摘要
预测编码技术通过空间域的信号预测以及时间域的运动预测补偿,消除视频图像的空间和时间相关性信息冗余,从而减少视频信号表示需要的数据量,是数字视频压缩编码的关键部分,对视频数据压缩效率及视频图像质量有深刻影响。无线视频通信应用的蓬勃发展对视频压缩编码技术特别是预测编码技术不断提出新的挑战,主要表现在:为降低对昂贵的无线网络带宽的需求,视频编码中采用了更先进、计算复杂度更高的预测编码技术以提高压缩效率,然而无线设备计算能力的不足对于预测编码算法的实时实现是一个巨大挑战;无线计算环境下计算能力的不确定性对视频编码器的自适应能力提出了更高的要求,使得预测编码技术面临计算能力变化条件下保证实时实现并维持视频质量的挑战。因此,快速高效、具有计算环境自适应能力的预测编码技术是面向无线视频应用视频编码技术的研究重点和研究热点。
本文基于当前流行的预测编码结构,重点研究了计算复杂度占主导地位的运动估计算法,从减少块匹配的次数及降低块匹配计算的复杂度两方面研究了块匹配运动估计的快速算法,并针对多参考帧运动预测技术带来的计算复杂度线性增长,研究了加速多参考帧运动估计的方法;针对多种预测模式带来的高计算复杂度,研究了加速预测模式选择的方法。另外,针对无线设备计算能力不断变化的特征,本文还研究了使运动预测具有计算复杂度可伸缩性的方法。取得的主要研究成果如下:
1.深入研究了通过减少块匹配的次数加速运动估计进程的策略,提出一种基于方向性平行四边形搜索模式的快速运动估计算法。设计了具有方向性的平行四边形搜索模式,根据预测运动矢量的位置信息判断运动的趋势,使得方向性的搜索模式与运动趋势相适应,避免了运动搜索的盲目性;采用搜索模式方向上下文自适应的搜索策略,根据当前最优点与次优点的位置关系决定搜索前进的方向、搜索模式的方向以及搜索点的选择,使得运动搜索路径与失真递减的方向一致,提高了运动搜索的效率;另外,还设计了一种预测加速度运动矢量的运动矢量预测因子,增强了运动矢量预测的性能。实验结果表明,提出的快速运动估计算法比现有的方法具有更高的计算加速性能和率失真性能。
2.深入研究了通过降低块匹配计算的复杂度加速运动估计进程的方法,提出一种基于起始搜索中心点预测的部分失真搜索快速运动估计算法。以规格化部分失真搜索算法为基础,通过对起始搜索中心点进行有效的预测,加速部分失真搜索的收敛过程;在搜索过程中引入提前结束检测机制,在起始搜索中心点预测阶段判断提前结束条件,避免了不必要的后续搜索匹配计算;根据搜索路径的特点以及不同搜索路径的失真差,设计了一种中途终止检测机制,在当前路径搜索结束后及时判断后续路径搜索的必要性,进一步减少了搜索点冗余。实验结果表明,算法在保证较高视频质量的同时,比同类型其它算法具有更高的计算加速性能;如果将提出的算法和基于方向性平行四边形搜索模式的快速算法结合使用,则能进一步提高运动估计的执行速度。
3.针对多参考帧运动预测技术带来的计算复杂度线性增长问题,提出一种基于小钻石区域选择的快速多参考帧运动估计算法。根据多参考帧运动估计的特点,设计了多参考帧条件下的运动矢量预测机制,改善了远距离参考帧的运动预测精度;分析了多参考帧条件下运动矢量的空间与时间分布特征,以此为基础设计了基于小钻石路径搜索的参考帧选择方法,它在最近参考帧之外的其余参考帧中选择最佳的候选参考帧;提出的算法只需在两个候选参考帧中执行完整的运动估计,且参考帧选择的准确性保证了最终的运动预测性能几乎不受影响。实验结果表明,提出的算法能够显著降低多参考帧运动估计的计算复杂度,同时保持了多参考运动估计的高率失真性能。
4.针对多种预测模式带来的高计算复杂度问题,提出一种层次性预测模式选择框架以及基于此框架的快速预测模式选择算法。层次性框架根据各种预测模式所代表的空间和时间特征对宏块进行层次性分类,根据当前宏块提取的特征参数在不同层次上选择合适的预测模式类型;快速预测模式选择算法以层次性框架为基础,在复杂的率失真模式选择之前,在不同的层次提取特定的特征参数,根据特征参数值选择模式类型,选择的模式类型确定了需要考察的预测模式,而未选择类型包含的模式则不需要进行率失真代价的计算。实验结果表明,提出的快速预测模式选择算法能够有效减少使用的预测模式个数,显著降低多预测模式率失真选择计算带来的高计算复杂度,同时视频编码的率失真性能损失很少。
5.针对无线设备计算能力不断变化的特点,提出一种基于层次性计算能力分配的运动预测算法计算复杂度可伸缩机制。根据运动估计按照宏块光栅扫描顺序执行的特点,在帧级计算能力约束条件下,为运动预测设计了包括初始分配、全局分配及部分分配的三层计算能力分配策略,综合利用已完成帧的信息以及当前帧执行的中间结果将计算能力有效分配到每个宏块;使用了可扩展的运动估计搜索模式,使得分配的计算能力出现冗余的情况下能够被充分利用,以进一步提高预测精度。实验结果表明,提出的可伸缩机制能够实现预测算法的精细粒度计算复杂度可伸缩性,同时保证了计算能力约束下尽可能高的总体预测精度及图像质量。
综合应用前面的研究成果,本文设计了一个视频编码器软件实现的原型系统。原型系统以H.264参考软件为基础,对其代码结构与数据结构进行了适当优化,同时集成了本文提出的算法。实验结果表明,原型系统能够获得较好的编码加速效果和率失真性能,进一步验证了本文所提出算法的实际使用性能。
By signal prediction of spatial domain and motion prediction compensation of time domain, predictive encoding technique realizes the elimination of the spatial and temporal information redundancy, and thereby reduces the volume of data needed by video signals presentation. Predictive encoding technique is a key component of the digital video compression, and has a profound impact on the compression efficiency and video quality. With wireless video communication's flourishing development, video compression technology, especially predictive encoding technology is facing a new challenge. First, to reduce the demand for expensive wireless network bandwidth, more advanced predictive encoding techniques with high computational complexity are used in video coding to increase the efficiency of compression. But the lack of computing power for wireless devices to achieve real-time predictive coding algorithm is a huge challenge. Second, in wireless computing environment, the uncertainty of computing ability puts a higher demand for the adaptive capacity of video encoders and predictive coding techniques face challenges ability to ensure the achievement and maintenance of real-time video quality in conditions of variable computing power. Therefore, fast and efficient predictive encoding techniques with the ability to adapt computing environment is research focus and study of coding technique for wireless video.
