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1.
The estimation of the velocity of objects imaged by television cameras is useful in different areas of image processing.The problem is solved by means of a linear estimation algorithm and the effects of noise superimposed to the signal are analyzed. The structure of a real-time estimator is then presented. Experimental results show that a very fine accuracy is obtained. They encourage its application to image coding for redundancy reduction using movement compensation.  相似文献   

2.
An iterative method for accurate movement estimation of television signals is analyzed. The method considered is based on an iterative process applied to the conventional gradient method. It is known that the gradient method has some problems both in its stability and in its accuracy for movements larger than 2 or 3 pel/frame. It is shown that when an iterative process is used, the estimated movement converges to the actual movement rapidly and is exponentially stable. It is also shown that the asymptotic accuracy of the iterative estimate is determined by the smoothness of the gradient and by the amount of the frame-to-frame noise. Some experimental results are given and compared to the theoretical result  相似文献   

3.
余越  周健 《电视技术》1998,(12):2-5
在分析了块匹配运动估值模型的基础上,指同处于块中央的象素眯在块匹配时作用 小,最了一种减少块匹配运算象素的方法。不仅如此,提出的方法可与任一基于减少匹配次数的快速算法相结合,从而得到各种事型的块匹配快速算法。最后试验结果,提出了的方法是有效的。  相似文献   

4.
车道线识别是安全辅助驾驶和智能驾驶系统的核心研究内容,对控制危险驾驶和疲劳驾驶均有显著的作用,通常利用Hough变换对直线检测的容错性和鲁棒性,可以对车载摄像头拍摄到的车道线进行有效的检出.巧妙地将分块Hough变换和图像块的运动估计相结合,极大地降低了车道线检测和跟踪的算法复杂度,实现了车道线的实时识别与跟踪.实验表明,采用该方法既可以得到稳定的检测结果,又能提高检测的速度,保留了Hough变换的容错性和鲁棒性.  相似文献   

5.
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 es timation is reduced and the quality of the reconstruction image at the same bit-rate as Multi-Reso lution Motion Estimation (MRME) is improved.  相似文献   

6.
文章介绍了一种一维光学相关器,在其傅里叶平面内,将液晶电视( L C T V) 编码成单极二元纯位相滤波器用于图像实时编码或解码。给出了初步光学实验结果  相似文献   

7.
This paper gives a simple analysis of the method of using the Hopfield's optimization neural network to solve the direction-of-arrival(DOA) estimation problem. Although this method can avoid the eigendecomposition of data autocorrelation matrix and the orthogonality search of parameter space, theoretical analysis and computer simulation results show that the construction of the DOA cost function is incorrect on the condition that there is no constraint on the number of outputs of the network.  相似文献   

8.
Video super-resolution (SR) is a process for reconstructing high-resolution (HR) images by utilizing complementary information among multiple low-resolution (LR) images. Accurate estimation of the motion among the LR images significantly affects the quality of the reconstructed HR image. In this paper, we analyze the possible reasons for the inaccuracy of motion estimation and then propose a multi-lateral filter to regularize the process of motion estimation. This filter can adaptively correct motion estimation according to the estimation reliability, image intensity discontinuity, and motion dissimilarity. Furthermore, we introduce a non-local prior to solve the ill-posed problem of HR image reconstruction. This prior can fully utilize the self-similarities existing in natural images to regularize the HR image reconstruction. Finally, we employ a Bayesian formulation to incorporate the two regularizations into one Maximum a Posteriori (MAP) estimation model, where the HR image and the motion estimation can be refined progressively in an alternative and iterative manner. In addition, an algorithm that estimates the blur kernel by analyzing edges in an image is also presented in this paper. Experimental results demonstrate that the proposed approaches are highly effective and compare favorably to state-of-the-art SR algorithms.  相似文献   

9.
In this paper, a Modified Complex Lapped Transform domain Motion Estimation (MCLT-ME) method to estimate the motion of video sequence is proposed. The proposed method is based on phase correlation of current window region and corresponding window region, and provides a significant improvement in motion estimation.  相似文献   

10.
运动估计是MPEG图像编码中提高压缩率最有效的方法,也是运算量最大的部分,因而也是较难实时实现的。针对“高清晰度电视功能样机”信源编码的要求,就全局运动做主方法提出了相应的硬件设计,并且完成了其硬件实现。  相似文献   

11.
Several specific features have been incorporated into Motion estimation (ME) in H.264 coding standard to improve its coding efficiency. However, they result in very high computational load. In this paper, a fast ME algorithm is proposed to reduce the computational complexity. First, a mode discriminant method is used to free the encoder from checking the small block size modes in homogeneous regions. Second, a condensed hierarchical block matching method and a spatial neighbor searching scheme are employed to find the best full-pixel motion vector. Finally, direction-based selection rule is utilized to reduce the searching range in sub-pixel ME process. Experimental results on commonly used QCIF and CIF format test sequences have shown that the proposed algorithm achieves a reduction of 88% ME process time on average, while incurring only 0.033 dB loss in PSNR and 0.50% increment on the total bit rate compared with that of exhaustive ME process, which is a default approach adopted in the JM reference software.  相似文献   

