Coding mode optimization for MPEG-2 transcoding with spatial resolution reduction

This paper presents a coding mode decision algorithm for MPEG-2 spatial transcoding. The optimization for coding mode and quantization scale are formulated in an operational rate distortion sense and solved by Lagarange multiplier method. The experimental results show that the proposed transcoder with optimized coding mode and quantizer can achieve better quality and lower bit rate than those obtained using cascaded transcoder or MPEG-2 TM5 encoder. This work may not be copied or reproduced in whole or in part for any commercial purpose. Permission to copy in whole or in part without payment of fee is granted for nonprofit educational and research purposes provided that all such whole or partial copies include the following: a notice that such copying is by permission of Mitsubishi Electric Research Laboratories, Inc.; an acknowledgment of the authors and individual contributions to the work; and all applicable portions of the copyright notice. Copying, reproduction, or republishing for any other purpose shall require a license with payment of fee to Mitsubishi Electric Research Laboratories, Inc. All rights reserved. Copyright c ©Mitsubishi Electric Research Laboratories, Inc., 2003 201 Broadway, Cambridge, Massachusetts 02139 Publication History: 1. First printing, TR-2003-99, August 2003 Coding Mode Optimization for MPEG-2 Transcoding with Spatial Resolution Reduction Hao-Song Kong, Anthony Vetro, and Huifang Sun Mitsubishi Electric Research Laboratories 201 Broadway, Cambridge, MA 02139, USA [email protected]; [email protected]; [email protected] ABSTRACT This paper presents a coding mode decision algorithm for MPEG-2 spatial transcoding. The optimization for coding mode and quantization scale are formulated in an operational rate distortion sense and solved by Lagarange multiplier method. The experimental results show that the proposed transcoder with optimized coding mode and quantizer can achieve better quality and lower bit rate than those obtained using cascaded transcoder or MPEG-2 TM5 encoder. Keyword: MPEG-2 transcoding, spatial resolution reduction, coding mode decision, Lagrangian minimization, motion vector re-samplingThis paper presents a coding mode decision algorithm for MPEG-2 spatial transcoding. The optimization for coding mode and quantization scale are formulated in an operational rate distortion sense and solved by Lagarange multiplier method. The experimental results show that the proposed transcoder with optimized coding mode and quantizer can achieve better quality and lower bit rate than those obtained using cascaded transcoder or MPEG-2 TM5 encoder. Keyword: MPEG-2 transcoding, spatial resolution reduction, coding mode decision, Lagrangian minimization, motion vector re-sampling