Image coding based on quadtree-structured recursive least-squares approximation

The author describes the concept of recursive oblique plane decomposition (ROPD), which circumvents the problem of setting up large-area normal equations for computation of plane parameters in model-based variable-block-size image coding and constitutes the basis for extremely fast model-based adaptive variable-block-size image coding algorithms. He presents an algorithm of this type, where ROPD is embedded in an adaptive bottom-up quadtree segmentation structure. Excellent coding results have been obtained with this technique for a set of typical natural grey-level images. An example of a variable-block-size ROPD coded image is shown