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A Stoppable Clock Based Four Step Search Block-Matching Motion Estimation Architecture 被引量:1
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作者 Salah Dhahri Abdelkrim Zitouni Kholdoun Torki 《Computer Technology and Application》 2011年第7期570-574,共5页
Motion Estimation (ME) is considerate one of the most important compression methods. However, ME involves high computational complexity. The main goal is to reduce power conception and the execution time without red... Motion Estimation (ME) is considerate one of the most important compression methods. However, ME involves high computational complexity. The main goal is to reduce power conception and the execution time without reducing image quality. In this paper, the authors have proposed high parallel processing architecture is presented for four-step search block-matching motion estimation. The proposed method is based on the stoppable clock models. The architecture has been simulated and synthesized with VHDL and ASIC (CMOS 45 nm). Synthesize results show that the proposed architecture reduces the power consumption and achieves a high performance for real time motion estimation. 展开更多
关键词 H264 four step search power consumption motion estimation.
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Video Image Block-matching Motion Estimation Algorithm Based on Two-step Search
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作者 金伟其 陈艳 +4 位作者 王岭雪 刘斌 刘崇亮 沈亚中 张桂清 《Journal of Measurement Science and Instrumentation》 CAS 2010年第3期228-232,共5页
Aiming at the shortcoming that certain existing blockingmatching algorithrns, such as full search, three-step search, and dia- mond search algorithms, usually can not keep a good balance between high acoaracy and low ... Aiming at the shortcoming that certain existing blockingmatching algorithrns, such as full search, three-step search, and dia- mond search algorithms, usually can not keep a good balance between high acoaracy and low computational complexity, a block-maching motion estimation algorithm based on two-step search is proposed in this paper. According to the fact that the gray values of adjacent pixels will not vary fast, the algorithm employs an interlaced search pattem in the search window to estimate the motion vector of the objectblock. Simulation and actual experiments demanstrate that the proposed algmithm greatly outperforms the well-known three-step search and dianond search algoritlam, no matter the motion vector is large or small. Comparedc with the full search algorithm, the proposed one achieves similar peffomance but requires much less computation, therefore, the algorithm is well qualified for real-time video image processing. 展开更多
关键词 block-matching rnation estimation two-step search
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Bioinspired Polarized Optical Flow Enables Turbid Underwater Target Motion Estimation
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作者 CHENG Haoyuan ZHAO Shujie +2 位作者 ZHU Jinchi YU Hao CHU Jinkui 《Journal of Ocean University of China》 SCIE CAS CSCD 2024年第4期915-923,共9页
Underwater target motion estimation is a challenge for ocean military and scientific research.In this work,we propose a method based on the combination of polarization imaging and optical flow for turbid underwater ta... Underwater target motion estimation is a challenge for ocean military and scientific research.In this work,we propose a method based on the combination of polarization imaging and optical flow for turbid underwater target detection.Polarization imaging can reduce the influence of backscattered light and obtain high-quality images underwater.The optical flow shows the motion and structural information of the target.We use polarized optical flow to obtain the optical flow field and estimate the target motion.The experimental results of different targets under varying water turbidity levels illustrate that our method is realizable and robust.The precision is verified by comparing the results with the precise displacement data and calculating two error measures.The proposed method based on polarized optical flow can obtain accurate displacement information and a good recognition effect.Moving target segmentation based on the Otsu method further proves the superiority of the polarized optical flow under turbid water.This study is valuable for target detection and motion estimation in scattering environments. 展开更多
关键词 turbid underwater motion estimation polarization imaging optical flow
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Nonparametric Estimation of the Trend Function for Stochastic Processes Driven by Fractional Brownian Motion of the Second Kind
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作者 WANG Yihan ZHANG Xuekang 《应用数学》 北大核心 2024年第4期885-892,共8页
