In this paper, mean shift algorithm and adaptive Kalman filter have been both utilized to realize object tracking in video sequences. mean shift algorithm cannot give good results when the position of the tracked obje...
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ISBN:
(纸本)9781467373869
In this paper, mean shift algorithm and adaptive Kalman filter have been both utilized to realize object tracking in video sequences. mean shift algorithm cannot give good results when the position of the tracked object is changed rapidly between sequential frames or the tracked object is occluded. In this paper, the first position of the tracked object is predicted by Kalman filter then mean shift algorithm starts to seek the object in this position. Bhattacharyya coefficient which is obtained from mean shift algorithm, is used to instantly update Kalman filters error covariance matrix and determine whether object is occluded or not. Experimental results demonstrate that the proposed method has been more efficient technique as compared to standard mean shift algorithm in case of occlusion and fast object tracking.
A method for object tracking combining the accuracy of meanshift with the robustness to occlusion of Kalman filtering is proposed. At first, an estimation of the object's position is obtained by the meanshift tr...
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ISBN:
(纸本)9783642128417
A method for object tracking combining the accuracy of meanshift with the robustness to occlusion of Kalman filtering is proposed. At first, an estimation of the object's position is obtained by the meanshift tracking algorithm and it is treated as the observation for a. Kalman filter. Moreover, we propose a dynamic scheme for the Kalman filter as the elements of its state matrix are updated on-line depending on a measure evaluating the quality of the observation. According to this measure, if the target is not occluded the observation contributes to the update equations of the Kalman filter state matrix. Otherwise, the observation is not taken into consideration. Experimental results show significant improvement with respect to the standard meanshift method both in terms of accuracy and execution time.
Robust real-time ship detection and tracking for visual images automatically has become one of the crucial requirements for numerous situations. In order to improve the performance of automatic ship target detection a...
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ISBN:
(纸本)9781509062386
Robust real-time ship detection and tracking for visual images automatically has become one of the crucial requirements for numerous situations. In order to improve the performance of automatic ship target detection and tracking system, a novel method based on meanshift is proposed for automatic detection and tracking of ship in the corrected video sequences. Firstly, video frames are corrected based on real-time attitude of the imaging equipment in order to decrease the drift of the ship target from frame to frame. Secondly, sea horizon is extracted based on Ostu algorithm and Hough transform. Thirdly, the ship location is detected based on the detection of grayscale peak. Finally, the ship is automatically tracked by using the mean shift algorithm. The result shows that this method has not only improved the robustness of the system against the shaking while tracking the ships, but also achieved a high success rate of tracking ships automatically in corrected video sequences.
The underlying principle of pitch determination based on the mean shift algorithm is studied, and the cause of pitch error propagation in the original pseudo code is analyzed. The problem of error propagation is solve...
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The underlying principle of pitch determination based on the mean shift algorithm is studied, and the cause of pitch error propagation in the original pseudo code is analyzed. The problem of error propagation is solved by choosing an appropriate initial pitch candidate F00. The theoretical choice guideline in a pitch epoch is obtained as ensuring the true pitch F0 satisfying F00/2 〈 F0 〈 3F00/2. The validity of the choice guideline is verified by the F00 experiment. meanwhile, the algorithm is extended to the pitch determination in the noisy case and compared with the method of subharmonic-to-harmonic ratio (SHR). The experimental results show that the improved algorithm bears comparison with SHR and it runs much faster than SHR.
Directional data consist of observations distributed on a (hyper)sphere, and appear in many applied fields, such as astronomy, ecology, and environmental science. This paper studies both statistical and computational ...
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Directional data consist of observations distributed on a (hyper)sphere, and appear in many applied fields, such as astronomy, ecology, and environmental science. This paper studies both statistical and computational problems of kernel smoothing for directional data. We generalize the classical mean shift algorithm to directional data, which allows us to identify local modes of the directional kernel density estimator (KDE). The statistical convergence rates of the directional KDE and its derivatives are derived, and the problem of mode estimation is examined. We also prove the ascending property of the directional mean shift algorithm and investigate a general problem of gradient ascent on the unit hypersphere. To demonstrate the applicability of the algorithm, we evaluate it as a mode clustering method on both simulated and real-world data sets.
In this paper, a joint gesture tracking method combining particle filter and mean shift algorithm is proposed to improve the accuracy and robustness of the system. During the slow movement of the human hand, the avera...
