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Research on variable block size motion estimation algorithm for airborne image

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High Technology Letters 2014年第3期20卷 321-327页

作者：王科 Huang Dongshan Ma Li Zhang Yudong China National Aeronautical Electronic Radio Research Institute School of Electronic Information and Electrical EngineeringShanghai Jiaotong University

A fast motion estimation algorithm for variable block-size using the ＂line scan and block merge procedure＂ is proposed for airborne image compression *** hardware implementation via FPGA is discussed in *** proposed pipelined architecture based on the line scan algorithm is capable of calculating the required 41 motion vectors of various size blocks supported by H.264 within a 16 × 16 block in *** adaptive rate distortion cost function is used for various size block *** motion vectors of adjacent small blocks are merged to predict the motion vectors of larger blocks for reducing *** results show that our proposed method has lower computational complexity than full search algorithm with slight quality decrease and little bit rate *** to the high real-time processing speed it can be easily realized in hardware.

关键词： H.264 motion estimation line scan algorithm rate distortion optimization (RDO) FPGA block merge method

Fast Approaches for Sub-pixel Precision Variable Block Size motion estimation

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Journal of Beijing Institute of Technology 2009年第2期18卷 209-214页

作者：张颖萧允治沈庭芝 School of Information and Electronics Beijing Institute of Technology Department of Electronic and Information Engineering The Hong Kong Polytechnic UniversityHung HomKowloon

The new features of H. 264 video coding standard make the motion estimation module much more time consuming than before. Especially, the motion search is required for each of the 4 modes for inter prediction. In order to reduce the computational complexity, we analyze the statistics of results of motion estimation, such as the continuity of best modes of blocks in successive frames and the chance to give up a sub-partition mode （smaller than 16 × 16） after integer-pixel motion estimation, from which we suggest to make mode prediction based on the motion information of the previous frame and skip sub-pixel motion estimation in subpartition mode selectively. According to the experimental result, the proposed algorithm can save 75 % of the computational time with a slight degradation （0.03 dB） on PSNR compared with the pseudocode of fast search motion estimation in JM12.2.

关键词： video coding motion estimation sub-pixel variable block size

Advanced 4-dimensional cone-beam computed tomography reconstruction by combining motion estimation, motioncompensated reconstruction, biomechanical modeling and deep learning

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Visual Computing for Industry,Biomedicine,and Art 2019年第1期2卷 221-235页

作者： You Zhang Xiaokun Huang Jing Wang Division of Medical Physics and Engineering Department of Radiation OncologyUT Southwestern Medical Center2280 Inwood RoadDallasTX 75390USA

4-Dimensional cone-beam computed tomography(4D-CBCT)offers several key advantages over conventional 3DCBCT in moving target localization/delineation,structure de-blurring,target motion tracking,treatment dose accumulation and adaptive radiation ***,the use of the 4D-CBCT in current radiation therapy practices has been limited,mostly due to its sub-optimal image quality from limited angular sampling of conebeam *** this study,we summarized the recent developments of 4D-CBCT reconstruction techniques for image quality improvement,and introduced our developments of a new 4D-CBCT reconstruction technique which features simultaneous motion estimation and image reconstruction(SMEIR).Based on the original SMEIR scheme,biomechanical modeling-guided SMEIR(SMEIR-Bio)was introduced to further improve the reconstruction accuracy of fine details in lung *** improve the efficiency of reconstruction,we recently developed a U-net-based deformation-vector-field(DVF)optimization technique to leverage a population-based deep learning scheme to improve the accuracy of intra-lung DVFs(SMEIR-Unet),without explicit biomechanical *** of each of the SMEIR,SMEIR-Bio and SMEIR-Unet techniques were included in this study,along with the corresponding results comparing the reconstruction accuracy in terms of CBCT images and the *** also discussed the application prospects of the SMEIR-type techniques in image-guided radiation therapy and adaptive radiation therapy,and presented potential schemes on future developments to achieve faster and more accurate 4D-CBCT imaging.

关键词： Cone-beam computed tomography Image reconstruction motion estimation Biomechanical modeling Deep learning

Time-frequency characteristics based motion estimation and imaging for high speed spinning targets via narrowband waveforms

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Science China(Information Sciences) 2010年第8期53卷 1628-1640页

作者： ZHANG Lei , LI YaChao, LIU Yan, XING MengDao & BAO Zheng National Lab for Radar Signal Processing, Xidian University, Xi’an 710071, China 1. National Lab for Radar Signal Processing Xidian University Xi’an 710071 China

This paper focuses on the motion parameters estimation and inversed synthetic aperture radar (ISAR) imaging for the high-speed spinning targets via the time-frequency characteristics. Assuming that the translational motion is compensated with the available motion compensation techniques, then the residual part of translational motion and the spinning motion are estimated with high precision based on the timefrequency characteristics. Combining with the procedure of the motion estimation, a novel coherent timefrequency spectrum intensity redistribution method, coherent single range Doppler interferometry (CSRDI), is proposed, which provides higher resolution and sustain lower signal to noise rate (SNR) than the current approach. Numerical simulation confirms the validity and high precision of the proposed approaches.

