| Abstract: | A rate-distortion framework is used to define a very low-bit-rate coding scheme based on wireframe model adaptation and optimized selection of motion estimators. This technique achieves maximum reconstructed image quality under the constraint of a target bit rate for the coding of the vector field and the wireframe representation information. First, a complete scheme is proposed for hybrid two-dimensional (2D) and 3D motion estimation and compensation. The wireframe adaptation and updating is optimized for hybrid motion estimation in the rate distortion sense. A more sophisticated technique, adapted to the requirements of a very low-bit-rate coder is also proposed which considers also the transmission of the prediction error corresponding to the particular choice of the motion estimator for each object in the scene. Experimental results illustrating the performance of the proposed techniques in very low-bit-rate image sequence coding application areas are presented and evaluated. © 1998 John Wiley & Sons, Inc. Int J Imaging Syst Technol, 9, 238–247, 1998 |