The present paper deals with the problem of nonparametric kernel density estimation of the trend function for stochastic processes driven by fractional Brownian motion of the second kind.The consistency,the rate of co... The present paper deals with the problem of nonparametric kernel density estimation of the trend function for stochastic processes driven by fractional Brownian motion of the second kind.The consistency,the rate of convergence,and the asymptotic normality of the kernel-type estimator are discussed.Besides,we prove that the rate of convergence of the kernel-type estimator depends on the smoothness of the trend of the nonperturbed system. 展开更多
关键词 Nonparametric estimation Fractional Brownian motion Uniform consistency Asymptotic normality
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Efficient and Low-Latency Systolic Array Architecture for Full Searches in Block-Matching Motion Estimation
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作者 张武健 邱晓海 +1 位作者 周润德 陈弘毅 《Tsinghua Science and Technology》 SCIE EI CAS 2001年第4期361-368,共8页
This paper describes an efficient, low latency systolic array architecture for full searches in block matching motion estimation. Conventional one dimensional systolic array architecture is used to develop a nove... This paper describes an efficient, low latency systolic array architecture for full searches in block matching motion estimation. Conventional one dimensional systolic array architecture is used to develop a novel ring like systolic array architecture through operator rescheduling considering the symmetry of the data flow. High latency delay due to stuffing of the array pipeline in the conventional architecture was eliminated. The new architecture delivers a higher throughput rate, achieves higher processor utilization, and has low power consumption. In addition, the minimum memory bandwidth of the conventional architecture is preserved. 展开更多
关键词 motion estimation full search systolic array low latency low power
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Non-cooperative Space Target Estimation Algorithm Without Prior Information Dependence Based on Temporal Line of Sight Constraint
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作者 XIAO Hui ZHU Chongrui +3 位作者 LIU Xinqi YU Yifan SHENG Qinghong YANG Rui 《Transactions of Nanjing University of Aeronautics and Astronautics》 EI CSCD 2024年第4期526-540,共15页
Under single-satellite observation,the parameter estimation of the boost phase of high-precision space noncooperative targets requires prior information.To improve the accuracy without prior information,we propose a p... Under single-satellite observation,the parameter estimation of the boost phase of high-precision space noncooperative targets requires prior information.To improve the accuracy without prior information,we propose a parameter estimation model of the boost phase based on trajectory plane parametric cutting.The use of the plane passing through the geo-center and the cutting sequence line of sight(LOS)generates the trajectory-cutting plane.With the coefficient of the trajectory cutting plane directly used as the parameter to be estimated,a motion parameter estimation model in space non-cooperative targets is established,and the Gauss-Newton iteration method is used to solve the flight parameters.The experimental results show that the estimation algorithm proposed in this paper weakly relies on prior information and has higher estimation accuracy,providing a practical new idea and method for the parameter estimation of space non-cooperative targets under single-satellite warning. 展开更多
关键词 motion parameter estimation estimation of impact point infrared early warning boost phase modeling trajectory database construction
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Movement Function Assessment Based on Human Pose Estimation from Multi-View
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作者 Lingling Chen Tong Liu +1 位作者 Zhuo Gong Ding Wang 《Computer Systems Science & Engineering》 2024年第2期321-339,共19页
Human pose estimation is a basic and critical task in the field of computer vision that involves determining the position(or spatial coordinates)of the joints of the human body in a given image or video.It is widely u... Human pose estimation is a basic and critical task in the field of computer vision that involves determining the position(or spatial coordinates)of the joints of the human body in a given image or video.It is widely used in motion analysis,medical evaluation,and behavior monitoring.In this paper,the authors propose a method for multi-view human pose estimation.Two image sensors were placed orthogonally with respect to each other to capture the pose of the subject as they moved,and this yielded accurate and comprehensive results of three-dimensional(3D)motion reconstruction that helped capture their multi-directional poses.Following this,we propose a method based on 3D pose estimation to assess the similarity of the features of motion of patients with motor dysfunction by comparing differences between their range of motion and that of normal subjects.We converted these differences into Fugl–Meyer assessment(FMA)scores in order to quantify them.Finally,we implemented the proposed method in the Unity framework,and built a Virtual Reality platform that provides users with human–computer interaction to make the task more enjoyable for them and ensure their active participation in the assessment process.The goal is to provide a suitable means of assessing movement disorders without requiring the immediate supervision of a physician. 展开更多
