ASP/JavaScript pixel selection

Looking for a script written in ASP/JavaScript allowing the ability to "block" or reserve regions on an image. The script should display a grid, allow the ability to select a series of pixels (in an interactive drag to select manner) and prevent pixels from being selected which have already been blocked. Once blocked the coordinates need to be added to a database and I can handle the rest from there. The concept is very similar to: * [login to view URL] * [login to view URL] NOTE: I do not need the entire application re-written, just need the pixel selection tool created.