Face API - V1.0

This API is currently available in:

  • West US - westus.api.cognitive.microsoft.com
  • West US 2 - westus2.api.cognitive.microsoft.com
  • East US - eastus.api.cognitive.microsoft.com
  • East US 2 - eastus2.api.cognitive.microsoft.com
  • West Central US - westcentralus.api.cognitive.microsoft.com
  • South Central US - southcentralus.api.cognitive.microsoft.com
  • West Europe - westeurope.api.cognitive.microsoft.com
  • North Europe - northeurope.api.cognitive.microsoft.com
  • Southeast Asia - southeastasia.api.cognitive.microsoft.com
  • East Asia - eastasia.api.cognitive.microsoft.com
  • Australia East - australiaeast.api.cognitive.microsoft.com
  • Brazil South - brazilsouth.api.cognitive.microsoft.com
  • Canada Central - canadacentral.api.cognitive.microsoft.com
  • Central India - centralindia.api.cognitive.microsoft.com
  • UK South - uksouth.api.cognitive.microsoft.com
  • Japan East - japaneast.api.cognitive.microsoft.com

Face - Identify

1-to-many identification to find the closest matches of the specific query person face from a person group or large person group.

For each face in the faceIds array, Face Identify will compute similarities between the query face and all the faces in the person group (given by personGroupId) or large person group (given by largePersonGroupId), and return candidate person(s) for that face ranked by similarity confidence. The person group/large person group should be trained to make it ready for identification. See more in PersonGroup - Train and LargePersonGroup - Train.

Remarks:

  • The algorithm allows more than one face to be identified independently at the same request, but no more than 10 faces.
  • Each person in the person group/large person group could have more than one face, but no more than 248 faces.
  • Higher face image quality means better identification precision. Please consider high-quality faces: frontal, clear, and face size is 200x200 pixels (100 pixels between eyes) or bigger.
  • Number of candidates returned is restricted by maxNumOfCandidatesReturned and confidenceThreshold. If no person is identified, the returned candidates will be an empty array.
  • Try Face - Find Similar when you need to find similar faces from a face list/large face list instead of a person group/large person group.

Http Method

POST

West US West US 2 East US East US 2 West Central US South Central US West Europe North Europe Southeast Asia East Asia Australia East Brazil South Canada Central Central India UK South Japan East

Request URL

Request headers

(optional)
string
Media type of the body sent to the API.
string
Subscription key which provides access to this API. Found in your Cognitive Services accounts.

Request body

JSON fields in request body:

Fields Type Description
faceIds Array Array of query faces faceIds, created by the Face - Detect. Each of the faces are identified independently. The valid number of faceIds is between [1, 10].
personGroupId String personGroupId of the target person group, created by PersonGroup - Create. Parameter personGroupId and largePersonGroupId should not be provided at the same time.
largePersonGroupId String largePersonGroupId of the target large person group, created by LargePersonGroup - Create. Parameter personGroupId and largePersonGroupId should not be provided at the same time.
maxNumOfCandidatesReturned (optional) Number The range of maxNumOfCandidatesReturned is between 1 and 100 (default is 10).
confidenceThreshold (optional) Number Optional parameter.
Customized identification confidence threshold, in the range of [0, 1]. Advanced user can tweak this value to override default internal threshold for better precision on their scenario data. Note there is no guarantee of this threshold value working on other data and after algorithm updates.

{
    "largePersonGroupId": "sample_group",
    "faceIds": [
        "c5c24a82-6845-4031-9d5d-978df9175426",
        "65d083d4-9447-47d1-af30-b626144bf0fb"
    ],
    "maxNumOfCandidatesReturned": 1,
    "confidenceThreshold": 0.5
}

Response 200

A successful call returns the identified candidate person(s) for each query face.

JSON fields in response body:

FieldsTypeDescription
faceIdStringfaceId of the query face.
candidatesArrayIdentified person candidates for that face (ranked by confidence). Array size should be no larger than input maxNumOfCandidatesReturned. If no person is identified, will return an empty array.
personIdStringpersonId of candidate person.
confidenceNumberA float number between 0.0 and 1.0.

