Abstract: Fractal functions are explored as a representation for rough data in computer graphics. Two new techniques for using fractal interpolation functions to approximate rough functions and curves are introduced. The first is based on a Hough transform of fractal function transformation parameters. The second is based on previous techniques in fractal image compression. These techniques are then demonstrated on the task of recovering the parameters of a fractal function, approximating a rough function and approximating the boundary of a leaf.