Asynchronous particle filter for tracking using non-synchronous sensor networks

This paper deals with the problem of tracking using a sensor network when the sensors are not synchronised. We propose a new algorithm called the asynchronous particle filter that, with much less computational burden than the traditional particle filter, has a slightly poorer performance. Thus, it is a good solution to real-time applications with non-synchronised sensors when high performance is required. The low computational burden of the method lies in the fact that we do not predict and update the state every time a measurement is collected. Its high performance is due to the fact that we account for the time instant at which each measurement was taken.     

Dynamic multi-cue tracking using particle filter

We consider the problem of decomposing audio into components that have different time frequency characteristics. For this, we model the components using different transforms and mixed norms applied on the transform domain coefficients. We formulate the problem as a search for a saddle point and derive algorithms through a primal-dual framework. We also discuss how to modify the primal-dual algorithms in order to derive a simpler heuristic scheme.     

一种简单有效的特征融合粒子滤波跟踪算法

粒子滤波算法是解决非高斯非线性条件下目标跟踪的实用算法,其优点在于能够融合目标的多种特征信息.灰度分布特征和直方图分布特征是灰度图像的重要特征,其各自的优点突出但也都存在一定的应用局限,只采用其中的单一特征往往不能得到稳定的跟踪结果.因此,提出一种将两种特征相融合的粒子滤波跟踪算法,将特征匹配的相似度融合到粒子权值的计算中,在保持特征原有优点的同时,利用二者的互补性,提高跟踪过程的稳定性.实验结果表明,采用灰度分布与直方图分布特征相融合的粒子滤波算法能更有效地跟踪目标.     

一种新型多特征融合粒子滤波视觉跟踪算法

针对单一视觉信息在动态变化环境下描述目标不够充分、跟踪目标不够稳定的缺点,提出了一种基于粒子滤波框架的新型多特征融合的视觉跟踪算法。采用颜色和形状信息来描述运动模型,通过民主合成策略将两种信息融合在一起,使得跟踪算法能根据当前跟踪形势自适应调整两种信息的权重以期达到最佳的最大似然比,实现信息间的优势互补。在设计粒子滤波跟踪算法时,利用自适应信息融合策略构建似然模型,提高了粒子滤波跟踪算法在复杂场景下的稳健性。实验结果表明,多特征融合跟踪算法不仅能准确、高效地跟踪目标,而且对光照、姿态变化引起的目标表观变化具有良好的鲁棒性。     

基于HOG特征的粒子滤波视频跟踪算法研究

在视频分析处理领域中,特别是在视频监控领域,目标跟踪正在受到越来越多的关注。由于在实际应用中,利用运动摄像机拍摄的视频中,会造成背景的运动和目标尺寸的变化,即使是在固定摄像机拍摄的视频中,也会由于背景环境的复杂,造成目标的丢失和干扰。针对这一问题,为了改善在复杂场景下的目标跟踪效果,提出了结合梯度方向直方图(HOG)和粒子滤波的目标跟踪算法。此方法是通过在传统粒子滤波算法的算法框架下,增加目标跟踪的特征,提高了跟踪的鲁棒性,并根据检测结果确定目标。实验仿真表明,与传统单一特征的粒子滤波算法相比,文中的算法更能准确有效地跟踪复杂背景下的动态目标。     

基于粒子滤波的弹道目标跟踪

弹道目标再入段的运动受到空气阻力、重力等力的影响,具有明显的非线性特征.传统的卡尔曼滤波是线性、高斯问题的最优滤波器,但无法处理非线性的估计问题.扩展卡尔曼滤波利用泰勒级数展开把非线性方程线性化,是解决非线性估计问题的有效算法;而近些年来出现的粒子滤波以其解决非线性问题的卓越性能,得到了迅速发展.文章对弹道目标再入段的运动特征进行研究,建立了目标的状态空间模型,并应用扩展卡尔曼滤波和粒子滤波实现了对弹道目标的跟踪.通过比较仿真结果,证明粒子滤波比扩展卡尔曼滤波精度更高,对噪声的抑制能力更强,也更稳定.因而具有重大的研究意义.     

Distributed multi-sensor particle filter for bearings-only tracking

In this article, the classical bearings-only tracking (BOT) problem for a single target is addressed, which belongs to the general class of non-linear filtering problems. Due to the fact that the radial distance observability of the target is poor, the algorithm-based sequential Monte-Carlo (particle filtering, PF) methods generally show instability and filter divergence. A new stable distributed multi-sensor PF method is proposed for BOT. The sensors process their measurements at their sites using a hierarchical PF approach, which transforms the BOT problem from Cartesian coordinate to the logarithmic polar coordinate and separates the observable components from the unobservable components of the target. In the fusion centre, the target state can be estimated by utilising the multi-sensor optimal information fusion rule. Furthermore, the computation of a theoretical Cramer–Rao lower bound is given for the multi-sensor BOT problem. Simulation results illustrate that the proposed tracking method can provide better performances than the traditional PF method.     