{
    [
        {
            "faceId": "c5c24a82-6845-4031-9d5d-978df9175426",
            "candidates": [
                {
                    "personId": "25985303-c537-4467-b41d-bdb45cd95ca1",
                    "confidence": 0.92
                }
            ]
        },
        {
            "faceId": "65d083d4-9447-47d1-af30-b626144bf0fb",
            "candidates": [
                {
                    "personId": "2ae4935b-9659-44c3-977f-61fac20d0538",
                    "confidence": 0.89
                }
            ]
        }
    ]
}

Response 400

Error code and message returned in JSON:

Error CodeError Message Description
BadArgumentInvalid request body.
BadArgumentThe argument maxNumOfCandidatesReturned is not valid. Range is [1,5]
BadArgumentThe argument confidenceThreshold is not valid. Range is [0, 1]
BadArgumentFace ID is invalid.
BadArgumentPerson group ID is invalid. Valid format should be a string composed by numbers, English letters in lower case, '-', '_', and no longer than 64 characters.
BadArgumentLarge person group ID is invalid. Valid format should be a string composed by numbers, English letters in lower case, '-', '_', and no longer than 64 characters.
PersonGroupIdAndLargePersonGroupIdBothNotNullLarge person group ID and person group ID are both not null.
PersonGroupIdAndLargePersonGroupIdBothNullLarge person group ID and person group ID are both null.
PersonGroupNotFoundPerson group is not found.
LargePersonGroupNotFoundLarge person group is not found.
FaceNotFoundFace is not found.
PersonGroupNotTrainedPerson group not trained.
LargePersonGroupNotTrainedLarge person group not trained.
PersonGroupTrainingNotFinishedPerson group is under training.
LargePersonGroupTrainingNotFinishedLarge person group is under training.

{
    "error": {
        "code": "BadArgument",
        "message": "Large Person group is invalid."
    }
}

Response 401

Error code and message returned in JSON:

Error CodeError Message Description
BadArgumentInvalid request body.
BadArgumentThe argument maxNumOfCandidatesReturned is not valid.
BadArgumentThe argument confidenceThreshold is not valid.
BadArgumentFace ID is invalid.
BadArgumentThe length of faceIds is not in a valid range.
BadArgumentPerson group ID is invalid. Valid format should be a string composed by numbers, English letters in lower case, '-', '_', and no longer than 64 characters.
BadArgumentLarge person group ID is invalid. Valid format should be a string composed by numbers, English letters in lower case, '-', '_', and no longer than 64 characters.
PersonGroupIdAndLargePersonGroupIdBothNotNullLarge person group ID and person group ID are both not null.
PersonGroupIdAndLargePersonGroupIdBothNullLarge person group ID and person group ID are both null.
PersonGroupNotFoundPerson group is not found.
LargePersonGroupNotFoundLarge person group is not found.
FaceNotFoundFace is not found.
PersonGroupNotTrainedPerson group not trained.
LargePersonGroupNotTrainedLarge person group not trained.

{
    "error": {
        "code": "Unspecified",
        "message": "Access denied due to invalid subscription key. Make sure you are subscribed to an API you are trying to call and provide the right key."
    }
}

Response 403

{
    "error": {
        "statusCode": 403,
        "message": "Out of call volume quota. Quota will be replenished in 2 days."
    }
}

Response 409

Training process is conflict with identify. Try identify again when training is finished.

{
    "error": {
        "code": "LargePersonGroupTrainingNotFinished",
        "message": "Large person group is under training."
    }
}

Response 415

Unsupported media type error. Only "application/json" is valid for this API.

