Real-time crowd behavior recognition in surveillance videos based on deep learning methods

Automatic video surveillance in public crowded places has been an active research area for security purposes. Traditional approaches try to solve the crowd behavior recognition task using a sequential two-stage pipeline as low-level feature extraction and classification. Lately, deep learning has shown promising results in comparison to traditional methods by extracting high-level representation and solving the problem in an end-to-end pipeline. In this paper, we investigate a deep architecture for crowd event recognition to detect seven behavior categories in PETS2009 event recognition dataset. More especially, we apply an integrated handcrafted and Conv-LSTM-AE method with optical flow images as input to extract a high-level representation of data and conduct classification. After achieving a latent representation of input optical flow image sequences in the bottleneck of autoencoder(AE), the architecture is split into two separate branches, one as AE decoder and the other as the classifier. The proposed architecture is jointly trained for representation and classification by defining two different losses. The experimental results in comparison to the state-of-the-art methods demonstrate that our algorithm can be promising for real-time event recognition and achieves a better performance in calculated metrics.