关键词： ISAR time-frequency characteristics CSRDI motion estimation high speed spinning targets

Fast motion estimation algorithm of video stabilization system

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Journal of Beijing Institute of Technology 2014年第1期23卷 102-107页

作者： WU Hao DENG Hong-bin School of Information and Electronics Beijing Institute of Technology Beijing 100081 China School of Mechatronical Engineering Beijing Institute of Technology Beijing 100081 China

A real-time electronic image stabilization motion estimation method based on fast sub- block gray projection algorithm is proposed. In the method, each image is divided into a number of sub-blocks, and sub-blocks are sifted with their gray gradients. After removing sub-blocks whose gray gradients are lower than the given threshold, the calculation amount of projection is reduced and the motion estimation accuracy is improved. Then gray projection is done in each remained sub- block, and global motion vector of the image is calculated according to the local motion vectors of sub-blocks and the affine motion model. The drawbacks as the local motions reducing the global mo- tion estimation accuracy and traditional gray projection algorithm could not deal with rotation are re- solved well by this algorithm. The experiment results show that the algorithm is more accurate and efficient than the gray projection algorithm.

关键词： video stabilization motion estimation gray projection algorithm gray gradient

Wavelets and Optical Flow motion estimation

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Numerical Mathematics(Theory,Methods and Applications) 2013年第1期6卷 116-137页

作者： P.Dérian P.Héas C.Herzet E.Mémin Departments of Physics and Geosciences California State University ChicoChicoCA 95929-0555USA INRIA Rennes-Bretagne Atlantique Campus de Beaulieu35042 Rennes CEDEXFrance

This article describes the implementation of a simple wavelet-based optical-flow motion estimator dedicated to continuous motions such as fluid flows. The waveletrepresentation of the unknown velocity field is considered. This scale-space representation, associated to a simple gradient-based optimization algorithm, sets up a welldefined multiresolution framework for the optical flow estimation. Moreover, a verysimple closure mechanism, approaching locally the solution by high-order polynomialsis provided by truncating the wavelet basis at fine scales. Accuracy and efficiency of theproposed method is evaluated on image sequences of turbulent fluid flows.

关键词： Wavelets optical flow motion estimation large displacements fluid flows

Sub-pixel motion estimation using phase correlation: comparisons and evaluations

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International Journal of Intelligent Computing and Cybernetics 2016年第4期9卷 394-405页

作者： Jie Ren Huimin Zhao Jinchang Ren Shi Cheng College of Electronics and Information Xi’an Polytechnic UniversityXi’anChina School of Electronic and Information Engineering Guangdong Polytechnic Normal UniversityGuangzhouChina Department of Electronic and Electrical Engineering University of StrathclydeGlasgowUK School of Computer Science Shaanxi Normal UniversityXi’anChina

Purpose-Effective and robust motion estimation with sub-pixel accuracy is essential in many image processing and computer vision *** to its computational efficiency and robustness in the presence of intensity changes as well as geometric distortions,phase correlation in the Fourier domain provides an attractive solution for global motion estimation and image *** paper aims to discuss these ***/methodology/approach-In this paper,relevant sub-pixel strategies are categorized into three classes,namely,single-side peak interpolation,dual-side peak interpolation and curve *** well-known images“Barbara”and“Pentagon”were used to evaluate the performance of eight typical methods,in which Gaussian noise was attached in the synthetic ***-For eight such typical methods,the tests using synthetic data have suggested that considering dual-side peaks in interpolation or fitting helps to produce better *** addition,dual-side interpolation outperforms curve fitting methods in dealing with noisy ***,Gaussian-based dual-side interpolation seems the best in the ***/value-Based on the comparisons of eight typical methods,the authors can have a better understanding of the phase correlation for motion *** evaluation can provide useful guidance in this context.

关键词： Linear interpolation motion estimation Phase correlation Sub-pixel registration

An Object-Based Fast motion estimation Algorithm in MPEG-4

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Journal of Shanghai Jiaotong university(Science) 2006年第3期11卷 340-345页

作者：孙雷张文军余松煜刘勋 Inst.of Image Communication & Information Processing Shanghai Jiaotong Univ. Shanghai 200030China

This paper presented an object-based fast motion estimation (ME) algorithm for object-based texture coding in moving picture experts group four (MPEG-4), which takes full advantage of the shape information of video object. Compared with the full search (FS) algorithm, the proposed algorithm can significantly speed the ME process. The speed of ME using the proposed algorithm is faster than that using new three-step search (NTSS), four-step search (4SS), diamond search (DS), and block-based gradient descent search (BBGDS) algorithms with similar motion compensation (MC) errors. The proposed algorithm can be combined with other fast ME algorithm to make the ME process faster.

关键词： MPEG 4 motion estimation video object

Fast Sub-Pixel motion estimation Algorithm For H.264

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Transactions of Tianjin University 2007年第4期13卷 286-290页

作者：李华胡浩高伟 School of Electronic Information Engineering Tianjin University

A novel fast sub-pixel search algorithm is proposed to accelerate sub-pixel search. Based on the features of predicted motion vector (PMV) and texture direction observed, the proposed method effectively filters out impossible points and thus decreases 11 searched points in average during the sub-pixel search stage. A threshold is also adopted to early terminate the sub-pixel search. Simulation results show that the proposed method can achieve up to 4.8 times faster than full sub-pixel motion search scheme (FSPS) with less than 0.025 dB PSNR losses and 2.2% bit-length increases.

关键词： H.264 motion estimation sub-pixel predicted motion vector texture characteristic