Dart
Dart
Amazon Rekognition - Detect Faces in an Image
See more Amazon Rekognition Examples
Detects faces within an image that is provided as input. This example passes theimage as base64-encoded image bytes.Chilkat Dart Downloads
import 'package:chilkat/chilkat.dart';
void main() {
final rest = CkRest();
final authAws = CkAuthAws();
authAws.accessKey = 'AWS_ACCESS_KEY';
authAws.secretKey = 'AWS_SECRET_KEY';
// Don't forget to change the region to your particular region. (Also make the same change in the call to Connect below.)
authAws.region = 'us-west-2';
authAws.serviceName = 'rekognition';
// SetAuthAws causes Chilkat to automatically add the following headers: Authorization, X-Amz-Date
rest.setAuthAws(authAws);
// URL: https://rekognition.us-west-2.amazonaws.com/
final bTls = true;
final port = 443;
final bAutoReconnect = true;
// Don't forget to change the region domain (us-west-2.amazonaws.com) to your particular region.
try {
rest.connect('rekognition.us-west-2.amazonaws.com', port, bTls, bAutoReconnect);
} on ChilkatException catch (e) {
print('ConnectFailReason: ${rest.connectFailReason}');
print(e.lastErrorText);
return;
}
// Note: The above code does not need to be repeatedly called for each REST request.
// The rest object can be setup once, and then many requests can be sent. Chilkat will automatically
// reconnect within a FullRequest* method as needed. It is only the very first connection that is explicitly
// made via the Connect method.
// Load the JPG to be passed as base64 in the JSON.
final bdJpg = CkBinData();
try {
bdJpg.loadFile('qa_data/jpg/kid_blue_coat.jpg');
} on ChilkatException {
print('Failed to load the input JPG file.');
return;
}
// We wish to send the following JSON in the body of our HTTP request:
// {
// "Image": {
// "Bytes": "base64_image_bytes"
// }
// "Attributes": [
// "ALL"
// ]
// }
// Here is the image we used for testing:
// (image:https://example-code.com/images/kid_blue_coat.jpg/endImage)
// Convert binary image bytes to base64.
// Note: We are explicitly keeping the data inside Chilkat to avoid having to pass large strings
// as arguments to function calls. This is important for some programming languages.
final sbJpg = CkStringBuilder();
bdJpg.getEncodedSb('base64', sbJpg);
final json = CkJsonObject();
json.updateSb('Image.Bytes', sbJpg);
json.updateString('Attributes[0]', 'ALL');
rest.addHeader('Content-Type', 'application/x-amz-json-1.1');
rest.addHeader('X-Amz-Target', 'RekognitionService.DetectFaces');
final sbRequestBody = CkStringBuilder();
json.emitSb(sbRequestBody);
final sbResponseBody = CkStringBuilder();
try {
rest.fullRequestSb('POST', '/', sbRequestBody, sbResponseBody);
} on ChilkatException catch (e) {
print(e.lastErrorText);
return;
}
final respStatusCode = rest.responseStatusCode;
print('response status code = $respStatusCode');
if (respStatusCode >= 400) {
print('Response Status Code = $respStatusCode');
print('Response Header:');
print(rest.responseHeader);
print('Response Body:');
print(sbResponseBody.getAsString());
return;
}
final jResp = CkJsonObject();
jResp.loadSb(sbResponseBody);
jResp.emitCompact = false;
print(jResp.emit());
// Sample JSON response:
// (Sample code for parsing the JSON response is shown below)
// {
// "FaceDetails": [
// {
// "AgeRange": {
// "High": 18,
// "Low": 8
// },
// "Beard": {
// "Confidence": 98.06282806396484,
// "Value": false
// },
// "BoundingBox": {
// "Height": 0.327279269695282,
// "Left": 0.5339247584342957,
// "Top": 0.23660442233085632,
// "Width": 0.35611653327941895
// },
// "Confidence": 99.99732971191406,
// "Emotions": [
// {
// "Confidence": 99.5849380493164,
// "Type": "HAPPY"
// },
// {
// "Confidence": 0.15533843636512756,
// "Type": "CALM"
// },
// {
// "Confidence": 0.08864031732082367,
// "Type": "SURPRISED"
// },
// {
// "Confidence": 0.05476664379239082,
// "Type": "SAD"
// },
// {
