Staff edit: For the most up-to-date information, please see the Sites and Sources wiki page.[/b]I see a fair amount of users uploading smaller or lesser-quality versions of images from Pixiv, Tumblr or Twitter. Every site has their idiosyncrasies. Even DeviantArt has users jump through a few hoops to get the best version of an image.As an archive of sorts, it doesn't do well to upload inferior versions of images when better ones are readily available.Be careful when uploading from a mobile device, as they are too bandwidth-conscious and sometimes compress images when uploading even on wifi.Use direct-link uploading on your mobile device instead. https://dl.dropboxusercontent.com/u/61512916/Direct-Links.png
Be sure to also include the submission page as a link as well. Some websites' file names don't always provide an artist name, and it's nice to be able to quickly comment/fav/reblog on the original submission.The higher the resolution, the better. Watch out for upscale edits, though. Try to be sure the biggest version of an image you find is unaltered from how the artist uploaded it.PNG preferred over JPG. But don't go editing JPGs into PNGs. It has to have been saved as a PNG by the artist from the start. If you cannot notice the difference between a high-quality JPG and a PNG, then I envy you.With two JPGs identical in resolution and content, go with the one with a larger file size. A smaller file size means more compression was used, so there is likely to be a difference in compression artifacts.Google Reverse Image Search is a very useful tool for finding original submission pages if you cannot identify an artist. https://images.google.com/ (Click the camera in the search box.)
SauceNAO mostly indexes Pixiv, Nijie, Gelbooru, and other sites that mostly specialize in images by Japanese artists. http://saucenao.com/
You can find plugins to integrate these tools into your browser's context menu so they pop up when you right-click an image.FurAffinity does not allow hi-resolution images without circumvention. It resizes images larger than 1280px upon uploading and compresses them into medium-quality JPGs. If an artist's FA gallery is full of 1280px JPGs, try one of their galleries elsewhere.You can't always trust images on FA if they're a maximum of 1280px. FurAffinity sometimes hosts PNG images that are clearly JPGs. Pretty silly to see an image in a lossless format with compression artifacts. Look closely: https://dl.dropboxusercontent.com/u/61512916/1440607298.seisuke_nerv_bea_clothed_-_copy_CLOSEUP.pngTumblr's hi-resolution images go to a maximum width of 1280px or a maximum height of 1920px (whichever comes first). Again, see if they have an alternate gallery and compare resolutions and formats.Twitter uploads are often made from mobile devices that are bandwidth-conscious and compress images before sending them. Unless you're getting PNGs, use another gallery if possible.Pixiv, InkBunny, and Weasyl do not have a limit on resolution. They are generally preferred if an artist also posts there.Pinterest is just plain awful when it comes to image compression and crediting the artist. If you find something there you want to post, but cannot identify the artist, try using Google Reverse Image Search or SauceNAO to find an original submission page.Tumblr requires you to click around. Sometimes users save and upload the "_500" preview versions.
http://kikurages.tumblr.com/post/124070968394/
http://41.media.tumblr.com/e5bd8ab6e8f5f3e31b4ca3862c6ce678/tumblr_nrhg39BG781spud3zo1_500.jpg
http://41.media.tumblr.com/e5bd8ab6e8f5f3e31b4ca3862c6ce678/tumblr_nrhg39BG781spud3zo1_1280.jpgTwitter is not as obvious. Most users save and upload the smallest version, as presented in the Tweet itself. It requires a little URL trick to get the full image. Right-click an image and copy its URL (FireFox and Chrome). Open a new tab, paste in the URL and append ":orig" to the end of it and hit Enter.
https://twitter.com/bethesda/status/607640799702949888
https://pbs.twimg.com/media/CG7GFHAVAAE6Xas.png The image as it appears in the Tweet.
https://pbs.twimg.com/media/CG7GFHAVAAE6Xas.png:large "Large" size presented to the user when they click on the image in the Tweet.
https://pbs.twimg.com/media/CG7GFHAVAAE6Xas.png:orig The image's unaltered size. It might not always be larger than the ":large", but always try for the ":orig".With Pivix's dynamically-resizing "manga mode" for multi-page submissions, users must click the arrows in the corner to full-view the images before saving. Otherwise they save preview versions whereas the full image may be larger and/or in a lossless or less-compressed format.
https://e621.net/post/show/709622
Full image is higher resolution, and clicking the arrows also gives it to you as a lossless PNG:
http://www.pixiv.net/member_illust.php?mode=manga&illust_id=48584322
http://i3.pixiv.net/c/1200x1200/img-master/img/2015/02/06/11/01/23/48584322_p0_master1200.jpg
http://i3.pixiv.net/img-original/img/2015/02/06/11/01/23/48584322_p0.pngPixiv Ugoira animations are just archives of JPGs played in Javascript. Run a bookmark containing "javascript:window.location = pixiv.context.ugokuIllustFullscreenData.src;" (without quotation marks) while viewing a Pixiv Animation to download the archive. There is also an online converter at http://ugoira.dataprocessingclub.org/ that gives you the choice of both WebM or GIF. It is more recommended to use the online converter because it maintains the framerate of the original submission. Most animations benefit better with WebM than GIF because the frames are already compressed from the start (archive of JPGs).DeviantArt submissions:
http://pre12.deviantart.net/0b88/th/pre/i/2015/120/3/6/otachi_by_zaggatar-d8rmmk7.jpg Normal: As it appears when you arrive to the page.
http://img08.deviantart.net/d180/i/2015/120/3/6/otachi_by_zaggatar-d8rmmk7.jpg Large: Click the image.
https://e621.net/post/show/666443/ Full: Click the DOWNLOAD button, if applicable. (Depends on if the artist enables it, I think.)Avoid using 3rd-party sources like Twicsy because it only hosts the ":large" images and converts everything into JPGs. Twicsy is still a very useful tool because it presents Tweets in a nice gallery format instead of that ridiculous infinitely-scrolling format that Twitter feeds use, so be sure to click around for a link to the original Tweet and snag the ":orig" file instead of saving the image from Twicsy itself. http://twicsy.com/u/usernametl;dr, I care too much about image quality preservation and am posting this so I/we can link users to it as needed.

