Keng Tiong Tan is a Senior Lecturer in the Faculty of Computing, Health and Science at Edith Cowan University, Australia. In 1995 he won the Institute of Engineers Australia Medal. Douglas Chai is a Senior Lecturer in the School of Engineering and Director of the Visual Information Processing Research Group at Edith Cowan University. His current research interests include image processing, video coding, facial image analysis, document imaging and multimedia communications. Hiroko Kato recently completed her Ph.D. in the School of Engineering at Edith Cowan University. Her research involved developing a novel colour 2D barcode.