# Limit size of pictures

Every now and then we get posts with ridiculously large pictures in them. Case in point:

from this question. That's a 5 megapixel photograph, and I guess we should be glad that OP doesn't have a Hasselblad H4D-200MS, or it would have been a 200 megapixel picture. I scaled the picture down to 1 % of its original size:

and lo and behold!, no information seems to be lost. Even after throwing away 99 % of the image.

OK this is a very unsharp image, but what if there's a detail that matters? Well, crop the picture to that detail, and post that. If you think the total image is relevant as well, then post a scaled down version of it, 640 x 480 is more than enough.

Suggestion: limit uploaded images to 1 megapixel.

• I seem to remember a few cases where the details on the board were the target of the pictures. Maybe require that the user marks why they need higher – Kortuk Jul 28 '12 at 10:38
• Don't limit what people can upload. Resize them after they've been uploaded. – endolith Jul 28 '12 at 18:17
• @endolith - to have the original as yet another useless image on imgur? When I post something I think it's my duty to see that it's properly formatted, not something I would leave to other to fix it for me. – stevenvh Jul 28 '12 at 18:23
• If deeper details are required, they can upload the full-size image to Imgur, then post a smaller size in-line with a link to the full-size version. 640 wide is about the maximum that will fit in-line anyway for most readers. – The Photon Jul 28 '12 at 19:10
• I agree that 5 megapixels is way too much, and it could cause some with low bandwidth problems (I'd hate to load that page on dial up :-) ) Maybe there should be a reasonable limit, or at least a popup asking you if you are sure you want to keep it at that size (many people who do this are probably not aware of the issue) Even with very detailed PCB pictures, I can't see why you would ever need more than 1MP. – Oli Glaser Jul 29 '12 at 8:09
• Thanks Oli. If you support this don't forget to upvote. With the current +1/-1 I'm getting nowhere :-). (BTW, "Oli" is that an "Oliver" who ran out of memory?) – stevenvh Jul 29 '12 at 8:14
• Sorry, I forgot to upvote before - done now. You guessed right, I'm formally an "Oliver" :-) – Oli Glaser Jul 29 '12 at 19:11
• @ThePhoton - I agree. A far as I can tell, the site css limits the image width to 630px so the 5Mpx image in the question appears as 300kpx. On rare occasions I save a local copy of an image if I need to see more detail but your suggestion seems the most sensible way. – MikeJ-UK Jul 30 '12 at 12:32
• I don't agree that the system should automatically limit picture sizes because there are occasional good reasons for a large picture. However the majority are just from lazy people that upload their poorly focused camera pictures directly. We should be telling them up front that is not acceptable, then leaving comments and downvoting when they do it anyway. – Olin Lathrop Jul 30 '12 at 14:39
• How about automatically creating a thumbnail to a normalized size that loads fast (and cheap for mobile users!) and make the thumbnail clickable to open the full size image. The full size image can easily be scrapped from the servers when there is a click/view ratio of say 1:20 (less than one click per 20 views? then remove the full size image) – jippie Jul 30 '12 at 19:09
• Mind you, people uploading huge images usually are unaware of the problem they cause for other users or how to improve it. If the huge-image-poster was on a 'pay per use low bandwidth' mobile service, (s)he would probably quickly learn how this resizing thing works. There appears to be no need for the user to resize, so why bother? And as stated before, lots of people just don't know how to fiddle with images like many of us so easily do. In conclusion: I (hypothetically me) have no problem, don't know what these resizing-people are talking about anyway, so why should I bother? – jippie Jul 30 '12 at 19:19
• @jippie: If that's someone's attitude, I'd rather not have them here. There are all kinds of free imaging tools for just about every platform. If people want to post here, they have to learn that dumping unnecessarily large images on us is just as unacceptable, and will be met with the same scorn, as using text-speak. This is truly not a hard thing to ask people to do, but if they can't or won't for whatever reason, then they don't get to post here. No loss on our end. – Olin Lathrop Jul 30 '12 at 20:00
• @OlinLathrop - I think the important words in your comment are "they have to learn". If we do it for them, they won't learn. I think EE/SE needs a feedback mechanism to teach the better way, and maybe that means setting up a handful of meta questions or blog posts to refer to on resizing images. If someone really can't manage, some of the more experienced ones can still jump in. – jippie Jul 30 '12 at 20:04
• Here's another one just posted (6.37MP) – Oli Glaser Jul 31 '12 at 14:35
• @Oli - Great. Thanks Oli, you really know how to make my day! ;-) – stevenvh Jul 31 '12 at 14:37

Yes, a irresponsibly large image is only one of several things someone can do to make their post annoying. But it's different in that this is accessible to anyone regardless of having to pay money for tools or how proficient they are with English. In short, there's no excuse.