Based on the current popular predictive encoding structure, this paper focused on the study of the motion estimation algorithm which consumes most computational power, in terms of reducing both the frequency of block-matching and matching complexity of block-matching motion estimation algorithms and targeting high computational complexity of multi-reference frame motion estimation do research on the method of accelerating motion estimation. In view of the high computational complexity of a variety of prediction modes, this paper also explored methods of accelerating modes decision. Meanwhile, to meet the ever-changing characteristics of computing power of wireless devices, this paper also studied mechanism to make motion prediction have complexity scalability. The main results are as follows:
1. A fast motion estimation algorithm based on the directional parallelogram search is proposed through in-depth studies strategies of reducing the number of block-matching to accelerate motion estimation process. First, a directional parallelogram search mode is designed by which the movement trend can be judged according to the motion vector position and directional search mode can be compatible with the trend of movement, so as to avoid blindness in the search process. Second, a search strategy with context adaptivity in terms of the search mode direction is utilized, which decides search advance direction, search mode direction, and selection of search points according to the location relationship between current optimal point and suboptimal point, such that the search path is identical to the direction of distortion decreasing, consequently obtains more motion search efficiency. In addition, a motion vector predictor called acceleration prediction motion vector is designed to enhance motion vector prediction performance. The experimental results show that the proposed fast motion estimation algorithm can get higher speedup and better rate-distortion performance than existing methods.
2. A partial distortion search fast motion estimation algorithm based on initial search center predciton is proposed by study in depth methods of reducing the complexity of block-matching calculating in order to speed up the motion estimation process, which builds on the normalized partial distortion search algorithm and accelerates the convergence process of partial distortion search by means of effective initial search center prediction. An early termination detection mechanism is introduced during the search process, by which termination conditions can be judged in the phase of initial search center predciton thus subsequent unnecessary matching can be avoided. According to characteristics of the search path and distortion difference of search paths, a midway termination detection mechanism is designed, which timely judge the necessity of follow-up path search at the end of the current path search so as to further reduce search points redundancy. The experimental results show that the proposed algorithm can achieve higher speedup ratio than other similar algorithms at the same time maintaining comparable video quality. If the proposed algorithm is used combined with fast algorithm based on directional parallelogram search pattern, higher motion estimation execution speed can be obtained.
