Improved video quality for low bit rate video conferencing

• Main Author: Kittisak Intharaphithak.
• Other Authors: Ang Yew Hock
• Format: Theses and Dissertations
• Language: English
• Published: 2009
• Subjects: DRNTU::Engineering::Electrical and electronic engineering::Wireless communication systems
• Online Access: http://hdl.handle.net/10356/18840
• Institution: Nanyang Technological University

Video telephony has gained wider commercial interest within the recent years, especially with the greater availability of high speed public IP network. However there still exist many low capacity networks including mobile networks, and hence effective video coding techniques are necessary to deliver quality video information at low bit rates. This project seeks to improve the video coding efficiency and the overall video quality with respect to low bit rate video conferencing. It exploits human visual properties in digital video perception to improve on existing video coding techniques. This report first outlines the common block-based video coding techniques and related issues with respect to low bit rate applications. The rest of the paper then focuses on solving some of the problems identified in the existing systems. Common rate control algorithms aim at meeting bandwidth requirements by sacrificing visual quality. However at very low bit rate, the visual quality is usually unacceptable due to high compression. The problem is that these algorithms do not prioritize different parts of the information being encoded according to the human visual system, thus compression is being applied ineffectively.