Detect faces in an image with Amazon Rekognition using an AWS SDK - AWS SDK Code Examples

There are more AWS SDK examples available in the AWS Doc SDK Examples GitHub repo.

Detect faces in an image with Amazon Rekognition using an AWS SDK

The following code examples show how to detect faces in an image with Amazon Rekognition.

For more information, see Detecting faces in an image.

.NET
AWS SDK for .NET
Note

There's more on GitHub. Find the complete example and learn how to set up and run in the AWS Code Examples Repository.

using System; using System.Collections.Generic; using System.Threading.Tasks; using Amazon.Rekognition; using Amazon.Rekognition.Model; /// <summary> /// Uses the Amazon Rekognition Service to detect faces within an image /// stored in an Amazon Simple Storage Service (Amazon S3) bucket. This /// example uses the AWS SDK for .NET version 3.7 and .NET Core 5.0. /// </summary> public class DetectFaces { public static async Task Main() { string photo = "input.jpg"; string bucket = "bucket"; var rekognitionClient = new AmazonRekognitionClient(); var detectFacesRequest = new DetectFacesRequest() { Image = new Image() { S3Object = new S3Object() { Name = photo, Bucket = bucket, }, }, // Attributes can be "ALL" or "DEFAULT". // "DEFAULT": BoundingBox, Confidence, Landmarks, Pose, and Quality. // "ALL": See https://docs.aws.amazon.com/sdkfornet/v3/apidocs/items/Rekognition/TFaceDetail.html Attributes = new List<string>() { "ALL" }, }; try { DetectFacesResponse detectFacesResponse = await rekognitionClient.DetectFacesAsync(detectFacesRequest); bool hasAll = detectFacesRequest.Attributes.Contains("ALL"); foreach (FaceDetail face in detectFacesResponse.FaceDetails) { Console.WriteLine($"BoundingBox: top={face.BoundingBox.Left} left={face.BoundingBox.Top} width={face.BoundingBox.Width} height={face.BoundingBox.Height}"); Console.WriteLine($"Confidence: {face.Confidence}"); Console.WriteLine($"Landmarks: {face.Landmarks.Count}"); Console.WriteLine($"Pose: pitch={face.Pose.Pitch} roll={face.Pose.Roll} yaw={face.Pose.Yaw}"); Console.WriteLine($"Brightness: {face.Quality.Brightness}\tSharpness: {face.Quality.Sharpness}"); if (hasAll) { Console.WriteLine($"Estimated age is between {face.AgeRange.Low} and {face.AgeRange.High} years old."); } } } catch (Exception ex) { Console.WriteLine(ex.Message); } } }

Display bounding box information for all faces in an image.

using System; using System.Collections.Generic; using System.Drawing; using System.IO; using System.Threading.Tasks; using Amazon.Rekognition; using Amazon.Rekognition.Model; /// <summary> /// Uses the Amazon Rekognition Service to display the details of the /// bounding boxes around the faces detected in an image. This example was /// created using the AWS SDK for .NET version 3.7 and .NET Core 5.0. /// </summary> public class ImageOrientationBoundingBox { public static async Task Main() { string photo = @"D:\Development\AWS-Examples\Rekognition\target.jpg"; // "photo.jpg"; var rekognitionClient = new AmazonRekognitionClient(); var image = new Amazon.Rekognition.Model.Image(); try { using var fs = new FileStream(photo, FileMode.Open, FileAccess.Read); byte[] data = null; data = new byte[fs.Length]; fs.Read(data, 0, (int)fs.Length); image.Bytes = new MemoryStream(data); } catch (Exception) { Console.WriteLine("Failed to load file " + photo); return; } int height; int width; // Used to extract original photo width/height using (var imageBitmap = new Bitmap(photo)) { height = imageBitmap.Height; width = imageBitmap.Width; } Console.WriteLine("Image Information:"); Console.WriteLine(photo); Console.WriteLine("Image Height: " + height); Console.WriteLine("Image Width: " + width); try { var detectFacesRequest = new DetectFacesRequest() { Image = image, Attributes = new List<string>() { "ALL" }, }; DetectFacesResponse detectFacesResponse = await rekognitionClient.DetectFacesAsync(detectFacesRequest); detectFacesResponse.FaceDetails.ForEach(face => { Console.WriteLine("Face:"); ShowBoundingBoxPositions( height, width, face.BoundingBox, detectFacesResponse.OrientationCorrection); Console.WriteLine($"BoundingBox: top={face.BoundingBox.Left} left={face.BoundingBox.Top} width={face.BoundingBox.Width} height={face.BoundingBox.Height}"); Console.WriteLine($"The detected face is estimated to be between {face.AgeRange.Low} and {face.AgeRange.High} years old.\n"); }); } catch (Exception ex) { Console.WriteLine(ex.Message); } } /// <summary> /// Display the bounding box information for an image. /// </summary> /// <param name="imageHeight">The height of the image.</param> /// <param name="imageWidth">The width of the image.</param> /// <param name="box">The bounding box for a face found within the image.</param> /// <param name="rotation">The rotation of the face's bounding box.</param> public static void ShowBoundingBoxPositions(int imageHeight, int imageWidth, BoundingBox box, string rotation) { float left; float top; if (rotation == null) { Console.WriteLine("No estimated orientation. Check Exif data."); return; } // Calculate face position based on image orientation. switch (rotation) { case "ROTATE_0": left = imageWidth * box.Left; top = imageHeight * box.Top; break; case "ROTATE_90": left = imageHeight * (1 - (box.Top + box.Height)); top = imageWidth * box.Left; break; case "ROTATE_180": left = imageWidth - (imageWidth * (box.Left + box.Width)); top = imageHeight * (1 - (box.Top + box.Height)); break; case "ROTATE_270": left = imageHeight * box.Top; top = imageWidth * (1 - box.Left - box.Width); break; default: Console.WriteLine("No estimated orientation information. Check Exif data."); return; } // Display face location information. Console.WriteLine($"Left: {left}"); Console.WriteLine($"Top: {top}"); Console.WriteLine($"Face Width: {imageWidth * box.Width}"); Console.WriteLine($"Face Height: {imageHeight * box.Height}"); } }
  • For API details, see DetectFaces in AWS SDK for .NET API Reference.

