PHPImageWorkshop is an open source class using the GD library that helps you to manage images with PHP. This class is thought like photo editing software like Photoshop and GIMP: you can superpose many layers or even layer groups, each layer having a background image.

The class was thought to be the most flexible possible: superimposing an infinity of images (to add watermark), rotating (and not just 45 / 90°), resizing, cropping (thumbnail). An ImageWorkshop object is a layer AND a group at the same time. It has got a background image and a stack of sublayers on the top of its background.

Requirements: PHP Framework
Demo: http://phpimageworkshop.com/
License: GPL License