OSS face detection - detect and analyze facial attributes - Object Storage Service

Overview

Face detection uses image AI to identify faces in an image and return attributes for each detected face.

Note

Face information includes face ID, age, gender, mood, attractiveness, face quality, and face attributes (position, head orientation, glasses, beard, and mask).

Use cases

Face recognition: Detect and compare faces against a database for authentication and access control.
Face authentication: Verify user identity for scenarios such as phone unlocking and payment verification.
Facial expression analysis: Analyze facial expressions for sentiment analysis, human-computer interaction, and virtual characters.
Note
- Background clutter: Complex backgrounds may interfere with facial feature detection.
- Face occlusion: Overlapping faces in an image may reduce detection accuracy.

How to use

Prerequisites

Activate Intelligent Media Management (IMM).
Create a bucket in OSS and upload the files that you want to process to the bucket.
Create and bind an IMM project. You can bind the project in the OSS console or by calling an API operation. The IMM project must be in the same region as the bucket.
Grant the required permissions to the user.

Face detection

The following examples show how to detect faces using OSS SDKs. For other languages, adapt the parameters accordingly.

Java

OSS SDK for Java 3.17.4 or later is required.

import com.aliyun.oss.ClientBuilderConfiguration;
import com.aliyun.oss.OSS;
import com.aliyun.oss.OSSClientBuilder;
import com.aliyun.oss.common.auth.CredentialsProviderFactory;
import com.aliyun.oss.common.auth.EnvironmentVariableCredentialsProvider;
import com.aliyun.oss.common.comm.SignVersion;
import com.aliyun.oss.model.OSSObject;
import com.aliyun.oss.model.GetObjectRequest;
import com.aliyuncs.exceptions.ClientException;

import java.io.ByteArrayOutputStream;
import java.io.IOException;

public class Demo1 {
    public static void main(String[] args) throws ClientException, ClientException {
        // Specify the endpoint of the region in which the bucket is located.
        String endpoint = "https://oss-cn-hangzhou.aliyuncs.com";
        // Specify the ID of the Alibaba Cloud region in which the bucket is located. Example: cn-hangzhou.
        String region = "cn-hangzhou";
        // Obtain access credentials from environment variables. Before you run the sample code, make sure that the OSS_ACCESS_KEY_ID and OSS_ACCESS_KEY_SECRET environment variables are configured.
        EnvironmentVariableCredentialsProvider credentialsProvider = CredentialsProviderFactory.newEnvironmentVariableCredentialsProvider();
        // Specify the name of the bucket.
        String bucketName = "examplebucket";
        // If the image is stored in the root directory of the bucket, enter the image name. If the image is not stored in the root directory of the bucket, you must specify the full path of the image. Example: exampledir/example.jpg.
        String key = "example.jpg";

        // Create an OSSClient instance.
        // Call the shutdown method to release resources when the OSSClient is no longer in use.
        ClientBuilderConfiguration clientBuilderConfiguration = new ClientBuilderConfiguration();
        clientBuilderConfiguration.setSignatureVersion(SignVersion.V4);
        OSS ossClient = OSSClientBuilder.create()
                .endpoint(endpoint)
                .credentialsProvider(credentialsProvider)
                .clientConfiguration(clientBuilderConfiguration)
                .region(region)
                .build();

        try {
            // Create a processing instruction to use face detection.
            GetObjectRequest getObjectRequest = new GetObjectRequest(bucketName, key);
            getObjectRequest.setProcess("image/faces");

            // Use the getObject method and pass the processing instruction by using the process parameter.
            OSSObject ossObject = ossClient.getObject(getObjectRequest);

            // Read and display the query results.
            ByteArrayOutputStream baos = new ByteArrayOutputStream();
            byte[] buffer = new byte[1024];
            int bytesRead;
            while ((bytesRead = ossObject.getObjectContent().read(buffer)) != -1) {
                baos.write(buffer, 0, bytesRead);
            }
            String imageFaces = baos.toString("UTF-8");
            System.out.println("Image Faces:");
            System.out.println(imageFaces);
        } catch (IOException e) {
            System.out.println("Error: " + e.getMessage());
        } finally {
            // Shut down the OSSClient instance.
            ossClient.shutdown();
        }
    }
}

Python

OSS SDK for Python 2.18.4 or later is required.

