Abstract: The VC-1 is a parallel graphics machine for polygon rendering based on image composition. This paper describes the architecture of the VC-1 along with a parallel polygon rendering algorithm for it. The structure of the VC-1 is a loosely-coupled array of 16 general-purpose processors, each of which is equipped with a local frame buffer. The contents of the local frame buffers are merged in real time for generating the final image. The local frame buffers are virtualized with a demand-paging technique, by which the image memory capacity for each local frame buffer is reduced to one eighth of full-screen capacity. Polygons are rendered in either pixel parallel or polygon parallel depending on the on-screen area of each polygon. The real performance of the VC-1 as well as estimated performance for systems with up to 256 processors is shown.