Question

I’d like to use “convert” (or whatever) from Imagemagick to combine two different sized images. I’d like them to be aligned at the bottom left corners. For example, I have two images:

trans_alpha.png (a transparent 42×37 blank image)
and shadow.png (a 68×23 image, which I want overlaid on trans_alpha.png aligned at the bottom left)

The result I’d like would be a 68×37 image, NOTE these sizes are examples only, I don’t want to put the size into the command line, I just want to use the sizes from the input images.

I have tried a lot of combinations without success:

Attempt no. 776 (close, but aligned to top left, not bottom left)..:

convert trans_alpha.png -background none shadow.png -gravity SouthWest -layers merge  +repage result.png

Attempt no. 841 (aligned correctly, but result image isn’t wide enough)…

convert trans_alpha.png shadow.png -gravity SouthWest -composite result.png

Hopefully that makes sense.
Thanks,

Paul

Answer 1

In answer to my own question (courtesy of the clever people on http://www.imagemagick.org)

convert \
  trans_alpha.png shadow.png \
 -flip \
 -background none \
 -mosaic \
 -flip \
  result.png