Topic: How can I upload an image that is only 250 pixels wide?

https://www.pixiv.net/artworks/517844 I want to upload this.

well the guidlines only say images less than 256 will likely be deleted. doesn't sound like they'll all definitely be deleted

probably depends on the content in the image. if it looks like poo then yeah that would increase the chance of deletifying

post it and see if it makes the cut. in my opinion it looks pretty good

It should be fine if you upscale it sensibly.

From the uploading guidelines:

Sensible integer upscaling with nearest neighbor (a.k.a. without smoothing filters) is permitted for pixel artwork that would otherwise be too small to see well.

fliphook said:
well the guidlines only say images less than 256 will likely be deleted. doesn't sound like they'll all definitely be deleted

probably depends on the content in the image. if it looks like poo then yeah that would increase the chance of deletifying

post it and see if it makes the cut. in my opinion it looks pretty good

Anything below 256 in either direction straight up cannot be uploaded

https://github.com/e621ng/e621ng/blob/c4e8bbd7e3b5eb1cd11723f9a2e432325d7dc637/config/danbooru_default_config.rb#L124-L126
https://github.com/e621ng/e621ng/blob/c4e8bbd7e3b5eb1cd11723f9a2e432325d7dc637/app/logical/file_validator.rb#L64-L68

eightoflakes said:
It should be fine if you upscale it sensibly.

Yeah, it should be upscaled, but not in a way that makes it a blurry mess, and also not excessively (i.e. don't blow it up to 2000 in width), do as little upscaling as you need to for it to be uploadable

donovan_dmc said:
Yeah, it should be upscaled, but not in a way that makes it a blurry mess, and also not excessively (i.e. don't blow it up to 2000 in width), do as little upscaling as you need to for it to be uploadable

Ideally this image needs a 2x scale, which would make it very much large enough at 500x700. Feels a little excessive to 2x an image that's only 6 pixels away from meeting the requirement... but any non-integer scaling is going to result in mixels.

Yeah, the change to requirement became a thing once we got WebP thumbnails on the site, where the thumbnail sizes were also increased - update that has been heavily requested for eternity.

It's othervice acceptable and source is PNG so you do not have to worry about anything extra.
Basically upscale it nearest neighbor aka no interpolation, 2x or 200% and upload.
My problem with this is that I have seen what users do and even something as simple as this can be fucked up really royally, so if you don't have confidence just say so and I can do it.

faucet said:
mixels.

I do not know if I love or hate this term.
Non-square pixels or inconsistant pixels I have mostly used.

faucet said:
any non-integer scaling is going to result in mixels.

mairo said:
I do not know if I love or hate this term.
Non-square pixels or inconsistant pixels I have mostly used.

I thought that "mixels" was more used to refer to different elements in a work (usually a video game) having significantly diffrent pixel resolutions.

I think the artifacts caused by non-integer scaling is more often just called warping (or in animation "shimmer").

dba_afish said:
I thought that "mixels" was more used to refer to different elements in a work (usually a video game) having significantly diffrent pixel resolutions.

I think the artifacts caused by non-integer scaling is more often just called warping (or in animation "shimmer").

Aliasing?

Considering the OP is banned, I guess I'll upload the example they gave.
post #6049736

alphamule said:
Aliasing?

No.

Aliasing is somewhat hard to define fully, but it's essentially artifact you get when you sample something. Best example and useage of the word is from gaming, the 3D enviroments triangles are infinite, but when you render those to your screens resolution, sometimes the screens pixel hits the triangle, the next pixel doesn't, where you get the stairstep effect on edges.
When talking of artwork, this generally applies to when there's similar restrictions of color palette and/or resolution. You have linework, but you do not have colors or resolution, to make it smooth. You get aliasing, but that artifact comes from the limitations put in place.

Problem is that modern screen resolutions are extremely high, so to see a single pixel on artwork you have to use magnifying glass, where 20-30 years ago you could tell where pixel is even from your NES on CRT. Nowdays you have to upscale them to be visible on modern resolutions, hence why the pixels are deemed even more square than usual, but that's only good way to actually show them nowdays.

But we are not talking about pixels being sharp or square here, we are talking when pixels are upscaled using non-integer values, which causes perfectly square 1x1px to be e.g. 2x3px, which skews how the image should look and with animations you will get temporar instability as well. It makes things look wobbly and like there's some checkboard pattern on top of the image you can outline.

It reminds me of extruded metal (which is a process to generate a ventilated metal plate by first cutting lines in it and then stretching it along one axis). But 'extruded pixels' is also not terribly evocative IMO.

"Latticing"?

Upsampling and Downsampling are good words to know, because image editors often try to present 'scaling algorithm' as one thing that can be applied for scaling up and scaling down, but that's completely false; When downsampling, you look at N source pixels and generate 1 output pixel (for example, via taking the weighted average of an area). Aliasing always happen during downsampling (though it is not always obvious).
Faster downsampling algorithms tend to generate more obvious aliasing because they take 'a representative sample' of pixels rather than taking all pixels in the area into account.

The name given in 'Scale Image' type of dialog is usually in fact an indicator of what algorithm will be used to upsample (examine typically 4 source pixels to generate >4 output pixels). Upsampling can cause artefacts (eg. latticing), but can never cause actual aliasing.

(of course, each dimension is independent. Squash+Stretch type animation will be upsampling one dimension while downsampling the other, so you can have every possible artefact at once! Just some of them will be along one dimension, and the others on the other dimension.)