Optimized Index Assignment with Bi-directional Prediction in Palette Coding
SONG Chuanming1,2, CHEN Guisheng1,3, HE Xing1, FU Bo1, WANG Xianghai1
1.School of Computer and Information Technology, Liaoning Normal University, Dalian 116081 2. School of Computer Science and Technology, Dalian University of Technology, Dalian 116024 3. College of Computer Science and Technology, Jilin University, Changchun 130012
Abstract In palette coding, the research on influence of index assignment on the coding efficiency of index map is insufficient. An optimized index assignment algorithm is proposed in this paper. With the bidirectional feedback between the index map generation and prediction, the index assignment is optimized by forward prediction, backward prediction and joint probability maximization. Thus, it is easier to predict index map accurately, and the efficiency of palette coding is improved. Experimental results show that the proposed algorithm increases the prediction accuracy of the local directional prediction algorithm compared with the multi-stage prediction algorithm.
About author:: (SONG Chuanming, born in 1980, Ph.D., associate professor. His research inte-rests include image and video coding.) (CHEN Guisheng(Corresponding author), born in 1985, Ph.D. candidate. His research interests include screen content coding and intelligent information processing.) (HE Xing, born in 1990, master student. His research interests include screen content coding.) (FU Bo, born in 1983, Ph.D., lecturer. His research interests include image enhancement and computer vision.) (WANG Xianghai, born in 1965, Ph. D., professor. His research interests include multimedia information processing, computer graphics, and remote sensing information processing.)
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2017, Vol. 30 