You are a good man for doing this. *salutes*

Sticky plz! (btw, I already knew most of these methods but not the Twitter one. Thanks for sharing!)

Thanks for the info!
I didn't know about the arrow on multi-image Pixiv posts.

chdgs said:
Tumblr's hi-resolution images go to a minimum of 1280px or a maximum 1920px (whichever comes first).

Do you mean:
maximum width = 1280 pixels
maximum height = 1920 pixels

Pseudo-code:

if ((width > 1280) or (height > 1920) then
    image is resized to fit into a 1280x1920 "window"
end

chdgs said:
If you cannot notice the difference between a high-quality JPG and a PNG, then I envy you.

I hear this stuff all the time, and I have to ask: would you people happen to be cyborgs with a hundred times the visual acuity of the average human? Because I have 20/20 vision and I can barely tell the difference if they're shown side-by-side and pointed out to me.

i never bother with twitter actually. so i'll leave that to those who care about such social media stuff.

google reverse image search is indeed helpful but i've noticed that some times if the source ends up being from somewhere like pinterest then the results can get really screwy and show anything except what you're looking for.

that's also happened inexplicably on occasion for random pics as well as the thumbnail pic next to results (looking at you Deviantart >:( ) sometimes being very misleading and the link can lead to something entirely unrelated so watch out for these issues with google reverse search.

"crediting the artist", Pinterest isn't the only place that is terrible about this. i think everyone knows why i hate getting pics/info off rule34.paheal.

now what else was i going to say...oh, right. if you're getting pics off pixiv, check if the artist is here already by copy/pasting the artist name off pixiv into the search (name) bar here. if nothing comes up then put the japanese name from pixiv as the artist tag and add the translation request tag (this works for text in pics such as doujinshi as well as for getting names translated).

i'm sure theres a lot of pics around here with pixiv as the source but no artist tag on them at all.

