Abnormal Event Detection in a Surveillance Scene Using Convolutional Neural Network

Automatic abnormal event detection in a surveillance scene is very significant because of more consciousness about public safety. Because of usefulness and complexity, currently, it is an open research area. In this manuscript, the authors have proposed a novel convolutional neural network (CNN) model to detect an abnormal event in a surveillance scene. In this work, CNN is used in two ways. Firstly, it is used for both feature extraction and classification. In a second way, CNN is used for feature extraction, and support vector machine (SVM) is used for classification. Without any pre-processing, the proposed model gives better results compared to state-of-the-art methods. Experiments are carried out on four different publicly available benchmark datasets and one combined dataset, which contains all images of four datasets. The performance is measured by accuracy and area under the ROC (receiver operating characteristic) curve (AUC). The experimental results determine the efficacy of the proposed model.

Video Abnormal Event Detection Based on One-Class Neural Network

Video abnormal event detection is a challenging problem in pattern recognition field. Existing methods usually design the two steps of video feature extraction and anomaly detection model establishment independently, which leads to the failure to achieve the optimal result. As a remedy, a method based on one-class neural network (ONN) is designed for video anomaly detection. The proposed method combines the layer-by-layer data representation capabilities of the autoencoder and good classification capabilities of ONN. The features of the hidden layer are constructed for the specific task of anomaly detection, thereby obtaining a hyperplane to separate all normal samples from abnormal ones. Experimental results show that the proposed method achieves 94.9% frame-level AUC and 94.5% frame-level AUC on the PED1 subset and PED2 subset from the USCD dataset, respectively. In addition, it achieves 80 correct event detections on the Subway dataset. The results confirm the wide applicability and good performance of the proposed method in industrial and urban environments.

Abnormal Event Detection in Videos Based on Deep Neural Networks

Abnormal event detection has attracted widespread attention due to its importance in video surveillance scenarios. The lack of abnormally labeled samples makes this problem more difficult to solve. A partially supervised learning method only using normal samples to train the detection model for video abnormal event detection and location is proposed. Assuming that the distribution of all normal samples complies to the Gaussian distribution, the abnormal sample will appear with a lower probability in this Gaussian distribution. The method is developed based on the variational autoencoder (VAE), through end-to-end deep learning technology, which constrains the hidden layer representation of the normal sample to a Gaussian distribution. Given the test sample, its hidden layer representation is obtained through the variational autoencoder, which represents the probability of belonging to the Gaussian distribution. It is judged abnormal or not according to the detection threshold. Based on two publicly available datasets, i.e., UCSD dataset and Avenue dataset, the experimental are conducted. The results show that the proposed method achieves 92.3% and 82.1% frame-level AUC at a speed of 571 frames per second on average, which demonstrate the effectiveness and efficiency of our framework compared with other state-of-the-art approaches.