3. Aiming at computational complexity linear growth brought by multi-frame motion estimation, a fast multi-frame motion estimation algorithm based on small diamond-regional selection is proposed. First, according to the characteristics of the multi-frame motion estimation, motion vector prediction mechanism in multiple reference frames is designed to improve the accuracy of the remote reference frame. Second, based on analysis of spatial and temporal distribution characteristics of the motion vector under the conditions of multi-reference-frame, a small diamond path search-based reference frame selection method is proposed, which selects the best candidate in the remaining reference frames except for the recent one. The proposed algorithm only implements complete motion estimation in two reference frame candidates and also the accuracy of frame selection can guarantee the ultimate motion prediction performance almost unaffected. The experimental results show that the proposed algorithm can significantly reduce the computational complexity of multi-frame motion estimation, while maintaining a high rate-distortion performance coherently.
4. In view of the high computational complexity involved in multiple prediction modes, a hierarchical framework of prediction modes type judgment and a fast prediction mode decisioin algorithm based on this framework is proposed. According to the spatial and temporal characteristics of the macroblock represented by various prediction modes, macroblocks are hierarchically classified and therefore a suitable type of prediction mode for the current macroblock can be chosen at different classification levels based on extracted macroblock characteristics parameters. The fast mode decision algorithm is based on this framework and at different levels selects mode type according to specific extracted parameters before the complicated rate-distortion mode decision. Therefore, the choice of mode types determines prediction modes needed to be examined and that included in unchosen type can be skipped. The experimental results show that the prediction mode selection algorithm can reduce the number of prediction modes significantly meanwhile with little rate-distortion performance loss.
5. In view of the ever-changing characteristics of wireless devices computing power, a motion prediction algorithm complexity scalable mechanism based on hierarchical computing power allocation is proposed According to features that implementation of motion estimation in accordance with the grid scanning, under the frame-level computing power restrictions, three level computing power allocation strategy is designed for motion prediction, including the initial, global, and local allcocation, which effectively allocates computing power to each macroblock by comprehensive utilization of the information of completed frame the intermediate results of the current frame implementation. Extensible motion estimation search patterns are used to take full advantage of the allocated computation ability if redundant so as to further improve prediction accuracy. The experimental results show that the proposed mechanism can achieve fine granularity complexity scalability for prediction algorithms and ensure the highest possible overall prediction accuracy and visual quality under computing power constraints.
Integrated application of aforementioned research results, a software video encoder prototype system is designed. The prototype system is based on H.264 reference software, conducts an appropriate optimization for the code procedures and data structures, the same time integrates algorithms presented in this paper. The experimental results show that the prototype system can achieve good encoding speedup results and rate-distortion performance that further validate the the good performance of algorithms proposed by this paper.
引文
[1](奥)Andreas F.Molisch.宽带无线数字通信(英文版).北京:电子工业出版社,2002
[2]钟玉琢等.多媒体计算机技术基础及应用.高等教育出版社,2000
[3]lain E.G.Richardson.Video Codec Design.John Wiley & Sons Ltd,2002
[4]ITU-T Recommendation H.261,"Video codec for Audiovisual Services at p X 64kbit/s," March 1993.
[5]ISO/IEC 11172:"Information technology-coding of moving pictures and associated audio for digital storage media at up to about 1.5 Mbit/s," Geneva,1993.
[6]ISO/IEC 13818-2:"Generic coding of moving pictures and associated audio information--Part 2:Video," 1994,also ITU-T Recommendation H.262.
[7]ITU-T Recommendation H.263,"Video Coding for Low bit rate Communication," version 1,Nov.1995;version 2,Jan.1998;version 3,Nov.2000.
[8]ISO/IEC 14496-2:"Information technology-coding of audiovisual objects-part 2:visual," Geneva,2000.
[9]ITU-T Recommendation H.263.Video coding for low bit rate communication,version 1.Nov.1995.
[10]ISO/IEC JTC11/SC29/WG11 N2323."Overview of the MPEG-4 Standard," July 1998.
[11]钟玉琢、王琪、贺玉文.基于对象的多媒体数据压缩编码国际标准--MPEG-4及其校验模型,科学出版社,2000.
[12]章毓晋.图像处理与分析[M].北京:清华大学出版社,2001.
[13]沈兰荪,卓力等.视频编码与低速率视频传输[M].北京:电子工业出版社,2001.
