A dual-kernel-based tracking approach for visual target

A dual-kernel-based tracking approach for visual target is proposed in this paper. The similarity between candidate and target model, and the contrast between candidate and its neighboring background are considered simultaneously when evaluating a target candidate. The similarity is measured by Bhattacharyya coefficient while the contrast is calculated with Jensen-Shannon divergence, and they are adaptively fused into a novel objective function. By maximizing the linear approximation of objective function, a dual-kernel target location-shift relation from current location to a new location is induced. According to the location-shift relation, the optimal target location can be recursively gained in the mean shift procedure. Experimental evaluations on several image sequences demonstrate that the proposed algorithm can gain more accurate target location and better identification power to false target, and it is also robust to deformation and partial occlusion.     

A grid-based Bayesian approach to robust visual tracking

Visual tracking encompasses a wide range of applications in surveillance, medicine and the military arena. There are however roadblocks that hinder exploiting the full capacity of the tracking technology. Depending on specific applications, these roadblocks may include computational complexity, accuracy and robustness of the tracking algorithms. In the paper, we present a grid-based algorithm for tracking that drastically outperforms the existing algorithms in terms of computational efficiency, accuracy and robustness. Furthermore, by judiciously incorporating feature representation, sample generation and sample weighting, the grid-based approach accommodates contrast change, jitter, target deformation and occlusion. Tracking performance of the proposed grid-based algorithm is compared with two recent algorithms, the gradient vector flow snake tracker and the Monte Carlo tracker, in the context of leukocyte (white blood cell) tracking and UAV-based tracking. This comparison indicates that the proposed tracking algorithm is approximately 100 times faster, and at the same time, is significantly more accurate and more robust, thus enabling real-time robust tracking.     

A fuzzy inference approach to template-based visual tracking

The tracking of visual features using appearance models is a well studied but still open area of computer vision. In the absence of knowledge about the structural constraints of the tracked object, the validity of the model can be compromised if only appearance information is used. We propose a fuzzy inference scheme that can be used to selectively update a given template-based model in tracking tasks. This allows us to track moving objects under translation, rotation, and scale changes with minimal feature drift. Moreover, no rigidity constraint needs to be enforced on the moving target. Some experiments have been performed using several targets, and the results are very close to the ground truth paths. The computational cost of our approach is low enough to allow its application in real-time tracking using modest hardware requirements.     

Multi-human tracking using part-based appearance modelling and grouping-based tracklet association for visual surveillance applications

Multimedia Tools and Applications - Although much progress has been made in multi-object tracking in recent decades due to its variety of applications including visual surveillance, traffic...     

A multi-cue mean-shift target tracking approach based on fuzzified region dynamic image fusion

Traditional target tracking algorithms based on single sensor images are unstable and have low accuracy. Based on regional target detection and fuzzy region rules, a fuzzy region-based multi-sensor image fusion approach is proposed in this paper. The similarity measure weight is adapted to this dynamic image fusion algorithm, while the tracking method uses the proposed multi-cue mean-shift tracking algorithm. Three experimental results using real world image sequences are evaluated using the steady state square root mean error. The fusion and tracking experiments indicate that the proposed approach is effective and efficient when aiming at a target moving from one area to a different area, which meets the robustness and real-time requirements.     

一种基于目标先验信息的视觉跟踪算法

针对运动目标跟踪过程中出现的遮挡问题,提出了基于目标先验信息的视觉显著性遮挡目标跟踪算法。在粒子滤波框架下,利用目标先验信息生成视觉显著图,并根据粒子区域颜色特征与目标颜色特征模板之间的相似度来判断遮挡情况。当遮挡发生时,提高特征融合公式中显著性特征的融合权重,从而充分利用目标未被遮挡部分信息来完成跟踪。实验结果表明,利用目标先验信息的目标跟踪算法能显著提升跟踪遮挡目标的鲁棒性。     

A visual tracking algorithm via confidence-based multi-feature correlation filtering

Multimedia Tools and Applications - Object tracking is an important issue in many practical computer vision applications, such as video surveillance, self-driving,and social scene understanding....     

