Imagemagick commands that trims transparent pixels from an image.

imagemagick-trim-transparent.sh

# Trim a single "input.png" image and save to "output.png"
magick input.png -trim +repage output.png

# Trim a single "image.png" image and overwrite the original file (based on @enijar comment)
mogrify -trim +repage image.png

# Trim and overwrite all png images from the working directory (based on @enijar comment)
mogrify -trim +repage *.png

Thanks!

Here's how to loop that over all images in a folder in case anyone stumbles upon it:

for f in *.png; do convert $f -trim +repage $f; done

You can do this much simpler with:

mogrify *.png -trim +repage

@enijar I had to put .png at the end to get it to work (on a Mac). Imagemagick is sensitive to order of params.

mogrify -trim +repage *.png

Pretty leet, especially mogrify 👍