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研究生： 胡瑞峰
Hu, Jui-Feng
論文名稱： 加速HEVC編碼單元的四分樹結構與編碼模式之抉擇
Speeding up the Decisions of Quad-Tree Structures and Coding Modes for HEVC Coding Units
指導教授： 戴顯權
Tai, Shen-Chuan
學位類別： 碩士
Master
系所名稱： 電機資訊學院 - 電腦與通信工程研究所
Institute of Computer & Communication Engineering
論文出版年： 2012
畢業學年度： 100
語文別： 英文
論文頁數： 61
中文關鍵詞： HEVC 、編碼單元 、四分樹結構 、編碼模式 、快速演算法
外文關鍵詞： High Efficiency Video Coding, Coding Unit, Quad-Tree Structure, Coding Mode, Fast Algorithm
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    • HEVC(High Efficiency Video Coding)是一個發展中的視訊編碼標準，目前正由ISO/IEC MPEG及ITU-T VCEG所共同開發，HEVC也被認為是H.264/AVC的後繼者並被預期在未來會成為熱門的新一代視訊編碼標準。HEVC以編碼單元(Coding Unit)組成的樹狀結構代替了巨方塊(Macroblock)策略，編碼程序在這個四元樹的結構上遞迴式地檢驗了所有可能的大小編碼單元，這樣的程序可以評估各種大小編碼單元的編碼效能並保留最佳的編碼單元分割。HEVC可以提供比H.264/AVC標準更高的壓縮比，然而，編碼的複雜度也顯著地提升了。在本論文中提出了一套針對編碼單元決策之快速演算法，以降低HEVC 在編碼時間上的負擔。演算法利用視訊串流中相鄰畫面的時間相關性來避免在編碼單元四元樹上不必要的運算。此外，根據一個可調式的閥值，最佳的預測模式可被提早決定為SKIP模式並減少在預測階段中繁複的運算。演算法的效能以HEVC的測試模組(HM)5.0驗證，實驗結果顯示，在Low-Delay High Efficiency、Low-Delay Low Complexity、Random-Access High Efficiency與Random-Access Low Complexity等設定下，演算法可分別達到平均約27%、33%、20%與21%的編碼時間節省量，並只伴隨著在編碼效能上微小的衰減。

    High Efficiency Video Coding (HEVC) is a ongoing video coding standard which is currently under the joint development of ISO/IEC MPEG and ITU-T VCEG. HEVC is also known as the successor of H.264 video coding standard and is expected to be a popular next-generation video codec in the future. HEVC replaces macroblock scheme with coding units (CUs) in the form of quad-tree structure. The encoding process examines all possible CUs recursively on the quad-tree. This process can evaluate the coding performance for the variable sized CUs and retain the best partitions of the CUs. HEVC can provide higher compression ratio compared to H.264/AVC standard; however, the coding complexity is dramatically increased as well. In this thesis, a fast algorithm for coding unit decision is proposed to reduce the burden of the encoding time in HEVC. The proposed algorithm exploits the temporal correlation in the neighboring frames of a video sequence to avoid the unnecessary examinations on CU quad-trees. In addition, based on an adaptive threshold, the best prediction mode is early determined to SKIP mode for reducing the exhaustive evaluations at prediction stage. The performance of the proposed algorithm is veri ed through the test model for HEVC, HM 5.0. The experimental results show that the proposed algorithm can averagely achieve about 27%, 33%, 20%, and 21% total time encoding time reduction under Low-Delay High Effi ciency, Low-Delay Low Complexity, Random-Access High Effi ciency, and Random-Access Low Complexity con gurations respectively with a negligible degradation of coding performance.

