Patent ID: 6081553
Filing Date: 2000-06-27
Classification: H04N

Abstract:
A method for operating a data processing system to compress a first frame in an ordered sequence of image frames, said first frame being preceded by a second frame in said sequence of frames and said second frame being preceded by a third frame in said sequence of frames, each frame comprising a plurality of processing blocks, said method comprising the steps of:determining a displacement vector for at least one block in said second frame, said displacement vector identifying a region in said third frame, said identified region being an approximation of that block in said second frame;determining an approximation for a displacement vector associated with one of said blocks in said first frame, said approximation depending on said determined displacement vector in said second frame;utilizing said determined approximation to define a search region in a frame preceding said first frame corresponding to said block for which said approximation was determined, said search region comprising a plurality of sub-regions, each of said sub-regions having the same size as that block;searching said search region for said sub-region in said search region that best approximates said corresponding block in said first frame thereby determining a displacement vector in said first frame; anddetermining a displacement vector for a block in each frame preceding said first frame in said ordered sequence, said determined displacement vector in each frame identifying the region in a preceding frame that best approximates that block, and wherein said step of determining an approximation for said displacement vector comprises forming a weighted combination of displacement vectors from at least one of two of said frames preceding said first frame.