To install and use the Image Markup Tool, all you need is Windows (we recommend Windows 2000, XP or VISTA). (You can also run the program under WINE on Linux, and you may be able to get it working through Darwine on OSX. See WINE for more details.)
If you want to compile the application yourself, you'll need to read the following instructions.
The Image Markup Tool is coded with Borland Delphi 2005 Professional.. The source code files for this project are listed with descriptions and download links on the Source page. This is a list of the other libraries and packages that you will need to install in order to build the project yourself. Each package is best described by its own Web site, so I have omitted any explanations here. For open-source projects, I tend to keep my installations relatively up to date, although I may not update a particular library until a convenient time unless there is good reason (such as a bug-fix I need) to do so. If you compile the project with the latest versions of these libraries and encounter problems, let me know.