Protobject Framework Protobject Framework

The PresenceSensor Component

The PresenceSensor component provides functionalities to monitor presence using webcam video.

Setting Baseline and Starting Monitoring#

Initialize the PresenceSensor component and set the baseline for presence monitoring. You can specify an optional frequency (in milliseconds) and an optional camera ID.

Protobject.PresenceSensor.setBaselineAndStartMonitoring(200, 0); //200 is the frequency of detection; 0 is the webcam id

Setting New Baseline#

Set a new baseline for presence monitoring.

Protobject.PresenceSensor.setNewBaseline();

Handling Data Callback#

Register a callback function to handle data when similarity changes.


Protobject.PresenceSensor.onData((similarity) => {
  console.log("Image similarity:" + similarity);
});

The similarity value ranges from 0 to 1, where:

  • A value close to 1 (similarity > 0.8) indicates that no presence is detected.
  • A value far from 1 (similarity < 0.8) suggests that something is in the field of vision of the camera.

Showing Video Preview#

To enable the display of the video stream, call the showPreview method, specifying the dimensions and position of the canvas.

Protobject.PresenceSensor.showPreview({ top: 50, left: 50, width: 640, height: 480 });

Hiding Video Preview#

To hide the video preview, use the hidePreview method.

Protobject.PresenceSensor.hidePreview();