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This paper proposes a novel discriminative regression method, called adaptive locality preserving regression (ALPR) for classification. In particular, ALPR aims to learn a more flexible and discriminative projection that not only preserves the intrinsic structure of data, but also possesses the properties of feature selection and interpretability. To this end, we introduce a target learning technique to adaptively learn a more discriminative and flexible target matrix rather than the pre-defined strict zero-one label matrix for regression. Then, a locality preserving constraint regularized by the adaptive learned weights is further introduced to guide the projection learning, which is beneficial to learn a more discriminative projection and avoid overfitting. Moreover, we replace the conventional ‘Frobenius norm’ with the special $l_{2,1}$ norm to constrain the projection, which enables the method to adaptively select the most important features from the original high-dimensional data for feature extraction. In this way, the negative influence of the redundant features and noises residing in the original data can be greatly eliminated. Besides, the proposed method has good interpretability for features owing to the row-sparsity property of the $l_{2,1}$ norm. Extensive experiments conducted on the synthetic database with manifold structure and many real-world databases prove the effectiveness of the proposed method. [ABSTRACT FROM AUTHOR]

Abstract Designing a general motion detection method that has self-adaptive parameters remains a challenging issue in video surveillance. To address this problem, in this paper, a dual-target nonparametric background modeling (DTNBM) method is proposed. This model integrates the gray value and gradient to represent each pixel, which enhances the discriminative ability of the background model. We design a simple but effective classification rule for determining whether a pixel belongs to a motionless object or dynamic background. Moreover, DTNBM provides suitable updating strategies for the two categories of pixels. Most importantly, DTNBM utilizes a dual-target updating strategy to preserve the completeness of static objects and prevent false detections that are caused by background initialization or frequent background variations. To improve the updating effectiveness and efficiency, we combine similar and random schemes for background updating. The key features of DTNBM include nonparametric modeling and a controlling threshold adaptation process, which render our method easy to use on various scenarios. Comprehensive experiments have been conducted, and the results demonstrate that DTNBM outperforms the state-of-the-art methods in foreground detection. Highlights • A simple but effective pixel classification rule is explored to identify pixel. • A dual-target updating strategy is proposed to update background model. • A controlling threshold adaptation process is designed for diverse scenarios. • The proposed algorithm is very applicable for different applications. [ABSTRACT FROM AUTHOR]

This paper proposes a velocity learning method based on the directional Gaussian model to detect speeding events in surveillance scenarios. The proposed method is of an uncalibrated type, but yet has considered the influences of projective transformation on estimating the motion velocities in an image plane, which is convenient and feasible to use in real application. We have analyzed the theory that the velocity in the image plane varies due to the changes of the direction of the moving object with constant velocity in a real world plane. With the support of this theory, we propose to learn the velocities calculated on a certain position in different direction bins to tolerate the effect of projective transformation on velocity modeling. To facilitate the whole framework, two key issues have to be addressed. First, we have designed an improved Fisher model to optimize the direction bins, which reflect the major moving directions in a scenario. Second, we have adopted a weighted sampling strategy and surface fitting to solve the lack of sample problem during the learning process. Experiments conducted on real surveillance videos show that the proposed method can obtain competitive results compared with the state-of-the-art methods. [ABSTRACT FROM PUBLISHER]

Background modeling has played an important role in detecting the foreground for video analysis. In this paper, we presented a novel background modeling method for foreground segmentation. The innovations of the proposed method lie in the joint usage of the pixel-based adaptive segmentation method and the background updating strategy, which is performed in both pixel and object levels. Current pixel-based adaptive segmentation method only updates the background at the pixel level and does not take into account the physical changes of the object, which may result in a series of problems in foreground detection, e.g., a static or low-speed object is updated too fast or merely a partial foreground region is properly detected. To avoid these deficiencies, we used a counter to place the foreground pixels into two categories (illumination and object). The proposed method extracted a correct foreground object by controlling the updating time of the pixels belonging to an object or an illumination region respectively. Extensive experiments showed that our method is more competitive than the state-of-the-art foreground detection methods, particularly in the intermittent object motion scenario. Moreover, we also analyzed the efficiency of our method in different situations to show that the proposed method is available for real-time applications. [ABSTRACT FROM PUBLISHER]

To extract salient features from images is significant for image classification. Deformable objects suffer from the problem that a number of pixels may have varying intensities. In other words, pixels at the same positions of training samples and test samples of an object usually have different intensities, which makes it difficult to obtain salient features of images of deformable objects. In this paper, we propose a novel method to address this issue. Our method first produces new representation of original images that can enhance pixels with moderate intensities of the original images and reduces the importance of other pixels. The new representation and original image of the object are complementary in representing the object, so the integration of them is able to improve the accuracy of image classification. The image classification experiments show that the simultaneous use of the proposed novel representations and original images can obtain a much higher accuracy than the use of only the original images. In particular, the incorporation of sparse representation with the proposed method can bring surprising improvement in accuracy. The maximum improvement in the accuracy may be greater than 8%. Moreover, The proposed non-parameter weighted fusion procedure is also attractive. The code of the proposed method is available at http://www.yongxu.org/lunwen.html . [ABSTRACT FROM AUTHOR]