[14]崔之祜,江春,陈丽鑫.数字视频处理.电子工业出版社,1998
[15]C.W.Lin,J.Zhou,J.Youn,M.T.Sun."MPEG video streaming with VCR-functionality".IEEE Tran.Circuits Syst.Video Technol.,vol.11,No.3,pp.282-300,Mar.2001.
[16]ITU-T Rec.H.264 / ISO/IEC 11496-10."Advanced Video Coding",Final Committee Draft,Document JVTG050.Pattaya,March 2003
[17]T.Wiegand,GJ Sullivan,G.Bjontegaard,A.Luthra."Overview of the H.264/AVC Video Coding Standard," IEEE Trans.Circuits Syst.Video Technol.,vol 13,pp.560-576,July.2003.
[18]T.Stockhammer,MH Hannuksela,and Y.Wiegand."H.264/AVC in Wireless Environments," IEEE Transactions on Circuits and Systems for Video Technology,Vol.13,No.7,pp.657-673,July 2003.
[19]Lappalainen,V.;Hallapuro,A.;Hamalainen,YD."Complexity of optimized H.26L video decoder implementation",vol.13,iss.7,IEEE Trans.Circuits Syst.Video Technol.,pp.717- 725,July 2003.
[20]http://www.avs.org.cn/
[21]信息技术先进音视频编码第二部分:视频,2004.
[22]信息技术先进音视频编码第七部分:移动视频,2004.
[23] T. Wiegand and G. Sullivan. "The emerging JVT/H.26L video coding standard,"presented at the Tutorial at ICIP 2002, Rochester, NY, Sept. 2002.
[24] P. Kuhn. Algorithms, Complexity Analysis and VLSI Architectures for MPEG-4 Motion Estimation, Kluwer Academic Publishers, 1999.
[25] P. Kuhn, and W. Stechele. "Complexity Analysis of the Emerging MPEG-4 Standard as a Basis for VLSI Implementation," SPIE 3308, Visual Communications and Image Processing, pp.498-509, Jan. 1998.
[26] Kuhn P. "Complexity Analysis of single video tools of the MPEG-4 verification Model", ISO/TEC JTC1/SC29/WG11/M3204, San Jose, USA, Jan. 1998
[27] Kuhn P. "A Complexity Analysis Tool: iprof (version 0.3)", ISO/IEC JTC1/SC29/WG11/M2863, Fribourg (CH), Switzerland, October 1997
[28] ftp://ftp.imtc-files.org/jvt-experts/referencesoftware/jm8.6.zip
[29] ISO/IEC JTC1/SC29/WG11 N2918, "MoMuSys Implementation of the VM (VM-991029)," Melbourne, Oct. 1999.
[30] Jorn Ostermann, et al., "Video coding with H.264/AVC: Tools, Performance, and Complexity," in IEEE Circuits and Systems Magazine, pp. 7-28, First Quarter 2004.
[31] T. Koga, K. Iinuma, A. Hirano, Y. Iijima, and T. Ishiguro, "Motion compensated interframe coding for video conferencing," in Proc. National Telecommunications Conf., New Orleans, LA, Nov. 1981, pp. G5.3.1-G5.3.5.
[32] R. Li, B. Zeng, and M. L. Liou, "A new three-step search algorithm for block motion estimation," IEEE Trans. Circuits Syst. Video Technol., vol. 4, pp.438-443, Aug. 1994.
[33] L. M. Po and W. C. Ma, "A novel four-step search algorithm for fast block motion estimation," IEEE Trans. Circuits Syst. Video Technol., vol. 6, pp.313-317,June 1996.
[34] J. Y. Tham, S. Ranganath, M. Ranganath, and A. A. Kassim, "A novel unrestricted center-biased diamond search algorithm for block motion estimation," IEEE Trans. Circuits Syst. Video Technol., vol. 8, pp. 369-377, Aug.1998.
[35] S. Zhu and K. K. Ma, "A new diamond search algorithm for fast block matching motion estimation," IEEE Trans. Image Processing, vol. 9, pp. 287-290, Feb.2000.
[36] C. H. Cheung and L. M. Po, "A Novel Cross-Diamond Search Algorithm for Fast Block Motion Estimation", IEEE Trans, Circuits Syst. Video Technol., vol. 12, no.12, Dec. 2002.
[37] C. H. Cheung and L. M. Po, "A novel small-cross-diamond search algorithm for fast video coding and videoconferencing applications", in Proc. IEEE ICIP, Sept.2002.