Adaptive visual tracking using the prioritized Q-learning algorithm: MDP-based parameter learning approach

This paper introduces an adaptive visual tracking method that combines the adaptive appearance model and the optimization capability of the Markov decision process. Most tracking algorithms are limited due to variations in object appearance from changes in illumination, viewing angle, object scale, and object shape. This paper is motivated by the fact that tracking performance degradation is caused not only by changes in object appearance but also by the inflexible controls of tracker parameters. To the best of our knowledge, optimization of tracker parameters has not been thoroughly investigated, even though it critically influences tracking performance. The challenge is to equip an adaptive tracking algorithm with an optimization capability for a more flexible and robust appearance model. In this paper, the Markov decision process, which has been applied successfully in many dynamic systems, is employed to optimize an adaptive appearance model-based tracking algorithm. The adaptive visual tracking is formulated as a Markov decision process based dynamic parameter optimization problem with uncertain and incomplete information. The high computation requirements of the Markov decision process formulation are solved by the proposed prioritized Q-learning approach. We carried out extensive experiments using realistic video sets, and achieved very encouraging and competitive results.     

A novel approach to 3-D gaze tracking using stereo cameras

A novel approach to three-dimensional (3-D) gaze tracking using 3-D computer vision techniques is proposed in this paper. This method employs multiple cameras and multiple point light sources to estimate the optical axis of user's eye without using any user-dependent parameters. Thus, it renders the inconvenient system calibration process which may produce possible calibration errors unnecessary. A real-time 3-D gaze tracking system has been developed which can provide 30 gaze measurements per second. Moreover, a simple and accurate calibration method is proposed to calibrate the gaze tracking system. Before using the system, each user only has to stare at a target point for a few (2-3) seconds so that the constant angle between the 3-D line of sight and the optical axis can be estimated. The test results of six subjects showed that the gaze tracking system is very promising achieving an average estimation error of under 1 degrees.     

A constrained optimization approach for an adaptive generalized subspace tracking algorithm

In this paper, we present an orthonormal version of the generalized signal subspace tracking. It is based on an interpretation of the generalized signal subspace as the solution of a constrained minimization task. This algorithm, referred to as the CGST algorithm, guarantees the C_x-orthonormality of the estimated generalized signal subspace basis at each iteration which C_x denotes the correlation matrix of the sequence x(t). An efficient implementation of the proposed algorithm enhances applicability of it in real time applications.     

基于视觉显著性的均值漂移跟踪算法

为解决突变运动下的目标跟踪问题,提出了一种基于视觉显著性的均值漂移跟踪算法,将视觉注意机制运用到均值漂移跟踪框架中,利用时空显著性算法对视频序列进行检测,生成视觉显著图,从视觉显著图对应的显著性区域中建立目标的颜色特征表示模型来实现运动目标跟踪.实验结果表明:该算法在摄像机摇晃等动态场景下可以较准确检测出时空均显著的目标,有效克服了在运动目标发生丢失和遮挡等情况下跟踪不稳定的问题,具有较强的鲁棒性,从而实现复杂场景下目标较准确的跟踪.     

A novel foreground region analysis using NCP-DBP texture pattern for robust visual tracking

