计算机科学与技术系

Department of Computer Science and Technology

Education background

Bachelor of System Engineering, National University of Defense Technology, Changsha, China, 1995;

Ph.D. in System Engineering, National University of Defense Technology, Changsha, China, 2000.

Social service

China Computer Federation: Secretary-General of Multimedia Committee (2007-).

Areas of Research Interests/ Research Projects

Multimedia and Networks

Virtual Reality

National Natural Science Foundation of China: Research on Interactive Multi-View Video Coding Technology (2006-2008);

National Basic Research Program of China (The 973 Program): Visual Media Representation, Analysis and Utilizing (2006-2010);

National 863 High-Tech Program (The 863 Program): Research on Key Technologies of Internet Free-View Video (2006-2008);

National 863 High-Tech Program (The 863 Program): Research on Key Technologies and System of Interactive Free-View 3DTV (2009-2010).

Research Status

My research group addresses fundamental problems of 3D video representation, interaction, codec and transmission, carrying the objective of providing interactive immersive multimedia application in future Internet.

We built a statistical link model for application- layer multicast and discovered that the congestion of the neighboring link layer has Markov properties. By studying the logs of practical VoD broadcasting systems and P2P live broadcasting systems, my group established a model for users' online time and their prospective activities during that time. We also theoretically analyzed the bandwidth utilization optimality of pull-based p2p streaming systems, and proposed a push-pull model for p2p streaming data scheduling, which reduced the delay and control overhead, while maintaining optimal bandwidth utilization.

We proposed a multi-view video coding scheme, which supports random accesses among views. Compared with traditional methods, our scheme improves the coding efficiency up to 2-3 db, while reducing the delay of view switching. Based on the theory of directed acyclic graph, my group designed a spatial-temporal data paralleling algorithm for multi-view video coding over multi-core processor architecture, which achieves an approximate linear speed-up. Also, an accurate estimation model for the multi-core media processing task scheduling is established by abstracting the critical properties of multimedia applications and multi-core processors. Utilizing the correlation of data between different views, I proposed a collaborative hybrid overlay network structure for large-scale multi-view video streaming of 3DTV systems.

Honors And Awards

IEEE Trans. On Circuits and Systems for Video Technology: Best Paper Award (2010).

Academic Achievement

[1] Yi Pang, Lifeng Sun, Weidong Hu, Shiqiang Yang, A Framework for Heuristic Scheduling for Parallel Processing on Multicore Architecture: A Case Study with Multiview Video Coding, IEEE Trans. On Circuits and Systems for Video Technology special issue on Algorithm/Architecture Co-Exploration of Visual Computing, VOL. 19, NO. 11, 2009. Best Paper Award.

[2] Peng Cui, Li-Feng Sun, Fei Wang, Shi-Qiang Yang, Contextual Mixture Tracking, IEEE Transactions on Multimedia, vol. 11, no. 2, pp. 335-344, 2009.

[3] Meng Zhang, Qian Zhang, Lifeng Sun, Shiqiang Yang, Understanding the Power of Pull-based Streaming Protocol: Can We Do Better IEEE Journal on Selected Areas in Communications, VOL. 25 No. 9, pp. 1-15, 2007.

[4] Meng Zhang, Yongqiang Xiong, Qian Zhang, Lifeng Sun, Shiqiang Yang: Optimizing the Throughput of Data-Driven Peer-to-Peer Streaming. IEEE Trans. On Parallel Distributed System. Vol.20, No.1, pp. 97-110, 2009.

[5] Sun, Lifeng; Liang, Ke; Ouyang, Juntao; Zhong, Yuzhuo, An energy-aware cooperative distributed video coding scheme for ad hoc video sensor network, Chinese Journal of Electronics, Vol.16 No.3, pp. 379-384, 2007.

[6] SUN Li-feng, LI Fang, ZHONG Yu-zhuo, YANG Shi-qiang, Multiview Video Based Virtual Teleconferencing Synthesizing, Journal of Electronics, Vol.33 No.2, pp. 193-196, 2005(in Chinese).

[7] Yi PANG, Jiangtao WEN, Lifeng SUN, Weidong HU, Shiqiang YANG, Frame-level Heuristic Scheduling Multi-view Video Coding on Symmetric Multi-core Architecture, IEEE International Conference on Image Processing (ICIP), Nov, 2009, Cairo, Egypt.

[8] Zhibo CHEN, Meng ZHANG, Lifeng SUN, Shiqiang, YANG, OVERLAY COLLABORATION TOWARDS MINIMIZED BANDWIDTH COSTS IN MULTI-VIEW STREAMING, IEEE ICASSP2009, Taiwan May, 2009.

[9] Meng Zhang, Lifeng Sun, Xiaolu Xi, Shiqiang Yang: iGridMedia: Providing Delay-Guaranteed Peer-to-Peer Live Streaming Service on Internet. GLOBECOM, pp. 1741-1745, 2008.

[10] PANG Yi, SUN Lifeng and YANG Shiqiang, Spatial and Temporal Data Parallelization of Multi-view Video Encoding Algorithm, Greece, IEEE Workshop on Multimedia Signal Processing (MMSP2007), 2007,10, Best Student Paper Candidates.

[11] Lifeng Sun, Yuzhuo Zhong, Zhun Zhong, Natural Interaction Synthesizing in Virtual Teleconferencing, IEEE International Conference on Image Processing(ICIP), pp. 405-408, 2002.