[38] C.W. Lam, L.M. Po, C.H. Cheung, "A Novel Kite-Cross-Diamond Search Algorithm For Fast Block Matching Motion Estimation", IEEE International Symposium on Circuits and Systems, Canada, 2004.
[39] C. Zhu, X. Lin, and L. P. Chau, "Hexagon-based Search Pattern for Fast Block Motion Estimation," IEEE Trans. on Circuits and Systems for Video Technology,vol. 12, no. 5, May 2002.
[40] Yao Nie; Kai-Kuang Ma, "Adaptive rood pattern search for fast block-matching motion estimation", IEEE trans. Image Processing, vol. 11, pp. 1442-1449, Dec 2002.
[41] Xuan-Quang Banh and Yap-Peng Tan, "Adaptive dual-cross search algorithm for block-matching motion estimation", in IEEE Transaction Consumer Electronics 2004.
[42] A.M. Tourapis, O.C. Au, and M.L. Liou, "Predictive Motion Vector Field Adaptive Search Technique (PMVFAST) - Enhancing Block Based Motion Estimation", in proceedings of Visual Communications and Image Processing 2001 (VCIP-2001), pp.883-892, San Jose, CA, January 2001.
[43] "Optimization Model Version 1.0", ISO/IEC JTC1/SC29/WG11 MPEG2000/N3324, Noordwijkerhout, Netherlands, March 2000.
[44] A.M. Tourapis, O.C. Au, and M.L. Liou, "New Results on Zonal Based Motion Estimation Algorithms - Advanced Predictive Diamond Zonal Search," in proceedings of 2001 IEEE International Symposium on Circuits and Systems(ISCAS-2001), vol.5, pp.183-186, Sydney, Australia, May 6-9,2001.
[45] A.M. Tourapis, O.C. Au,"Enhanced Predictive Zonal Search for Single and Multiple Frame Motion Estimation", Visual Communications and Image Processing 2002. 2002
[46] Z.B. Chen, P. Zhou, and Y. He, "Fast integer pel and fractional pel motion estimation for JVT," JVT-F017, 6~(th) meeting: Awaji, Japan, 5-13 Dec. 2002
[47] L. W. Lee, J. F. Wang, J. Y. Lee, and J. D. Shie, "Dynamic search-window adjustment and interlaced search for block-matching algorithm," IEEE Trans.Circuits Syst. Video Technol., vol. 3, pp. 85-87, Feb. 1993.
[48] S. Eckart, C. Fogg, ISO/IEC MPEG-2 software video codec. Proc. SPIE, vol.2419 (1995), pp. 100-118.
[49] B. Liu and A. Zaccarin, "New fast algorithms for the estimation of block motion vectors," IEEE Trans. Circuits Syst. Video Technol., vol. 3, pp. 148-157, Apr.1993.
[50] C. K. Cheung and L. M. Po, "Normalized partial distortion search algorithm for block motion estimation," IEEE Trans. Circuits Syst. Video Technol., vol.10, pp.417-422, Apr. 2000.
[51] C. K. Cheung and L. M. Po, "Adjustable partial distortion search algorithm for fast block motion estimation," IEEE Trans. Circuits Syst. Video Technol., vol.13,pp. 100-110, Jan. 2003.
[52] C.W. Ting, C.W. Lam and L.M. Po, "A Novel Early-accepted Partial Distortion Algorithm for Fast Block Matching Motion Estimation ", International Symposium on Intelligent Multimedia, Video & Speech Processing, Hong Kong,2004.
[53] A. Chang, OC An, and YM Yeung, "A novel approach to fast multi-frame selection for H.264 video coding", Proceedings of 2003 IEEE International Conference on Acoustics, Speech, and Signal Processing, ICASSP2003. Hong Kong, Apr. 6-10.
[54] C. W. Ting, L. M. Po and C. H. Cheung, "Center-Biased Frame Selection Algorithms For Fast Multi-Frame Motion Estimation in H.264", Proceeding of 2003 IEEE International Conference on Neural Networks and Signal Processing,pp. 1258-1261, Dec. 2003, Nanjing, China
[55] C. W. Ting, W. H. Lam, and L. M. Po, "Fast block-Matching Motion Estimation by Recent-Biased Search for Multiple Reference Frames", Proceeding, of IEEE International Conference on Image Processing, pp. 1445-1448, Oct. 2004,Singapore.
[56] Hung-Ju Li, Ching-Ting Hsu and Mei-Juan Chen, "Fast multiple reference frame selection method for motion estimation in JVT-H.264", IEEE Asia-Pacific Conf.on Circuits and Systems (APCCAS-2004), Tainan, Taiwan, December 6-9, 2004.