// "Confidence": 0.042048510164022446,
// "Type": "CONFUSED"
// },
// {
// "Confidence": 0.038942769169807434,
// "Type": "DISGUSTED"
// },
// {
// "Confidence": 0.021463459357619286,
// "Type": "FEAR"
// },
// {
// "Confidence": 0.013858155347406864,
// "Type": "ANGRY"
// }
// ],
// "Eyeglasses": {
// "Confidence": 98.5116195678711,
// "Value": false
// },
// "EyesOpen": {
// "Confidence": 99.65477752685547,
// "Value": true
// },
// "Gender": {
// "Confidence": 97.1164321899414,
// "Value": "Female"
// },
// "Landmarks": [
// {
// "Type": "eyeLeft",
// "X": 0.6554790735244751,
// "Y": 0.35153862833976746
// },
// {
// "Type": "eyeRight",
// "X": 0.7940073609352112,
// "Y": 0.38292214274406433
// },
// {
// "Type": "mouthLeft",
// "X": 0.6188991069793701,
// "Y": 0.46431097388267517
// },
// {
// "Type": "mouthRight",
// "X": 0.7352844476699829,
// "Y": 0.490242063999176
// },
// {
// "Type": "nose",
// "X": 0.7125006914138794,
// "Y": 0.44607019424438477
// },
// {
// "Type": "leftEyeBrowLeft",
// "X": 0.6096581220626831,
// "Y": 0.3071737587451935
// },
// {
// "Type": "leftEyeBrowRight",
// "X": 0.6628581285476685,
// "Y": 0.3133310079574585
// },
// {
// "Type": "leftEyeBrowUp",
// "X": 0.7027584314346313,
// "Y": 0.33200803399086
// },
// {
// "Type": "rightEyeBrowLeft",
// "X": 0.7813941240310669,
// "Y": 0.35023579001426697
// },
// {
// "Type": "rightEyeBrowRight",
// "X": 0.8213478922843933,
// "Y": 0.34993964433670044
// },
// {
// "Type": "rightEyeBrowUp",
// "X": 0.8495538234710693,
// "Y": 0.36189284920692444
// },
// {
// "Type": "leftEyeLeft",
// "X": 0.629088282585144,
// "Y": 0.34286588430404663
// },
// {
// "Type": "leftEyeRight",
// "X": 0.6820939183235168,
// "Y": 0.3586524724960327
// },
// {
// "Type": "leftEyeUp",
// "X": 0.6580297946929932,
// "Y": 0.3468707501888275
// },
// {
// "Type": "leftEyeDown",
// "X": 0.6537532210350037,
// "Y": 0.35663917660713196
// },
// {
// "Type": "rightEyeLeft",
// "X": 0.7655976414680481,
// "Y": 0.3776427209377289
// },
// {
// "Type": "rightEyeRight",
// "X": 0.8166338801383972,
// "Y": 0.38544225692749023
// },
// {
// "Type": "rightEyeUp",
// "X": 0.7969376444816589,
// "Y": 0.37844377756118774
// },
// {
// "Type": "rightEyeDown",
// "X": 0.7909533977508545,
// "Y": 0.3877102732658386
// },
// {
// "Type": "noseLeft",
// "X": 0.6727234721183777,
// "Y": 0.44030481576919556
// },
// {
// "Type": "noseRight",
// "X": 0.7237889170646667,
// "Y": 0.45200300216674805
// },
// {
// "Type": "mouthUp",
// "X": 0.6882695555686951,
// "Y": 0.4740942418575287
// },
// {
// "Type": "mouthDown",
// "X": 0.6720560789108276,
// "Y": 0.5046101808547974
// },
// {
// "Type": "leftPupil",
// "X": 0.6554790735244751,
// "Y": 0.35153862833976746
// },
// {
// "Type": "rightPupil",
// "X": 0.7940073609352112,
// "Y": 0.38292214274406433
// },
// {
// "Type": "upperJawlineLeft",
// "X": 0.5517005324363708,
// "Y": 0.30355724692344666
// },
// {
// "Type": "midJawlineLeft",
// "X": 0.5320234894752502,
// "Y": 0.43352627754211426
// },
// {
// "Type": "chinBottom",
// "X": 0.6419994831085205,
// "Y": 0.5531964302062988
// },
// {
// "Type": "midJawlineRight",
// "X": 0.7752369046211243,
// "Y": 0.48957017064094543
// },
// {
// "Type": "upperJawlineRight",
// "X": 0.8515444397926331,
// "Y": 0.37258899211883545
// }
// ],
// "MouthOpen": {
// "Confidence": 68.26280212402344,
// "Value": false
// },
// "Mustache": {
// "Confidence": 99.73213195800781,
// "Value": false
// },
// "Pose": {
// "Pitch": -11.299633026123047,
// "Roll": 17.6924991607666,
// "Yaw": 13.582314491271973
// },
// "Quality": {
// "Brightness": 83.72581481933594,
// "Sharpness": 67.22731018066406
// },
// "Smile": {
// "Confidence": 98.4793930053711,
// "Value": true
// },
// "Sunglasses": {
// "Confidence": 99.3582992553711,
// "Value": false
// }
// }
// ]
// }
// Sample code for parsing the JSON response...