Some say it's OK because the system resizes it for you, but this logic has two flaws:

First, that's not always true. On one of the systems I'm frequently on large images are not resized. Here is a snippet of the screen shot of the top of this question:

The fuzzy gray area is the top left corner of the full size original image. I can't even see the connector part in that picture with the window I am using without scrolling.

Second, most browsers don't shrink pictures very well. When they do shrink them, it's usually just resampling at the output resolution. That is fine when the original is fuzzy enough as in this case, but it makes a mess of line art like schematics. The basic issue is resize algorithms generally don't do anti-aliasing, probably to allow for faster display since good anti-aliasing takes significant compute cycles.

The right answer of course is for users to do the work once to properly size a picture, then upload that. Then every browser can display it properly without having to guess what it should do with it.

Part of the documentation for the site should clearly state that:

1. Pictures should be sized to convey the necessary information but not more. We suggest limiting the largest dimension to around 600-640 pixels. That should be sufficient for most pictures. There are cases where you might need more, like a scan of a paper schematic from a manual for example. We leave this to you to decide, but please think about it carefully and only upload a larger image when the extra detail is really needed.

2. Take the extra time and crop the image. The one in the question is a great example. Simply cropping it to contain only the object of interest reduced it to 1961 x 746 pixels, which is 3.4 times less without any loss of information or resolution. Here is the result of proper cropping scaled to a maximum dimension of 300 pixels:

3. Focus the camera! Blurry pictures are annoying to look at and don't contain much information. This one is a great example since it's so poorly focused we really can't tell what it's trying to show. And no, my phone won't focus closer is no exuse. First, it probably does. Second, even most cheap point and shoot cameras have a macro mode. If your camera or phone can't do the job, find one that does. Posting a blurry mess is no solution to anything.

4. Try to do a little black and white level correcting if you can. This is a bit like English not be a native language for some. We don't expect everyone to get this right. Washed out blacks, dingy whites, and a yellow cast will be forgiven to some extent, but at least think about it. There are free tools out there to do these things, so this is accessible to everyone. So while we won't require it, and some failure here will be forgiven, presenting something a cleanly as possible exhibiting attention to detail is a good idea and shows respect for those whom you are asking for free help. This may help you get better and more answers.

Let's at least say all this to users clearly like we do other rules and recommendations for this site. That also gives us something to point to when resizing and cropping a picture for someone, and provides a more clear justification for a downvote. I have downvoted questions before that were poorly communicated, in part based on sloppy and annoying pictures.

A bad picture is more of a insult to us all than bad wording, because anyone can fix the basics of a bad picture whereas it takes time and effort to learn english. We need to draw a line and stick to it, else we'll get more of the same dismal quality of pictures we have seen here lately.

• +1 - the point about cropping to get rid of redundant information is a good one. I'm no expert photographer, but I'm aware that e.g. Microsoft Picture Editor can crop and has a convenient "size for web" option that takes seconds to use. Also IrfanView is a good free image viewer/editor that will do all this and more. For the macro stuff with simple camera, when using a mobile phone camera in the past I have done close PCB pictures through a x10 loupe (and macro mode), works very well indeed. – Oli Glaser Jul 30 '12 at 19:33
• Olin, I am very curious to know what machine, OS and browser you usually use when on the EE SE. – Rocketmagnet Sep 13 '12 at 9:59

I don't see a huge difference between oversized images and a lot of other "poor etiquette" behaviors, such as:

• Atrocious spelling and grammar that practically make the question unreadable
• Failing to mention parts or link to datasheets/relevant pages.
• Failing to use formatting to enhance the readability of their post.
• Not using MathJax to make pretty equations.
• Using MathJax excessively for units in a post.