Thank you for the comments. I know this wall of text doesn't look very appealing and I probably didn't arrange it as neat as it could be, but I'm glad some users are actually reading it and getting something from it. It's also a reference that I felt was needed, as I found myself repeating portions of it to other users.

Jugofthat said:
I already knew most of these methods but not the Twitter one. Thanks for sharing!)

It's probably the trickiest of the bunch because it requires playing with the URL instead of just clicking around.

I knew about the ":large" fix for quite some time. But learning about ":orig" blew my mind. Fortunately, when I went back to resave a lot of images, I found that not a lot of artists upload images that go beyond ":large" in their dimensions, but you should always snag the ":orig".

Munkelzahn said:
Thanks for the info!
I didn't know about the arrow on multi-image Pixiv posts.

It's where a lot of users seem to trip. Even if the "full" image isn't any higher in resolution, it could sometimes be a PNG or higher-quality JPG. So another pitfall of sorts is the notion that "it's not bigger [or lossless], so I won't bother to save the rest of the images in the set this way."

It's important to preserve the highest-quality version of an image that the artist makes publicly available.

Munkelzahn said:
[Tumblr]
Do you mean:
maximum width = 1280 pixels
maximum height = 1920 pixels

Yes! Thank you for the info. I only noticed that most hi-res Tumblr images seemed to top out at 1920px or bottom out 1280px and neglected to consider which dimension those corresponded with.

Fenrick said:
I hear this stuff all the time, and I have to ask: would you people happen to be cyborgs with a hundred times the visual acuity of the average human? Because I have 20/20 vision and I can barely tell the difference if they're shown side-by-side and pointed out to me.

My vision is terrible, but I just have a keen attention to detail and the first thing I look for in JPGs is the severity of compression artifacts.

Sometimes the difference in compression artifacts is very subtle even when you zoom in.
https://static1.e621.net/data/9c/a5/9ca5f29a512846f0f0f926922050ce71.jpg
http://40.media.tumblr.com/6b779e464e26d61528a0c84c155d3170/tumblr_nqo28pnUHl1su5akfo1_1280.jpg

I sometimes feel like I am overly anal about image quality preservation. To the point where some may view me as some sort of antagonist. "omg who cares??? enjoy the free porn" etc. I have received a few displeased notes from users who find me replacing their posts with bigger or better versions. Nothing personal, they're just doing it wrong and it is not necessarily their fault. I share what I know and they usually thank me for it.

treos said:
"crediting the artist", Pinterest isn't the only place that is terrible about this. i think everyone knows why i hate getting pics/info off rule34.paheal.

now what else was i going to say...oh, right. if you're getting pics off pixiv, check if the artist is here already by copy/pasting the artist name off pixiv into the search (name) bar here. if nothing comes up then put the japanese name from pixiv as the artist tag and add the translation request tag (this works for text in pics such as doujinshi as well as for getting names translated).

i'm sure theres a lot of pics around here with pixiv as the source but no artist tag on them at all.

Giving credit to the artist and sourcing to original submissions is extremely important. It's essentially the only thing that separates e621 from an art thief.

Non-unicode Japanese usernames from Pixiv tend to scare off a lot of uploaders from even trying. Fortunately, they usually also provide a source. If not, SauceNAO is very handy. (Should still tag as unknown_artist until a proper artist tag is applied, though.)

Fenrick said:
I hear this stuff all the time, and I have to ask: would you people happen to be cyborgs with a hundred times the visual acuity of the average human? Because I have 20/20 vision and I can barely tell the difference if they're shown side-by-side and pointed out to me.

It's hard to tell a difference between a TRULY high quality jpeg and a PNG unless you're looking for it. But if you know what to look for, and the image is a drawing instead of a real life picture, it's easy to see the artifacting in jpegs. In actual photographs, jpegs do a great job of hiding the artifacting in there normal camera noise, so it's difficult to see unless you zoom WAY in on something that has a solid color. But good luck seeing it in a tree.

