Abstract: A diffetence engine is described that is designed to be used as low level component of a raster graphics architecture. The speed of the system (11 ns per operation) is achieved by the use of custom VLSI components for the most primitive operations. This permits the video rate reconstruction of images and other signals compressed by encoding them on various polynomial bases. The paper describes a feasibility study for its use for image reconstruction. The study shows that the system can be applied to the decompression of spline wavelet encoded images.