关键词 Human pose estimation 3D pose reconstruction assessment of movement function plane of features of human motion
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Exploration on 2D DOA Estimation of Linear Array Motion:Uniform Linear Motion
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作者 Jianhong Chu Zhi Zhang Yu Guo 《China Communications》 SCIE CSCD 2023年第11期78-95,共18页
Generally,due to the limitation of the dimension of the array aperture,linear arrays cannot achieve two-dimensional(2D)direction of arrival(DOA)estimation.But the emergence of array motion provides a chance for that.I... Generally,due to the limitation of the dimension of the array aperture,linear arrays cannot achieve two-dimensional(2D)direction of arrival(DOA)estimation.But the emergence of array motion provides a chance for that.In this paper,a generalized motion scheme and a novel method of 2D DOA estimation are proposed by exploring the linear array motion.To be specific,the linear arrays are controlled to move along an arbitrary direction at a constant velocity and snap per fixed time delay.All the received signals are processed to synthesize the comprehensive observation vector for an extended 2D virtual aperture.Subsequently,since most of 2D DOA estimation methods are not universal to our proposed motion scheme and the reduced-dimensional(RD)method fails to handle the case of the coupled parameters,a decoupled reduced-complexity multiple signals classification(DRC MUSIC)algorithm is designed specifically.Simulation results demonstrate that:a)our proposed scheme can achieve underdetermined 2D DOA estimation just by the linear arrays;b)our designed DRC MUSIC algorithm has the good properties of high accuracy and low complexity;c)our proposed motion scheme with the DRC method has better universality in the motion direction. 展开更多
关键词 2D DOA estimation linear array motion reduced complexity synthetic aperture
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MOVING OBJECT TRACKING IN DYNAMIC IMAGE SEQUENCE BASED ON ESTIMATION OF MOTION VECTORS OF FEATURE POINTS 被引量:2
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作者 黎宁 周建江 张星星 《Transactions of Nanjing University of Aeronautics and Astronautics》 EI 2009年第4期295-300,共6页
An improved estimation of motion vectors of feature points is proposed for tracking moving objects of dynamic image sequence. Feature points are firstly extracted by the improved minimum intensity change (MIC) algor... An improved estimation of motion vectors of feature points is proposed for tracking moving objects of dynamic image sequence. Feature points are firstly extracted by the improved minimum intensity change (MIC) algorithm. The matching points of these feature points are then determined by adaptive rood pattern searching. Based on the random sample consensus (RANSAC) method, the background motion is finally compensated by the parameters of an affine transform of the background motion. With reasonable morphological filtering, the moving objects are completely extracted from the background, and then tracked accurately. Experimental results show that the improved method is successful on the motion background compensation and offers great promise in tracking moving objects of the dynamic image sequence. 展开更多
关键词 motion compensation motion estimation feature extraction moving object tracking dynamic image sequence
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Fast global motion estimation and moving object extraction algorithm in image sequences 被引量:2
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作者 张涛 费树岷 +1 位作者 李晓东 路红 《Journal of Southeast University(English Edition)》 EI CAS 2008年第2期192-196,共5页
A novel and effective approach to global motion estimation and moving object extraction is proposed. First, the translational motion model is used because of the fact that complex motion can be decomposed as a sum of ... A novel and effective approach to global motion estimation and moving object extraction is proposed. First, the translational motion model is used because of the fact that complex motion can be decomposed as a sum of translational components. Then in this application, the edge gray horizontal and vertical projections are used as the block matching feature for the motion vectors estimation. The proposed algorithm reduces the motion estimation computations by calculating the onedimensional vectors rather than the two-dimensional ones. Once the global motion is robustly estimated, relatively stationary background can be almost completely eliminated through the inter-frame difference method. To achieve an accurate object extraction result, the higher-order statistics (HOS) algorithm is used to discriminate backgrounds and moving objects. Experimental results validate that the proposed method is an effective way for global motion estimation and object extraction. 展开更多
关键词 global motion estimation edge projection higherorder statistics moving object extraction
