This documention is outdated, it refers to an version older then 18 months. Please ask the maintainer of this package to update this documentation.
This module is EXPERIMENTAL. That means that the behaviour of these functions, these function names, in concreto ANYTHING documented here can change in a future release of this package WITHOUT NOTICE. Be warned, and use this module at your own risk.
ImageMagick is a robust collection of tools and libraries to read, write, and manipulate an image in many image formats (over 68 major formats) including popular formats like TIFF, JPEG, PNG, PDF, PhotoCD, and GIF. With ImageMagick you can create images dynamically, making it suitable for Web applications. You can also resize, rotate, sharpen, color reduce, or add special effects to an image and save your completed work in the same or differing image format.
Note: The above text is from the ImageMagick Website (http://www.imagemagick.org/), therefore not everything does apply to this extension at the moment, but it will some time in the future. Hopefully. And the link above is also a great source, if you don't understand everything here.
imagick went through a major upgrade with version 0.9 and is not backwards compatible to older versions. You should look at the examples, which come with the package, for some documentation about the new API.
Read the INSTALL file, which comes with the package. Or just use the PEAR installer with "pear install imagick".