Robust visual tracking is the important stage in the computer vision applications such as robotics, man-free control systems, and the visual surveillance. Accurate motion states estimation and the target representation in visual tracking system are based on the appearances of the target. The factor affects the learning of target representation is the accumulated error due to the pose, illumination changes, and the uneven background. The presence of dynamic background and the shadowing effects causes the visual drift and destructive information. Besides, the misclassification of target region induces the false detection of moving objects. The K-means and Fuzzy-C-means clustering algorithms are available to segment the foreground/background and suppress the shadow region on the basis of the non-changing background of the surveillance area. This paper proposes the novel background normalization technique with textural pattern analysis to suppress the shadow region. The Neighborhood Chain Prediction (NCP) algorithm is used to cluster the uneven background and the Differential Boundary Pattern (DBP) extracts the texture of the video frame to suppress the shadow pixels present in the frame. The lower intensity estimation and the prediction of the area around the lower intensity in proposed work enhance the pixels for shadow removal. The shadow-free frame split up into several grids and the histograms of features are extracted from the grid formatted frame. Finally, the Machine Level Classification (MLC) finds the matching grid corresponds to the tracking region and provides the binary labeling to separate the background and foreground. The proposed DBP-based visual tracking system is high robustness over the sudden illumination changes and the dynamic background due to the texture pattern analysis. The comparison of proposed NCP-DBP combination with the existing segmentation techniques regarding the accuracy, precision, recall, F-measure, success and error rate assured the effectiveness in visual tracking applications.     

A multiCell visual tracking algorithm using multi-task particle swarm optimization for low-contrast image sequences

In terms of the varying number of cell population, shape deformation, collision and uneven movement, a novel method based on multi-task particle swarm optimization (PSO) algorithm without explicit detection module, named MTPSO tracking method, is developed for automatic tracking of biological cells in time-lapse low-contrast microscopy image sequences. For tracking existing cells from the previous frames, a PSO-based tracking module is firstly implemented to give the initial positions of existing cells according to the previous estimated state of each cell, then a PSO-based contour module is proposed to determine the corresponding contour of each cell and finally achieve a precise position tracking by an iterative centroid updating process. For tracking new appearing cells at the current frame, a PSO-based discovery module, followed by the aforementioned PSO-based contour module, is proposed to search for new potential cells through appropriate initialization of particle swarm and searching mechanism. MTPSO tracking method is tested over a number of different real cell image sequences and is shown to provide high accuracy both in position and contour estimate of each cell in various challenging cases. Furthermore, it is more competitive against the state-of-the-art multi-object tracking methods in terms of performance measures such as FAR, FNR, LTR, and LSR.     

A novel feature-based approach to characterize algorithm performance for the traveling salesperson problem

Meta-heuristics are frequently used to tackle NP-hard combinatorial optimization problems. With this paper we contribute to the understanding of the success of 2-opt based local search algorithms for solving the traveling salesperson problem (TSP). Although 2-opt is widely used in practice, it is hard to understand its success from a theoretical perspective. We take a statistical approach and examine the features of TSP instances that make the problem either hard or easy to solve. As a measure of problem difficulty for 2-opt we use the approximation ratio that it achieves on a given instance. Our investigations point out important features that make TSP instances hard or easy to be approximated by 2-opt.     

A novel approach for automated land partitioning using genetic algorithm

Land consolidation is an important tool to prevent land fragmentation and enhance agricultural productivity. Land partitioning is one of the most significant problems within the land consolidation process. This process is related to the subdivision of a block having non-uniform geometric shapes. Land partitioning determines the location of new land parcels and is a complex problem containing many conflicting demands, so conventional programming techniques are not sufficient for this NP optimization problem. Therefore, it is necessary to have an intelligent system with a standard decision-making mechanism capable of processing many criteria simultaneously and evaluating a number of different solutions in a short time. To overcome this problem and accelerate the land partitioning process, we proposed automated land partitioning using a genetic algorithm (ALP-GA). Besides the parcel's size, shape and land value, the proposed method evaluates fixed facilities, and the degree and location of cadastral parcels to generate a land partitioning plan. The proposed method automated the land partitioning process using an intelligent system and was implemented over a real project area. Experimental study shows that the proposed method is more successful and efficient than the designer with respect to the results meeting the objective function. In addition, the land partition process is greatly simplified by the proposed method.     

A part-based attention network for person re-identification

Multimedia Tools and Applications - Person re-identification (re-id) is the task of recognizing images of the same pedestrian captured by different cameras with non-overlapping views. Person re-id...