Java
SDK for Java 2.x
Note

There's more on GitHub. Find the complete example and learn how to set up and run in the AWS Code Examples Repository.

public static void detectFacesinImage(RekognitionClient rekClient,String sourceImage ) { try { InputStream sourceStream = new FileInputStream(sourceImage); SdkBytes sourceBytes = SdkBytes.fromInputStream(sourceStream); // Create an Image object for the source image. Image souImage = Image.builder() .bytes(sourceBytes) .build(); DetectFacesRequest facesRequest = DetectFacesRequest.builder() .attributes(Attribute.ALL) .image(souImage) .build(); DetectFacesResponse facesResponse = rekClient.detectFaces(facesRequest); List<FaceDetail> faceDetails = facesResponse.faceDetails(); for (FaceDetail face : faceDetails) { AgeRange ageRange = face.ageRange(); System.out.println("The detected face is estimated to be between " + ageRange.low().toString() + " and " + ageRange.high().toString() + " years old."); System.out.println("There is a smile : "+face.smile().value().toString()); } } catch (RekognitionException | FileNotFoundException e) { System.out.println(e.getMessage()); System.exit(1); } }
  • For API details, see DetectFaces in AWS SDK for Java 2.x API Reference.

Kotlin
SDK for Kotlin
Note

This is prerelease documentation for a feature in preview release. It is subject to change.

Note

There's more on GitHub. Find the complete example and learn how to set up and run in the AWS Code Examples Repository.

suspend fun detectFacesinImage(sourceImage: String?) { val souImage = Image { bytes = (File(sourceImage).readBytes()) } val request = DetectFacesRequest { attributes = listOf(Attribute.All) image = souImage } RekognitionClient { region = "us-east-1" }.use { rekClient -> val response = rekClient.detectFaces(request) response.faceDetails?.forEach { face -> val ageRange = face.ageRange println("The detected face is estimated to be between ${ageRange?.low} and ${ageRange?.high} years old.") println("There is a smile ${face.smile?.value}") } } }
  • For API details, see DetectFaces in AWS SDK for Kotlin API reference.

Python
SDK for Python (Boto3)
Note

There's more on GitHub. Find the complete example and learn how to set up and run in the AWS Code Examples Repository.

class RekognitionImage: """ Encapsulates an Amazon Rekognition image. This class is a thin wrapper around parts of the Boto3 Amazon Rekognition API. """ def __init__(self, image, image_name, rekognition_client): """ Initializes the image object. :param image: Data that defines the image, either the image bytes or an Amazon S3 bucket and object key. :param image_name: The name of the image. :param rekognition_client: A Boto3 Rekognition client. """ self.image = image self.image_name = image_name self.rekognition_client = rekognition_client def detect_faces(self): """ Detects faces in the image. :return: The list of faces found in the image. """ try: response = self.rekognition_client.detect_faces( Image=self.image, Attributes=['ALL']) faces = [RekognitionFace(face) for face in response['FaceDetails']] logger.info("Detected %s faces.", len(faces)) except ClientError: logger.exception("Couldn't detect faces in %s.", self.image_name) raise else: return faces
  • For API details, see DetectFaces in AWS SDK for Python (Boto3) API Reference.