A strong tracking nonlinear robust filter for eye tracking

Non-intrusive methods for eye tracking are important for many applications of vision-based human computer interaction. However, due to the high nonlinearity of eye motion, how to ensure the robustness of external interference and accuracy of eye tracking pose the primary obstacle to the integration of eye movements into today’s interfaces. In this paper, we present a strong tracking unscented Kalman filter (ST-UKF) algorithm, aiming to overcome the difficulty in nonlinear eye tracking. In the proposed ST-UKF, the Suboptimal fading factor of strong tracking filtering is introduced to improve robustness and accuracy of eye tracking. Compared with the related Kalman filter for eye tracking, the proposed ST-UKF has potential advantages in robustness and tracking accuracy. The last experimental results show the validity of our method for eye tracking under realistic conditions.     

2D human body tracking with Structural Kalman filter

Tracking moving objects is one of the most important techniques in motion analysis and understanding, and it has many difficult problems to solve. Especially, estimating and identifying moving objects, when the background and moving objects vary dynamically, are very difficult. It is possible under such a complex environment that targets may disappear totally or partially due to occlusion by other objects. The Kalman filter has been used to estimate motion information and use the information in predicting the appearance of targets in the succeeding frames. In this paper, we propose another version of the Kalman filter, to be called Structural Kalman filter, which can successfully work its role of estimating motion information under such a deteriorating condition as occlusion. Experimental results show that the suggested approach is very effective in estimating and tracking non-rigid moving objects reliably.     

A parallel and robust object tracking approach synthesizing adaptive Bayesian learning and improved incremental subspace learning

This paper presents a novel tracking algorithm which integrates two complementary trackers. Firstly, an improved Bayesian tracker(B-tracker) with adaptive learning rate is presented. The classification score of B-tracker reflects tracking reliability, and a low score usually results from large appearance change. Therefore, if the score is low, we decrease the learning rate to update the classifier fast so that B-tracker can adapt to the variation and vice versa. In this way, B-tracker is more suitable than its traditional version to solve appearance change problem. Secondly, we present an improved incremental subspace learning method tracker(Stracker). We propose to calculate projected coordinates using maximum posterior probability, which results in a more accurate reconstruction error than traditional subspace learning tracker. Instead of updating at every time, we present a stopstrategy to deal with occlusion problem. Finally, we present an integrated framework(BAST), in which the pair of trackers run in parallel and return two candidate target states separately. For each candidate state, we define a tracking reliability metrics to measure whether the candidate state is reliable or not, and the reliable candidate state will be chosen as the target state at the end of each frame. Experimental results on challenging sequences show that the proposed approach is very robust and effective in comparison to the state-of-the-art trackers.     

A local-motion-based probabilistic model for visual tracking

Color-based tracking is prone to failure in situations where visually similar targets are moving in a close proximity or occlude each other. To deal with the ambiguities in the visual information, we propose an additional color-independent visual model based on the target's local motion. This model is calculated from the optical flow induced by the target in consecutive images. By modifying a color-based particle filter to account for the target's local motion, the combined color/local-motion-based tracker is constructed. We compare the combined tracker to a purely color-based tracker on a challenging dataset from hand tracking, surveillance and sports. The experiments show that the proposed local-motion model largely resolves situations when the target is occluded by, or moves in front of, a visually similar object.     

一种快速鲁棒的动态入手跟踪方法

介绍了一种基于肤色与手形的动态人手跟踪方法。根据检测过程中所用到的人手基本特征,提出了一种基于色度一饱和度自适应阂值肤色分割与成对几何直方图（PGH）匹配的人手图像检测方法。为了克服跟踪过程中背景色干扰的问题,实现了基于Kalman滤波器的预测跟踪。实验结果表明,该动态人手跟踪方法计算简便、实时性好、跟踪精度高,可应用在大多数复杂场景。     

A hierarchical feature fusion framework for adaptive visual tracking

A Hierarchical Model Fusion (HMF) framework for object tracking in video sequences is presented. The Bayesian tracking equations are extended to account for multiple object models. With these equations as a basis a particle filter algorithm is developed to efficiently cope with the multi-modal distributions emerging from cluttered scenes. The update of each object model takes place hierarchically so that the lower dimensional object models, which are updated first, guide the search in the parameter space of the subsequent object models to relevant regions thus reducing the computational complexity. A method for object model adaptation is also developed. We apply the proposed framework by fusing salient points, blobs, and edges as features and verify experimentally its effectiveness in challenging conditions.     

