一种屏幕内容编码帧间模式快速选择算法

屏幕内容编码(SCC)作为高效视频编码(HEVC )的扩展,在压缩屏幕内容方面有着显著的效果, 但也导致了编码器计算复杂度较高的问题。为此,本文提出一种屏幕内容编码帧间模式快速 选择算法。首 先,根据像素点亮度值的变化情况,提前判断出静止区域并使用Skip模式；其次,根据屏幕 内容多包含有 水平及竖直边缘的特点,利用编码单元(CU)的水平及竖直活动性确定相应的预测单元(PU )划分模式, 减少帧间预测时需要遍历的PU个数；最后,根据时空域相邻CU的深度信息预测当前CU的深度 范围,跳 过不必要的深度遍历。实验结果表明,与SCM-8.0相比,在随机接入与低延时两种编码模式 下,本文所提 算法分别节省43.6%和49.09%的编码时间,码 率分别上升3.06%和3.43%,视频质量几乎不变 。

A fast inter mode selection algorithm for screen content coding

To reduce the computational complexity,a fast inter mode selection algorithm for screen conte nt coding (SCC) is proposed in this paper.First,the change of luminance values between current pi xel and its co-located pixel is utilized to detect static regions and Skip mode is applied. Next,given that a large number of horizontal and vertical edges occur in screen content,corresp onding prediction unit (PU) partition modes are selected according to coding unit (CU) activity,an d the number of PU modes for inter prediction can be reduced.Finally,depth range of current CU is predicted by utilizing the CU depths of adjacent CUs in both temporal and spatial domains, and unnecessary depths are skipped.Experimental results show that compared with SCM-8.0ancho r,the proposed algorithm can save 43.6% and 49.09% encoding time on average with 3.06% and 3.43% BD-rate loss for random access and low delay configurations,respectively,while the loss of v ideo quality can be negligible.Therefore,this study shows a certain reference value for the real-ti me application of SCC.