We should nicely encourage the user to crop and resize to make the image more web friendly. However, just like English isn't everyone's first language, not everyone is proficient with computers to the point where they could make their own crops and resizes. Would you consider a filter that looks for the = character and blocks the question if it doesn't use MathJax? Would you approve of a filter that demands a rewrite if a post doesn't pass a spelling or grammar check? We are constantly asking users to include an image for clarification, we shouldn't throw up another barrier for that to happen.

It isn't the end of the world if we the community need to do the finer image editing to optimize the question for the web. I'd be willing to bet that imgur would charge more for the bandwidth of the large image than the storage, especially for popular questions/answers.

• There is one huge difference. English takes time and effort to learn, but image cropping and resizing tools are accessible to anyone. Bad English may be the limit of someone's ability (not that it makes it less annoying of course), but there really is no excuse for dumping a picture on us like the one referenced in the question. – Olin Lathrop Jul 30 '12 at 14:41
• @OlinLathrop What I'm concerned about is jumping down newcomer's throats because they didn't follow proper etiquette. I would say fix it for them the first time, leave a friendly message about cropping and resizing with a link to a simple guide for cropping and resizing. There is an excuse - it's the first time they uploaded big pictures. After that, maybe take some corrective actions (explained clearly). – W5VO Jul 31 '12 at 16:21
• That makes no sense. Just because it's the first time they posted a ridiculously large picture here it's somehow OK? You don't need special knowledge of the site or electronics to understand the simple courtesy of presenting whatever it is you're saying neatly, understandably, without a minimum of extraneous clutter. Dumping a 5 Mpix poorly focused picture of mostly background with a small item in the middle is just plain rude, whether it's done here, as a presentation to your boss, for homework, or anywhere else. – Olin Lathrop Jul 31 '12 at 16:34
• @OlinLathrop It is very reasonable that they might think the more data they give you the better. It is not noticeable on my computer/bandwidth to have a super high res image shown. Regardless of everything else, being nice to new users when they are first learning the rules is a must on this site. There is no discussion point where you will convince me otherwise there. – Kortuk Aug 4 '12 at 13:43

Closing a question sounds final and comes to me as not particularly hospitable to new users. Maybe a better option is to "Question suspended until image resized to reasonble geometry." With a subscript "Please mind our mobile users.". Then uploading a smaller image can automatically resume the question.

Sure it needs mod attention, but it solves the problem that some images are rightly large scale whereas others aren't.

Also I think many users don't realize the size of the actual image, so an (annoying?) warning during upload of a large file could work.

• Or a warning box for every 100kB of upload (of course with varying texts so it is obvious that it is different windows you're clicking, resulting in 50 warnings when your upload is 5MB in size ;o) – jippie Jul 30 '12 at 19:46
• + 1 - yes that's also my suggestion (see comments), as I think it's probably not due to (most) folk not caring, more the fact that most are unaware. A simple warning and request to resize/crop if possible would probably result in most people doing so. If the problem persists then more "drastic" measures could be discussed. – Oli Glaser Jul 30 '12 at 20:02
• How about a warning if you try to upload a image with a maximum dimension exceeding 620 pixels. It won't prevent you from doing so, but points you to the documentation on this issue and removes that excuse that you didn't know by forcing you to click on something like Yes, this image really needs to be high resolution and is already cropped to show only the relevant part. – Olin Lathrop Jul 30 '12 at 20:04
• @Olin - yes, that's the kind of thing I'm thinking of, I reckon it would work quite well for most. – Oli Glaser Jul 30 '12 at 21:12

Why not suggest a site feature that automatically takes a lower resolution "thumbnail" of the image and places that in the question with a high rez version that can be accessed by clicking. This can probably be done by the software relatively easily and automate the process.

This seems the cleanest way, users dont have to worry about downsizing and uploading two different versions and olins computer can load the image.

• I would like it at my discretion as the author of a post how big the in-line image is. Sometimes but not often you need higher res, and then the thumbnail can be a hassle. I'd hate to see the system wrecked because a few lazy people abuse it. Let's deal with the real cause, which is the lazy people and their sloppy attitude. I wouldn't mind having to click something that says yes I'm sure I need this and its already properly cropped in the few cases where it might be necessary. – Olin Lathrop Aug 4 '12 at 18:56
• @OlinLathrop why not make that part of the tool? This just makes it so the inline image matches your resolution and you can click for full rez. The having to verify you want that high of image could bypass this, otherwise it makes a thumbnail? – Kortuk Aug 4 '12 at 19:23