VCA - Directional Crossing
The directional crossing rule is designed to reduce false alarms common with simple line crossing use cases. Directional Crossing is designed for use with a zone rather than a line, and adds a number of additional checks for an object as it enters as well as exits that zone.
For an object to trigger the Directional Crossing rule it must:
Enter the zone travelling in a direction that falls within the acceptance angle.
Be classified as one of the specified object classes.
Exit that zone travelling in a direction that falls within the acceptance angle.
Configure the direction and acceptance angle by moving the arrows on the direction control widget. The primary direction is indicated by the large central arrow. The acceptance angle is the angle between the two smaller arrows.
The following image illustrates how the white car, moving in the configured direction, triggers the rule whereas the other objects do not.
Graphical View
Form View
Configuration
Property | Description | Default Value |
|---|---|---|
Name | A user-specified name for this rule | “Directional #” |
Can Trigger Actions | Specifies whether events generated by this rule trigger actions | Active |
Zone | The zone this rule is associated with | None |
Angle | Primary direction angle, 0 - 359. 0 references up. | 0 |
Acceptance | Allowed variance each side of primary direction that will still trigger rule | 0 |
Classes | The object classes allowed to trigger an alert | None |