A Motion Compensation Algorithm Based On Non Linear Geometric Transformations And Quadtree Decomposition

In this paper we present an efficient very low bit rate coder for CIF image sequences at 10 frames/s. The proposed algorithm performs motion compensation using a second order geometric transformation and a quadtree structure. High compression ratios have been reached adapting the features of the transformation and the block size to the motion. A linear transformation is used when there is translational motion, while a non linear transformation is applied when a block has to be warped. In addition the block size is increased in homogeneous zones and reduced in detailed moving zones. Simulation results show that the proposed coding method improves the predicted images quality and reduces the blocking artifacts with respect to traditional hybrid block based techniques. 1 INTRODUCTION Very low bit rate image sequence coding is very important for video transmission and storage application. There are many practical applications of this kind of coder, ranging from video transmission by narro..