Image Number 4 for United States Patent #5351095.
A method for estimating motion which calculates a priori for a current image a first field of motion for blocks of a first level resulting from a partition of the image into blocks of a so-called maximum size, on the basis of a symmetric estimation algorithm, using the preceding and following images in the sequence to calculate the displaced inter-raster differences. Then, a second field of motion for blocks resulting from the partition of a block of the first level are calculated, and so on until a level of blocks of a minimum size. The final field of motion results from the selection of the most suited motion vectors from those of the various levels and is directly associated with a quadtree coding tree. Such a method finds particular application to image transmission chains, and in particular high-definition.