OPTIMAL REPRESENTATIONS IN MULTITREE DICTIONARIES WITH APPLICATION TO COMPRESSION.

We generalize our results of [8, 9] and propose a new framework of multitree dictionaries which include many previously proposed dictionaries as well as many new, very large, treestructured dictionaries. We present an efficient, globally optimal algorithm to find the best tree in such a dictionary. We describe a novel block image coder based on our framework, which is an improvement over our image coder presented in [8]. 1. INTRODUCTION. This paper focuses on optimal representation problems: given a signal, a dictionary of representations, and a cost function, the aim is to select the representation from the dictionary which minimizes the cost for the given signal