运动目标检测的红外与可见光图像融合方法

在弱可见光条件下,对同一场景监控的红外与可见光图像进行融合,使融合图像即显示红外目标,又能保留可见光图像的细节结构信息,方便观察者对场景的观察与监控。充分利用红外成像的特点,热目标与背景的温度差会使目标在红外图像中的灰度值更大。使用红外序列建立稳定的背景模型,当前帧与背景的差得到运动目标区域,然后,将目标区域内的红外目标融合到可见光图像中,达到对红外运动目标检测的目的。     

采用目标提取和NSCT的红外与可见光图像融合

针对目前红外图像和可见光图像融合中,融合图像信息量不足的问题,将目标提取和NSCT方法相结合,对其中的高频目标区域提出了基于局部信息熵的融合规则。将其与小波变换法、拉普拉斯法、NSCT法、提升方向波变换法作比较,并通过熵、标准差、相关系数等参数对融合后的图像进行定量分析。实验结果表明,该方法不但较好地提高了融合图像信息量,而且能够更加有效、准确地提取源图像中的特征,在主观视觉效果与客观评价指标上均取得了较好的融合效果。     

Fusion of color and infrared video for moving human detection

We approach the task of human silhouette extraction from color and thermal image sequences using automatic image registration. Image registration between color and thermal images is a challenging problem due to the difficulties associated with finding correspondence. However, the moving people in a static scene provide cues to address this problem. In this paper, we propose a hierarchical scheme to automatically find the correspondence between the preliminary human silhouettes extracted from synchronous color and thermal image sequences for image registration. Next, we discuss strategies for probabilistically combining cues from registered color and thermal images for improved human silhouette detection. It is shown that the proposed approach achieves good results for image registration and human silhouette extraction. Experimental results also show a comparison of various sensor fusion strategies and demonstrate the improvement in performance over non-fused cases for human silhouette extraction.     

Change detection for moving object segmentation with robust background construction under Wronskian framework

Although background subtraction techniques have been used for several years in vision systems for moving object detection, many of them fail to provide good results in presence of noise, illumination variation, non-static background, etc. A basic requirement of background subtraction scheme is the construction of a stable background model and then comparing each incoming image frame with it so as to detect moving objects. The novelty of the proposed scheme is to construct a stable background model from a given video sequence dynamically. The constructed background model is compared with different image frames of the same sequence to detect moving objects. In the proposed scheme the background model is constructed by analyzing a sequence of linearly dependent past image frames in Wronskian framework. The Wronskian based change detection model is further used to detect the changes between the constructed background scene and the considered target frame. The proposed scheme is an integration of Gaussian averaging and Wronskian change detection model. Gaussian averaging uses different modes which arise over time to capture the underlying richness of background, and it is an approach for background building by considering temporal modes. Similarly, Wronskian change detection model uses a spatial region of support in this regard. The proposed scheme relies on spatio-temporal modes arising over time to build the appropriate background model by considering both spatial and temporal modes. The results obtained by the proposed model is found to provide accurate shape of moving objects. The effectiveness of the proposed scheme is verified by comparing the results with those of some of the existing state of the art background subtraction techniques on public benchmark databases. We found that the average F-measure is significantly improved by the proposed scheme from that of the state-of-the-art techniques.     

An improved statistical approach for moving object detection in thermal video frames

In a video surveillance system, background modeling is assumed to be a fundamental technique for moving object detection. The surveillance system based on thermal video overcomes many challenges, such as background variations, varying light intensity, external illumination source, and so on. This paper presents a new method for background modeling and background subtraction. The method utilizes the combined approach of Fisher's Linear Discriminant and Relative Entropy for pixel based classification and detection of moving objects in thermal video frames. The experimental results show the higher average value of various performance indicators like Accuracy, ROC, and F-measure. In contrast, the percentage of false classification and total error is minimum and also has lesser execution time. The method outperforms when compared with the other existing methods.

     

A new thermal infrared and visible spectrum images-based pedestrian detection system

In this paper, we propose a hybrid system for pedestrian detection, in which both thermal and visible images of the same scene are used. The proposed method is achieved in two basic steps: (1) Hypotheses generation (HG) where the locations of possible pedestrians in an image are determined and (2) hypotheses verification (HV), where tests are done to check the presence of pedestrians in the generated hypotheses. HG step segments the thermal image using a modified version of OTSU thresholding technique. The segmentation results are mapped into the corresponding visible image to obtain the regions of interests (possible pedestrians). A post-processing is done on the resulting regions of interests to keep only significant ones. HV is performed using random forest as classifier and a color-based histogram of oriented gradients (HOG) together with the histograms of oriented optical flow (HOOF) as features. The proposed approach has been tested on OSU Color-Thermal, INO Video Analytics and LITIV data sets and the results justify its effectiveness.

