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EURASIP Journal on Applied Signal Processing 2003:3, 244–251 c 2003 Hindawi Publishing

EURASIP Journal on Applied Signal Processing 2003:3, 244–251 c 2003 Hindawi Publishing Corporation An Adaptive Video Coding Control Scheme for Real-Time MPEG Applications Shih-Chang Hsia Department of Computer and Communication Engineering, National Kaohsiung First University of Science and Technology, Kaohsiung 824, Taiwan Email: hsia@ccms.nkfust.edu.tw Received 27 February 2002 and in revised form 16 September 2002 This paper proposes a new rate control scheme to increase the coding efficiency for MPEG systems. Instead of using a static group of picture (GOP) structure, we present an adaptive GOP structure that uses more P- and B-frame coding, while the temporal correlation among the video frames maintains. | EURASIP Journal on Applied Signal Processing 2003 3 244-251 2003 Hindawi Publishing Corporation An Adaptive Video Coding Control Scheme for Real-Time MPEG Applications Shih-Chang Hsia Department of Computer and Communication Engineering National Kaohsiung First University of Science and Technology Kaohsiung 824 Taiwan Email hsia@ccms.nkfust.edu.tw Received 27 February 2002 and in revised form 16 September 2002 This paper proposes a new rate control scheme to increase the coding efficiency for MPEG systems. Instead of using a static group of picture GOP structure we present an adaptive GOP structure that uses more P- and B-frame coding while the temporal correlation among the video frames maintains high. When there is a scene change we immediately insert intramode coding to reduce the prediction error. Moreover an enhanced prediction frame is used to improve the coding quality in the adaptive GOP. This rate control algorithm can both achieve better coding efficiency and solve the scene change problem. Even if the coding bit rate is over the predefined level this coding scheme does not require re-encoding for real-time systems. Simulations demonstrate that our proposed algorithm can achieve better quality than TM5 and satisfactory reliability for detecting scene changes. Keywords and phrases control strategy MPEG rate control scene change temporal correlation. 1. INTRODUCTION Recently the video coding systems have been widely applied to digital TV video conferencing multimedia systems and so forth primarily in order to reduce the bit rates 1 2 3 . It is well known that most coding techniques will generate variable bit rates in various video sequences. To transmit the variable rate bit stream over a fixed rate channel a channel buffer is required. Therefore the main purpose of the rate control algorithm is to prevent the buffer from overflowing and underflowing and to generate a constant bit rate for targets. To regulate the fluctuation of the coding rate we need to .