Edge Anti-Aliasing Oriented Adaptive Index Map Prediction of Screen Content
SONG Chuanming1,2, LIU Dingkun1, SUN Shiqi1, LIU Dan1
1. School of Computer and Information Technology, Liaoning Nor-mal University, Dalian 116081 2. State Key Laboratory for Novel Software Technology, Nanjing University, Nanjing 210023
Abstract：The prediction ability of the palette coding is limited in the edge anti-aliasing regions, since the adjacent indexes do not present equivalence relation. Therefore, an adaptive predictive coding method is proposed based on edge anti-aliasing decision and multiple directional templates. Eight 4-neighbor directional prediction templates are firstly designed by introducing the Pitteway anti-aliasing decision with area weight. Subsequently, a two-dimensional linear correlation model is exploited to describe the relationship between the index to be predicted and its four reference pixels. Finally, the least square method is applied to calculate a group of weight coefficients for each directional template. The anti-aliasing algorithm executed by the display adapter is adaptively learned, and thus the predictive coding of the index map is realized. Experiments show that the proposed method achieves a higher prediction accuracy and the adaptive prediction ability of the palette coding in the anti-aliasing regions and complex edge regions is improved.
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2021, Vol. 34 
