结合张量特征和孪生支持向量机的群体行为识别

给出一种结合张量特征和孪生支持向量机的群体行为识别算法，以提高对视频中群体行为识别的准确率.首先通过群成员关节点骨架的姿态结构信息和群成员的社会网络信息描述群体在每一帧中的行为，并采用张量形式表示；然后使用多路非线性特征映射分解张量核，并利用粒子群优化张量核孪生支持向量机的模型参数；最后结合张量特征和孪生支持向量机实现视频中的群体行为识别.CAD2数据集和自建数据集上的实验结果表明，张量特征能够有效地表示群体行为，相比经典算法，所提算法能有效提高群体行为识别的准确率. 

Group Activity Recognition Based on Tensor Features and Twin Support Vector Machines

To improve the accuracy of group activity recognition in video, a group activity recognition algorithm was proposed based on tensor feature and twin support vector machine. Firstly, the activity of group in each frame was described by combining the posture structure information in the joint skeleton of the group members and the social network information of the group. The tensor form was used to represent the features of group activity. Then, the tensor kernel was decomposed by using multi-channel nonlinear feature mapping and the model parameters of the tensor kernel twin support vector machine were optimized by using the particle swarm optimization method. Finally, the group activity recognition in video was realized by combining tensor features and twin support vector machine. Experiments performed on the CAD2 dataset and the self-built dataset show that the tensor feature can effectively represent the group activity. Compared with the existing approach, the proposed algorithm can effectively improve the accuracy of the group activity recognition.