12.
In the Advanced Video Coding (AVC) standard, motion estimation (ME) adopts many new features to increase the coding performances such as block matching algorithm (BMA), motion vector prediction (MVP) and variable block size motion estimation (VBSME). However, VBSME is utilized in the MPEG4-AVC/H.264 standard which leads to high computational complexity and data dependency that make the hardware implementation very complex.  相似文献   

13.
Block matching has been used for motion estimation and motion compensation in the Audio and Video Standard (AVS) for years. While having an acceptable performance in describing motion between frames, it requires quite a few bits to represent the motion vectors. In certain circumstances, the use of global motion estimation and compensation would perform equally well or even better than the block matching in terms of motion accuracy, while it results in the coding of global motion model parameters. In this letter, we modify an AVS coder by adding (1) six global motion model parameters to the frame header, and (2) mode selection among INTRA, SKIP, INTER-16×16, INTER-16×8, INTER-8×16, INTER-8×8, and Global Motion Compensation (GMC) modes by Lagrange optimal rate-distortion criteria. Simulation results demonstrate that over 0.1dB improvement in PSNR is obtained compared to the AVS coder for an average coded P-frame with the same bitrate.  相似文献   

14.
激光电视的研究进展及趋势分析   总被引:1,自引:0,他引:1  
在显示技术日益重要的今天,激光电视以其他技术无法比拟的优势受到各国的关注.本文介绍了激光电视的基本概念和特点,从激光电视机的发展历史入手,主要介绍了代表世界先进水平的美、日、德三国的激光电视的发展现状,国内激光电视及相关技术的发展情况.总结出我国激光电视今后的发展目标--产业化.  相似文献   

15.
Motion-compensated filtering of time-varying images   总被引:1,自引:0,他引:1  
This paper presents the theory of motion-compensated spatiotemporal filtering of time-varying imagery. The properties of motion trajectories and their relation to displacement fields and velocity fields are presented. The constraints that image motion places on the time-varying image in both the spatiotemporal domain and in the frequency domain are described, along with the implications of these results on motion-compensated filtering and on sampling. An iterative method for estimating motion which generalizes many pixel-oriented and block-oriented methods is presented. Motion-compensated filtering is then applied to the problems of prediction, interpolation, and smoothing.Invited Paper  相似文献   

16.
大屏幕投影电视墙广泛应用在各种需要大显示画面的场合,本文较详细地论述了用投影电视改装电视墙的可能性和改装时要考虑的主要问题以及改装方法。  相似文献   

17.
In the video coding standards MPEG-x and H.26x, a motion-compensated prediction technique is used for enhancing the coding performance of bitrate reduction or peak signal to noise ratio (PSNR) improvement. This technique takes advantage of the correlation between consecutive frames in the time domain, which is relatively higher than that between adjacent blocks in the spatial domain. In order to utilize the correlation between consecutive frames, the conventional video coding standards have used the motion estimation (ME) and compensation technique, where the Sum of the Absolute Differences (SAD) is usually used as the distortion measure. The ME estimates the reference block that could minimize the residual signal between the current and reference blocks. However, the SAD is not appropriate to the specific sequences that have global or local illumination changes. In addition, the high-resolution video sequences have higher spatial correlation than the low-resolution video sequences in general. Therefore, a new distortion measure that can consider spatial and temporal correlation simultaneously may be helpful to enhance the coding performance. The proposed distortion measure searches for a reference block that minimizes the motion-compensated residual signal when the DC-component is predicted. In our proposed algorithm, the maximum BD-rate improvement is up to 13.6% for illumination-changed video sequences, and the average BD-rate improvement is 6.6% for various high-resolution video sequences in the baseline profile.  相似文献   

18.
This paper first presents an array structure using ±1 full-search (FS) architecture as the search engine of block motion estimation which takes advantage of the design regularity of FS. An efficient algorithm named modified gradient-descent search (MGDS) is then introduced based on the proposed architecture. MGDS utilizes an adaptive computation distribution mechanism to efficiently allocate computation of the employed ±1 FS array to blocks or frames of video sequences. Experimental results indicate that MGDS uniformly achieves a higher quality than FS by an amount that is dependent on motion activities of sequences.  相似文献   

19.
随着社会经济的发展,人们对广播电视节目的播出质量也有了更高的要求。在实践操作中,广播电视信号的安全性对于电视节目的安全播出具有重要意义。文章阐述无线发射技术在广播电视中的应用优势,探讨基于无线发射技术广播电视信号的安全性策略,以期提高信号传输发射整个流程的安全性,保证电视节目安全播出。  相似文献   

20.
该文提出了一种用于MPEG-4形状编码的快速运动估计算法。该算法利用了形状编码及形状信息的固有特性,即基于上下文的运动估计特性、相邻二值alpha块的运动矢量相关性以及形状信息的二值特性。模拟结果表明,该算法具有运算量少、处理速度快的特点,适用于MPEG-4形状编码的实时软件实现。  相似文献   

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