There are 2 posts in the Images category:
Resize an Image on the Fly with PHP
Easy PHP functions that let you resize images automatically using PHP. One keeps the same aspect ratio by cropping. Another function allows you to set a max width or height and shrink to fit. Or you can force to specific dimensions. » View Post
Simple PHP Image Upload Form
This little chunk of PHP allows a user to upload a JPEG image and then resizes that image to generate a thumbnail automatically. With a little work, you can change the file types allowed, formula for resizing the thumbnails, etc. but I wanted to keep this simple so only JPEGs are allowed and everything is resized based on height. » View Post