Does anyone know how to make a image have rounded corners using a PHP script?
There are a lot of options available, you can find them using Google. The easiest way though is using the Thumbnailer. It's as simple as two lines of code:
// make an object
$th=new Thumbnailer("your-photo.jpg");
// create a 120x90 thumb and round its corners
$th->thumbFixed(120,90)->round()->save("your-thumb.jpg");
Fun it is, isn't it? :) There are a lot of other options available. The corners will be antialiased.