It seems you also asked this at the Wikipedia Help Desk (which, in my opinion, is really a better resource for Wikipedia questions).
The answer you got, which seems to suit your needs, was:
Over at dumps.wikimedia.org is a link to a compressed "all-titles.gz" file containing the names of all pages at Commons. That would take an hour or two to download at ...
Here is the URL pattern:
<width> and <height> seem to have no effect.
Example around the White House:
As of September 2015, Wikimedia Commons hosts about 62.5 TB of media files (not counting old revisions).
On Wikimedia Commons, there is a special page that provides a breakdown of the total size of Wikimedia Commons by the file-type. Adding them up will give you the total size of Wikimedia Commons. There is also an SQL query that can give you the total size ...
From File:A to https://commons.wikimedia.org/wiki/Special:Redirect/file/A
https://commons.wikimedia.org/wiki/Special:Redirect/file/11-cube_t0_B5.svg redirects to https://upload.wikimedia.org/wikipedia/commons/a/aa/11-cube_t0_B5.svg
As far as I know, MediaWiki's standard installation does its search on the page syntax. So you may simply combine your key word with the category definition in parantheses:
You can sort by size in catscan (by Magnus Manske, the creator of MediaWiki): http://tools.wmflabs.org/catscan2/catscan2.php
Berlin images sorted by size; or, more useful category, Quality images of Berlin sorted by size. You can't filter by width, but file size is a good approximation, there's a width column and you can pick the appropriate category. ...
If you use the search query File: intitle:svg, you will get all files that have "svg" in their name. This will include files that do not have the .svg extension, but have svg in their name, but those should be rare.
If you are looking for an answer specifically for de.wikipedia.org then go to the Gadgets section of the preferences and activate the Gadget with the description "Überspringen der lokalen Dateibeschreibungsseite, um sofort nach Commons zu kommen." Note that this currently only works if you have Media Viewer disabled.
To make this work on any wiki, or with ...
Note: in this answer, I'm primarily talking about the English Wikipedia, because that's the one I'm most familiar with. This answer may not apply to other Wikimedia Foundation projects, and especially not to Wikimedia Commons, which is it's own minefield of copyright- and licensing issues.
This answer comes in three parts: legal, technical, and policy.