One line of code

For an example of when programming can be a pain in the ass. I spent about three hours today coming up with this one line of code:

convert -resize 310x155 -size 310x155 +swap -gravity center -composite start.jpg background.gif finish.jpg

That line will automatically resize an image to fit inside a 310 pixel wide by 155 pixel high image area with a background image as padding.

It's simple now that I have it, but it was hard to find documentation and examples to get to the end result.

As an example, here's a starting image:

Initial photo of two golfers shaking hands

And after the conversion with a simple black background:

Two golfers shaking hands after a round