His current research interests include human activity recognition, 3D face modeling and animation, and multimedia signal processing. He has worked on a variety of topics including Steiner trees, average case complexity, linked figure animation, and trimmed NURBS tessellation for large CAD model visualization. He was a co-chair of the IEEE International Workshop on Multimedia Technologies in E-Learning and Collaboration (Oct. 17, 2003, Nice, France), a program co-chair of 2006 IEEE International Workshop on Multimedia Signal Processing (MMSP-06), Victoria, Canada, a media co-chair of 2007 International Conference on Multimedia and Expo (ICME07), Beijing, China, and a Technical Program Co-Chair of 2010 IEEE International conference on Multimedia and Expo (ICME2010), Singapore. He is a general co-chair of 2012 IEEE Visual Communication and Image Processing, San Diego, and a program co-chair of 2014 IEEE International Conference on Multimedia and Expo (ICME 2014). He has served in the technical committee for many international conferences. He was a member of the Audio and Electroacoustics Committee of IEEE Signal Processing Society. He is the elected secretary of the Multimedia Systems and Applications Technical Committee of CAS society. He is a Co Editor-in-Chief of Journal of Visual Communications and Image Representation, and an associate editor of Machine Vision and Applications. He served as a guest editor of IEEE Transactions on Multimedia, and a guest editor of IEEE Multimedia Magazine. He is an affiliate professor in the department of Electrical Engineering, University of Washington. He is an IEEE distinguished lecturer from 2015-2016. He is a fellow of IEEE.