Configuring the parameters
To create the Line crossing detector, do the following:
- Create the required detector and specify its parameters (see Configuring detectors and their sub-detectors).
- 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:
| Parameter | Value | Description |
|---|
| Other |
| Enable | Yes | The detector is enabled by default. To disable the detector, select the No value |
| No |
| Name | Line crossing | Enter the detector name or leave the default name |
| Type | Line crossing | Name of the detector type (non-editable field) |
| Advanced settings |
| X-axis offset | 15 | Specify the X-axis and Y-axis offsets as a percentage of the track area to receive events from the specified area. The values must be in the range [1, 40] |
| Y-axis offset | 10 |
| Basic settings |
| Maximum object height | 100 | Specify the maximum object height as a percentage of the frame size for the detector to generate an event. The value must be in the range [0.05, 100] The values of the maximum object height must be equal in the settings of the Object tracker and Line crossing. |
|
| Maximum object speed | 500 | Specify the maximum object speed per second for the detector to generate an event. The value must be in the range [0, 500] - In Axxon One, speed is a conditional value that is calculated using values of different dimensions. The speed calculation algorithm takes into account both the frame width and its height.
- For a visual understanding of the speed values, we recommend specifying the speed when searching the archive (see Configuring minimum and maximum object speed).
|
|
| Maximum object width | 100 | Specify the maximum object width as a percentage of the frame size for the detector to generate an event. The value must be in the range [0.05, 100] The values of the maximum object width must be equal in the settings of the Object tracker and Line crossing. |
|
| Minimum object height | 0.1 | Specify the minimum object height as a percentage of the frame size for the detector to generate an event. The value must be in the range [0.05, 100] The values of the minimum object height must be equal in the settings of the Object tracker and Line crossing. |
|
| Minimum object speed | 0 | Specify the minimum object speed per second for the detector to generate an event. The value must be in the range [0, 500] - In Axxon One, speed is a conditional value that is calculated using values of different dimensions. The speed calculation algorithm takes into account both the frame width and its height.
- For a visual understanding of the speed values, we recommend specifying the speed when searching the archive (see Configuring minimum and maximum object speed).
|
|
| Minimum object width | 0.1 | Specify the minimum object width as a percentage of the frame size for the detector to generate an event. The value must be in the range [0.05, 100] The values of the minimum object width must be equal in the settings of the Object tracker and Line crossing. |
|
| Object class | All classes | Select the object class that must generate an event. The default value is All classes - When you create the Line crossing detector as a child object of the Object tracker and select the Person value, there won't be any events if the tracker detects the movement of several people nearby.
- When you create the Line crossing detector as a child object of the Category: Face and Category: Vehicle detectors, the Object class parameter must have the All classes value.
|
|
| Vehicle |
| Person |
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:
- In the preview window:
- Specify the end points of the line
:
- 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 |
- 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.
- You must select at least one direction for detection.
- An unmonitored direction of object movement is indicated by a dimmed arrow.
|
- 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).- 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.
- 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.
- Click the Apply button. Click the Cancel button to cancel the changes.
Configuration of the Line crossing detector is complete.