Change to how thumbnails are generated

Posted under General

I am thinking of switching to cropped thumbnails, the way Pixiv/Flickr handle it. I feel that it gets rid a lot of empty space on the listing page and it makes a big difference when viewing the site on a phone. You can see how it might affect Danbooru by visiting http://testbooru.donmai.us.

If I went ahead with this change I would regenerate all past thumbnails to use the new style.

Updated by lvk

I'm not entirely opposed to this but I would like to know if the number of users connecting to the site on a mobile browser is actually significant enough to warrant such a change. I know that the combined total of visitors who have accessed 3dbooru on a mobile browser this year is less than 6k out of over 150k but I'm curious how high that number is over here.

Just to make sure I understand the change...

Before: Images are scaled down until the longer dimension fits inside the square thumbnail, meaning there's never a need for cropping, but white space is added to the sides for tall images and above/below for wide images.

Now: Images are scaled down until the shorter dimension fits inside the square thumbnail, meaning for wide images, the sides are cropped, and for tall images, the top and/or bottom is cropped.

I can't help feel concerned. I like knowing that I can see everything in the image from the thumbnail, even if I have to squint a bit. I can't think how many times my attention has been drawn to an image because of a detail near the edge of its thumbnail.

I agree that it is annoying that very tall/long images and comics with many panels have thumbnails that say nothing about the image. However, it's also nice that the thumbnail tells me that an image that won't fit on my screen at a sensible scale. Again, coming back to liking that scaled thumbnails show me a small/far-away version of the entire image, not just a sample like cropped thumbnails do.


imho, it would be a nice feature to give thumbnails a uniform preview image. this would be especially useful to larger (taller/wider) images like long comics where the subject image is greatly obscured by significant difference in dimensions. however, i'm curious of what will be its effect on lowres images?

This change will break iqdb, or I'll have to change it to retrieve the full image for indexing, which will be annoying.

Quite honestly I prefer the way it's done currently.

Or maybe you could scale thumbnails so that the short dimension is 150 (instead of the long one as it is now, or maybe the long dimenstion to 300 like moe and konachan do it), and then use CSS to crop them. That way there could be a user setting to change between cropping or downscaling them. The disadvantage would be that the files get larger, of course.

But this way, iqdb et.al. could still work with the thumbnail because it contains the full image information

Would it be possible to implement a user setting to change between the two, or is this a little more fundamental? It would be nice if users could set a limit. i.e. "crop if taller than 3:4 or wider than 16:9".

Edit: You could make a mobile version of the site. I don't know how much work that would be, though.

Make it a toggleable option?

I know this will completely break anything 4koma or incredibly_absurdres, and can make some images seem safe when in reality they are not (because the thumbnail won't contain the explicit parts).

The non-cropped thumbnails also tell me instantly what the aspect ratio of the image is like.


i frequently browse from my phone as well, and i too, would prefer to know whether i'm looking at a comic/very long image or not right off the bat.

if you want to set a cropped system, i'd at least request to have the size of the image shown below the image.

I stick score and favcount below all my thumbnails and am comfortable with how things are spaced out, so I want to keep things the way they are. Piespy's toggleable, CSS approach sounds more reasonable.

If you're into changing how thumbnails are generated, how about trac #1109 instead? :p

I gave it a whirl on a few of my devices and I actually have to say that I prefer it as it is now. Not only does it negatively apply on my two tested devices, but it also negatively applies on my desktop.

My monitor is 46", so I realize my desktop is an exception, but not knowing what I'm really opening is a huge, major problem to me. Not just from the dimension, but from the content. And I don't just mean the explicitness of it.

At least make the new format optional, if you have to go with a change.

Thumb pages look better

You can't see the complete image
Imagesearch needs full image -> way more traffic

I don't like this...

Concerning mobile users, what about a layout setting defining how many rows and columns are displayed? I'm sure people with very large displays would like to adjust that as well.

I am mostly indifferent to which is used, but would love if you could click on the entire "box" rather than only the visible pixels.
For extremely tall images you only have a thumbnail some 3 pixels wide to click on, so I kinda feel like I'm playing a sniper game...

piespy said:
Or maybe you could scale thumbnails so that the short dimension is 150 (instead of the long one as it is now, or maybe the long dimenstion to 300 like moe and konachan do it), and then use CSS to crop them. That way there could be a user setting to change between cropping or downscaling them. The disadvantage would be that the files get larger, of course.

I like this idea and is probably what I'll end up doing.

I'm wondering if you were ever able to implement that anime face detection algorithm I linked you to way back when we were collecting Danbooru 2 blue sky feature ideas. If you have, I think this would be an excellent place to use it, so the cropped (re-sized) thumbnail could center on a face if appropriate (by modifying the CSS to display a square at the right height or width along an image).

I think potentially cropping something such that you'd get the only the torso or belly would be sort of annoying. This would happen for a centered square thumbnail on a narrow image like post #477535*.

Overall, I do very much like the full square thumbnail aesthetic though.

EDIT: *Actually You'd just get her pelvis which is really not supposed to be the focus or representative of the image. See http://i.imgur.com/FDSrv.jpg

EDIT EDIT: Actually I see you are using the top or left to generate the square, which works surprisingly well for most images. It would fail on post #513951 or post #237776 though, where a defined focus point would remedy this. (You'd get http://i.imgur.com/tOXNX.jpg and http://i.imgur.com/BV1TK.jpg respectively).


Personally, I'd rather not see cropped images unless there's a way to "tag/mark" the focus of the image to be the center of the thumbnail, ala FaceBook profile images. And that sounds like far too much trouble for the return.

It seems like many large images under white_background would have a nonsensical thumbnail.

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