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.     

Collaborative tracking via particle filter in wireless sensor networks

Target tracking is one of the main applications of wireless sensor networks. Optimized computation and energy dissipation are critical requirements to save the limited resource of the sensor nodes. A framework and analysis for collaborative tracking via particle filter are presented in this paper Collaborative tracking is implemented through sensor selection, and results of tracking are propagated among sensor nodes. In order to save communication resources, a new Gaussian sum particle filter, called Gaussian sum quasi particle filter, to perform the target tracking is presented, in which only mean and covariance of mixands need to be communicated. Based on the Gaussian sum quasi particle filter, a sensor selection criterion is proposed, which is computationally much simpler than other sensor selection criterions. Simulation results show that the proposed method works well for target tracking.     

基于RB粒子滤波的多传感器目标跟踪融合算法

构建面向多传感器信息融合系统的粒子滤波(PF)器是拓展采样型非线性滤波应用领域的关键,针对PF在多传感器融合目标跟踪系统的有效实现问题,提出了一种基于Rao-Blackwellized(RB)PF(RB-PF)的多传感器目标融合跟踪(MT-RB-PF)算法。首先,利用RB建模技术实现跟踪系统非线性状态估计的降维处理;其次,结合多传感器融合系统特点,给出一种多量测下粒子权重优化新方法用以改善粒子权重度量的可靠性和稳定性;最终,通过标准PF和卡尔曼滤波(KF)实现非线性和线性状态分量的估计,并利用状态重构方法构建当前时刻的状态估计值。理论分析和仿真实验验证了算法的有效性。     

Target tracking by lightweight blind particle filter in wireless sensor networks

For realizing robust target tracking with wireless sensor networks in the circumstance where the propagation parameters of the characteristic signal emitted by the target are unknown, a novel tracking algorithm under the particle filter framework is proposed. We propose a scheme to realize particle weight calculation without the prior knowledge about the propagation parameters of the target's characteristic signal. With the use of the monotonic relationship of the distance and the received signal strength, we define the signal characteristic sequence and particle distance sequence and utilize the modified sequence distance between the signal characteristic sequence and the particle distance sequence as the criterion to calculate the particle weight blindly with simple lightweight operations. Simulation results demonstrate the effectiveness of the proposed algorithm. Copyright © 2011 John Wiley & Sons, Ltd.     

基于改进粒子滤波和自适应融合的目标跟踪

针对复杂环境下视频目标跟踪精确度低的问题,提 出了一种基于混合迭代无迹粒子滤波(HI-UPF)和关联系数自 适应融合的目标跟踪算法。首先采用统计线性回归的方法对无迹变换进行优化,提出了HI- UPF,不 仅提升了滤波精度,而且有效降低了算法的时间消耗;其次基于关联系数,采用一种自适应 融合方法,实现了加性 融合和乘性融合的自适应切换,并根据关联系数提出一种改进的自适应加性融合方法。仿真 实验表明,本文方法对 于复杂条件下的目标跟踪具有较高的精度和较强的鲁棒性。     

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.     

基于特征融合的粒子滤波目标跟踪新方法

针对传统粒子滤波(PF)算法采用单一颜色特征建模 跟踪目标性能差的缺陷,提出一种颜色特征与纹理特 征相融合的PF目标跟踪新算法。首先,采用一种具有抗噪声和保护纹理边缘的全局中值二值 模式 (GMBP)纹理算子,对模板图像进行局部差绝对值处理,得到幅 值序列模板,将幅值序列模板内的中值作为模板的阈值,与模板邻域比较获得新的纹理图像 ;然后,与 具有光照不变特性的局部二值模式(LBP)纹理算子结合,形成一种(GMLBP)新的纹理描述算子 。最后,分别计算GMLBP纹理特征粒子权值和HSV颜色特征粒子权 值,并依据权值大小确定融合系数,对纹理特征粒子权值和颜色特征粒子权值进行线 性融合,再对融合后粒子权值进行归一化处理,从而得到目标位置状态的最终估计值。对比 实验结果表明, 相对于单一颜色特征的目标跟踪算法,所提算法捕捉目标位置准确且具有更低的平均跟踪误 差,其平均误差降低了近2倍。     

