Another of those posts that are largely for my own benefit.

I’ve been spending a lot of time in various image editing programs recently (largely GIMP, but with a bit of Inkscape on the side). Yesterday it transpired that a folder of 24x24 images needed to be made slightly smaller as a matter of some urgency. I had a feeling ImageMagick would probably do the job (it usually does), but I couldn’t remember how.

It’s actually fairly straightforward. Navigate to the directory containing the images (via the terminal) and then enter the following command:

mogrify -resize 20x20 *.png

Which will resize all PNG files to 20x20 pixels.

This can obviously be altered to cater for different sizes and file types. So yes, ImageMagick saved the day again and I actually managed to leave work on time.