# -*- coding: utf-8 -*-
import oss2
from oss2.credentials import EnvironmentVariableCredentialsProvider

# Obtain access credentials from environment variables. Before you run the sample code, make sure that the OSS_ACCESS_KEY_ID and OSS_ACCESS_KEY_SECRET environment variables are configured.
auth = oss2.ProviderAuthV4(EnvironmentVariableCredentialsProvider())

# Specify the endpoint of the region where the bucket is located.
endpoint = 'https://oss-cn-hangzhou.aliyuncs.com'
# Specify the ID of the Alibaba Cloud region in which the bucket is located.
region = 'cn-hangzhou'
bucket = oss2.Bucket(auth, endpoint, 'examplebucket', region=region)

# If the image is stored in the root directory, enter the image name. Otherwise, specify the full path.
key = 'example.jpg'

# Create a processing instruction to use face detection.
process = 'image/faces'

try:
    # Use the get_object method and pass the processing instruction by using the process parameter.
    result = bucket.get_object(key, process=process)

    # Read and display the query results.
    image_faces = result.read().decode('utf-8')
    print("Image Faces:")
    print(image_faces)
except oss2.exceptions.OssError as e:
    print("Error:", e)

Go

OSS SDK for Go 3.0.2 or later is required.

package main

import (
	"fmt"
	"io"
	"os"

	"github.com/aliyun/aliyun-oss-go-sdk/oss"
)

func main() {
	// Obtain the temporary access credentials from the environment variables. Before you run the sample code, make sure that the OSS_ACCESS_KEY_ID and OSS_ACCESS_KEY_SECRET environment variables are configured.
	provider, err := oss.NewEnvironmentVariableCredentialsProvider()
	if err != nil {
		fmt.Println("Error:", err)
		os.Exit(-1)
	}
	// Create an OSSClient instance.
	// Specify the endpoint of the region in which the bucket is located. For example, if the bucket is located in the China (Hangzhou) region, set the endpoint to https://oss-cn-hangzhou.aliyuncs.com. Specify your actual endpoint.
	// Specify the ID of the Alibaba Cloud region in which the bucket is located. Example: cn-hangzhou.
	client, err := oss.New("https://oss-cn-hangzhou.aliyuncs.com", "", "", oss.SetCredentialsProvider(&provider), oss.AuthVersion(oss.AuthV4), oss.Region("cn-hangzhou"))
	if err != nil {
		fmt.Println("Error:", err)
		os.Exit(-1)
	}
	// Specify the name of the bucket. Example: examplebucket.
	bucketName := "examplebucket"

	bucket, err := client.Bucket(bucketName)
	if err != nil {
		fmt.Println("Error:", err)
		os.Exit(-1)
	}
	// If the image is stored in the root directory of the bucket, enter the image name. If the image is not stored in the root directory of the bucket, you must specify the full path of the image. Example: exampledir/example.jpg.
	// Use the oss.Process method to create a processing instruction to use face detection.
	body, err := bucket.GetObject("example.jpg", oss.Process("image/faces"))
	if err != nil {
		fmt.Println("Error:", err)
		os.Exit(-1)
	}

	defer body.Close()

	data, err := io.ReadAll(body)
	if err != nil {
		fmt.Println("Error:", err)
		os.Exit(-1)
	}
	fmt.Println("data:", string(data))
}

PHP

OSS SDK for PHP 2.7.0 or later is required.

<?php
if (is_file(__DIR__ . '/../autoload.php')) {
    require_once __DIR__ . '/../autoload.php';
}
if (is_file(__DIR__ . '/../vendor/autoload.php')) {
    require_once __DIR__ . '/../vendor/autoload.php';
}
use OSS\Credentials\EnvironmentVariableCredentialsProvider;
use OSS\OssClient;

try {
    // Obtain access credentials from environment variables. Before you run the sample code, make sure that the OSS_ACCESS_KEY_ID and OSS_ACCESS_KEY_SECRET environment variables are configured.
    $provider = new EnvironmentVariableCredentialsProvider(); 
    // Specify the endpoint of the region in which the bucket is located. For example, if the bucket is located in the China (Hangzhou) region, set the endpoint to https://oss-cn-hangzhou.aliyuncs.com.
    $endpoint = 'https://oss-cn-hangzhou.aliyuncs.com';
    // Specify the name of the bucket. Example: examplebucket.
    $bucket = 'examplebucket';
    // If the image is stored in the root directory of the bucket, enter the image name. If the image is not stored in the root directory of the bucket, you must specify the full path of the image. Example: exampledir/example.jpg.
    $key = 'example.jpg'; 

    $config = array(
        "provider" => $provider,
        "endpoint" => $endpoint,        
        "signatureVersion" => OssClient::OSS_SIGNATURE_VERSION_V4,
        // Specify the ID of the Alibaba Cloud region in which the bucket is located.
        "region" => "cn-hangzhou"
    );
    $ossClient = new OssClient($config);
  // Create a processing instruction to use face detection.
  $options[$ossClient::OSS_PROCESS] = "image/faces";
  $result = $ossClient->getObject($bucket,$key,$options);
  var_dump($result);
} catch (OssException $e) {
  printf($e->getMessage() . "\n");
  return;
}

Parameters

Action: image/faces

Note

For response field details, see the DetectImageFaces API reference.

