Web Identify API

GET /identify


Performs a one-to-many comparison of the uploaded samples with stored biometric templates in order to identify the individuals that are most likely represented by the given samples.

The samples to be identified are those that have previously uploaded (see Upload Web API) using the same token that has been used for the authorization of this call. These samples are fetched from the BWS storage (and removed from the storage, so that they cannot be used for any other purpose), sent to the live data detection procedure and finally, if the liveness detection determined that the given data is live data (or liveness detection is disabled) transferred to the identification procedure.

The biometric templates which are compared against the samples are taken from the storage and partition as specified by the BCID in the provided BWS token.

Response Information

Authentication

This API call requires BWS Token Authentication, i.e. you have to provide an HTTP authorization header using the authorization method Bearer (for compatibility issues you can also use the JWT identifier) and a previously issued BWS token, which can be requested using the Token Web API.

Parameters

livedetection

Optional, defaults to the setting in the BWS Token. A boolean parameter to explicitly switch on live data detection.

When set to true or if the provided BWS token requires liveness detection the operation typically fails as soon as it cannot undoubtedly determine that the given data is live data. Note that for liveness detection to work at least two face- or periocular-samples need to be uploaded.

No live data detection will be performed if the token does not require liveness detection and this flag is set to false.

maxResults Optional, defaults to 20. The maximum number of matches that shall be returned in the matches array, a sorted array of biometric class IDs together with their score representing the individuals that have been identified.

Response Information

The Identify Web API returns a IdentifyResult object that contains the flag Success, which shows, whether the identification could be performed or not. In case that the identification failed (i.e. Success is set to false) an Error is reported:

null (i.e no error) Typically there are simply no users enrolled in the specified partition.
LiveDetectionFailed The submitted samples do not prove that they are recorded from a live person.
ChallengeResponseFailed The submitted samples do not prove that they are recorded from a live person as they do not fulfill the challenge-response criteria.
NotEnoughSamples Not enough valid samples have been provided.
ExecutionOfJobTimedOut Server seems to be too busy.


Response Body Format

application/json, text/json
Successful IdentifyResult Sample:
{
  "Success": true,
  "Matches":[
    {"Score":0.73721338244277179,"Storage":"bioid","Partition":9876,"ClassID":12345},
    {"Score":0.4841065082191604,"Storage":"bioid","Partition":9876,"ClassID":54321},
    ... ]
}

Failed IdentifyResult Sample:
{ 
  "Success": false, 
  "Error": "LiveDetectionFailed"
}

Response HTTP Status Codes

The call returns one of the standard HTTP status codes. With the success code (200) you receive the IdentifyResult object in the body text. With erroneous codes you typically get a Message field within the body text describing the error. The most commonly returned codes are:

200 OK The response body contains the IdentifyResult object.
400 Bad Request No samples have been uploaded.
401 Unauthorized No or an invalid authentication header has been specified. This call requires JWT Bearer Token Authentication. If a BWS token has been passed, this error typically indicates that the token has expired.
403 Forbidden The number of allowed identification attempts with this token has been exceeded.
500 Internal Server Error A server side exception occurred.

Sample Code

[DataContract]
public class Match
{
    [DataMember] public double Score { get; set; }
    [DataMember] public string Storage { get; set; }
    [DataMember] public int Partition { get; set; }
    [DataMember] public int ClassID { get; set; }
}
 
[DataContract]
public class IdentificationResult
{
    [DataMember] public bool Success { get; set; }
    [DataMember] public string Error { get; set; }
    [DataMember] public List<Match> Matches { get; set; }
}

// ...

using (var client = new HttpClient())
{
    client.DefaultRequestHeaders.Authorization = new AuthenticationHeaderValue("Bearer", token);
    using (var response = await client.GetAsync(ENDPOINT + $"identify"))
    {
        if (response.StatusCode == HttpStatusCode.OK)
        {
            var dcs = new DataContractJsonSerializer(typeof(IdentificationResult));
            using (var stream = await response.Content.ReadAsStreamAsync())
            {
                var json = (IdentificationResult)dcs.ReadObject(stream);
                return json.Success;
            }
        }
    }
}

For a complete sample refer to the walk-through .

jQuery.ajax({
    url: "https://bws.bioid.com/extension/identify",
    type: "GET",
    headers: {
        "Authorization": "Bearer " + token,
    },
}).done(function(data, textStatus, jqXHR) {
    if (data.Success) {
	    console.log("identification succeeded");
  	} else {
    	console.log("identification failed", data.Error);
  	}
});

See also: method performTask in bws.capture.js, which is part of the BWS unified user interface.

// using OkHttpClient from the OkHttp library
Request request = new Request.Builder()
        .url("https://bws.bioid.com/extension/identify")
        .addHeader("Authorization", "Bearer " + token)
        .build();
OkHttpClient client = new OkHttpClient();
Response response = client.newCall(request).execute();
if (response.code() == 200) {
    // using org.json.JSONObject from JSON-java library
    JSONObject json = new JSONObject(response.body().string());
    if (json.getBoolean("Success")) {
        System.out.println("identify succeeded");
    } else {
        System.out.println("identify failed: " + json.getString("Error"));
    }
}