    摘要. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . i Abstract . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . ii Acknowledgements . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . iv Table of Contents . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . v List of Tables . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . vii List of Figures . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . ix 1 Introduction . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 1 1.1 Overview of Video Compression . . . . . . . . . . . . . . . . . . . . . . 1 1.2 Progress of High Eciency Video Coding . . . . . . . . . . . . . . . . . 2 1.3 Motivation and Objective . . . . . . . . . . . . . . . . . . . . . . . . . 2 1.4 Organization of This Thesis . . . . . . . . . . . . . . . . . . . . . . . . 3 2 Background and Related Works . . . . . . . . . . . . . . . . . . . . . . . . . 5 2.1 Overview of HEVC . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 5 2.1.1 Coding Unit (CU) . . . . . . . . . . . . . . . . . . . . . . . . . 8 2.1.2 Prediction Unit (PU) . . . . . . . . . . . . . . . . . . . . . . . . 9 2.1.3 Transform Unit (TU) . . . . . . . . . . . . . . . . . . . . . . . . 12 2.1.4 Rate-Distortion Optimization Routine . . . . . . . . . . . . . . 13 2.1.5 Inter Prediction . . . . . . . . . . . . . . . . . . . . . . . . . . . 18 2.1.6 Intra Prediction . . . . . . . . . . . . . . . . . . . . . . . . . . . 20 2.2 Previous Methods for Fast CU Decision . . . . . . . . . . . . . . . . . . 22 2.2.1 Condition-Based Methods . . . . . . . . . . . . . . . . . . . . . 22 2.2.2 Content-Aware Algorithms . . . . . . . . . . . . . . . . . . . . . 24 3 The Proposed Algorithm . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 26 3.1 Coding Unit Quad-Tree Pruning Method . . . . . . . . . . . . . . . . . 26 3.2 Early SKIP Mode Decision . . . . . . . . . . . . . . . . . . . . . . . . . 38 3.3 The Enhanced Proposed Algorithm . . . . . . . . . . . . . . . . . . . . 41 4 Experimental Results . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 43 4.1 Assessment . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 43 4.2 Experiments of the Proposed Algorithm . . . . . . . . . . . . . . . . . 44 4.3 Experiments of the Enhanced Proposed Algorithm . . . . . . . . . . . . 57 5 Conclusions and Future Works . . . . . . . . . . . . . . . . . . . . . . . . . . 59 References . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 60

    [1] Information tecchonology: Generic coding of moving pictures and associated audio information, Std., 1995.
    [2] Advanced video coding for generic audiovisual services, Std., 2007.
    [3] G. Bjontegaard, "Calculation of average PSNR differences between RD-curves," ITU-T VCEG-M33, 2001.
    [4] F. Bossen, HM reference software 5.0, 2011. [Online]. Available: https://hevc.hhi.fraunhofer.de/svn/svn_HEVCSoftware/
    [5] F. Bossen, Common HM test conditions and software reference configurations, Jan. 2012. [Online]. Available: http://phenix.int-evry.fr/jct/doc end user/documents/7_Geneva/wg11/JCTVC-G1200-v2.zip
    [6] B. Bross, W.-J. Han, G. J. Sullivan, J.-R. Ohm, and T. Wiegand, High Efficiency Video Coding (HEVC) text speci cation Working Draft 5, Feb. 2012. [Online]. Available: http://phenix.int-evry.fr/jct/doc_end_user/documents/7_Geneva/wg11/JCTVC-G1103-v12.zip
    [7] K. H. Choi and E. S. Jang, "Coding tree pruning based cu early termination," Jul. 2011. [Online]. Available: http://phenix.int-evry.fr/jct/doc end user/documents/6_Torino/wg11/JCTVC-F092-v3.zip
    [8] C. K. Chung and S. C. Tai, "Fast qp-adaptive multiple reference frames mode decision algorithm for h.264/avc," Jun. 2006.
    [9] G. Correa, P. Assuncao, L. Agostini, and L. da Silva Cruz, "Complexity control of high efficiency video encoders for power-constrained devices," Consumer Electronics, IEEE Transactions on, vol. 57, no. 4, pp. 1866-1874, Nov. 2011.
    [10] R. H. Gweon, Y. L. Lee, and J. Y. Lim, "Early termination of cu encoding to reduce hevc complexity," Jul. 2011. [Online]. Available: http://phenix.int-evry.fr/jct/doc end user/documents/6_Torino/wg11/JCTVC-F045-v1.zip
    [11] S. Y. Jeong, S. C. Lim, H. Y. Lee, J. H. Kim, J. S. Choi, and H. C. Choi, "Highly efficient video codec for entertainment-quality," ETRI Journal, vol. 33, pp. 145-154, Apr. 2011.
    [12] J. H. Kim, S. Y. Jeong, S. H. Cho, and J. S. Choi, "Adaptive coding unit early termination algorithm for hevc," in Consumer Electronics (ICCE), 2012 IEEE International Conference on, Jan. 2012, pp. 261-262.
    [13] J. Leng, L. Sun, T. Ikenaga, and S. Sakaida, "Content based hierarchical fast coding unit decision algorithm for hevc," in Multimedia and Signal Processing (CMSP), 2011 International Conference on, vol. 1, May. 2011, pp. 56-59.

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