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Zig

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 Zig Downloads

Zig
const std = @import("std");
const chilkat = @import("chilkat");

pub fn main(init: std.process.Init) !void {
    const alloc = init.arena.allocator();

    const rest = try chilkat.Rest.init();
    defer rest.deinit();

    const auth_aws = try chilkat.AuthAws.init();
    defer auth_aws.deinit();
    auth_aws.setAccessKey("AWS_ACCESS_KEY");
    auth_aws.setSecretKey("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.)
    auth_aws.setRegion("us-west-2");
    auth_aws.setServiceName("rekognition");
    // SetAuthAws causes Chilkat to automatically add the following headers: Authorization, X-Amz-Date
    rest.setAuthAws(auth_aws) catch {};

    // URL: https://rekognition.us-west-2.amazonaws.com/
    const b_tls = true;
    const port = 443;
    const b_auto_reconnect = true;
    // Don't forget to change the region domain (us-west-2.amazonaws.com) to your particular region.
    rest.connect("rekognition.us-west-2.amazonaws.com", port, b_tls, b_auto_reconnect) catch {
        std.debug.print("ConnectFailReason: {d}\n", .{rest.getConnectFailReason()});
        std.debug.print("{s}\n", .{try rest.getLastErrorText(alloc)});
        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.
    const bd_jpg = try chilkat.BinData.init();
    defer bd_jpg.deinit();
    bd_jpg.loadFile("qa_data/jpg/kid_blue_coat.jpg") catch {
        std.debug.print("Failed to load the input JPG file.\n", .{});
        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.
    const sb_jpg = try chilkat.StringBuilder.init();
    defer sb_jpg.deinit();
    bd_jpg.getEncodedSb("base64", sb_jpg) catch {};

    const json = try chilkat.JsonObject.init();
    defer json.deinit();
    json.updateSb("Image.Bytes", sb_jpg) catch {};
    json.updateString("Attributes[0]", "ALL") catch {};

    rest.addHeader("Content-Type", "application/x-amz-json-1.1") catch {};
    rest.addHeader("X-Amz-Target", "RekognitionService.DetectFaces") catch {};

    const sb_request_body = try chilkat.StringBuilder.init();
    defer sb_request_body.deinit();
    json.emitSb(sb_request_body) catch {};
    const sb_response_body = try chilkat.StringBuilder.init();
    defer sb_response_body.deinit();
    rest.fullRequestSb("POST", "/", sb_request_body, sb_response_body) catch {
        std.debug.print("{s}\n", .{try rest.getLastErrorText(alloc)});
        return;
    };

    const resp_status_code = rest.getResponseStatusCode();
    std.debug.print("response status code = {d}\n", .{resp_status_code});

    if (resp_status_code >= 400) {
        std.debug.print("Response Status Code = {d}\n", .{resp_status_code});
        std.debug.print("Response Header:\n", .{});
        std.debug.print("{s}\n", .{try rest.getResponseHeader(alloc)});
        std.debug.print("Response Body:\n", .{});
        std.debug.print("{s}\n", .{try sb_response_body.getAsString(alloc)});
        return;
    }

    const j_resp = try chilkat.JsonObject.init();
    defer j_resp.deinit();
    j_resp.loadSb(sb_response_body) catch {};

    j_resp.setEmitCompact(false);
    std.debug.print("{s}\n", .{try j_resp.emit(alloc)});

    // 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 age_range_high: i32 = 0;
    var age_range_low: i32 = 0;
    var beard_confidence: [:0]const u8 = "";
    var beard_value: bool = false;
    var bounding_box_height: [:0]const u8 = "";
    var bounding_box_left: [:0]const u8 = "";
    var bounding_box_top: [:0]const u8 = "";
    var bounding_box_width: [:0]const u8 = "";
    var confidence: [:0]const u8 = "";
    var eyeglasses_confidence: [:0]const u8 = "";
    var eyeglasses_value: bool = false;
    var eyes_open_confidence: [:0]const u8 = "";
    var eyes_open_value: bool = false;
    var gender_confidence: [:0]const u8 = "";
    var gender_value: [:0]const u8 = "";
    var mouth_open_confidence: [:0]const u8 = "";
    var mouth_open_value: bool = false;
    var mustache_confidence: [:0]const u8 = "";
    var mustache_value: bool = false;
    var pose_pitch: [:0]const u8 = "";
    var pose_roll: [:0]const u8 = "";
    var pose_yaw: [:0]const u8 = "";
    var quality_brightness: [:0]const u8 = "";
    var quality_sharpness: [:0]const u8 = "";
    var smile_confidence: [:0]const u8 = "";
    var smile_value: bool = false;
    var sunglasses_confidence: [:0]const u8 = "";
    var sunglasses_value: bool = false;
    var j: i32 = 0;
    var count_j: i32 = 0;
    var v_type: [:0]const u8 = "";
    var x: [:0]const u8 = "";
    var y: [:0]const u8 = "";

