https://www.bioid.com/bws/uui?access_token={token}&return_url={url}}[&state={state}]

The BWS unified user interface is an implementation based on the BWS Web API and provides a user interface where the developers can redirect their users to perform various biometric tasks like verification or enrollment.

It is currently implemented on our company web server https://www.bioid.com, but more implementations may be available soon. Anyway, the source code and the required modules (jQuery, Silverlight) are free to download and can be customized as needed. A project containing the sources and modules will be available on our GitHub account.

The user interface is implemented as a single HTML5 / JavaScript page. It makes use of the HTML5 Media Capture and Streams API (nowadays supported by all current browser versions) to capture images from the webcam.

When a user opens the page, access to the camera is requested by the browser. After allowing access to the camera, the user can start the recording at any time using the buttons on top. After recording has been started the first image is automatically captured and sent to the Upload Web API. Then the application tries to detect motion in the central area in front of the camera. As soon as the motion-threshold is exceeded the next image is captured and uploaded.

The upload API at the BWS server performs a quality check of the uploaded images to decide, whether to keep the image or not. If enough images are available at the server, the application invokes the BWS liveness detection, verification, identification or enrollment web API (as prescribed by the token). These operations automatically do a liveness detection (if requested) before performing the biometric operations. If the job succeeds the user is done. Otherwise the user is shortly notified about the failure and the procedure is restarted up to a maximum number of tries.

Request Information

Typically an application redirects here (via HTTP 302 status code), using a application/x-www-form-urlencoded message with parameters as follows:

Response Information

The response is sent to the BWS client application using the provided return_url by sending a application/x-www-form-urlencoded message with parameters as follows:

Sample Code

// pseudo-code to verify an already registered and enrolled user
public async Task VerifyUser(string userId)
{
    // obtain a BWS token for verification
    var bcid = GetBcid(userId);
    var token = RequestBwsToken();
    // send the user to the verify user interface
    var returnUrl = WebUtility.UrlEncode("https://example.com/bwsVerifyCallback");
    var state = WebUtility.UrlEncode(userId);  // or whatever you need in the callback, should be encrypted!
    var verifyUrl = $"https://www.bioid.com/bws/uui?access_token={token}&return_url={returnUrl}&state={state}";
    RedirectTo(verifyUrl);
}

public BwsVerifyCallback(string access_token, string state, string error)
{
    // Please refer to the sample in the BWS Result Web API for a sample-implementation of this method.
}

// pseudo-code to verify an already registered and enrolled user
public void verifyUser(String userId) {
    // obtain a BWS token for verification
    String bcid = getBcid(userId);
    String token = requestBwsToken();
    // send the user to the verify user interface
    String returnUrl = URLEncoder.encode("https://example.com/bwsVerifyCallback", "UTF-8");
    String state = URLEncoder.encode(userId, "UTF-8");  // or whatever you need in the callback, should be encrypted!
    String verifyUrl = String.format("https://www.bioid.com/bws/uui?access_token=%s&return_url=%s&state=%s", token, returnUrl, state);
    redirectTo(verifyUrl);
}

public void bwsVerifyCallback(String access_token, String state, String error) {
    // Please refer to the sample in the BWS Result Web API for a sample-implementation of this method.
}