I'm on a shared server with IM version 6.2.6. I'm trying to compose two images together using the command line.
This command (composite image.jpg shirt.jpg result.jpg) seems to reproduce image.jpg and shirt.jpg and call them result-0.jpg and result-1.jpg.
I tried using the convert command. This command (convert shirt.jpg image.jpg -composite result.jpg) produces result.jpg that looks like shirt.jpg with a black square the size of image.jpg on top of it. Something like this ...

I really have no idea what to try next. Any suggestions for me?