Image Booth: Manipulate images split in layers

This class can be used to manipulate images split in layers.

It can create images that are composed of several independent layers.

The class can apply different effects separately to the images in the different layers or to all layers at once like resizing the canvas.

Separate classes are available which implement different types of operations like Gaussian blur, threshold, grayscale, line detection, gradient detection, laplacian filter, Sobel filter, color replacement, brightness/contrast, photonegative and rotation (and not GD's terrible rotate) with plenty more coming.

In the end it can merge the image layers in a single image that is saved to a file or served as the current script output in any format supported by the GD extension.