GRM: Gaussian response module for visual tracking

Online Discriminative Correlation Filters have excellent performance in visual object tracking. It always divides the tracking network as a classification network and a regression network, which makes the regression network lack classification information and makes it hard to leverage its advantages. To address this problem, we propose the ATOM_GRM tracker to append the classification information to the network. Specifically, we design static and dynamic Gaussian response modules to encode the raw target position from classifier to regression network by multistage. In Particular, the parameters and fusion method of two Gaussian response modules is designed in different ways according to their location in the network. Moreover, we propose the ratio of height and width of the bounding box instead of intersection of union as the predictor, and two auxiliary training heads are used in the regression network. It makes the regression network better distinguish bounding boxes. Extensive experiments conducted on four public benchmarks, i.e., OTB100, GOT10k, LaSOT, Trackingnet, demonstrate the effectiveness of the proposed method. The proposed ATOM_GRM achieves 0.556 → 0.596 AO compared with the baseline ATOM on GOT10k.     

视觉目标跟踪方法研究综述

目的 随着军事侦察任务设备的发展,红外与可见光侦察技术成为军事装备中的主要侦察手段。研究视觉目标跟踪技术对提高任务设备的全天候目标侦察、目标跟踪、目标定位等战场情报获取能力具有重要意义。目前,对视觉目标跟踪技术的研究越来越深入,目标跟踪的方法和种类也越来越丰富。本文对目前应用较为广泛的4种视觉目标跟踪方法进行研究综述,为后续国内外研究者对目标跟踪相关理论及发展研究工作提供基础。方法 通过对视觉目标跟踪技术难点问题进行分析,根据目标跟踪方法建模方式的不同,将视觉目标跟踪方法分为生成式模型方法与判别式模型方法。分别对生成式模型跟踪算法中的均值漂移目标跟踪方法和粒子滤波目标跟踪方法,判别式模型跟踪算法中的相关滤波目标跟踪方法和深度学习目标跟踪方法进行研究。首先分别对4种跟踪算法的基本原理进行介绍,然后针对4种跟踪算法基本原理的不足和对应目标跟踪中的难点问题进行分析,最后针对目标跟踪的难点问题,给出对应算法的主流改进方案。结果 针对视觉目标跟踪相关技术研究进展,结合无人机侦察任务需求,对跟踪算法实际应用中存在的重点解决问题与相关目标跟踪的难点问题进行分析,给出目前的解决方案与不足,探讨研究未来无人机目标侦察跟踪技术的发展方向。结论 视觉目标跟踪技术已经取得了显著的进展,在侦察任务中的应用越来越广泛。但目标跟踪技术仍然是非常具有挑战性的问题,目标跟踪中的相关理论有待进一步完善和改进,由于实际应用中的场景复杂,目标跟踪的难点问题的挑战性更大,因此容易导致跟踪效果不佳。针对不同的应用环境,结合具体不同军事装备的特点,研究相对精确和鲁棒并且满足实时性要求的视觉目标跟踪算法,对提升装备的全天候侦察目标信息获取能力具有重要意义。     

多相关滤波自适应融合的鲁棒目标跟踪

目的 由于目标在复杂场景中可能会发生姿态变化、物体遮挡、背景干扰等情况,目标跟踪仍然是一个具有挑战性的课题。目前判别性相关滤波方法在目标跟踪问题上获得了成功而又广泛的应用。标准的相关滤波方法基于循环偏移得到大量训练样本,并利用快速傅里叶变换加速求解滤波器,使其具有很好的实时性和鲁棒性,但边界偏移带来的消极的训练样本降低了跟踪效果。空间正则化的相关滤波跟踪方法引入空间权重函数,增强目标区域的滤波器作用,在增大了目标搜索区域的同时,也增加了计算时间,而且对于目标形变不规则,背景相似的情景也会增强背景滤波器,从而导致跟踪失败。为此,基于以上问题,提出一种自适应融合多种相关滤波器的方法。方法 利用交替方向乘子法将无约束的相关滤波问题转化为有约束问题的两个子问题,在子问题中分别采用不同的相关滤波方法进行求解。首先用标准的相关滤波方法进行目标粗定位,进而用空间正则化的相关滤波跟踪方法进行再定位,实现了目标位置和滤波模板的微调,提高了跟踪效果。结果 本文算法和目前主流的一些跟踪方法在OTB-2015数据集中100个视频上,以中心坐标误差和目标框的重叠率为评判标准进行了对比实验,本文算法能较好地处理多尺度变化、姿态变化、背景干扰等问题,在CarScale、Freeman4、Girl等视频上都表现出了最好的跟踪结果;本文算法在100个视频上的平均中心坐标误差为28.55像素,平均目标框重叠率为61%,和使用人工特征的方法相比,均高于其他算法,与使用深度特征的相关滤波方法相比,平均中心坐标误差高了6像素,但平均目标框的重叠率高了4%。结论 大量的实验结果表明,在目标发生姿态变化、尺度变化等外观变化时,本文算法均具有较好的准确性和鲁棒性。     

