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Measurement Modes ​

The SDK supports the following measurements modes:

Once a face session is created, the application can receive notification on the session state transitions, the allowed vital signs for the session and set the user information.

Face Measurement ​

A face measurement is performed by creating a face session and facing the front (selfie) camera to the user's face.

Dart
try {
    LicenseDetails licenseDetails = LicenseDetails("<ENTER_YOUR_LICENSE_KEY>");
    Session? session = await FaceSessionBuilder()
        .withImageDataListener(this)
        .withVitalSignsListener(this)
        .withSessionInfoListener(this)
        .build(licenseDetails);
} on HealthMonitorException catch(e) {
    print("Received Error. Domain: ${e.domain} Code: ${e.code}");
}

After creating the face session the application can receive the camera images, create camera preview, set the [device orientation] and enforce the image validity according to the measurement guidance.

Face Measurement Using the Back Camera ​

The SDK now supports taking face measurements using the back camera. It is recommended to set .withStrictMeasurementGuidance(false) when using the back camera to ensure accurate face distance calculations and avoid invalid image issues.

Note

This option is for evaluation and integration purposes only. Please contact our support if you would like to use this option in production.

Dart
try {
    LicenseDetails licenseDetails = LicenseDetails("<ENTER_YOUR_LICENSE_KEY>");
    Session? session = await FaceSessionBuilder()
        .withCameraLocation(CameraLocation.back)
        .withImageDataListener(this)
        .withVitalSignsListener(this)
        .withSessionInfoListener(this)
        .build(licenseDetails);
} on HealthMonitorException catch(e) {
    print("Received Error. Domain: ${e.domain} Code: ${e.code}");
}

Polar Measurement ​

A Polar measurement is conducted by creating a polar session and pairing the device with the Polar Verity Sense sensor.

Dart
try {
    LicenseDetails licenseDetails = LicenseDetails("<ENTER_YOUR_LICENSE_KEY>");
    String deviceId = "<ENTER_POLAR_DEVICE_ID>"
    Session? session = await PolarSessionBuilder(deviceId)
        .withVitalSignsListener(this)
        .withSessionInfoListener(this)
        .withPPGDeviceInfoListener(this)
        .build(licenseDetails);
} on HealthMonitorException catch(e) {
    print("Received Error. Domain: ${e.domain} Code: ${e.code}");
}

The user must wear the Verity Sense device on the forearm and follow the best practices for taking a measurement using external devices.

The Polar Device ID can either be retrieved by the PPG Device Scanner or found on the Polar device as shown in the image below: img

Additional information regarding Polar Verity Sense can be found in Polar Verity Sense User Manual.