Robust tracking algorithm for wireless sensor networks based on improved particle filter

Benefitting from its ability to estimate the target state's posterior probability density function (PDF) in complex nonlinear and non‐Gaussian circumstance, particle filter (PF) is widely used to solve the target tracking problem in wireless sensor networks. However, the traditional PF algorithm based on sequential importance sampling with re‐sampling will degenerate if the latest observation appear in the tail of the prior PDF or if the observation likelihood is too peaked in comparison with the prior. In this paper, we propose an improved particle filter which makes full use of the latest observation in constructing the proposal distribution. The quality prediction function is proposed to measure the quality of the particles, and only the high quality particles are selected and used to generate the coarse proposal distribution. Then, a centroid shift vector is calculated based on the coarse proposal distribution, which leads the particles move towards the optimal proposal distribution. Simulation results demonstrate the robustness of the proposed algorithm under the challenging background conditions. Copyright © 2010 John Wiley & Sons, Ltd.     

复杂背景下多信息融合的粒子滤波跟踪算法

将颜色和运动这两种信息融合进粒子滤波跟踪器,并提出分层抽样的方法,克服了利用单一信源所带来的跟踪不稳定问题;与典型的基于边缘特征或仅基于颜色信息的粒子滤波器相比,计算简单,并能够有效解决由于目标形状或颜色模糊而产生的跟踪困难问题.实验结果表明,该粒子滤波融合算法在复杂背景下能够稳健可靠的跟踪目标.     

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。     

一种导向粒子滤波跟踪算法

粒子滤波算法在运动目标跟踪方面有着广泛的使用,粒子滤波中的重采样是解决粒子退化的一种重要方法,但是重采样会导致粒子的多样性的丧失。针对这个问题,改进粒子滤波算法,改进过程中结合了导向滤波的基本思想,因此将这种方法称为导向粒子滤波跟踪算法。导向滤波是近几年提出的一种新的滤波方式,与传统滤波相比,它在滤波的时候会引入一幅指导图像,鉴于这个思想,我们在进行粒子滤波的时候,引入一种导向粒子作为一个指导量,来保留一些目标图像上的信息。实验证明了这种算法可以更好地对目标进行定位跟踪。     

多特征融合的优化粒子滤波红外目标跟踪

针对粒子滤波重采样中粒子贫化问题,采用了权值选择的优化方法,对每个粒子的权值进行排序,选取其中权值较大的粒子参与跟踪估计,使权值较小的粒子有机会参与下一状态的估计,保证参与状态估计的大部分粒子具有多样性,有效克服粒子贫化现象。为了进一步提高跟踪性能,根据红外目标成像特点,融合目标梯度特征和灰度特征建立观测模型,并根据置信度实时调整每个特征对跟踪结果的影响,且自适应更新模板。经仿真验证,红外目标在复杂背景或遇到遮挡情况下,该算法能够精确鲁棒地跟踪目标。     

基于粒子群优化和M-H采样粒子滤波的传感器网络目标跟踪方法

针对实际应用条件下传感器节点的观测数据与目标动态参数间呈现为非线性关系的特性,提出了一种基于粒子群优化和M-H抽样粒子滤波的传感器网络目标跟踪方法。该方法采用分布式结构,在动态网络拓扑结构下,由粒子群优化和M-H抽样技术实现滤波中的重抽样过程,抑制粒子退化现象,并通过粒子间共享历史信息,降低单个粒子历史状态间的相关性使各粒子能快速收敛至最优分布,从而实现高精度的目标跟踪效果。仿真结果表明,相比现有的基于信息粒子滤波和并行粒子滤波技术的传感器网络目标跟踪方法,所提出的方法能降低网络总能耗,同时保证目标跟踪的精度。     

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.