Configuring Line crossing

Configuring the parameters

To create the Line crossing detector, do the following:

1. Create the required detector and specify its parameters (see Configuring detectors and their sub-detectors).
2. Below the created detector, click Create… → Line crossing.

By default, the detector is enabled and set to generate events when an object crosses a virtual line.

If necessary, you can change the detector parameters. The list of parameters is given in the table:

By default, the entire frame is a detection area. If necessary, in the preview window, you can set one or more skip areas (see Configuring a skip area).

To save the parameters of the detector, click the Apply  button. To cancel the changes, click the Cancel  button.

Configuring a virtual line

To configure a virtual line, do the following:

1. In the preview window:
   
   1. Specify the end points of the line :
      
      

      Note

      • The end points are connected by a two-color dashed line. The directions of object movement through the line are indicated by dotted arrows.
      • For convenience of configuration, you can "freeze" the frame. Click the  button. To cancel the action, click this button again.
      • To hide the virtual line, click the button. To cancel the action, click this button again.

      Action	Result
      Hover the cursor over the end point and, holding down the left mouse button, move the mouse	Moving the end point of a line
      Hover the cursor over the line and, holding down the left mouse button, move the mouse	Moving the line

   2. By default, both directions of object movement through the line are detected. To stop the detection in the required direction, click the button corresponding to this direction.
      

      Attention!

      • You must select at least one direction for detection.
      • An unmonitored direction of object movement is indicated by a dimmed arrow.
        
2. In the frame, there can be situations when one and the same object frequently moves near the virtual line, which can cause the generation of excessive events. In this situation, we recommend specifying the area of the object track that completely crosses the line to receive an event from the detector. For this, in the detector parameters, specify the X-axis and Y-axis offsets as a percentage of the track area width and height.
   Configuration of the X-axis and Y-axis offsets depends on the Camera position parameter of the parent detector below which the Line crossing detector is created. For example, Neural tracker has the Camera position parameter (see Configuring the Neural tracker).
   1. The Ceiling camera position:
      For example, the green rectangle is the object track. If the X-axis and Y-axis offsets are set to 25%, an event is generated only if the red rectangle completely crosses the line.
      
   2. The Wall camera position:
      For example, the green rectangle is the object track. If the X-axis offset is set to 30%, an event is generated only if the red segment completely crosses the line.
      
      
3. Click the Apply button. Click the Cancel button to cancel the changes.

Configuration of the Line crossing detector is complete.