The constraints of drawing with an antiquated plotter include the difficulty of drawing anything but straight lines. So to represent photographic images took some creativity. This software draws random lines in a density inversely proportionate to the light density of each area in the photograph.
The result is something which the plotter can draw in an hour or so for an 8 x 10 inch image. The image is stochastic in the sense that each instantiation of a given input photograph will produce a technically distinct image -- the lines are placed by probabilities rather than a determinate relationship to input.