基于改进的粒子滤波算法的目标跟踪

为了解决粒子滤波算法在重采样过程中会造成粒子有效性和多样性的丧失,导致粒子贫化现象,提出了一种基于萤火虫算法的改进的粒子滤波算法。该算法在粒子滤波重要性采样过程中使用萤火虫算法,对粒子进行迭代寻优,使得采样出来的粒子更接近真实的后验概率;在粒子滤波重采样过程中,使用萤火虫算法使得粒子向高似然区域移动,提高粒子的多样性。实验结果表明,基于改进的粒子滤波算法目标跟踪效果优于传统的粒子滤波算法,可以在各种具有挑战性的条件下更好地进行目标跟踪。     

基于改进粒子滤波跟踪算法的运动视频跟踪

为了进一步提高目标跟踪的准确率,提出一种基于改进粒子滤波的运动视频跟踪算法。首先,通过高斯混合模型实现动态背景建模,从而降低噪声和局部动态背景的干扰;然后,在RGB颜色直方图分离的基础上,结合粒子滤波和迭代递归实现目标运动检测,提高了前景检测的准确性。仿真试验结果显示,相比典型粒子滤波算法、遗传粒子滤波和DCEM,改进粒子滤波跟踪算法得到的前景目标的轮廓更好,因此运动目标检测精确度更高且处理时间更短。     

A generic framework for tracking using particle filter with dynamic shape prior.

Tracking deforming objects involves estimating the global motion of the object and its local deformations as functions of time. Tracking algorithms using Kalman filters or particle filters (PFs) have been proposed for tracking such objects, but these have limitations due to the lack of dynamic shape information. In this paper, we propose a novel method based on employing a locally linear embedding in order to incorporate dynamic shape information into the particle filtering framework for tracking highly deformable objects in the presence of noise and clutter. The PF also models image statistics such as mean and variance of the given data which can be useful in obtaining proper separation of object and background.     

Fault detection in sensor information fusion Kalman filter

An approach to the test of the sensor information fusion Kalman filter is proposed. It is based on the introduced statistics of mathematical expectation of the spectral norm of a normalized innovation matrix. The approach allows for simultaneous test of the mathematical expectation and the variance of innovation sequence in real time and does not require a priori information on values of the change in its statistical characteristics under faults. Using this approach, fault detection algorithm for the sensor information fusion Kalman filter is developed.     

Object tracking with sparse representation and annealed particle filter

Recently, the L1 tracker is proposed for robust visual tracking. However, L1 tracker is still in traditional particle filter framework. As we know, particle filters suffer from some problems such as sample impoverishment. In this paper, we propose a new visual tracking algorithm, sparse representation based annealed particle filter, to further improve the performance of L1 tracker. As in L1 tracker, we find the tracking target at a new frame by sparsely representing each target candidate with both target and trivial templates. The sparsity is achieved by solving an \(\ell _{1}\) -regularized least squares problem. The candidate with the largest likelihood is taken as the tracking target. But different from L1 tracker, instead of tracking objects in the common particle filter framework, we solve the sparse representation problem in an annealed particle filter (APF) framework. In the APF framework, the sampling covariance and annealing factors are incorporated into the tracking process. The annealing strategy can achieve “smart sampling” to avoid generating invalid particles corresponding to infeasible targets. Both qualitative and quantitative evaluations on challenging video sequences are implemented to demonstrate the favorable performance in comparison with several other state-of-the-art tracking schemes.     

An improved Bernoulli particle filter for single target tracking

Single target tracking is widely applied in the current surveillance systems. The Bernoulli filter can complete the task of single target tracking using available measurements. However, the existing Bernoulli filters have estimation bias during the whole tracking process. Therefore, we present an improved Bernoulli filter and its particle implementation in this paper. Employed the weight optimization strategy, the under-estimated number of target is corrected by enlarging the maximal measurement-updated weight of sampling particle. In addition, the track identification strategy is applied to optimize number of the required particles and extract the actual target. Combined with the unscented transform for the complicated dynamic models, the nonlinear motion state of maneuvering target is effectively estimated. Besides, we extend the proposed filter in unknown clutter environment and estimate the mean clutter rate, which has significant application meaning owing to avoiding the assumption of the given detection profile. Finally, the numerical simulations demonstrate the tracking advantages with the promising results in comparison to the standard Bernoulli filter.     

