标题: | HEVC视窗视讯编码画面内区块复制技术之研究 Studies on Intra Block Copy Technique for HEVC Screen Content Coding |
作者: | 郭哲玮 Kuo, Che-Wei 杭学鸣 Hang, Hsueh-Ming 电子工程学系 电子研究所 |
关键字: | 视讯压缩;高效率视讯编码;视窗视讯编码;画面内区块复制;video coding;HEVC;Screen Content Coding;SCC;Intra Block Copy;IBC |
公开日期: | 2015 |
摘要: | 随着网路与电脑的普及,电脑影像的压缩与传输亦日渐重要。为了满足其广泛的应用需求,如远端桌面,视讯会议,远距教学,云端游戏与计算等,国际标准委员会Joint Collaborative Team on Video Coding正在制定视窗视讯编码标准,作为高效率视讯编码(High Efficiency Video Coding, HEVC)的延伸之一。 本论文研究HEVC视窗视讯编码画面内区块复制(Intra Block Copy, IBC)之技术。其核心概念相似于画面间移动补偿,仅不同于使用当前画面作为参考画面。我们对IBC相关议题,如区块向量的传输、编码效能与时间复杂度、及所需的记忆体存取频宽之间的取舍进行研究。我们特别关注在SCM-3.0标准软体中的IBC杂凑搜索方法,藉由收集现行杂凑表的编码数据资料,检查其效率并探讨进一步改进的可能性。我们提出筛选有效的杂凑节点与一改良的杂凑函式演算法。实验结果显示,将本算法整合至视窗视讯编码测试平台SCM-3.0时,其减少了10%至70%的杂凑表的记忆体使用量,且几乎对位元率和编解码时间无影响。 With the popularity and development of digital terminals, the demands for screen content video compression and transmission grow up. To meet a wide range of needs for video applications such as remote desktop, video conference, distance education, cloud gaming and computing, the ISO/ITU Joint Collaborative Team on Video Coding committee is further specifying the Screen Content Coding (SCC) standard, as one of the extensions of High Efficiency Video Coding (HEVC). In this thesis, the adopted Intra Block Copy (IBC) coding tool for HEVC Screen Content Coding is studied. The concept of IBC is essentially the same as motion compensation, except that the current frame is used as the reference. Issues of IBC such as the block vector signaling, the trade-off between coding performance and time complexity, and the required memory fetching bandwidth are investigated. Particularly, we look into the IBC hash search method in SCM-3.0 test model. We collect the coded data using the current hash table and examine their efficiency and explore possible ways for further improvement. A scheme of selecting effective hash nodes and a modified hash key generation method are presented. Experimental results show that the proposed method reduces 10% to 70% hash table memory usage but preserve the similar BD-rate savings and encoding complexity, when integrated into the SCM-3.0 test model. |
URI: | http://140.113.39.130/cdrfb3/record/nctu/#GT070250216 http://hdl.handle.net/11536/127057 |
显示于类别: | Thesis |