Tutsplus image resize class: bug with large images?

Has anyone tried resizing large image files with using the image resize class from tutsplus?

link: http://net.tutsplus.com/tutorials/php/image-resizing-made-easy-with-php/

When trying this script with files larger than 3 mbytes nothing happens. The script works fine with files <= 3 mbytes

Thank you

Problem solved.

The script stopped to run because of the memory size limit defined in php.ini.

32M is not enough for pictures larger than 3000px width.