[57] X. Li, E. Li, and Y.-K. Chen, "Fast multi-frame motion estimation algorithm with adaptive search strategies in H.264," IEEE International Conference on Acoustics,Speech, and Signal Processing (ICASSP2004) , vol. 3, pp. 369-372, May 2004.
[58] Shen,Y.F., Chao,H., Yu,L.J., Zhang,D.M., Li,J.T, "Fast multi-frame motion estimation algorithm in H.264", 2004 International Conference On Signal Processing (ICSP2004) , August 2004.
[59] F. Pan, X. Lin, R. Susanto, K. P. Lim, Z. G. Li, G. N. Feng, D. J. Wu, and S. Wu,"Fast Mode Decision for Intra Prediction," Doc. G013, Mar. 2003.
[60] K. P. Lim, S. Wu, D. J. Wu, S. Rahardja, X. Lin, F. Pan, Z. G. Li, "Fast INTER Mode Selection," Doc. 1020, Sep. 2003.
[61] J. Lee and B. Jeon, "Fast Mode Decision for H.264 with Variable Motion Block Sizes," International Symposium on Computer and Information Sciences (ISCIS),Nov. 2003.
[62] J. Lee and B. Jeon, "Pruned Mode Decision based on Variable Block Sizes Motion Compensation for H.264," Multimedia Interactive Protocols and Systems (MIPS), Nov. 2003.
[63] B. Jeon and J. Lee, "Fast Mode Decision for H.264," ISO/IEC JTC1/SC29/WG11 and ITU-T SG16 Q.6, JVT 10th Meeting, Waikoloa, Hawaii, December 2003.
[64] B. Meng, O. C. Au, C. W. Wong, and H. K. Lam, "Efficient Intra-Predction Mode Selection for 4×4 Blocks in H.264," IEEE Inter. Conf. on Multimedia and Expo,vol. 3, pp. 111-521-524, July 2003.
[65] P. Yin, H.-Y.C. Tourapis, A.M. Tourapis, and J. Boyce, "Fast mode decision and motion estimation for JVT/H.264," in Proceedings of International Conference on Image Processing, 2003, pp. 853-856.
[66] Y Zhao and I.E.G Richardson, "Computational Complexity Management of Motion Estimation in Video Encoders", IEEE Data Compression Conference, 2-4 April, 2002, Snowbird, UT, USA, pp. 483
[67] Zhi Yang, Hua Cai, and Jiang Li, "A Framework for Fine-granular Computational-complexity Scalable Motion Estimation", The 2005 IEEE International Symposium on Circuits and Systems (ISCAS2005), Kobe, Japan,23-26 May, 2005.
[68] X Yi, N Ling, "Scalable complexity-distortion model for fast motion estimation",Proceedings of the SPIE Conference on Visual Communications and Image Processing, Beijing, China, July 2005.
[69] Z. H. He, Y. F. Liang, L. L. Chen, I. Ahmad and D. P. Wu,"Power-Rate-Distortion Analysis for Wireless Video Communication Under Energy Constraints", IEEE Trans. on Circuits and Systems for Video Technology, vol. 15 , no.5 , pp.645-658, May. 2005.
[70] Y.-W Huang, C.-L Lee, C.-Y Chen, and L.-G. Chen, "One-Pass Computation-Aware Motion Estimation with. Adaptive Search Strategy", The 2005 IEEE International Symposium on Circuits and Systems (ISCAS2005),Kobe, Japan, 23-26 May, 2005.
[71] Pol Lin Tai, Shih-Yu Huang, Chii Tung Liu and Jia Shung Wang,"Computation-Aware Scheme for Software-based Block Motion Estimation," IEEE Transactions on Circuits and Systems for Video Technology, vol.35, pp.901-913, Sep,2003.
[72] M. Budagavi and J. Gibson, "Multi-frame Block Motion Compensated Video Coding for Wireless Channels," in Thirtieth Asilomar Conf. on Signals, Systems,and Computers, vol. 2, pp. 953-957, Nov. 1996.
[73] ITU-T Recommendation H.263, "Video Coding for Low Bitrate Communication," Annex N, 1997.
[74] T. Wiegand, X. Zhang, and B. Girod, "Block-Based Hybrid Video Coding Using Motion-Compensated Long-Term Memory Prediction," in Proc. of the Picture Coding Symposium, Berlin, Germany, pp. 153-158, Sept. 1997.
[75] ITU-T Recommendation H.263 "Video Coding for Low Bitrate Communication,"Annex U, 1999.
