Use PHP:
<?php
function rotateImage(){
// The file you are rotating
$image = 'http://assets.espn.go.com/i/ncaa/07mens_bracket.gif';
//How many degrees you wish to rotate
$degrees = -90;
// This sets the image type to .jpg but can be changed to png or gif
header('Content-type: image/gif') ;
// Create the canvas
$source = imagecreatefromgif($image) ;
// Rotates the image
$rotate = imagerotate($source, $degrees, 0) ;
// This shows the the image
imagegif($rotate);
//or
// This saves the image
//imagegif($rotate, 'NCAABracket.gif');
}
echo rotateImage();
?>
If you are rotating a JPG or PNG just change all the gif accordingly.