Measurement preparation

After successfully installing, initializing and optionally configuring the SDK, your app should be ready to start the video measurement.

Before starting the measurement, the user should be instructed to keep a stable position without talking and changing the facial expression.

Initial conditions

After initialization, the SDK will start to analyze the video stream from the camera.

In order for the measurement to begin, the user needs to locate their face in the middle of the screen, in good lighting conditions. The embedded user interface displays face positioning hints, but you can also use the GetFaceState() and GetNormalizedFaceBbox() methods to check the current face position.


import 'package:shenai_sdk/shenai_sdk.dart';
 
// Get the current face state
final faceState = await ShenaiSdk.getFaceState();
 
switch (faceState) {
case FaceState.ok:
print("Face detected and centered");
break;
case FaceState.notCentered:
print("Face detected but not centered");
break;
case FaceState.tooClose:
print("Face is too close");
break;
case FaceState.tooFar:
print("Face is too far");
break;
case FaceState.notVisible:
print("Face is not visible");
break;
case FaceState.turnedAway:
print("Face turned away");
break;
case FaceState.unknown:
print("Unknown face state");
break;
}
 
// Get the normalized bounding box of the face
final bbox = await ShenaiSdk.getNormalizedFaceBbox();
if (bbox != null) {
print("normalized face bounding box: ${bbox.x} ${bbox.y} ${bbox.width} ${bbox.height}");
}


import { getFaceState, getNormalizedFaceBbox, FaceState } from '@shenai/react-native-sdk';
 
// Get the current face state
const faceState = await getFaceState();
 
switch (faceState) {
  case FaceState.OK:
    console.log("Face detected and centered");
    break;
  case FaceState.NOT_CENTERED:
    console.log("Face detected but not centered");
    break;
  case FaceState.TOO_CLOSE:
    console.log("Face is too close");
    break;
  case FaceState.TOO_FAR:
    console.log("Face is too far");
    break;
  case FaceState.NOT_VISIBLE:
    console.log("Face is not visible");
    break;
  case FaceState.TURNED_AWAY:
    console.log("Face turned away");
    break;
  case FaceState.UNKNOWN:
    console.log("Unknown face state");
    break;
}
 
// Get the normalized bounding box of the face
const bbox = await getNormalizedFaceBbox();
if (bbox) {
  console.log("normalized face bounding box:", bbox.x, bbox.y, bbox.width, bbox.height);
}


import { ShenaiSdkCapacitor, FaceState } from "@shenai/capacitor-sdk"
 
// Get the current face state
const { value: faceState } = await ShenaiSdkCapacitor.getFaceState()
 
switch (faceState) {
  case FaceState.OK:
    console.log("Face detected and centered")
    break
  case FaceState.NOT_CENTERED:
    console.log("Face detected but not centered")
    break
  case FaceState.TOO_CLOSE:
    console.log("Face is too close")
    break
  case FaceState.TOO_FAR:
    console.log("Face is too far")
    break
  case FaceState.NOT_VISIBLE:
    console.log("Face is not visible")
    break
  case FaceState.TURNED_AWAY:
    console.log("Face turned away")
    break
  case FaceState.UNKNOWN:
    console.log("Unknown face state")
    break
}
 
// Get the normalized bounding box of the face
const bbox = await ShenaiSdkCapacitor.getNormalizedFaceBbox()
if (bbox) {
  console.log("normalized face bounding box:", bbox.x, bbox.y, bbox.width, bbox.height)
}


using Shenai.Maui;
 
// Get the current face state
var faceState = await ShenaiSdk.GetFaceStateAsync();
 
switch (faceState)
{
    case FaceState.OK:
        Console.WriteLine("Face detected and centered");
        break;
    case FaceState.NOT_CENTERED:
        Console.WriteLine("Face detected but not centered");
        break;
    case FaceState.TOO_CLOSE:
        Console.WriteLine("Face is too close");
        break;
    case FaceState.TOO_FAR:
        Console.WriteLine("Face is too far");
        break;
    case FaceState.NOT_VISIBLE:
        Console.WriteLine("Face is not visible");
        break;
    case FaceState.TURNED_AWAY:
        Console.WriteLine("Face turned away");
        break;
    case FaceState.UNKNOWN:
        Console.WriteLine("Unknown face state");
        break;
}
 
// Get the normalized bounding box of the face
var bbox = await ShenaiSdk.GetNormalizedFaceBboxAsync();
if (bbox != null)
{
    Console.WriteLine($"normalized face bounding box: {bbox.X} {bbox.Y} {bbox.Width} {bbox.Height}");
}


// Get the current face state
let faceState = ShenaiSDK.getFaceState()
 
switch faceState {
case .ok:
  print("Face detected and centered")
case .notCentered:
  print("Face detected but not centered")
case .tooClose:
  print("Face is too close")
case .tooFar:
  print("Face is too far")
case .notVisible:
  print("Face is not visible")
case .turnedAway:
  print("Face turned away")
case .unknown:
  print("Unknown face state")
}
 
// Get the normalized bounding box of the face
if let bbox = ShenaiSDK.getNormalizedFaceBbox() {
  print("normalized face bounding box: \(bbox.x) \(bbox.y) \(bbox.width) \(bbox.height)")
}


// Get the current face state
ShenAIAndroidSDK.FaceState faceState = shenaiSDKHandler.getFaceState();
 
switch (faceState) {
case OK:
System.out.println("Face detected and centered");
break;
case NOT_CENTERED:
System.out.println("Face detected but not centered");
break;
case TOO_CLOSE:
System.out.println("Face is too close");
break;
case TOO_FAR:
System.out.println("Face is too far");
break;
case NOT_VISIBLE:
System.out.println("Face is not visible");
break;
case TURNED_AWAY:
System.out.println("Face turned away");
break;
case UNKNOWN:
System.out.println("Unknown face state");
break;
}
 
// Get the normalized bounding box of the face
ShenAIAndroidSDK.NormalizedFaceBbox bbox = shenaiSDKHandler.getNormalizedFaceBbox();
if (bbox != null) {
System.out.println("normalized face bounding box: " + bbox.x + " " + bbox.y + " " + bbox.width + " " + bbox.height);
}


import { FaceState } from "@shenai/sdk";
 
// Get the current face state
const faceState = shenaiSDK.getFaceState();
 
switch (faceState) {
  case FaceState.OK:
    console.log("Face detected and centered");
    break;
  case FaceState.NOT_CENTERED:
    console.log("Face detected but not centered");
    break;
  case FaceState.TOO_CLOSE:
    console.log("Face is too close");
    break;
  case FaceState.TOO_FAR:
    console.log("Face is too far");
    break;
  case FaceState.NOT_VISIBLE:
    console.log("Face is not visible");
    break;
  case FaceState.TURNED_AWAY:
    console.log("Face turned away");
    break;
  case FaceState.UNKNOWN:
    console.log("Unknown face state");
    break;
}
 
// Get the normalized bounding box of the face
const bbox = shenaiSDK.getNormalizedFaceBbox();
 
console.log("normalized face bounding box:", bbox.x, bbox.y, bbox.width, bbox.height);