scan. If it was filtered like yours, it would've had triple the detail and have more accurate shapes.
All my examples are better probably because i used better sources/better models/more lossless processes. But i probably wouldnt even do it this way for the best result.

Anyway, with some reverse searching i did find this image which i guess ill upload, which is the real deal.
Please make adjustments that are necessary, im not really active user.

Also offtopic, i also found these -
4092x2557 dark sakura
lower res, but has the "not for sale" text

They are lower quality jpeg so not sure if i should upload. Though a denoise only function with waifu2x could fix up most of the artifacts.
Im guessing a higher quality version must be floating around, but i couldn't find it. I dont really know what the official source is for any of this, i found them on some chinese forums (like bilibili).

This dark sakura also has upscales like the one with Saber floating around like this one

Isn't that clearly upscaled?, I mean, just to look at the glove coat is possible to perceive, it's kind of "blurry", of when a image is small and you use noise reduction while upscaling, apart from that, basically in the whole image it is possible to realize that it was upscaled, the amount of detail lost is insane, I don't understand much of scan, but this image and the original has exactly the same colors, is it possible? and a scan would lose so much detail like that?, comparing with the post #569346 gets easier easy to perceive.

I only read the first 2 comments, the others was too long.

Well, it can't be scanned because the printed version has much smaller field of view..

I stand corrected