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Intention Estimation of Adversarial Spatial Target Based on Fuzzy Inference 被引量:2
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作者 Wenjia Xiang Xiaoyu Li +4 位作者 Zirui He Chenjing Su Wangchi Cheng Chao Lu Shan Yang 《Intelligent Automation & Soft Computing》 SCIE 2023年第3期3627-3639,共13页
Estimating the intention of space objects plays an important role in air-craft design,aviation safety,military and otherfields,and is an important refer-ence basis for air situation analysis and command decision-making... Estimating the intention of space objects plays an important role in air-craft design,aviation safety,military and otherfields,and is an important refer-ence basis for air situation analysis and command decision-making.This paper studies an intention estimation method based on fuzzy theory,combining prob-ability to calculate the intention between two objects.This method takes a space object as the origin of coordinates,observes the target’s distance,speed,relative heading angle,altitude difference,steering trend and etc.,then introduces the spe-cific calculation methods of these parameters.Through calculation,values are input into the fuzzy inference model,andfinally the action intention of the target is obtained through the fuzzy rule table and historical weighted probability.Ver-ified by simulation experiment,the target intention inferred by this method is roughly the same as the actual behavior of the target,which proves that the meth-od for identifying the target intention is effective. 展开更多
关键词 Intension estimation motion parameters calculation fuzzy inference fuzzy rule table historical weighted probability
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6-DOF MOTION AND CENTER OF ROTATION ESTIMATION BASED ON STEREO VISION 被引量:8
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作者 CAO Wanpeng BI Wei +2 位作者 CHE Rensheng GUO Wenbo YE Dong 《Chinese Journal of Mechanical Engineering》 SCIE EI CAS CSCD 2008年第2期87-92,共6页
A new motion model and estimation algorithm is proposed to compute the general rigid motion object's 6-DOF motion parameters and center of rotation based on stereo vision. The object's 6-DOF motion model is designed... A new motion model and estimation algorithm is proposed to compute the general rigid motion object's 6-DOF motion parameters and center of rotation based on stereo vision. The object's 6-DOF motion model is designed from the rigid object's motion character under the two defined reference frames. According to the rigid object's motion model and motion dynamics knowledge, the corresponding motion algorithm to compute the 6-DOF motion parameters is worked out. By the rigid object pure rotation motion model and space sphere geometry knowledge, the center of rotation may be calculated after eliminating the translation motion out of the 6-DOF motion. The motion equations are educed based on the motion model and the closed-form solutions are figured out. To heighten the motion estimation algorithm's robust, RANSAC algorithm is applied to delete the outliers. Simulation and real experiments are conducted and the experiment results are analyzed. The results prove the motion model's correction and algorithm's validity. 展开更多
关键词 motion estimation Center of rotation 6-DOF motion Stereo vision
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Motion estimation in wide band synthetic aperture sonar based on the raw echo data using the method of displaced phase center antenna 被引量:3
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作者 JIANG Xiaokui, SUN Chao (Member, IEEE), FANG Jie (Institute of Acoustic Engineering, Northwestern Polytechnical University, Xi’an 710072, China) 《声学技术》 CSCD 2003年第z1期56-59,共4页
Phase errors in synthetic aperture sonar (SAS) imaging must be reduced to less than one eighth of a wavelength so as to avoid image destruction. Most of the phase errors occur as a result of platform motion errors, fo... Phase errors in synthetic aperture sonar (SAS) imaging must be reduced to less than one eighth of a wavelength so as to avoid image destruction. Most of the phase errors occur as a result of platform motion errors, for example, sway yaw and surge that are the most important error sources. The phase error of a wide band synthetic aperture sonar is modeled and solutions to sway yaw and surge motion estimation based on the raw sonar echo data with a Displaced Phase Center Antenna (DPCA) method are proposed and their implementations are detailed in this paper. It is shown that the sway estimates can be obtained from the correlation lag and phase difference between the returns at coincident phase centers. An estimate of yaw is also possible if such a technique is applied to more than one overlapping phase center positions. Surge estimates can be obtained by identifying pairs of phase centers with a maximum correlation coefficient. The method works only if the platform velocity is low enough such that a number of phase centers from adjacent pings overlap. 展开更多
关键词 sonar SYNTHETIC APERTURE SONAR (SAS) motion estimation RAW data DPCA.
