Research Article

Online Detection of Abnormal Events in Video Streams

Figure 3

Offline and two online abnormal event detection strategies based on one-class SVM. (a) Strategy offline. The training data are learnt as one batch offline. (b) Strategy 1. The dictionary is fixed when all the training data are learnt. (c) Strategy 2. The dictionary continues being updated through the testing period.
(a) Strategy offline
(b) Strategy 1
(c) Strategy 2