ETOOBUSY 🚀 minimal blogging for the impatient
Crop an image with ImageMagick
Using ImageMagick to crop one or more images from the command line.
Do you know ImageMagick? It’s an amazing set of command-line tools for doing image manipulation. It allows doing a lot - I mean really a lot - of things, although not always simple things are simple.
Anyway, this time I needed to do some cropping.
Usually when I do this with a GUI I set one corner, draw a rectangle up to the diagonally opposite corner, and there goes the cropping. It turns out that the input required by ImageMagick is somehow different:
- size (width and height) of the rectangle to cut, and
- offset (x and y) of the upper-left corner (assuming that y increases downwards).
Hence, a couple of points
(5, 7) and
(27, 33) become
After the first half time… it becomes shell script time! So here we go:
I hope the comments make sense.
The list of files to crop is provided in the standard input, so that
this can be piped in the shell. There are two positional arguments: two
points (in the
x,y form, like e.g.
19,72) and an optional
substitution suitable for
sed, to generate the name of the cropped
The names of cropped files are printed on standard output, for further processing down the line.
The cropped images are produced with
means that there is no virtual canvas preserved and it just works.
Well, I guess it’s all for today… I hope you will enjoy!