Need a tool to set multiple image backgrounds to transparent

Question

I'm searching for a software/tool to set the image background (black) to transparent.

I want to to remove all the black and make the image transparent.

All the images are .PNG and I have around 191 hence why I need a tool to do multiple images otherwise it could take me a very long time.

Answer 1

Use either graphicsmagick or imagemagick mogrify tool with the -transparent black option. When I ran it on your single sample image it looked like this:

gm mogrify -transparent black 'sprite sheet 4.png' 

To do a few hundred of these, you'd use it like this:

for f in *.png ; do gm mogrify -transparent black "$f" ; done

Be sure to work on copies of the files -- mogrify modifies files "in place".