The PN program was designed to distinguish and measure differences between two pictures. Primarily intended to help in the Alzheimer project, analyzing anatomical features of the brain, the program can very well be used to analyze other types of pictures.
Through a series of buttons and menus, analyzing tools that come from statistical physics are incorporated in a GUI program. The focus is on uniting arcane and command-driven algorithms into a user-friendly environment.
The user interface of the PN program is writen in Tcl/Tk using the BLT and Togl extensions. The Tcl/Tk language is a scripting language that permits rapid prototyping of GUI programs while providing an uniform interface across different platforms. The BLT extension provides x-y graphying capabilities that aid in the analysis of data. The Togl "extension" provides high level graphics API, using the OpenGL API, for the visualization part of the analysis. The computational engine of the PN program is writen in C++.
Here is a screen capture of the program: