结合内容特性与纹理类型的HEVC-SCC帧内预测快速算法

本文提出了一种结合内容特性与纹理类型的HEVC-SCC帧内预测快速算法。利用自然内容和屏幕内容视频DCT变换后系数能量分布不同的特点，结合当前预测单元（Prediction Unit, PU）梯度信息，将编码树单元（Coding Tree Unit, CTU）分成自然内容CTU，简单屏幕内容CTU和复杂屏幕内容CTU。对于自然内容CTU，选择35种传统帧内模式作为候选模式，跳过帧内块复制（Intra Block Copy, IBC）和调色板（Palette mode, PLT）模式；对于简单屏幕内容CTU，选择DC，PLANAR，水平和垂直模式作为候选模式，跳过IBC和PLT模式；对于复杂屏幕内容CTU，选择IBC和PLT模式，跳过其他候选模式。实验结果表明，在全I帧条件下，该算法相较于SCM-8.3可以节省38.55%的编码时间，大幅度降低了编码复杂度的同时只增加了1.82%的码率。 

Fast Intra Prediction Algorithm for HEVC-SCC Based on the Content Property and Texture Mode

A fast intra prediction algorithm for HEVC-SCC based on the content property and texture mode is proposed.Since the DCT coefficients energy distribution of screen content video is differ from the natural content ones,early decision of video content is helpful to skip some prediction modes.With gradient information of prediction unit(PU),coding tree units(CTUs)can be classified into natural content CTUs(NCCTU),smooth screen content CTUs(SSCTU)and complex screen content CTUs(CSCTU).For NCCTU,traditional 35 intra modes are selected as candidates,and the Intra Block Copy(IBC)and Palette(PLT)modes are skipped;for SSCTU,DC mode,PLANAR mode,horizontal angle mode and vertical angle mode are selected as candidates,while the IBC and PLT modes are skipped;for CSCTU,the IBC and PLT modes are used for prediction and skip traditional intra modes.Under all-intra(AI)configuration,experimental results show that the proposed algorithm can achieve encoding time saving by 38.55%compared with SCM- 8.3,and the bit rate only increases 1.82%.