Related API operations

To call the RESTful API directly, include signature calculation in your code. Use the (Recommended) Include a V4 signature method for the Authorization header.

Process images by adding the x-oss-process parameter to the GetObject operation. GetObject.

Sample request

GET /example.jpg?x-oss-process=image/faces HTTP/1.1
Host: image-demo.oss-cn-hangzhou.aliyuncs.com
Date: Fri, 21 Jul 2023 08:57:30 GMT
Authorization: SignatureValue

Sample success response

HTTP/1.1 200 OK
Server: AliyunOSS
Date: Fri, 21 Jul 2023 08:57:30 GMT
Content-Type: application/json;charset=utf-8
Content-Length: 161
Connection: keep-alive
x-oss-request-id: 628E2481184E20F26C000009
x-oss-transfer-acc-type: acc-none
x-oss-data-location: oss-cn-hangzhou-a
ETag: "D0F162350DA037F4DC2A142B2E116BD0"
Last-Modified: Wed, 25 May 2022 12:20:34 GMT
x-oss-object-type: Normal
x-oss-hash-crc64ecma: 2040549661341440100
x-oss-storage-class: Standard
x-oss-server-time: 12437

{
    "RequestId": "5F2389FE-A5E3-076F-B071-43A33DB0D716",
    "Figures": [{
        "Beard": "none",
        "MaskConfidence": 0.7509999871253967,
        "Gender": "male",
        "Boundary": {
            "Left": 280,
            "Top": 36,
            "Height": 87,
            "Width": 70
        },
        "BeardConfidence": 0.9980000257492065,
        "FigureId": "d39651db-9dc4-469f-8834-d2fcf30e179e",
        "Mouth": "open",
        "Emotion": "none",
        "Age": 12,
        "MouthConfidence": 0.5669999718666077,
        "FigureType": "face",
        "GenderConfidence": 0.9509999752044678,
        "HeadPose": {
            "Pitch": -12.309000015258789,
            "Roll": -11.362000465393066,
            "Yaw": 3.443000078201294
        },
        "Mask": "none",
        "EmotionConfidence": 0.9950000047683716,
        "HatConfidence": 0.9879999756813049,
        "GlassesConfidence": 1,
        "Sharpness": 0.8870000243186951,
        "FigureClusterId": "figure-cluster-id-unavailable",
        "FaceQuality": 0.8289999961853027,
        "Attractive": 0.12099999934434891,
        "AgeSD": 5,
        "Glasses": "none",
        "FigureConfidence": 0.9990000128746033,
        "Hat": "hat"
    }
    ]
}

Billing

Face detection incurs charges from both OSS and IMM:

OSS: OSS Pricing

API	Billable item	Description
GetObject	GET requests	You are charged request fees based on the number of successful requests.
	outbound traffic over Internet	If you call the GetObject operation by using a public endpoint, such as oss-cn-hangzhou.aliyuncs.com, or an acceleration endpoint, such as oss-accelerate.aliyuncs.com, you are charged fees for outbound traffic over the Internet based on the data size.
	Retrieval of IA objects	If IA objects are retrieved, you are charged IA data retrieval fees based on the size of retrieved IA data.
	Transfer acceleration	If you enable transfer acceleration and use an acceleration endpoint to access your bucket, you are charged transfer acceleration fees based on the data size.
HeadObject	GET requests	You are charged request fees based on the number of successful requests.

IMM: IMM billable items

Important

Starting from 11:00 on July 28, 2025 (UTC+8), the price of IMM face detection service remains unchanged, but the billable item name is changed from ImageFace to ImageDetect. For more information, see IMM billing adjustment notice.

API	Billable item	Description
DetectImageFaces	ImageDetect	You are charged request fees based on the number of successful requests.

Limits

Only synchronous processing (x-oss-process) is supported.
Anonymous access will be denied.