A real-time video signal processor suitable for motion picture coding applications

A real-time video signal processor (VSP) system has been developed. The system employs three multiprocessor clusters, each of which has 12 video signal processor modules (VSPMs). A VSPM in a cluster processes its assigned subimage by using an overlap-save technique. Each cluster uses the same multiprocessor structure, in which homogeneous processor modules are connected to input, output, and feedback buses in parallel and two bus switch units. By controlling these units, the clusters can be combined in pipeline and/or parallel forms. Each cluster also uses a variable delay unit which achieves up to one frame delay on the feedback bus. By using this unit, interframe processing can be carried out without using internal data memories in VSPMs for the frame delay. The employment of the bus switches and the variable delay unit increases flexibility for a variety of signal processing algorithms. The system performs 500 million operations per second and is currently used as a real-time evaluation system for low-bit-rate picture encoders