[76] Gary Sullivan, Thomas Wiegand and Keng-Pang Lim. Joint Model Reference Encoding Methods and Decoding Concealment Methods, Joint Video Team (JVT) of ISO/IEC MPEG and ITU-T VCEG, JVT-I049d0.doc, San Diego, USA,September, 2003
[77] G. Bjontegaard, "Calculation of Average PSNR Differences between RD-curves,"Doc. VCEG-M33, Apr. 2001.
[78] Y Zhao and I E G Richardson, "Macroblock Classification for Complexity Management of Video Encoders", Signal Processing: Image Communication, Vol.18, Issue 9, Oct. 2003 pp. 801-811.
[79] Y Zhao and I E G Richardson, "Macroblock skip-mode prediction for Complexity control of Video Encoders", Proc. IEE Visual Information Engineering, 7-9 July 2003, Surrey, U.K, pp. 5-8.
[80] Y Zhao and I E G Richardson, "Macroblock Classification for Video Encoder Complexity Management", Proc. International Picture Coding Symposium, 23-25 April 2003, Saint-Malo, France, pp. 371-376.
[81] Y Zhao and I E G Richardson, "Complexity Management for Video Encoders",Doctoral Symposium, ACM Multimedia Conference, 1-6 December 2002, Juan Les Pins, France, pp. 647-649.
[82] I E G Richardson and Y Zhao, "Adaptive Management of Video Encoder Complexity", Journal of Real-Time Imaging, Vol. 8, No. 4, Aug 2002, pp.291-301.
[83] I E G Richardson and Y Zhao, "Adaptive Algorithms for Variable Complexity Video Coding", Proc. International Conference on Image Processing (ICIP01),Thessaloniki, Greece, October 2001.
[84] Y Zhao and I E G Richardson, "Computational Complexity Management of Motion Estimation in Video Encoders", IEEE Data Compression Conference, 2-4 April, 2002, Snowbird, UT, USA, pp. 483.
[85] K. Lengwehasatit and A. Ortega, "Computationally scalable partial distance based fast search motion estimation," Proc. ICIP'2000, vol. 1, pp. 824-827, Sept.2000.
[86] Dongming Zhang, Chao Huang, et al.Complexity scalable motion estimation based on modes preselection in H.264.IEEE Int'l Conf on Signal Processing,Beijing, 2004.
[87] Kim, C; Xin, J.; Vetro, A.; Jay Kuo C.C., "Complexity Scalable Motion Estimation for H.264/AVC", SPIE Conference Visual Communications and Image Processing, Vol. 6077, pp. 109-120, January 2006.
[88]李宾,高平.H.264编码系统的特点及其应用前景[J].数字电视与数字视频No.6 2003.
[89]王嵩,薛全,张颖,陈建乐.H.264视频编码新标准及性能分析[J].数字电视与数字视频No.6.2003.
[90]M.Ravasi,M.Mattavelli and C.Clere.A computational complexity comparison of MPEG-4 and JVY codecs.Joint Video Team(JVT) of ISO/IEC MPEG &ITU-T VCEG,JVT-D153r1-L,July 2002.
[91]周敬利,余毅,余胜尘,郑俊浩.基于H.264视频编码技术的研究[J].华中科技大学学报(自然科学版)(J),2003,3l(8):32-34.
[92]薛全.H.264/AVC中运动估计、变换与解码器优化[D].浙江大学博士学位论文,浙江,2004年8月.
[93]刘海峰,郭主龙等.用于块匹配运动估值的正方形-菱形搜索算法[J].计算机学报,2002,25(7):747-752.
[94]田传艳,沈承东,李思昆.一种有效的基于上下文自适应搜索模式的快速运动估计算法.第13届全国多媒体技术学术会议(NCMT2004)论文集,P.291-292,2004.10,浙江 宁波.
[95]滕闽伟.H.264/AVC实时编码系统及其相关算法研究[D].上海大学博士论文,上海,2005年4月.
[96]裴世保,李厚强,俞能海.一种快速的H.264/AVC帧内预测模式选择算法[J].计算机工程与应用,2005年,第10期,pp.71-73.
[97]李军华,杜清秀.一种H.264的帧间宏块模式选择算法[J].科学技术与工程,2005年第18期,PP.1243-1247.
[98]余胜生,苏曙光,周敬利.基于H.26L多参考帧运动估计的研究及其新算法[J].计算机工程,2005年第6期,PP.176-178.
