Thumbnailing
It's been said by many a carpenter: "The only nail you don't want to hit with a hammer is your Thumb nail". But that's not what we mean here by thumbnail. In Category:Graphics, a thumbnail image is a smaller version of the original (perhaps as small as your thumb nail) that gives you an idea of the content of the graphic, obviously with less detail. MediaWiki software creates automatic thumbnails of images that are uploaded into the system. Don't worry, it only creates the thumbnail on demand, so that it doesn't do more work than necessary.
Contents
Image Hacks
Assorted Sizes On Demand
Because you can specify any size for your thumbnail, you can use your wiki to produce various sizes of media for use in different ways (think newsletters, email campaigns, logo galleries, media kits). Granted, your designer is going to want to ensure the results are good enough for public use and distribution, but for many cases the results can be quite acceptable.
| https://freephile.org/wiki/File:Eqt.logo.png | Article Page |
| https://freephile.org/w/images/8/8c/Eqt.logo.png | Hashed directory storage |
| https://freephile.org/w/images/thumb/8/8c/Eqt.logo.png/120px-Eqt.logo.png | Thumb example |
| https://freephile.org/w/images/thumb/8/8c/Eqt.logo.png/128px-Eqt.logo.png | Non-existant thumbnail that will be created if URL is accessed. |
| https://freephile.org/w/images/thumb/8/8c/Eqt.logo.png/ | All thumbs |
The logo file at https://freephile.org/wiki/File:Eqt.logo.png is 599 � 378 pixels and is stored at
https://freephile.org/w/images/8/8c/Eqt.logo.png
Meanwhile, the thumbnails are served from
https://freephile.org/w/images/thumb/8/8c/Eqt.logo.png/120px-Eqt.logo.png
When you request an image with different dimensions, that file is saved in the 'thumb' directory of the image. Unless those images are deleted by an administrator, you can then use them as web-accessible sources in your other content. See https://freephile.org/w/images/thumb/8/8c/Eqt.logo.png/ for a list of current logo files in various sizes. The truth is, you don't even have to edit a wiki page to create the thumbnail on demand. Simply requesting the file will create it. E.g.
https://freephile.org/w/images/thumb/8/8c/Eqt.logo.png/128px-Eqt.logo.png
| Wiki Text | Result |
|---|---|
| [[File:Eqt.logo.png|1000px|link=]] |  |
| [[File:Eqt.logo.png|200px|link=]] |  |
| [[File:Eqt.logo.png|128px|link=]] |  |
| [[File:Eqt.logo.png|64px|link=]] |  |
| [[File:Eqt.logo.png|16px|link=]] |  |
| Wiki Text | Result |
|---|---|
| [[File:QB_cube.svg|1000px|link=]] |  |
| [[File:QB_cube.svg|200px|link=]] |  |
| [[File:QB_cube.svg|128px|link=]] |  |
| [[File:QB_cube.svg|64px|link=]] |  |
| [[File:QB_cube.svg|16px|link=]] |  |
Note that svg upscaling doesn't seem to be working
Old Versions
Because the wiki versions files, you can update any media file, and still have the "old" one accessible. This works in much the same way as the thumbnailing too... except the word 'archive' is in the path.
compared to
Thumbnailing Errors
If you get an error about "Error creating thumbnail: Unable to save thumbnail to destination", and you've checked that the "images" directory is writable by the web server, as well as any sub-directories, then you might be able to solve the problem by unsetting the $wgTmpDirectory setting in your LocalSettings.php file. I had
$wgTmpDirectory = "{$wgUploadDirectory}/tmp"; in a v1_26 version of MediaWiki. Thumbnails were generated after I commented-out the setting (thus restoring the default from DefaultSettings.php -- which luckily worked for me).