careplix-scan-sdk

Careplix Scan SDK for Web Browser Environment to generate Raw Scan Data.

Installation

# with npm
npm install careplix-scan-sdk

# with yarn
yarn add careplix-scan-sdk

//import Face Scan module
import * as facescan from "careplix-scan-sdk/facescan";

//import Finger Scan module
import * as fingerscan from "careplix-scan-sdk/fingerscan";

Usage

Include the following html elements in the Scan Page.

<div style="height: 100vh; position: relative;">
  <video id="videoInput" style="position: fixed; right: 1rem; top: 1rem; height: 1px; width: 1px;" autoplay muted playsinline></video>
  <canvas id="canvasOutput" style="width: 100%; height: 100%; transform: scaleX(-1);"></canvas>
</div>

Face Scan

// Initialize the Callbacks
facescan.onFrame(({ type, message, progress, timeElapsed, isLiteMode }) => {
  // Save each frame data
});
facescan.onError((err) => {
  // On any error this callback will be called
});
facescan.onScanFinish(({ raw_intensity, ppg_time, average_fps }) => {
  // Call our Cloud APIs with the given parameters
});

// Start Scan Process
facescan
  .startScan({})
  .then(() => {
    console.log("Scan Started");
  })
  .catch((err) => {
    console.log("Scan Failed");
    console.error(err);
  });

Note: If you're using React, please consider the following approach...

// use Ref for video & canvas elements
const videoRef = useRef();
const canvasRef = useRef();

React.useEffect(() => {
  // intialize all the callbacks like onFrame, onScanFinish, onError etc.
  ...

  // Start Scan Process
  facescan.startScan({ canvasElement: canvasRef.current, videoElement: videoRef.current });

  return () => {
    // be sure to cancel the ongoing scan in cleanup function
    facescan.stopScan();
  };
}, []);

onFrame()

During Scan you recieve data from every processed frame through this callback.

Property Name	Type	Description
type	string	Type of the frame. Which can be either "error" or "calibration" or "scan"
message	string	Hint for user to correct the position of their face on the screen
progress	number	Progress percentage of the scan
timeElapsed	number	Time Elapsed in ms
isLiteMode	boolean	true when the SDK switches to Lite-Mode

onError()

If any error occurs during Scan, this callback will be called with the Error object.

Error Message	Cause/Reason
Please check your internet connection & try again.	SDK failed to download neccessary files for AI scan.
No suitable subject detected. If the issue persists, consider adjusting the framing or removing any obstructions from the view.	No human face detected for a certain duration during scan-time.

More Errors...

onScanFinish()

When the scan is finished successfully, this callback will be called with raw data, which will be needed for the API call.

Property Name	Type	Description
raw_intensity	array	Raw Scan Data
ppg_time	array	Raw Scan Data
average_fps	number	Average FPS During Scan

startScan()

This function call starts the Scan.

Parameter	Type	Default	Description
scanDuration	number	60	Duration of Scan phase in sec (30-120 in multiples of 5)
livelinessDetectionDuration	number	50	Duration after which liveliness is checked
models_path	string	CarePlix CDN	Path of the models directory, only if model files are self-hosted
videoElement	HTMLVideoElement		Ref (React) or DOMElement refering to video element
canvasElement	HTMLCanvasElement		Ref (React) or DOMElement refering to canvas element

stopScan()

This function call stops the Scan.

LiteMode

During Calibration time we try to detect if the device has enough processing resource available to run the Face Detection continuously. If for any reason, the device does not have enough resources available, we then start the Scan in Lite Mode. In Lite Mode, we detect the face periodically and continue with the Scanning Process.

Finger Scan

// Initialize the Callbacks
fingerscan.onFrame(({ type, message, progress, timeElapsed }) => {
  // Save each frame data
});
fingerscan.onError((err) => {
  // On any error this callback will be called
});
fingerscan.onScanFinish(({ raw_intensity, ppg_time, average_fps }) => {
  // Call our Cloud APIs with the given parameters
});

// Start Scan Process
fingerscan
  .startScan({})
  .then(() => {
    console.log("Scan Started");
  })
  .catch((err) => {
    console.log("Scan Failed");
    console.error(err);
  });

Note: If you're using React, please consider the following approach...

// use Ref for video & canvas elements
const videoRef = useRef();
const canvasRef = useRef();

React.useEffect(() => {
  // intialize all the callbacks like onFrame, onScanFinish, onError etc.
  ...

  // Start Scan Process
  fingerscan.startScan({ canvasElement: canvasRef.current, videoElement: videoRef.current });

  return () => {
    // be sure to cancel the ongoing scan in cleanup function
    fingerscan.stopScan();
  };
}, []);

onFrame()

During Scan you recieve data from every processed frame through this callback.

Property Name	Type	Description
type	string	Type of the frame. Which can be either "error" or "calibration" or "scan"
message	string	Hint for user to correct the position of their finger on the back camera
progress	number	Progress percentage of the scan
timeElapsed	number	Time Elapsed in ms

onError()

If any error occurs during Scan, this callback will be called with the Error object.

Error Message	Cause/Reason
Flash could not be acquired.	(Non-Severe) This error will not Cancel the Scan. This error will be logged in console, when device flashlight isn't accessible via the SDK or Browser.

More Errors...

onScanFinish()

When the scan is finished successfully, this callback will be called with raw data, which will be needed for the API call.

Property Name	Type	Description
raw_intensity	array	Raw Scan Data
ppg_time	array	Raw Scan Data
average_fps	number	Average FPS During Scan

startScan()

This function call starts the Scan.

Parameter	Type	Default	Description
scanDuration	number	60	Duration of Scan phase in sec (10-120 in multiples of 5)
videoElement	HTMLVideoElement		Ref (React) or DOMElement refering to video element
canvasElement	HTMLCanvasElement		Ref (React) or DOMElement refering to canvas element

stopScan()

This function call stops the Scan.

Errors

Following are some Errors which are common to both Finger/Face Scan SDK

Error Message	Cause/Reason
We are not able to access the Camera. Please try again.	SDK is unable to get access to camera, either browser permission is disabled, or device camera is disabled, or hardware camera is not available.
Sorry we're unable to compute the signal. Please try again.	SDK failed to perform some logical operation during the scan.
App functionality disabled in the Background. Keep it in the Foreground for proper operation.	App is moved to background, maybe due to a phone-call or other reasons.

Capture image during scan

function captureImage() {
  let canvas = document.getElementById("canvasOutput");
  let dataURL = canvas.toDataURL("image/png");

  process(dataURL);
  /*
      with the dataURL i.e. "data:image/png;base64,*****" you can do the following things...
      1. Save as PNG image file, then upload to backend.
      2. Send the dataURL to the backend, then save it as file in server.
      3. Send & Save the dataURL as-is.
    */
}