{
    "error": {
        "code": "BadArgument",
        "message": "Invalid Media Type."
    }
}

Response 429

{
    "error": {
        "statusCode": 429,
        "message": "Rate limit is exceeded. Try again in 26 seconds."
    }
}

Code samples

@ECHO OFF

curl -v -X POST "https://westus.api.cognitive.microsoft.com/face/v1.0/identify"
-H "Content-Type: application/json"
-H "Ocp-Apim-Subscription-Key: {subscription key}"

--data-ascii "{body}" 
using System;
using System.Net.Http.Headers;
using System.Text;
using System.Net.Http;
using System.Web;

namespace CSHttpClientSample
{
    static class Program
    {
        static void Main()
        {
            MakeRequest();
            Console.WriteLine("Hit ENTER to exit...");
            Console.ReadLine();
        }
        
        static async void MakeRequest()
        {
            var client = new HttpClient();
            var queryString = HttpUtility.ParseQueryString(string.Empty);

            // Request headers
            client.DefaultRequestHeaders.Add("Ocp-Apim-Subscription-Key", "{subscription key}");

            var uri = "https://westus.api.cognitive.microsoft.com/face/v1.0/identify?" + queryString;

            HttpResponseMessage response;

            // Request body
            byte[] byteData = Encoding.UTF8.GetBytes("{body}");

            using (var content = new ByteArrayContent(byteData))
            {
               content.Headers.ContentType = new MediaTypeHeaderValue("< your content type, i.e. application/json >");
               response = await client.PostAsync(uri, content);
            }

        }
    }
}	
// // This sample uses the Apache HTTP client from HTTP Components (http://hc.apache.org/httpcomponents-client-ga/)
import java.net.URI;
import org.apache.http.HttpEntity;
import org.apache.http.HttpResponse;
import org.apache.http.client.HttpClient;
import org.apache.http.client.methods.HttpGet;
import org.apache.http.client.utils.URIBuilder;
import org.apache.http.impl.client.HttpClients;
import org.apache.http.util.EntityUtils;

public class JavaSample 
{
    public static void main(String[] args) 
    {
        HttpClient httpclient = HttpClients.createDefault();

        try
        {
            URIBuilder builder = new URIBuilder("https://westus.api.cognitive.microsoft.com/face/v1.0/identify");


            URI uri = builder.build();
            HttpPost request = new HttpPost(uri);
            request.setHeader("Content-Type", "application/json");
            request.setHeader("Ocp-Apim-Subscription-Key", "{subscription key}");


            // Request body
            StringEntity reqEntity = new StringEntity("{body}");
            request.setEntity(reqEntity);

            HttpResponse response = httpclient.execute(request);
            HttpEntity entity = response.getEntity();

            if (entity != null) 
            {
                System.out.println(EntityUtils.toString(entity));
            }
        }
        catch (Exception e)
        {
            System.out.println(e.getMessage());
        }
    }
}

<!DOCTYPE html>
<html>
<head>
    <title>JSSample</title>
    <script src="http://ajax.googleapis.com/ajax/libs/jquery/1.9.0/jquery.min.js"></script>
</head>
<body>

<script type="text/javascript">
    $(function() {
        var params = {
            // Request parameters
        };
      
        $.ajax({
            url: "https://westus.api.cognitive.microsoft.com/face/v1.0/identify?" + $.param(params),
            beforeSend: function(xhrObj){
                // Request headers
                xhrObj.setRequestHeader("Content-Type","application/json");
                xhrObj.setRequestHeader("Ocp-Apim-Subscription-Key","{subscription key}");
            },
            type: "POST",
            // Request body
            data: "{body}",
        })
        .done(function(data) {
            alert("success");
        })
        .fail(function() {
            alert("error");
        });
    });
</script>
</body>
</html>
#import <Foundation/Foundation.h>

int main(int argc, const char * argv[])
{
    NSAutoreleasePool * pool = [[NSAutoreleasePool alloc] init];
    
    NSString* path = @"https://westus.api.cognitive.microsoft.com/face/v1.0/identify";
    NSArray* array = @[
                         // Request parameters
                         @"entities=true",
                      ];
    
    NSString* string = [array componentsJoinedByString:@"&"];
    path = [path stringByAppendingFormat:@"?%@", string];

    NSLog(@"%@", path);