Low quality JPEG compression is hard to miss for anyone though.

Also, I have shit vision,lol.

Fenrick said:
I hear this stuff all the time, and I have to ask: would you people happen to be cyborgs with a hundred times the visual acuity of the average human? Because I have 20/20 vision and I can barely tell the difference if they're shown side-by-side and pointed out to me.

Yeah, you need to know what you're looking for and at least at 100% quality the jpg artifacts get very, very small.

Past that, the signs are generally less color fidelity, and artifacts around drastic changes in color.
The best way to find artifacts is to zoom in a bit and, if possible, flip back and forth between the images.

If you're interested I made some neat comparison images and uploaded them to my Google Drive: [Link]
Remember to download the pictures and to view them at the original size and not fitted to the window or screen.

The main rule of thumb for me is 'don't upload JPGs that have large amount of consecutive red colors on them'. That's when there's no PNG alternative, of course.

Red screws up the compression, making artifacts look bigger than they should.

Found a cute little bug on FA for everybody trying to upload from FA.

The FA auto resize option for png above 1280px converts the file to jpg, but does not change the file-ending to jpg. This causes strange behavior in browsers and when saving, since the file is still marked as being a png, but is in actuality a jpg.

How do you know if this affects an image you're looking at? Try saving it, in Firefox the fake png gets saved as jpg, which is correct since it's actually one. I'd guess this behavior also happens in a number of other browsers.
Another good test is to try and open the file with Irfanview, if the program detects a mismatch between file-ending and actual image file it will show a warning and offer to rename the file for you.

Also, there is nothing that can be done from the outside, the artist would need to manually switch the bad submission file with the original png to get around this problem.

NotMeNotYou said:
If you're interested I made some neat comparison images and uploaded them to my Google Drive: [Link]

This was actually pretty helpful for me. Thank you.

This thread should be stickied. I just used it for Twitter.

Lance_Armstrong said:
This thread should be stickied. I just used it for Twitter.

I am glad other users are getting something out of this.

Though I still need to organize it into collapsible sections to make it more appealing to read. It's rather forbidding in its current appearance.

chdgs said:
Tumblr requires you to click around. Sometimes users save and upload the "_500" preview versions.
http://kikurages.tumblr.com/post/124070968394/
http://41.media.tumblr.com/e5bd8ab6e8f5f3e31b4ca3862c6ce678/tumblr_nrhg39BG781spud3zo1_500.jpg
http://41.media.tumblr.com/e5bd8ab6e8f5f3e31b4ca3862c6ce678/tumblr_nrhg39BG781spud3zo1_1280.jpg

I use this achy-breaky tampermonkey script for that: http://userscripts.softhyena.com/tumblrautofull.js

i feel as if i've seen this kind of thread several times now. why not sticky and update it as needed?

If the image has text, that's what I'll compare first. I find it easier to match up (on a mobile device) and since text usually has a background that contrasts it (e.g., black on white) any compression artifacts or saturation difference tends to be a lot more obvious (particularly round shapes and narrow triangles, both of which are common in text).

I'll bring up stickying this thread with the committee. We may need to move some stuff around as the forums are already kind of sticky-y as it is.

Now with more sticky'd.

Thanks chdgs for putting this together for us. :)

chdgs said:
Pixiv, InkBunny, and Weasyl do not have a limit on resolution. They are generally preferred if an artist also posts there.

Let me tell you a little anecdote...

