Texture coding on arbitrarily shaped image segments : transform methods*

Abstract

The new generation of image sequence coders - the object-oriented coders-consist in describing the sequence as a set of moving objects, of arbitrary size and shape. This approach allows the development of new object-based functionalities. One of the main problems to be solved in region-based coding is the coding of the texture of the objects. As for the classical block-based coding, a linear transform can be used to eliminate the input signal redundancies. This article describes transform methods for arbitrarily shaped regions of support, classified into two categories : the shape-adaptive methods and the extrapolation methods. The main differences between these two classes are discussed and the points that need further investigation are raised.