    NSMutableURLRequest* _request = [NSMutableURLRequest requestWithURL:[NSURL URLWithString:path]];
    [_request setHTTPMethod:@"POST"];
    // Request headers
    [_request setValue:@"application/json" forHTTPHeaderField:@"Content-Type"];
    [_request setValue:@"{subscription key}" forHTTPHeaderField:@"Ocp-Apim-Subscription-Key"];
    // Request body
    [_request setHTTPBody:[@"{body}" dataUsingEncoding:NSUTF8StringEncoding]];
    
    NSURLResponse *response = nil;
    NSError *error = nil;
    NSData* _connectionData = [NSURLConnection sendSynchronousRequest:_request returningResponse:&response error:&error];

    if (nil != error)
    {
        NSLog(@"Error: %@", error);
    }
    else
    {
        NSError* error = nil;
        NSMutableDictionary* json = nil;
        NSString* dataString = [[NSString alloc] initWithData:_connectionData encoding:NSUTF8StringEncoding];
        NSLog(@"%@", dataString);
        
        if (nil != _connectionData)
        {
            json = [NSJSONSerialization JSONObjectWithData:_connectionData options:NSJSONReadingMutableContainers error:&error];
        }
        
        if (error || !json)
        {
            NSLog(@"Could not parse loaded json with error:%@", error);
        }
        
        NSLog(@"%@", json);
        _connectionData = nil;
    }
    
    [pool drain];

    return 0;
}
<?php
// This sample uses the Apache HTTP client from HTTP Components (http://hc.apache.org/httpcomponents-client-ga/)
require_once 'HTTP/Request2.php';

$request = new Http_Request2('https://westus.api.cognitive.microsoft.com/face/v1.0/identify');
$url = $request->getUrl();

$headers = array(
    // Request headers
    'Content-Type' => 'application/json',
    'Ocp-Apim-Subscription-Key' => '{subscription key}',
);

$request->setHeader($headers);

$parameters = array(
    // Request parameters
);

$url->setQueryVariables($parameters);

$request->setMethod(HTTP_Request2::METHOD_POST);

// Request body
$request->setBody("{body}");

try
{
    $response = $request->send();
    echo $response->getBody();
}
catch (HttpException $ex)
{
    echo $ex;
}

?>
########### Python 2.7 #############
import httplib, urllib, base64

headers = {
    # Request headers
    'Content-Type': 'application/json',
    'Ocp-Apim-Subscription-Key': '{subscription key}',
}

params = urllib.urlencode({
})

try:
    conn = httplib.HTTPSConnection('westus.api.cognitive.microsoft.com')
    conn.request("POST", "/face/v1.0/identify?%s" % params, "{body}", headers)
    response = conn.getresponse()
    data = response.read()
    print(data)
    conn.close()
except Exception as e:
    print("[Errno {0}] {1}".format(e.errno, e.strerror))

####################################

########### Python 3.2 #############
import http.client, urllib.request, urllib.parse, urllib.error, base64

headers = {
    # Request headers
    'Content-Type': 'application/json',
    'Ocp-Apim-Subscription-Key': '{subscription key}',
}

params = urllib.parse.urlencode({
})

try:
    conn = http.client.HTTPSConnection('westus.api.cognitive.microsoft.com')
    conn.request("POST", "/face/v1.0/identify?%s" % params, "{body}", headers)
    response = conn.getresponse()
    data = response.read()
    print(data)
    conn.close()
except Exception as e:
    print("[Errno {0}] {1}".format(e.errno, e.strerror))

####################################
require 'net/http'

uri = URI('https://westus.api.cognitive.microsoft.com/face/v1.0/identify')
uri.query = URI.encode_www_form({
})

request = Net::HTTP::Post.new(uri.request_uri)
# Request headers
request['Content-Type'] = 'application/json'
# Request headers
request['Ocp-Apim-Subscription-Key'] = '{subscription key}'
# Request body
request.body = "{body}"

response = Net::HTTP.start(uri.host, uri.port, :use_ssl => uri.scheme == 'https') do |http|
    http.request(request)
end

puts response.body