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6-DOF motion estimation using optical flow based on dual cameras 被引量:3
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作者 刘梦瑶 王岩 郭雷 《Journal of Central South University》 SCIE EI CAS CSCD 2017年第2期459-466,共8页
Because of its characteristics of simple algorithm and hardware, optical flow-based motion estimation has become a hot research field, especially in GPS-denied environment. Optical flow could be used to obtain the air... Because of its characteristics of simple algorithm and hardware, optical flow-based motion estimation has become a hot research field, especially in GPS-denied environment. Optical flow could be used to obtain the aircraft motion information, but the six-(degree of freedom)(6-DOF) motion still couldn't be accurately estimated by existing methods. The purpose of this work is to provide a motion estimation method based on optical flow from forward and down looking cameras, which doesn't rely on the assumption of level flight. First, the distribution and decoupling method of optical flow from forward camera are utilized to get attitude. Then, the resulted angular velocities are utilized to obtain the translational optical flow of the down camera, which can eliminate the influence of rotational motion on velocity estimation. Besides, the translational motion estimation equation is simplified by establishing the relation between the depths of feature points and the aircraft altitude. Finally, simulation results show that the method presented is accurate and robust. 展开更多
关键词 optical flow motion estimation dual cameras six degree-of-freedom(6-DOF)
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LEAST SQUARES ESTIMATION FOR ORNSTEIN-UHLENBECK PROCESSES DRIVEN BY THE WEIGHTED FRACTIONAL BROWNIAN MOTION 被引量:3
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作者 申广君 尹修伟 闫理坦 《Acta Mathematica Scientia》 SCIE CSCD 2016年第2期394-408,共15页
In this article, we study a least squares estimator (LSE) of θ for the Ornstein- Uhlenbeck process X0=0,dXt=θXtdt+dBt^ab, t ≥ 0 driven by weighted fractional Brownian motion B^a,b with parameters a, b. We obtain... In this article, we study a least squares estimator (LSE) of θ for the Ornstein- Uhlenbeck process X0=0,dXt=θXtdt+dBt^ab, t ≥ 0 driven by weighted fractional Brownian motion B^a,b with parameters a, b. We obtain the consistency and the asymptotic distribution of the LSE based on the observation {Xs, s∈[0,t]} as t tends to infinity. 展开更多
关键词 Weighted fractional Brownian motion least squares estimator Ornstein-Uhl-enbeck process
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A fast motion estimation algorithm for mobile communications 被引量:1
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作者 CHEN Guo-bin 《Journal of Zhejiang University-Science A(Applied Physics & Engineering)》 SCIE EI CAS CSCD 2006年第z1期13-18,共6页
The limitation of processing power, battery life and memory capacity of portable terminals requires reducing encoding complexity in mobile communications. Motion estimation (ME) is the most computationally intensive m... The limitation of processing power, battery life and memory capacity of portable terminals requires reducing encoding complexity in mobile communications. Motion estimation (ME) is the most computationally intensive module in a typical video codec, which determines not only the encoder's performance but also the reconstructed video quality. In this paper, a fast ME algorithm for H.264/AVC baseline profile coding is proposed based on the analysis of motion vector field and error surface, and the statistical distributions of different type macroblocks (MBs). Simulation results showed that: in comparison with MVFAST,the proposed algorithm can decrease the computational load over 7.2% with no requirement of expanding memory capacity while maintaining the same video quality as MVFAST. Furthermore, its simplicity makes it easy to be implemented on hardware. 展开更多
关键词 motion estimation (ME) ERROR surface motion VECTOR (MV)
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MULTI-RESOLUTION MOTION ESTIMATION AND COMPENSATION BASED ON ADJACENT PREDICTION OF FRAME DIFFERENCE IN WAVELET DOMAIN 被引量:3
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作者 Tang Guowei Gu Guochang 《Journal of Electronics(China)》 2009年第3期412-416,共5页
Aiming at the higher bit-rate occupation of motion vector encoding and more time load of full-searching strategies, a multi-resolution motion estimation and compensation algorithm based on adjacent prediction of frame... Aiming at the higher bit-rate occupation of motion vector encoding and more time load of full-searching strategies, a multi-resolution motion estimation and compensation algorithm based on adjacent prediction of frame difference was proposed.Differential motion detection was employed to image sequences and proper threshold was adopted to identify the connected region.Then the motion region was extracted to carry out motion estimation and motion compensation on it.The experiment results show that the encoding efficiency of motion vector is promoted, the complexity of motion estimation is reduced and the quality of the reconstruction image at the same bit-rate as Multi-Resolution Motion Estimation(MRME) is improved. 展开更多