Many people upload preview versions from Inkbunny (width = 920 pixels), because they don't know that clicking "max. preview" gives them the full version.
So in May 2014, I opened a support ticket on Inkbunny, with this suggestion:

Requested feature:
When you download a preview image from Inkbunny, and there's a "max. preview" version available, Inkbunny could display a warning along the lines of "The image you're trying to download is only a preview, click 'max. preview' under the image to download the full version".
Example:
post: https://inkbunny.net/submissionview.php?id=594214
preview image: https://inkbunny.net///files/screen/780/780613_Syntex_kinggamekeeper_commission.png (920x613 pixels - 471,147 bytes)
full image: https://inkbunny.net///files/full/780/780613_Syntex_kinggamekeeper_commission.png (3000x2000 pixels - 2,929,964 bytes)

Why it would be useful:
When people repost images from Inkbunny, they often use the preview image, probably because they're unaware that there's a bigger version.
Examples:
https://e621.net/post/index/1/source:inkbunny%20bigger_version_at_the_source

The response I got from the "Inkbunny Support Team" three weeks later:

Hmm. So you're saying that people who are viewing illegally-distributed copies of artwork posted to Inkbunny have to come to Inkbunny to get the full version?

This seems like more of a feature than a bug to me . . .

Sofurry seems to have no resolution limit, the two posts I uploaded (as of writing this) are both from sofurry (note the source) and are way over 1080p.

I suppose this probably almost never happens (a file 0.1MiB too large), but iO9 uploaded a huge Zootopia cityscape. It turns out the insanely highly-detailed image is 0.1MiB too large to post. What should be done in choosing something to upload in this kind of situation where the next largest is much smaller, or should I not have been trying to upload it to begin with?

Here is the direct link, but I'm not sure if that works since it was not allowed for direct upload when I tried.

It's the final image here in this link.

I almost didn't bother asking about this, but I have seen official materials posted before for stuff and that one is exceptionally detailed. It made me immediately think of the absurd_res tag.

Zeopard said:

Here is the direct link, but I'm not sure if that works since it was not allowed for direct upload when I tried.

It's the final image here in this link.

I admit, this doesn't help solve the main issue here, (what to do when a file size is just barely above our upload limits).

But I just realised that this image in specific probably wouldn't work out here anyways. We do have some scenic images from awhile ago when our approval policy was a little more relaxed than it is now. But currently a scenic shot of a distant city, no matter how beautifully made, probably wouldn't be relevant enough to stay. Not unless it had some animals/anthropomorphic creatures prominently visible. So at least in this one case, it may be just as well.

heres another site for the list. luscious.net

see the source for post #829072

i just replaced the smaller version as it was the preview version of the pic (much like with inkbunny pics). might want to point out the rather small download icon under the pic which should be clicked to get the full size version of the pic in question.

furrypickle said:
I admit, this doesn't help solve the main issue here, (what to do when a file size is just barely above our upload limits).

But I just realised that this image in specific probably wouldn't work out here anyways. We do have some scenic images from awhile ago when our approval policy was a little more relaxed than it is now. But currently a scenic shot of a distant city, no matter how beautifully made, probably wouldn't be relevant enough to stay. Not unless it had some animals/anthropomorphic creatures prominently visible. So at least in this one case, it may be just as well.

Ah yes, I forgot the "tag what you see" aspect and I didn't read the rules closely enough about cities and such. Thanks.

Inkbunny has improved in such that wide preview, download and link in image itself are all to "full" url instead of "screen".
However it should still be noted that with some, especially with small gifs it's still possible to accidently get inkbunnys generated "screen" preview version of image as those do not have download link, no link on image and it loads "screen" version unless user has "wide" preview selected (which has to be selected from bottom as clicking image won't work with small images). Also with gif and jpg images it usually means lower quality with larger filesize, even if resolution and filetype are identical. This is also why with inkbunny dublicates should be threated carefully as larger files are actually lower quality ones!

I have been trying to figure this out for couple days now, does twitter store gif files somewhere? Right now it seems like they simply convert gifs into videos and just use the video file, then disable right click context menu so users do not even try to save them. As they are stored in entirely differend URL from photos as well and converting things back into gif will be bit painful because of video compression.

Update (forum #235250): "_1280" should be replaced with "_raw", it allows you to access images larger than 1280x1920. This ought to be updated too.