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();