I'm using ImageMagick's composite command to compose one smaller image over larger one. The resulting image should be of size of the background image (the larger one). Additionally I want the smaller one to be always of the same size.
Currently I have such a simple invocation:
composite -gravity SouthWest watermark.png photo.jpg photo.jpg
The problem is that I get different sizes of watermark for different photos and I don't know how to set it to be fixed size. I tried -resize, -geometry and -size options but all of them change size of resulting image and not the watermark.