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961.
Aditya RamamoorthyAuthor Vitae Subhashis BanerjeeAuthor Vitae 《Pattern recognition》2003,36(9):2069-2081
This paper is concerned with the problem of recognition of dynamic hand gestures. We have considered gestures which are sequences of distinct hand poses. In these gestures hand poses can undergo motion and discrete changes. However, continuous deformations of the hand shapes are not permitted. We have developed a recognition engine which can reliably recognize these gestures despite individual variations. The engine also has the ability to detect start and end of gesture sequences in an automated fashion. The recognition strategy uses a combination of static shape recognition (performed using contour discriminant analysis), Kalman filter based hand tracking and a HMM based temporal characterization scheme. The system is fairly robust to background clutter and uses skin color for static shape recognition and tracking. A real time implementation on standard hardware is developed. Experimental results establish the effectiveness of the approach. 相似文献
962.
基于形态图表示的三维物体识别的基本思路是:首先建立待识别物体的模型库,找出模型集中所有模型物体的形态图和特征视图,并提取以它们的拓扑结构信息和几何信息;其次对物体真实图像作轮廓提取和0边界跟踪,得到二维图像的线架图,同时提取出它的拓扑结构信息和几何信息;最后将物体图像的拓扑结构信息和几何信息与模型库中模型物体的拓扑结构信息和几何信息匹配,从而达到识别的目的。文中提出了在生成线图链码时提取其拓扑结构信息和几何信息的方法,由拓扑结构信息和几何信息构造特征矩阵的方法,以及识别过程中特征矩阵的匹配算法。 相似文献
963.
为了简化融合中心数据处理的复杂度,减轻计算机的负担和通信开销,研究了两传感器两采样周期的数据关联问题。建立了测量到航迹分配的线性规划数学模型,提出了关联测量数据的融合方法,采用带滤波器的遗传算法求解最优分配方案。仿真结果表明,这种数据关联方法所得到的目标航迹比单传感器的目标航迹更加精确。 相似文献
964.
自校正与自适应组合结构的动态跟踪控制 总被引:1,自引:0,他引:1
当速度随负荷波动而随机变化时,为保证柴油机调速稳定而采取的传统控制算法,控制效果较差。给出了柴油机速度控制的一种有效方法。在柴油机调速过程中采用双闭环的控制结构,通过在外环采用自校正控制来调整速度参数的变化;在内环则采用自适应控制来跟踪齿条位移的变化并实时控制。最后将自校正控制与自适应控制有效组合。完成了柴油机速度控制的优越算法,实现了对有关参数的动态跟踪,并保证了输出速度的稳定。仿真结果和实际应用证明,所给的控制算法是有效的。 相似文献
965.
966.
Real-time three-dimensional tracking of people is an important requirement for a growing number of applications. In this
paper we describe two trackers; both of them use a network of video cameras for person tracking. These trackers are called
a rectilinear video array tracker (R-VAT) and an omnidirectional video array tracker (O-VAT), indicating the two different
ways of video capture. The specific objectives of this paper are twofold: (i) to present a systematic comparison of these
two trackers using an extensive series of experiments conducted in an `intelligent' room; (ii) to develop a real-time system
for tracking the head and face of a person, as an extension of the O-VAT approach. The comparative research indicates that
O-VAT is more robust to the number of people, less complex and runs faster, needs manual camera calibration, and the integrated
omnidirectional video network has better reconfigurability. The person head and face tracker study shows that such a system
can serve as a most effective input stage for face recognition and facial expression analysis modules. 相似文献
967.
Zaritsky Reuven Peterfreund Natan Shimkin Nahum 《International Journal of Computer Vision》2003,51(3):219-238
This paper presents a 3D active contour model for boundary detection and tracking of non-rigid objects, which applies stereo vision and motion analysis to the class of energy-minimizing deformable contour models, known as snakes. The proposed contour evolves in three-dimensional space in reaction to a 3D potential function, which is derived by projecting the contour onto the 2D stereo images. The potential function is augmented by a kinetic term, which is related to the velocity field along the contour. This term is used to guide the inter-image contour displacement. The incorporation of inter-frame velocity estimates in the tracking algorithm is especially important for contours which evolve in 3D space, where the added freedom of motion can easily result in loss of tracking. The proposed scheme incorporates local velocity information seamlessly in the snake model, with little computational overhead, and does not require exogenous computation of the optical flow or related quantities in each image. The resulting algorithm is shown to provide good tracking performance with only one iteration per frame, which provides a considerable advantage for real time operation. 相似文献
968.
M2Tracker: A Multi-View Approach to Segmenting and Tracking People in a Cluttered Scene 总被引:1,自引:0,他引:1
When occlusion is minimal, a single camera is generally sufficient to detect and track objects. However, when the density of objects is high, the resulting occlusion and lack of visibility suggests the use of multiple cameras and collaboration between them so that an object is detected using information available from all the cameras in the scene.In this paper, we present a system that is capable of segmenting, detecting and tracking multiple people in a cluttered scene using multiple synchronized surveillance cameras located far from each other. The system is fully automatic, and takes decisions about object detection and tracking using evidence collected from many pairs of cameras. Innovations that help us tackle the problem include a region-based stereo algorithm capable of finding 3D points inside an object knowing only the projections of the object (as a whole) in two views, a segmentation algorithm using bayesian classification and the use of occlusion analysis to combine evidence from different camera pairs.The system has been tested using different densities of people in the scene. This helps us determine the number of cameras required for a particular density of people. Experiments have also been conducted to verify and quantify the efficacy of the occlusion analysis scheme. 相似文献
969.
以工程为背景 ,介绍了基于 ISE平台 VHDL语言设计采用 FPGA实现 5 3位数据流的编解码和错误码的纠检错的方法 ,此方法采用并行处理 ,处理能力强 ,复杂度低 ,具有良好的工程应用前景 相似文献
970.