// Use the following online tool to generate parsing code from sample JSON:
// Generate Parsing Code from JSON
var ageRangeHigh = 0;
var ageRangeLow = 0;
var beardConfidence = '';
var boundingBoxHeight = '';
var boundingBoxLeft = '';
var boundingBoxTop = '';
var boundingBoxWidth = '';
var confidence = '';
var eyeglassesConfidence = '';
var eyesOpenConfidence = '';
var genderConfidence = '';
var genderValue = '';
var mouthOpenConfidence = '';
var mustacheConfidence = '';
var posePitch = '';
var poseRoll = '';
var poseYaw = '';
var qualityBrightness = '';
var qualitySharpness = '';
var smileConfidence = '';
var sunglassesConfidence = '';
var j = 0;
var countJ = 0;
var vType = '';
var x = '';
var y = '';
var i = 0;
final countI = jResp.sizeOfArray('FaceDetails');
while (i < countI) {
jResp.i = i;
ageRangeHigh = jResp.intOf('FaceDetails[i].AgeRange.High');
ageRangeLow = jResp.intOf('FaceDetails[i].AgeRange.Low');
beardConfidence = jResp.stringOf('FaceDetails[i].Beard.Confidence');
jResp.boolOf('FaceDetails[i].Beard.Value');
boundingBoxHeight = jResp.stringOf('FaceDetails[i].BoundingBox.Height');
boundingBoxLeft = jResp.stringOf('FaceDetails[i].BoundingBox.Left');
boundingBoxTop = jResp.stringOf('FaceDetails[i].BoundingBox.Top');
boundingBoxWidth = jResp.stringOf('FaceDetails[i].BoundingBox.Width');
confidence = jResp.stringOf('FaceDetails[i].Confidence');
eyeglassesConfidence = jResp.stringOf('FaceDetails[i].Eyeglasses.Confidence');
jResp.boolOf('FaceDetails[i].Eyeglasses.Value');
eyesOpenConfidence = jResp.stringOf('FaceDetails[i].EyesOpen.Confidence');
jResp.boolOf('FaceDetails[i].EyesOpen.Value');
genderConfidence = jResp.stringOf('FaceDetails[i].Gender.Confidence');
genderValue = jResp.stringOf('FaceDetails[i].Gender.Value');
mouthOpenConfidence = jResp.stringOf('FaceDetails[i].MouthOpen.Confidence');
jResp.boolOf('FaceDetails[i].MouthOpen.Value');
mustacheConfidence = jResp.stringOf('FaceDetails[i].Mustache.Confidence');
jResp.boolOf('FaceDetails[i].Mustache.Value');
posePitch = jResp.stringOf('FaceDetails[i].Pose.Pitch');
poseRoll = jResp.stringOf('FaceDetails[i].Pose.Roll');
poseYaw = jResp.stringOf('FaceDetails[i].Pose.Yaw');
qualityBrightness = jResp.stringOf('FaceDetails[i].Quality.Brightness');
qualitySharpness = jResp.stringOf('FaceDetails[i].Quality.Sharpness');
smileConfidence = jResp.stringOf('FaceDetails[i].Smile.Confidence');
jResp.boolOf('FaceDetails[i].Smile.Value');
sunglassesConfidence = jResp.stringOf('FaceDetails[i].Sunglasses.Confidence');
jResp.boolOf('FaceDetails[i].Sunglasses.Value');
j = 0;
countJ = jResp.sizeOfArray('FaceDetails[i].Emotions');
while (j < countJ) {
jResp.j = j;
confidence = jResp.stringOf('FaceDetails[i].Emotions[j].Confidence');
vType = jResp.stringOf('FaceDetails[i].Emotions[j].Type');
j++;
}
j = 0;
countJ = jResp.sizeOfArray('FaceDetails[i].Landmarks');
while (j < countJ) {
jResp.j = j;
vType = jResp.stringOf('FaceDetails[i].Landmarks[j].Type');
x = jResp.stringOf('FaceDetails[i].Landmarks[j].X');
y = jResp.stringOf('FaceDetails[i].Landmarks[j].Y');
j++;
}
i++;
}
}