Generate Thumbnail gif's

Dear all, Is there any pre-written code available on the net to generate thumbnail images for a picture. I mean I send the path of the image and my PHP Script should be able to generate a gif file of size 100x71 or something like that. Thanks & Regards, ___________________________ PHPLover * : PHPLover@Hotmail.com "Göd döësn't pläy dícë." - Älbërt Ëínstëín ************************************************************************** This email (including any attachments) is intended for the sole use of the intended recipient/s and may contain material that is CONFIDENTIAL AND PRIVATE COMPANY INFORMATION. Any review or reliance by others or copying or distribution or forwarding of any or all of the contents in this message is STRICTLY PROHIBITED. If you are not the intended recipient, please contact the sender by email and delete all copies; your cooperation in this regard is appreciated. **************************************************************************