Legacy ImageMagick Discussions Archive

I'm trying to resize a picture and put it on top of a black background using this command
Let's say somePic.jpg does not fit the ratio of 300x100, I would expect it to be centered within the slot allocated to it, but with the this command its left aligned.
I've had luck doing this with this style command:
Thanks

try

convert somePic.jpg -resize 144x82 -background black -gravity center -extent 144x82 newpic.jpg

see
http://www.imagemagick.org/Usage/crop/#extent

There are two composition positioning methods in IM

• geometry offsets with gravity placement typically two images only
• layering of multiple images with canvas size, and page offsets (relative to a origin)

which method is used by what composition operator depends on that operator. Only one operator understands both and that is -layer composite, which uses geometry/gravity one for global placement, and layer/page for individual placement relative to global placement.

See IM examples, Compositing Images, Positioning The Overlay Image
http://www.imagemagick.org/Usage/compose/#geometry

The section immediatally above lists the composition operators and what positioning methods they use (if any)