     

一种运动目标检测优化算法

提出了一种用于图像序列中检测运动目标的优化算法。针对用于室内目标检测的差分法存在着“虚影”噪声,以及用于室外目标检测的背景估计法在对短序列进行检测时,其结果中存在“残像”噪声的问题,揭示并利用两次差分之间的相关性实现了对“虚影”的检测并将其消除,将其引入背景估计法,以消除后者存在的“残像”噪声。实验表明,该方法在目标检测中不仅消除了“虚影”和“残像”噪声,而且检测结果的完整性显著提高。     

Fusion of visible and infrared imagery for night color vision

A combined approach for fusing night-time infrared with visible imagery is presented in this paper. Night color vision is thus accomplished and the final scene has a natural day-time color appearance. Fusion is based either on non-negative matrix factorization or on a transformation that takes into consideration perceptual attributes. The final obtained color images possess a natural day-time color appearance due to the application of a color transfer technique. In this way inappropriate color mappings are avoided and the overall discrimination capabilities are enhanced. Two different data sets are employed and the experimental results establish the overall method as being efficient, compact and perceptually meaningful.     

基于混合高斯模型的运动目标检测

提出了一种新的基于HSV颜色空间的阴影检测和误判检测的自适应背景模型运动目标检测算法,并将其应用于运动物体的分割。该算法较好地解决了背景模型的提取、更新、背景扰动、外界光照变化等问题。实验结果表明了该算法的实时性、可靠性和准确性较好。     

多特征稳健主成分分析的视频运动目标分割

提出一种多特征稳健主成分分析(MFRPCA)算法,该算法融合多种视觉特征进行视频运动目标分割,分割的目的即将运动目标从静止信息中提取出来,分割的主要过程是将多特征视频矩阵分解为低秩矩阵和稀疏矩阵.矩阵分解过程是求解一个带受限条件的核范数与L2,1范数组合的最小化问题,此最小化问题可以通过增广拉格朗日乘子法(ALM)有效求解.与其他算法相比,本文算法融合了图像的颜色、边缘和纹理特征等多个特征,通过对变化检测基准数据集进行检测,本文算法获得的查全率为0.486 0和F度量为0.559 7,实验结果表明,本文算法的稳健性和可靠性均优于其他算法.     

Fusion of visible and thermal images for facial expression recognition

Most present research into facial expression recognition focuses on the visible spectrum, which is sensitive to illumination change. In this paper, we focus on integrating thermal infrared data with visible spectrum images for spontaneous facial expression recognition. First, the active appearance model AAM parameters and three defined head motion features are extracted from visible spectrum images, and several thermal statistical features are extracted from infrared (IR) images. Second, feature selection is performed using the F-test statistic. Third, Bayesian networks BNs and support vector machines SVMs are proposed for both decision-level and feature-level fusion. Experiments on the natural visible and infrared facial expression (NVIE) spontaneous database show the effectiveness of the proposed methods, and demonstrate thermal IR images’ supplementary role for visible facial expression recognition.     

一种快速的运动目标检测算法

将运动目标检测的改进方式分为三类。针对固定摄像机的视觉监控系统,提出了一种改进的高斯混合模型算法。通过对方差在高斯混合模型中的作用进行分析,省略方差更新,将方差设为固定值,均值学习率采用固定值。实验结果表明,同传统检测方法相比,改进的算法具有更好的实时性与可靠性。     

基于注意力机制的红外与可见光图像融合网络

针对现有融合方法缺乏通用性的问题,提出一种结合空间注意力和通道注意力的特征融合网络,设计一个端到端融合框架,采用两阶段的训练策略进行训练。在第一个阶段,训练一个自编码器用来提取图像的特征;在第二个阶段,使用提出的融合损失函数对融合网络进行训练。实验结果表明,该算法既能保留红外图像显著目标特征,还能在保留可见光图像细节上有很好的特性。主观和客观的实验分析验证了该算法的有效性。     