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In this paper, a joint gesture tracking method combining particle filter and mean shift algorithm is proposed to improve the accuracy and robustness of the system. During the slow movement of the human hand, the average movement of the particles is first used to cause most of the particles to drift into the gesture area. In the case where the movement of the human hand is faster or there is occlusion, when the meanshift of the particle is performed, if the region of the gesture is not detected, the particle will return to the state before the drift, and then the next frame is processed. The method can directly calculate the position of the gesture based on the particles used for subsequent testing, and can save the tracking time of the algorithm. Through experimental simulation, compared with the Cam-shiftalgorithm, when the sampling point of the joint tracking algorithm proposed in this paper is 200, the tracking accuracy is improved to 95.2%. Compared with 90.6% of the Cam-shiftalgorithm, the tracking time is reduced from 83.7ms to 25.8ms. Therefore, the proposed algorithm can greatly improve the tracking accuracy and real-time, and can also effectively reduce the impact of complex environments on the tracking effect.
Accurately locating the video target in the process of occlusion and recurrence will be very important for effective follow-up of the target For the problem of poor applicability of meanshift and its improved algorit...
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Accurately locating the video target in the process of occlusion and recurrence will be very important for effective follow-up of the target For the problem of poor applicability of meanshift and its improved algorithm when the target is heavily occluded, this paper proposes an anti-occlusion video target tracking algorithm based on prediction and re-matching strategy. Firstly, dynamically combining the mean shift algorithm with the Kalman filter, this paper achieves stable tracking of un-occluded target. Secondly, when the target is occluded, Kalman filter is combined with the target prior information to predict the position of the occluded target. Finally, in the recurrence process of occluded targets, the target is re- matched through the normalized cross-correlation method to obtain target optimal position, and then the target can be quickly and accurately located. The simulation results show that the proposed method has strong anti-occlusion and reliability tracking in the video target tracking process. (C) 2018 Elsevier Inc. All rights reserved.
meanshift is one of the popular clustering algorithms and can be used to partition a digital image into semantically meaningful regions in an unsupervised manner. However, due to its prohibitively high computational c...
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meanshift is one of the popular clustering algorithms and can be used to partition a digital image into semantically meaningful regions in an unsupervised manner. However, due to its prohibitively high computational complexity, a grid-based approach, called meanshift++, has recently been proposed and succeeded to surprisingly reduce the computational complexity of meanshift. Nevertheless, we found that meanshift++ still has computational redundancy and there is room for improvement in terms of accuracy and runtime;thus, we propose an improvement to meanshift++, named alpha-meanshift++. We first attempt to minimize the computational redundancy by using an additional hash table. Then, we introduce a speedup factor (alpha) to reduce the number of iterations required until convergence, and we use more neighboring grid cells for the same bandwidth to improve accuracy. Through intensive experiments on image segmentation benchmark datasets, we demonstrate that alpha-meanshift++ can run 4.1-4.6 x faster on average (but up to 7 x) than meanshift CC and achieve better image segmentation quality.
We present an approach that incorporates multi-information, including intensity value, spatial relation, and local standard deviation information of the pixels in target region, into kernel density estimation for cons...
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We present an approach that incorporates multi-information, including intensity value, spatial relation, and local standard deviation information of the pixels in target region, into kernel density estimation for constructing the kernel-based infrared (IR) target model. The incorporated information can complement each other for a target-tracking task. This constructed target model is evaluated based on the relative entropy of the two classes and is applied in a meanshift tracking system for IR target tracking to verify the effectiveness. (c) 2006 Society of Photo-Optical Instrumentation Engineers.
This study presents a robust approach for characterization of multi-layered forests using airborne laser scanning (ALS) data. Fuel mapping or biomass estimation requires knowing the diversity and boundaries of the for...
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This study presents a robust approach for characterization of multi-layered forests using airborne laser scanning (ALS) data. Fuel mapping or biomass estimation requires knowing the diversity and boundaries of the forest patches, as well as their spatial pattern. This includes the thickness of the main vegetation layers, but also the spatial arrangement and size of the individual plants that compose each stratum. In order to decompose the ALS point cloud into genuine 3-D segments corresponding to individual vegetation features, such as shrubs or tree crowns, we apply a statistical approach based on the mean shift algorithm. The segments are progressively assigned to a forest layer: ground vegetation, understory or overstory. Our method relies on a single biophysically meaningful parameter, the kernel bandwidth, which is related to the local forest structure. It is validated on 44 plots of a Portuguese forest, composed mainly of eucalyptus (Eucalyptus globulus Labill.) and maritime pine (Pinus pinaster Ait.) trees. The number of detected trees varies with the dominance position: from 98.6% for the dominant trees to 12.8% for the suppressed trees. Linear regression models explain up to 70% of the variability associated with ground vegetation and understory height. (c) 2012 Elsevier Inc. All rights reserved.
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