Fuzzy spatial constraints and ranked partitioned sampling approach for multiple object tracking

While particle filters are now widely used for object tracking in videos, the case of multiple object tracking still raises a number of issues. Among them, a first, and very important, problem concerns the exponential increase of the number of particles with the number of objects to be tracked, that can make some practical applications intractable. To achieve good tracking performances, we propose to use a Partitioned Sampling method in the estimation process with an additional feature about the ordering sequence in which the objects are processed. We call it Ranked Partitioned Sampling, where the optimal order in which objects should be processed and tracked is estimated jointly with the object state. Another essential point concerns the modeling of possible interactions between objects. As another contribution, we propose to represent these interactions within a formal framework relying on fuzzy sets theory. This allows us to easily model spatial constraints between objects, in a general and formal way. The association of these two contributions was tested on typical videos exhibiting difficult situations such as partial or total occlusions, and appearance or disappearance of objects. We show the benefit of using conjointly these two contributions, in comparison to classical approaches, through multiple object tracking and articulated object tracking experiments on real video sequences. The results show that our approach provides less tracking errors than those obtained with the classical Partitioned Sampling method, without the need for increasing the number of particles.     

基于卡尔曼滤波的移动机器人运动目标跟踪

提出了一种基于卡尔曼滤波的运动目标快速跟踪算法。针对复杂背景下彩色运动目标跟踪问题,采用基于颜色特征和形状特征相结合的方法进行目标识别。利用卡尔曼滤波器的预测功能,预测运动目标在下一帧中的位置,将图像全局搜索问题转换为局部搜索,提高了系统的实时性。实验结果表明:该算法满足移动机器人运动控制的实时性要求,实现了对运动目标的快速跟踪。     

Segmenting and tracking multiple objects under occlusion using multi-label graph cut

This paper proposes a new method to segment and track multiple objects through occlusion by integrating spatial-color Gaussian mixture model (SCGMM) into an energy minimization framework. When occlusion does not occur, a SCGMM is learned for each object. When the objects are subject to occlusion, energy minimization is used to segment the objects from occlusion. To make the learned SCGMMs suitable for the segmentation of the current occlusion, a displacing procedure is utilized to adapt the SCGMMs to the spatial variations. A multi-label energy function is formulated building on the displaced SCGMMs and then minimized using the multi-label graph cut algorithm, thus leading to both the segmentation and tracking results of the objects with occlusion. Experimental validation of the proposed method is performed and presented on several video sequences.     

特征融合与视觉目标跟踪 *

针对跟踪过程中各类图像特征分离背景和目标能力的变化 ,提出一种基于增量判别分析的特征融合算法。该算法首先计算各特征图像的似然图 ,然后通过增量判别分析计算各特征分类性能 ,得到相应权重 ,并在此基础上求取融合似然图 ,通过粒子滤波算法确定待跟踪目标状态。通过对可见光及红外成像视频序列的仿真表明,该算法对环境光照变化、视角变化以及局部遮挡等均具有一定的鲁棒性。     

跟踪遮挡目标的一种鲁棒算法

为了解决在跟踪目标过程中的遮挡问题,引入Kalman滤波器为Mean Shift跟踪算法选择初始点,在跟踪稳定的情况下进行模型更新以消除由于目标缓慢变化而产生的累积误差对跟踪结果的影响。根据Kalman滤波器残差的大小判定是否发生遮挡,遮拦检测算法对目标进行分块检测从而把遮挡分为部分遮挡和完全遮挡两种情况,并对两种情况进行区别讨论：对部分遮挡情况不做特殊处理;对完全遮挡情况,结合目标的运动方向提出6点搜索策略来找回目标。实验表明,该算法能很好地解决跟踪运动目标过程中目标的遮挡问题。     

动态背景下运动目标检测与跟踪研究

主要研究动态背景下的运动目标检测和跟踪问题。背景补偿差分法是一种常用的动态背景下运动目标检测算法,但检测到的目标轮廓要比其真实轮廓大,检测结果不准确且算法复杂度较高。主动轮廓模型在图像分割和目标提取过程中具有拓扑结构变化灵活性,对数值计算方案的设计更加方便、有效,据此提出一种基于改进C-V模型和卡尔曼滤波的算法,用来检测和跟踪动态背景下的运动目标。提出的算法利用C-V模型曲线演化检测和跟踪目标,使C-V模型在目标的边缘处收敛。结合卡尔曼滤波预测运动目标下一帧位置,从而实现对运动目标轮廓的跟踪。实验结果表明,该方法可以对动态背景下运动目标进行精确的检测与跟踪。     