[99]滕国伟,张兆扬,张一钧,张文军.一种基于H.264/AVC的多参考帧快速选择算法[J].四川大学学报(工程科学版),2005年第4期,pp.100-103.
[100]http://www.ee.cityu.edu.hk/～lmpo/publications/20051105_ME_Programs.zip.
[101]K.R.Rao and J.J Hwang,Techniques and Standards for Image,Video and Audio Coding[M].Englewood Cliffs,N J:Prentice Hall,1996.
[102]李兴友,游志胜.一种新的基于运动矢量场及弹性模板的自适应快速搜索算法[J].计算机学报,第27卷第9期2004年9月.
[103]G.Sullivan,"Recommended Simulation Common Conditions for H.26L Coding Efficiency Experiments on Low-Resolution Progressive-Scan Source Material",document VCEG-N81,Sep.2001.
[104]J.Jain and A.Jain.Displacement measurement and its application in interframe image coding[J].IEEE Trans.Commun.,1981,29:1799-1808.
[105]M.Ghanbari.The cross-search algorithm for motion estimation[J].IEEE Trans.Commun.,1990,38:950-953.
[106]L.W.Lee,J.F.Wang,et al.Dynamic search-window adjustment and interlaced search for block-matching algorithm[J].IEEE Trans.Circuits Syst.Video Technol.,1993,3:85-87.
[107]田传艳.高效的视频压缩运动估计算法研究.国防科技大学硕士学位论文2004.12
[108]黎铁军.嵌入式流媒体处理器体系结构技术研究.国防科技大学博士学位论文.2005年9月.
[109]周恒.H.264的研究与软件实现[D].南京邮电学院硕士学位论文.2003年3月
[110]H.264 White paper UB Video Inc.www.ubvideo.com.
[111]SMPTE 421M,Draft SMPTE Standard for TV:VC-1 Compressed Video Bitstream Format and Decoding Process
[112]Srinivasan S.;(John) Hsu,P.;Holcomb,T.;Mukerjee,K.;Regunathan,S.L.;Lin,B.;Liang,J.;Lee,M.-C.;Ribas-Corbera,J.,"Windows Media Video 9:overview and applications",Signal Processing:Image Communication,Volume 19,Issue 9,1 October 2004,Pages 851-875.
[113]L.Fan,S.Ma,F.Wu:"Overview of AVS video standard",Proceedings of the ICME 2004:423-426.
[114]杨鹏.数字家电网络环境下的视频编码技术及系统实现[D].清华大学硕士学位论文,2004年6月.
[115]Yun Cheng,Zhiying Wang,Kui Dai and Jianjun Guo.A Fast Motion Estimation Algorithm Based on Diamond and Triangle Search Patterns.The 2nd Iberian Conference on Pattern Recognition and Image Analysis.June 7-9,2005.
[116]Yun Cheng,Kui Dai,Zhiying Wang and Jianjun Guo.A Fast Motion Estimation Algorithm Based on Diamond and Simplified Square Search Patterns.Progress in Pattern Recognition,Image Analysis and Applications:The 10th Iberoamerican Congress on Pattern Recognition.Nov.15-18,2005.
[117]Yun Cheng,Zhiying Wang,Jianjun Guo and Kui Dai.Research on Intra Modes for Inter-Frame Coding in H.264.Proc.Of the 9th International Conference on Computer Supported Cooperative Work in Design,May 24-26,2005.
[118]Mohammed E.Al-Mualla,Nishan Canagarajah and David R.Bull.Simplex.minimisation for multiple-reference motion estimation[C].ISCAS 2000,Vol Ⅳ,pp.Ⅳ-733-Ⅳ-736.
[119]Yu-Wen Huang,Bing-Yu Hsieh,et al.Analysis and reduction of reference frames for motion estimation in MPEG-4 AVC/JVT/H.264[C].ICASSP'03,Vol.3pp.Ⅲ- 145-Ⅲ- 148.
[120]Myung Jun Kim,Yun Gu Lee and Jong Beom RA.A fast multi-resolution block matching algorithm for multi-frame motion estimation[J].ICICE TRANS.INF.&SYST,Vol.E88-D,No.12,pp.2819-2827,Dec 2005.
[121]Changsung Kim,Hsuan-Huei Shih,et al..Multistage mode decision for intra prediction in H.264 codec[C].Proc.Of SPIE-IS&T Electronic Imaging,SPIE,5308
[122]Jongho Kim and Jechang Jeong.Fast intra-mode decision in H.264 video coding using simple directional masks.Visual Communications and Image Processing 2005,Proc of SPIE Vol.5960.pp.1071-1079