Setting up the detection zone

Setting up the detection zone is performed by setting the following parameters:

1. Zone positioning;
2. Zone direction;
3. Zone size.

Note! Vehicle detector is optimized for detecting the zones of 6 meters in length and 2 meters in width.
Setting up the detection zone is performed in the video frame with the help of a graphic tool.
If the zone is setup approximately, to scale the zone in the frame one should use a road marking or nearby objects (curbing, hatches etc.).
Note. In this case area's topographic parameters should be preliminary determined.
For zone's length accurate setup one should use cones, paint or other ways of the road marking .The distance between marks along the line should be 6 meters and zone's length should be correspondingly setup.
Note! Value of systematic errors depends on the value of zone's length errors.
Zone's width and its cross position in respect of the line's center can be varied to diminish the effect of the traffic cross overlap, moving by the next lines.
To provide the detector's algorithm efficient operation the zone size in the frame must occupy from 2 to 20 percent of the frame's area. If possible the detection zones have to be in that part of the frame, where the scale is greater (it is usually in the bottom).
Detection zone's direction must coincide with the traffic motion.
Setting up the detection zone is done in the following way:

1. Go to the Vehicle detector object settings panel (Fig. 7.7—3)

Fig. 7.7—3 Setting up the detection zone

1. Click the «Detector setting» to set up the detector zone's positioning (Fig. 7.7—3, 1)
2. «Frame selection» dialog window will open in result (Fig. 7.7—4)

Fig. 7.7—4 Frame selection for setting up the detection zone

1. Click «Select frame» to select a video frame (Fig. 7.7—4)
2. «Zone positioning setting» dialog window will open in result (Fig. 7.7—5)

Fig. 7.7—5 Zone positioning setup

1. Using the keyboard and a mouse set the zone detection parameters (Table 7.7—1).

Table 7.7—1 keys for setting the zone positioning parameters

Note. To set up the detection zone one has to use road's reference points with familiar topographic parameters.

1. Click «OK» to save the changes and close the dialog window Zone position setting (Fig. 7.7—5)
2. Click «Apply» to save the changes(Fig. 7.7—3, 2)

Zone position setup is completed.