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Visual object tracking remains a challenging task in computer vision although important progress has been made in the past decades. Particle filter (PF) is now a standard framework for solving non-linear/non-Gaussian problems, especially in visual object tracking. This study proposes an ant colony optimisation (ACO)-based iterative PF for object tracking. In the proposed method, the basic idea of ACO is used to simulate the behaviour of a particle moving toward the posterior distribution. Such idea is incorporated into the particle filtering framework in order to overcome the well-known particle impoverishment problem. An iterative unscented Kalman filter is used to design a proposal distribution for particle generation in order to generate better predicted sample states. For the likelihood model, the authors adopt the locality sensitive histogram to model the appearance of the target object, which can better handle the illumination variation during tracking. The experimental results demonstrate that the proposed tracker shows better performance than the other tracking methods.

The main purpose of visual servoing is to control the motion of a robot system based on visual information provided by one or more cameras. It is an important research topic in the robotics community. In uncalibrated visual servoing, the image Jacobian matrix estimation is of great importance to the success of visual servoing control. This paper addresses the online estimation of the total Jacobian matrix for robot visual servoing using the unscented particle filter. We first give the definition of the total Jacobian matrix and formulate the total Jacobian matrix estimation problem into Bayesian filtering framework. Then, we propose to estimate the total Jacobian matrix using the unscented particle filter. Each particle is propagated and updated using the unscented Kalman filter equations. Such an update can make full use of the image feature measurements and consequently generate more accurate estimation results. The simulation results on a 2DOF robot visual servoing platform show that the proposed method provides accurate and reliable performance in the object tracking task.

Aiming at the problem of enhancing the suggestion and decision-making ability of home automation system under the condition of less user intervention involved, an adaptive control system based on scene perception in smart home is proposed. Firstly, the scenario information is extracted from graphic data by reinforcement learning method, and then the adaptive decision model based on deep learning is constructed, a simulated system was tested based on its ability to predict the best interval present in day for lights and blinds in different rooms, operations of the home equipment is updated according to the user's behavior. Results shows that the proposed model is able to predict the best 15 minute interval in a day for lights and blinds in different rooms of a home without user intervention and user feedback could improve model prediction performance.

Visual object tracking is a challenging research task in computer vision community which has been intensively studied by researchers in the past decades. Among all of the existing methods, particle filter based methods have gained special attention due to its ability to handle highly nonlinear/non-Gaussian multi-modality models. This paper proposes a robust particle filter based tracking method based on the Langevin Monte Carlo sampling. The Langevin Monte Carlo sampling method leverages the gradient of the posterior probability distribution to draw new particles. Meanwhile, an auxiliary momentum variable is introduced to ensure that the proposed sample cannot be trapped in local mode of the posterior distribution. As for the likelihood model, we introduce the locality sensitive histogram based model to handle the severe appearance variations induced by illumination change, partial occlusion or other factors. We compare the proposed method with several popular tracking methods from qualitative and quantitative perspectives. The experimental results show that the proposed method outperforms its counterparts.

The past several decades have witnessed the successful application of sequential Monte Carlo method (or particle filter) to a variety of fields. It has grown to be a popular method in solving different kinds of nonlinear Bayesian estimation problems. This paper introduces a two-stage particle filter for nonlinear filtering problem. In the proposed particle filter, each particle will be propagated and updated through two stages. At time step $t$ , the first stage refers to using the unscented Kalman filtering equations to propagate the particles from time step $t-1$ in order to obtain the preliminary estimations. Then, at the second stage, the particles will be updated again by the iterated extended Kalman filter to yield the final updated particles. In this way, the estimation accuracy of particle filter can be improved, which is validated through simulation experiments and real-world application experiments.

Visual tracking is a fundamental research topic in computer vision community, which is of great importance in many application areas including augmented reality, traffic control, medical imaging and video editing. This paper presents an ordered over-relaxation Langevin Monte Carlo sampling (ORLMC) based tracking method within the Bayesian filtering framework, in which the traditional object state variable is augmented with an auxiliary momentum variable. At the proposal step, the proposal distribution is designed by simulation of the Hamiltonian dynamics. We first use the ordered over-relaxation method to draw the momentum variable which could suppress the random walk behavior in Gibbs sampling stage. Then, we leverage the gradient of the energy function of the posterior distribution to draw new samples with high acceptance ratio. The proposed tracking method could ensure that the tracker will not be trapped in local optimum of the state space. Experimental results show that the proposed tracking method successfully tracks the objects in different video sequences and outperforms several conventional methods.

Recent researches on visual tracking have shown significant improvement in accuracy by handling the large uncertainties induced by appearance variation and abrupt motion. Most studies concentrate on random walk based Markov chain Monte Carlo(MCMC) tracking methods which have shown inefficiency in sampling from complex and high-dimensional distributions. This paper proposes an adaptive Hamiltonian Monte Carlo sampling based tracking method within the Bayesian filtering framework. In order to suppress the random walk behavior in Gibbs sampling stage, the ordered over-relaxation method is used to draw the momentum item for the joint state variable. An adaptive step-size based scheme is used to simulate the Hamiltonian dynamics in order to reduce the simulation error and improve acceptance rate of the proposed samples. Furthermore, in designing the appearnce model, we introduce the locality sensitive histogram (LSH) to deal with appearance changes induced by illumination change. The proposed tracking method is compared with several state-of-the-art trackers using different quantitative measures: success rate and abruption capture rate. Extensive experimental results have shown its superiority to several other trackers.

Sequential Monte Carlo method (also named as particle filter) is now a standard framework for solving nonlinear/non-Gaussian problems, especially in computer vision fields. This paper proposes an ant colony optimization (ACO) based iterative particle filter for visual tracking. In the proposed tracking method, the basic idea of ACO is used to simulate the behavior of particle moving toward the posterior density. Such idea is incorporated into the particle filtering framework in order to overcome the well-known problem of particle impoverishment. We design an iterative proposal distribution for particle generation in order to generate better predicted sample states. The experimental results demonstrate that the proposed tracker shows better performance than the other trackers.