Configuring the perspective for intrusion detection scenarios - KiwiVision™ 4.7.1 | Security Center 5.11.2.0

To help the analytics detect people at varying distances, you must configure the perspective of the scene, including the height of near and far objects.

What you should know

Use the white grid as a visual reference for how the perspective of the scene is interpreted. This grid changes according to the size and placement of the near and far objects, and should match the ground plane.

The white grid can be controlled by the Near object (blue) and the Far Object (yellow) controls. For proper configuration, you need to match the size of these controls with the size of the target object in the field near and far from the camera respectively.

NOTE: Depending on which scenario type you are configuring, some settings might be unavailable or hidden if Advanced mode is disabled.

1. From the Config Tool home page, open the Video task.
2. From the area view, select a camera that you applied an analytics scenario to.
3. Click Video analytics > Security monitoring, and then click the scenario you want to configure.
4. Click the Perspective tab.
   
5. Use one person in the video as a size reference to configure the near and far objects:
   1. When the person is near to the camera, click and drag the Near object over the person in the video.
   2. Adjust the Near object to match the height of the person by clicking and dragging the white dot on the object.
   3. Repeat the previous substeps using the Far object when the same person is far from the camera.
6. In the Perspective section, configure the following settings as required:
   NOTE: Changing the block size affects the size of the blocks displayed when you enable the Show movement grid option in the area configuration.

   Block size

   The size of analysis units relative to the specified object or person size in the image. If you set a low value, the required computing power increases, but the distinction between different object sizes in the image is more accurate.

   Min. block size

   The minimum size of analysis units relative to the height or width of the video, depending on which measurement is shorter.

   Object height

   The real-life height of near and far objects that you want to monitor. The default setting is 1.75 m (5.7 ft), the average height of a person.

   Tip: Ensure that the Object height defined in the Perspective section matches the height represented by the near and far objects in the video.

   Scene depth

   The scene depth distance in the view direction of the camera. The scale represents the size of an average person.

   Low block resolution

   When this option is enabled, the accuracy of motion detection per block is reduced. The required computing power is also reduced.

7. Click Apply.