A robust optical/inertial data fusion system for motion tracking of the robot manipulator

We present an optical/inertial data fusion system for motion tracking of the robot manipulator, which is proved to be more robust and accurate than a normal optical tracking system（OTS）. By data fusion with an inertial measurement unit（IMU）, both robustness and accuracy of OTS are improved. The Kalman filter is used in data fusion. The error distribution of OTS pro-vides an important reference on the estimation of measurement noise using the Kalman filter. With a proper setup of the system and an effective method of coordinate frame synchronization, the results of experiments show a significant improvement in terms of robustness and position accuracy.     

基于相关滤波器的长时视觉目标跟踪方法

为解决相关滤波器（CF）在跟踪快速运动目标时存在跟踪失败的问题,提出一种结合了核相关滤波（KCF）跟踪器和基于光流法的检测器的长时核相关滤波（LKCF）跟踪算法。首先,使用跟踪器跟踪目标,并计算所得跟踪目标的峰值响应强度（PSR）;然后,通过比较峰值响应强度（PSR）与经验阈值大小判断目标是否跟踪丢失,当目标跟踪丢失时,在上一帧所得目标附近运用光流法检测运动目标,得到目标在当前帧中的粗略位置;最后,在此粗略位置处再次运用跟踪器得到精确位置。与核相关滤波（KCF）、跟踪-学习-检测（TLD）、压缩跟踪（CT）、时空上下文（STC）等4种跟踪算法进行对比实验,实验结果表明,所提算法在距离精确度和成功率上都表现最优,且分别比核相关滤波（KCF）跟踪算法高6.2个百分点和5.1个百分点,表明所提算法对跟踪快速运动目标有很强的适应能力。     

利用视觉显著性和粒子滤波的运动目标跟踪

针对运动目标跟踪问题,提出一种利用视觉显著性和粒子滤波的目标跟踪算法.借鉴人类视觉注意机制的研究成果,根据目标的颜色、亮度和运动等特征形成目标的视觉显著性特征,与目标的颜色分布模型一起作为目标的特征表示模型,利用粒子滤波进行目标跟踪.该算法能够克服利用单一颜色特征所带来的跟踪不稳定问题,并能有效解决由于目标形变、光照变化以及目标和背景颜色分布相似而产生的跟踪困难问题,具有较强的鲁棒性.在多个视频序列中进行实验,并给出相应的实验结果和分析.实验结果表明,该算法用于实现运动目标跟踪是正确有效的.     

I-VITAL: Information aided visual tracking with adversarial learning

With the advent of convolutional neural networks (CNN), MDNet and the Siamese trackers posed tracking as supervised learning. They model an object’s presence using classification (foreground and background) and location using regression. For the first time, we have brought probability distribution into the CNN framework for tracking. We have selected “Information maximization Generative Adversarial Network (InfoGAN)” to couple the target and background classes with two unique Gaussian distributions. This paper highlights the use of InfoGAN in information extraction & feedback to improve the tracking framework. Specifically, the novel features proposed in this tracking framework are (i) Coupling of unique probability distributions to target and background classes and (ii) Unsupervised tracker status (success/ failure) identification and correction through information feedback. We demonstrated the efficacy of the proposed I-VITAL tracker in visual tracking with experimental comparisons on well-known data sets such as GOT10K, VOT2020, and OTB-2015. Compared with base works, the proposed tracker has improved performance in locating the object of interest.     

A novel strong tracking finite-difference extended Kalman filter for nonlinear eye tracking

Non-intrusive methods for eye tracking are important for many applications of vision-based human computer interaction. However, due to the high nonlinearity of eye motion, how to ensure the robustness of external interference and accuracy of eye tracking poses the primary obstacle to the integration of eye movements into todays’s interfaces. In this paper, we present a strong tracking finite-difference extended Kalman filter algorithm, aiming to overcome the difficulty in modeling nonlinear eye tracking. In filtering calculation, strong tracking factor is introduced to modify a priori covariance matrix and improve the accuracy of the filter. The filter uses finite-difference method to calculate partial derivatives of nonlinear functions for eye tracking. The latest experimental results show the validity of our method for eye tracking under realistic conditions. Supported by the National Natural Science Foundation of China (Grant No. 60572027), the Outstanding Young Researchers Foundation of Sichuan Province (Grant No. 03ZQ026-033), the Program for New Century Excellent Talents in University of China (Grant No. NCET-05-0794), and the Young Teacher Foundation of Mechanical School (Grant No. MYF0806)