【摘要】：傳統(tǒng)的非正方形四叉樹(shù)變換(NSQT)系數(shù)的掃描方式并不能很好地適應(yīng)系數(shù)的能量分布,這將降低熵編碼的編碼效率。為了提高編碼效率,該文提出非正方形四叉樹(shù)變換系數(shù)能量分布模型,并改進(jìn)了其系數(shù)掃描方式。首先推導(dǎo)了非正方形變換塊的空間頻率域位置分布,基于推導(dǎo)的分布,從理論上提出了其能量分布模型,并用實(shí)驗(yàn)進(jìn)行了證實(shí),發(fā)現(xiàn)能量從左上角到右下角逐漸遞減,而左下角的能量與右上角的能量接近,根據(jù)該能量分布模型,重建了非正方形四叉樹(shù)變換中量化系數(shù)的掃描模式,以適應(yīng)熵編碼,而熵編碼中的系數(shù)掃描方式傾向于系數(shù)上的降序。實(shí)驗(yàn)結(jié)果顯示,相比NSQT中已有的系數(shù)掃描方式,該文方法提出的掃描方式在編碼計(jì)算復(fù)雜度和客觀視頻質(zhì)量損失可忽略的前提下,平均下降了1.32%~3.74%的比特率,對(duì)于非正方形變換塊,下降了9.05%~13.19%的比特率。
[Abstract]:The traditional scanning method of (NSQT) coefficients of non-square quadtree transformation can not adapt to the energy distribution of coefficients well, which will reduce the coding efficiency of entropy coding. In order to improve the coding efficiency, this paper proposes a non-square quadtree transform coefficient energy distribution model, and improves its coefficient scanning method. Firstly, the spatial frequency domain position distribution of the non-square transformation block is derived. based on the deduced distribution, the energy distribution model is proposed theoretically, and the experimental results show that the energy decreases gradually from the upper left corner to the lower right corner, while the energy in the lower left corner is close to the energy in the upper right corner. According to the energy distribution model, the scanning mode of the quantitative coefficient in the non-square quadtree transform is rebuilt to adapt to the entropy coding. The coefficient scanning mode in entropy coding tends to the descending order of coefficients. The experimental results show that compared with the existing coefficient scanning methods in NSQT, the proposed scanning method reduces the bit rate by 1.32% 鈮，

本文編號(hào)：2497706