Entropy based region selection for moving object detection

This article addresses a problem of moving object detection by combining two kinds of segmentation schemes: temporal and spatial. It has been found that consideration of a global thresholding approach for temporal segmentation, where the threshold value is obtained by considering the histogram of the difference image corresponding to two frames, does not produce good result for moving object detection. This is due to the fact that the pixels in the lower end of the histogram are not identified as changed pixels (but they actually correspond to the changed regions). Hence there is an effect on object background classification. In this article, we propose a local histogram thresholding scheme to segment the difference image by dividing it into a number of small non-overlapping regions/windows and thresholding each window separately. The window/block size is determined by measuring the entropy content of it. The segmented regions from each window are combined to find the (entire) segmented image. This thresholded difference image is called the change detection mask (CDM) and represent the changed regions corresponding to the moving objects in the given image frame. The difference image is generated by considering the label information of the pixels from the spatially segmented output of two image frames. We have used a Markov Random Field (MRF) model for image modeling and the maximum a posteriori probability (MAP) estimation (for spatial segmentation) is done by a combination of simulated annealing (SA) and iterated conditional mode (ICM) algorithms. It has been observed that the entropy based adaptive window selection scheme yields better results for moving object detection with less effect on object background (mis) classification. The effectiveness of the proposed scheme is successfully tested over three video sequences.     

实时运动目标检测与跟踪平台的构建*

构建了一个基于图像采集卡的复杂环境下实时运动目标检测与跟踪的实验平台。基于此平台提出并实现了一种改进的运动目标检测算法,它融合了帧间差分法和背景差分法的优点,以适应复杂环境的变化。实验表明,该算法利用所构建的平台,对变化场景中的运动目标实施了快速有效的检测与跟踪,为智能视频技术的研究提供了一个实用的实验平台。     

Fusion of infrared and visible images using neutrosophic fuzzy sets

Fusion of infrared and visible image is a technology which combines information from two different sensors for the same scene. It also gives extremely effective information complementation, which is widely used for the monitoring systems and military fields. Due to limited field depth in an imaging device, visible images can’t identify some targets that may not be apparent due to poor lighting conditions or because that the background color is similar to the target. To deal with this problem, a simple and efficient image fusion approach of infrared and visible images is proposed to extract target’s details from infrared images and enhance the vision in order to improve the performance of monitoring systems. This method depends on maximum and minimum operations in neutrosophic fuzzy sets. Firstly, the image is transformed from its spatial domain to the neutrosophic domain which is described by three membership sets: truth membership, indeterminacy membership, and falsity membership. The indeterminacy in the input data is handled to provide a comprehensive fusion result. Finally, deneutrosophicised process is made which means that the membership values are retransformed into a normal image space. At the end of the study, experimental results are applied to evaluate the performance of this approach and compare it to the recent image fusion methods using several objective evaluation criteria. These experiments demonstrate that the proposed method achieves outstanding visual performance and excellent objective indicators.

     

DTCWT域的红外与可见光图像融合算法

针对红外与可见光图像融合存在融合图像对比度和清晰度降低、噪声干扰等问题,提出一种DTCWT域的红外与可见光图像融合算法。首先对源图像进行预增强处理;然后通过DTCWT正变换得到低频子带图像和高频子带图像;再分别利用基于直觉模糊集的融合规则融合低频子带图像,基于信息反差对比度的融合规则融合高频子带图像;最后对融合后的低频子带图像和高频子带图像进行DTCWT逆变换得到融合图像。实验结果表明,本文算法能有效提高融合图像对比度和清晰度,降低噪声干扰,客观评价指标总体优于现有算法的,运行效率也有所提升。     

红外舰船目标的自适应鲁棒检测方法

针对背景杂乱的红外舰船目标检测问题,提出了一种红外舰船目标的自动检测新算法。该方法利用红外舰船图像中目标与背景在灰度直方图上的差异,通过对拟合直方图的多项式曲线参数鲁棒求解,进而求出舰船目标的分割阈值。然后,根据红外舰船目标亮度与图像平均亮度的关系等,对求得的阈值合理性进行判断。若该阈值不合理,则将其作为阈值初值,对红外舰船图像进行自适应局部递归分割。最后,结合红外舰船目标吃水线、天空与背景的边界特征等先验知识,对分割出的背景进行剔除。实验结果表明,该方法对强杂波干扰的红外舰船目标能实现可靠的检测,具有很好的适应性和鲁棒性。     

Physical models for moving shadow and object detection in video

Current moving object detection systems typically detect shadows cast by the moving object as part of the moving object. In this paper, the problem of separating moving cast shadows from the moving objects in an outdoor environment is addressed. Unlike previous work, we present an approach that does not rely on any geometrical assumptions such as camera location and ground surface/object geometry. The approach is based on a new spatio-temporal albedo test and dichromatic reflection model and accounts for both the sun and the sky illuminations. Results are presented for several video sequences representing a variety of ground materials when the shadows are cast on different surface types. These results show that our approach is robust to widely different background and foreground materials, and illuminations.     

A unified saliency detection framework for visible and infrared images

Multimedia Tools and Applications - Conventional saliency detection algorithms usually achieve good detection performance at the cost of high computational complexity, and most of them focus on...