关键词 Wavelet transforms motion estimation motion compensation Multi-resolution analysis Video coding
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Fast motion estimation algorithm for H.264/AVC based on centered prediction 被引量:1
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作者 Wei Zhou Zhemin Duan Hongqi Hu 《Journal of Systems Engineering and Electronics》 SCIE EI CSCD 2010年第6期1103-1110,共8页
H.264/AVC video coding standard can achieve roughly half of the bit-savings over MPEG2 and MPEG4 for a given quality. However, this comes at a cost in considerably increased complexity at the encoder and thus increase... H.264/AVC video coding standard can achieve roughly half of the bit-savings over MPEG2 and MPEG4 for a given quality. However, this comes at a cost in considerably increased complexity at the encoder and thus increases the difficulty in hardware implementation. The high redundancy that exists between the successive frames of a video sequence makes it possible to achieve a high data compression ratio. Motion estimation (ME) plays an important role in motion compensated video coding. A fast motion estimation algorithm for H.264/AVC is proposed based on centered prediction, called centered prediction based fast mixed search algorithm (CPFMS). It makes use of the spatial and temporal correlation in motion vector (MV) fields and feature of all-zero blocks to accelerate the searching process. With the initialized searching point prediction, adaptive search window changing and searching direction decision, CPFMS is provided to reduce computation in block-matching process. The experimental results show that the speed of CPFMS is nearly 12 times of FS with a negligible peak signal-noise ratio (PSNR) loss. Also, the efficiency of CPFMS outperforms some popular fast algorithms such as hybrid unsymmetrical cross multi-hexagongrid search and a novel multidirectional gradient descent search evidently. 展开更多
关键词 H.264/AVC motion estimation motion vectors early termination.
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A Correlation Tracking Algorithm Based on Template Partition Motion Estimation 被引量:1
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作者 徐一鸣 刘晓利 刘怡昕 《Defence Technology(防务技术)》 SCIE EI CAS 2009年第4期310-316,共7页
A correlation tracking algorithm based on template partition motion estimation proposed for improving real time performance of the conventional correlation matching algorithms. The target trajectory fitted using the l... A correlation tracking algorithm based on template partition motion estimation proposed for improving real time performance of the conventional correlation matching algorithms. The target trajectory fitted using the least square with equal space in whole interval and the target prediction point is found out. According to the requirements of block motion estimation(BME) algorithm,the template divided into some macro blocks. The searching process is conducted by using diamond search algorithm around the prediction point and the optimal motion vector of each block is calculated. A point corresponding to the motion vector with the best matching is taken as a rough matching point of the template. The relation of relative position between the block with matching point and the searching area determined to decide whether to conduct precise matching search or to construct a new search area in the gradient direction. The target tracking experiment results show that over 70% time cost can be reduced caompared with the conventional correlation matching algorithm based on full search method. 展开更多
关键词 computer application correlation matching target trajectory prediction block motion estimation diamond search
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A novel adjustable multiple cross-hexagonal search algorithm for fast block motion estimation 被引量:2
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作者 XIE Chun-lai CHEUNG Chun-ho LIU Wei-zhong 《Journal of Zhejiang University-Science A(Applied Physics & Engineering)》 SCIE EI CAS CSCD 2007年第8期1304-1310,共7页
In this paper,we propose a novel adjustable multiple cross-hexagonal search(AMCHS) algorithm for fast block motion estimation. It employs adjustable multiple cross search patterns(AMCSP) in the first step and then use... In this paper,we propose a novel adjustable multiple cross-hexagonal search(AMCHS) algorithm for fast block motion estimation. It employs adjustable multiple cross search patterns(AMCSP) in the first step and then uses half-way-skip and half-way-stop technique to determine whether to employ two hexagonal search patterns(HSPs) subsequently. The AMCSP can be used to find small motion vectors efficiently while the HSPs can be used to find large ones accurately to ensure prediction quality. Simulation results showed that our proposed AMCHS achieves faster search speed,and provides better distortion performance than other popular fast search algorithms,such as CDS and CDHS. 展开更多
关键词 motion estimation Fast search algorithm Adjustable search patterns Threshold strategy Hexagonal search pattern
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