Thumb, crop or resize on images not working – locally as well as on the server

Oh, it’s not? In the phpinfo file is nothing written about imagemagick except in that table I made the screenshot of.

How do I check for Imagemagick exactly?
Where do I type this?

convert -v

Your server might not be able to handle huge images with its current settings.

That could be! There are images like 3000x4000 px or 1200x900 px – not absurd huge images… I mean, that should not really be a problem, right?

Either way: I would change it like proposed here:

In the php ini file?