The effects of lip synchronization in IP conferencing

In multimedia IP conferencing, audio and video are separate streams of data, routed separately through the network. Packets that are transmitted simultaneously are not guaranteed to arrive at the same time at their destination, and hence, cause lip synchronization (lip sync) error. This paper focuses upon investigating the effects of lip sync on the perceived quality of audio and video in desktop videoconferencing, over two different task performances namely passive communications and interactive communications. This is because, it has been stated previously that different tasks performed by the end user will require different levels of audio and video quality.