    var i: i32 = 0;
    const count_i = j_resp.sizeOfArray("FaceDetails");
    while (i < count_i) {
        j_resp.setI(i);
        age_range_high = j_resp.intOf("FaceDetails[i].AgeRange.High");
        age_range_low = j_resp.intOf("FaceDetails[i].AgeRange.Low");
        beard_confidence = try j_resp.stringOf(alloc, "FaceDetails[i].Beard.Confidence");
        beard_value = j_resp.boolOf("FaceDetails[i].Beard.Value");
        bounding_box_height = try j_resp.stringOf(alloc, "FaceDetails[i].BoundingBox.Height");
        bounding_box_left = try j_resp.stringOf(alloc, "FaceDetails[i].BoundingBox.Left");
        bounding_box_top = try j_resp.stringOf(alloc, "FaceDetails[i].BoundingBox.Top");
        bounding_box_width = try j_resp.stringOf(alloc, "FaceDetails[i].BoundingBox.Width");
        confidence = try j_resp.stringOf(alloc, "FaceDetails[i].Confidence");
        eyeglasses_confidence = try j_resp.stringOf(alloc, "FaceDetails[i].Eyeglasses.Confidence");
        eyeglasses_value = j_resp.boolOf("FaceDetails[i].Eyeglasses.Value");
        eyes_open_confidence = try j_resp.stringOf(alloc, "FaceDetails[i].EyesOpen.Confidence");
        eyes_open_value = j_resp.boolOf("FaceDetails[i].EyesOpen.Value");
        gender_confidence = try j_resp.stringOf(alloc, "FaceDetails[i].Gender.Confidence");
        gender_value = try j_resp.stringOf(alloc, "FaceDetails[i].Gender.Value");
        mouth_open_confidence = try j_resp.stringOf(alloc, "FaceDetails[i].MouthOpen.Confidence");
        mouth_open_value = j_resp.boolOf("FaceDetails[i].MouthOpen.Value");
        mustache_confidence = try j_resp.stringOf(alloc, "FaceDetails[i].Mustache.Confidence");
        mustache_value = j_resp.boolOf("FaceDetails[i].Mustache.Value");
        pose_pitch = try j_resp.stringOf(alloc, "FaceDetails[i].Pose.Pitch");
        pose_roll = try j_resp.stringOf(alloc, "FaceDetails[i].Pose.Roll");
        pose_yaw = try j_resp.stringOf(alloc, "FaceDetails[i].Pose.Yaw");
        quality_brightness = try j_resp.stringOf(alloc, "FaceDetails[i].Quality.Brightness");
        quality_sharpness = try j_resp.stringOf(alloc, "FaceDetails[i].Quality.Sharpness");
        smile_confidence = try j_resp.stringOf(alloc, "FaceDetails[i].Smile.Confidence");
        smile_value = j_resp.boolOf("FaceDetails[i].Smile.Value");
        sunglasses_confidence = try j_resp.stringOf(alloc, "FaceDetails[i].Sunglasses.Confidence");
        sunglasses_value = j_resp.boolOf("FaceDetails[i].Sunglasses.Value");
        j = 0;
        count_j = j_resp.sizeOfArray("FaceDetails[i].Emotions");
        while (j < count_j) {
            j_resp.setJ(j);
            confidence = try j_resp.stringOf(alloc, "FaceDetails[i].Emotions[j].Confidence");
            v_type = try j_resp.stringOf(alloc, "FaceDetails[i].Emotions[j].Type");
            j = j + 1;
        }

        j = 0;
        count_j = j_resp.sizeOfArray("FaceDetails[i].Landmarks");
        while (j < count_j) {
            j_resp.setJ(j);
            v_type = try j_resp.stringOf(alloc, "FaceDetails[i].Landmarks[j].Type");
            x = try j_resp.stringOf(alloc, "FaceDetails[i].Landmarks[j].X");
            y = try j_resp.stringOf(alloc, "FaceDetails[i].Landmarks[j].Y");
            j = j + 1;
        }

        i = i + 1;
    }
}