Energy-efficient collaborative target tracking algorithm using cost-reference particle filtering in wireless acoustic sensor networks

Target tracking is one of the most important applications of wireless sensor networks. Optimized computation and energy dissipation are critical requirements to save the limited resource of sensor nodes. A new robust and energy-efficient collaborative target tracking framework is proposed in this article. After a target is detected, only one active cluster is responsible for the tracking task at each time step. The tracking algorithm is distributed by passing the sensing and computation operations from one cluster to another. An event-driven cluster reforming scheme is also proposed for balancing energy consumption among nodes. Observations from three cluster members are chosen and a new class of particle filter termed cost-reference particle filter (CRPF) is introduced to estimate the target motion at the cluster head. This CRPF method is quite robust for wireless sensor network tracking applications because it drops the strong assumptions of knowing the probability distributions of the system process and observation noises. In simulation experiments, the performance of the proposed collaborative target tracking algorithm is evaluated by the metrics of tracking precision and network energy consumption.     

Robust appearance-guided particle filter for object tracking with occlusion analysis

A major challenge for most tracking algorithms is how to address the changes of object appearance during tracking, incurred by large illumination, scale, pose variations and occlusions. Without any adaptability to these variations, the tracker may fail. In contrast, if adapts too fast, the appearance model is likely to absorb some improper part of the background or occluding objects. In this paper, we explore a tracking algorithm based on the robust appearance model which can account for slow or rapid changes of object appearance. Specifically, each pixel in appearance model is represented using mixture Gaussian models whose parameters are on-line learned by sequential kernel density approximation. The appearance model is then embedded into particle filter framework. In addition, an occlusion handling scheme is invoked to explicitly indicate outlier pixels and deal with occlusion events, thus avoiding the appearance model to be contaminated by undesirable outlier ‘thing’. Extensive experiments demonstrate that our appearance-based tracking algorithm can successfully track the object in the presence of dramatic appearance changes, cluttered background and even severe occlusions.     

基于粒子滤波的系数编码车辆跟踪方法

传统基于生成式的车辆跟踪方法仅考虑了目标信息,忽略了车辆背景信息,降低了目标与背景的表征能力.针对复杂背景条件下视觉导航对车辆跟踪精度的需求,提出了一种基于粒子滤波的系数编码车辆跟踪方法.该方法首先对获取的帧图像进行仿射变换归一化处理,并采用深度去噪自编码器对变换后的图像进行完备特征字典的生成;接着,采用稀疏编码对完备特征字典进行降维处理,消除网络高层目标特征的冗余信息,保留网络底层的高效关联特征;最后,将提取的深度稀疏编码特征应用到粒子滤波的框架内实现车辆的有效跟踪,有效克服了判别式跟踪方法无法处理遮挡问题的缺陷.实验结果表明,在尺度变化、光照变化以及遮挡等复杂环境下,本文方法将跟踪精度提升了17％,每秒处理的帧图像速度提升了64％.     

基于粒子滤波和稀疏表示的视频目标跟踪

文中将视频目标跟踪看成在粒子滤波框架下的稀疏表示问题,提出了具鲁棒性的视觉跟踪方法。在跟踪过程中,将目标的先验知识和目标状态及其观测结果联系起来构造贝叶斯概率模型,根据基本粒子滤波算法对目标位置进行估计。候选目标通过目标模板和琐碎模板稀疏表示,用l1范数稀疏正则化算法求解稀疏问题,选取具有最小残差的候选目标为跟踪结果。通过动态更新模板和非负性约束两种策略,使算法在目标遮挡、噪声、形变等各种干扰因素下,均达到了很好的跟踪性能。     

基于粒子滤波的烧结断面图像火焰区域跟踪

在铁矿石烧结过程中,烧结机尾断面图像中的火焰区域蕴含着大量烧结特征信息.为有效识别烧结断面火焰核心区域,提出了改进的粒子滤波算法对烧结断面图像进行火焰区域跟踪.在经典粒子滤波算法中引入RGB颜色空间生成带权粒子.同时,烧结过程中火焰区域可能合并、分裂及脱落,对粒子滤波算法中重采样方法进行权值优化、粒子舍弃与重采样策略优...     

改进粒子滤波算法及其在目标跟踪中的应用

雷达目标跟踪量测系统常受到闪烁噪声干扰,导致传统滤波算法的滤波性能急剧下降甚至发散。文中提出了改进粒子滤波算法,利用扩展卡尔曼滤波产生重要性概率密度函数。提出改进的重采样策略,提高采样粒子的有效性。将文中算法与PF及EKPF算法进行了仿真比较,结果表明该算法具有较优的跟踪性能。     

基于K-均值聚类的改进粒子滤波跟踪算法

针对粒子滤波算法因计算量过大带来的实时性问题,文中提出一种基于K-means聚类的粒子滤波目标跟踪算法。该算法利用K-means算法对重采样后的粒子进行聚类以达到进一步寻优的目的,这样可以得到更为有效的粒子集,从而大大减小计算的复杂度。通过与基于传统粒子滤波算法的实验数据的分析表明提出的算法可以有效地减小计算量,改善粒子滤波算法的实时性问题。同时,相比于传统粒子滤波目标跟踪算法,改进算法的鲁棒性也有所提高。