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Page 26 Xu et al. J Surveill Secur Saf 2020;1:16-33 I http://dx.doi.org/10.20517/jsss.2020.04

Table 1. Number of manual statistical samples of regional invasive behavior
V1 V2 V3 V4 V5 V6 V7 V8 V9 V10 Total
Abnormal 14 8 26 12 17 8 8 5 18 8 124
Normal 3 8 0 5 5 3 3 0 3 3 33

Table 2. Number of manual statistical samples of trailing behavior
F1 F2 F3 F4 F5 F6 F7 F8 F9 F10 Total
Abnormal 6 8 14 11 8 3 2 3 8 5 68
Normal 3 5 5 6 2 3 0 3 0 3 30

Table 3. Number of manual statistical samples of defamation behavior
T1 T2 T3 T4 T5 T6 T7 T8 T9 T10 Total
Abnormal 8 6 11 3 2 5 8 9 6 12 70
Normal 6 2 5 0 2 3 5 5 3 2 33

Figure 8. Identification of illegal intrusion crimes

In the detection of regional intrusion behavior, the algorithm does not use actual coordinates, but directly
judges according to pixel coordinates. Therefore, there is no difference between the algorithm and the
traditional algorithm in the abnormal behavior analysis stage. However, because the algorithm in this
paper is better than the traditional algorithm in the target detection and target tracking stage, the false
negative rate of the algorithm is greatly reduced, and finally higher accuracy is achieved. For the analysis
of the video with false positives, it is easy to have false positives in the following cases: Pedestrians walk
outside the edge of the surveillance area, and the feet do not enter the surveillance area but are closer to the
boundary of the surveillance area, as shown in Figure 8.

One key to detecting trailing behavior is the setting of the relative distance and relative distance threshold
between two pedestrians. The traditional algorithm is processed based on the pixel coordinate trajectory,
thus the relative distance and the distance threshold can only be calculated by the number of pixel points,
which is only an estimated value and is not accurate. However, the proposed algorithm is based on the
actual coordinate trajectory, and the actual distance between the targets can be calculated, which is used
as the distance threshold. In the test, the distance threshold of the algorithm was T = 1000 cm, and the
d
distance threshold of the traditional algorithm was T = 100 pixels, as shown in Figure 9.
d
Awkward behavior is a relatively complex behavior that requires not only the calculation of the speed of
pedestrian movement, but also the calculation of the angle of pedestrian movement. While the traditional
algorithm is based on the pixel coordinate trajectory, the proposed algorithm is based on the actual
coordinate trajectory [Figure 10].