PHP GD trim/crop whitespace around image

I have many images that have a white background. Too many to use the "trim" function in photoshop, so I would like one written using GD in PHP. Start at the top of the image and delete every row going downward until you hit the first row that isnt 100% white pixels all the way across. Then start at the left of the image and delete every column going across until you hit a column that isnt 100% white pixels all the way down. Then start at the right of the image and delete every column going accross until you hit a column that isnt 100% white pixels all the way down. Then start at the bottom of the image and delete every row going upward until you hit a row that isnt 100% white pixels all the way accross. The end result is an image where the topmost row of pixels is not 100% white, and the same with the left, right, and bottom. ## Deliverables 1) Complete and fully-functional working program(s) in executable form as well as complete source code of all work done. 2) Deliverables must be in ready-to-run condition, as follows (depending on the nature of the deliverables): a) For web sites or other server-side deliverables intended to only ever exist in one place in the Buyer's environment--Deliverables must be installed by the Seller in ready-to-run condition in the Buyer's environment. b) For all others including desktop software or software the buyer intends to distribute: A software installation package that will install the software in ready-to-run condition on the platform(s) specified in this bid request. 3) All deliverables will be considered "work made for hire" under U.S. Copyright law. Buyer will receive exclusive and complete copyrights to all work purchased. (No GPL, GNU, 3rd party components, etc. unless all copyright ramifications are explained AND AGREED TO by the buyer on the site per the coder's Seller Legal Agreement). ## Platform PHP Version 5.1.2 GD Support enabled GD Version bundled (2.0.28 compatible) FreeType Support enabled FreeType Linkage with freetype FreeType Version 2.1.7 GIF Read Support enabled GIF Create Support enabled JPG Support enabled PNG Support enabled WBMP Support enabled XBM Support enabled