displays the color frequencies of an image as a cloud of colored cubes in 3d space use 'I' to toggle the display of the image in the background. Other documentation and explanation is available in the main .pde file
Warning: This program does a lot of hard things and may take long to start (and have low fps) if your computer is flow. You can tweak a variety of constant settings in the code to make it run smoother if you want.