Using Mr. Thumb like I advised a simple script to get it working would be
<?php
include './mrthumb.class.php';
// The image you are resizing. Can be a local path as well.
$image = $_GET['i'];
$quality = 100; // percent
// In this example we are resizing the image in proportionate sizes.
// Below we are specifying the MAX width and height.
$width = 100; // Pixels
$height = 130; // Pixels
// Start Mr. Thumb v1.0
$mrthumb = new MrThumb();
// Render the image
$mrthumb->render( $image );
// Resize the image proportionately
// $mrthumb->constrain( $width, $height );
$mrthumb->proportion( $width, $height );
// Finally, output the image to the browser!
// Optionally we can save the image to a destination
// $mrthumb->saveto( $destination, $filename, $quality );
$mrthumb->output( $quality );
// Clean up after you are done! ;)
$mrthumb->clear_cache();
?>
Then save that to your web server along with the mrthumb class and call a thumbnail in your webpage like
<img src="./mrthumb.php?i=images/myimage.jpg" alt="My Image" />