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Swift

Amazon Rekognition - Detect Text in an Image

See more Amazon Rekognition Examples

Detects text in the input image and converts it into machine-readable text. This example passes theimage as base64-encoded image bytes.

Chilkat Swift Downloads

Swift

func chilkatTest() {
    var success: Bool = false

    let rest = CkoRest()!

    let authAws = CkoAuthAws()!
    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(authProvider: authAws)

    // URL: https://rekognition.us-west-2.amazonaws.com/
    var bTls: Bool = true
    var port: Int = 443
    var bAutoReconnect: Bool = true
    // Don't forget to change the region domain (us-west-2.amazonaws.com) to your particular region.
    success = rest.connect(hostname: "rekognition.us-west-2.amazonaws.com", port: port, tls: bTls, autoReconnect: bAutoReconnect)
    if success != true {
        print("ConnectFailReason: \(rest.connectFailReason.intValue)")
        print("\(rest.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.
    let bdJpg = CkoBinData()!
    success = bdJpg.loadFile(path: "qa_data/jpg/monday_keep_smiling.jpg")
    if success != true {
        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"
    //   }
    // }

    // Here is the image we used for testing:
    // (image:https://example-code.com/images/monday_keep_smiling.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.
    let sbJpg = CkoStringBuilder()!
    bdJpg.getEncodedSb(encoding: "base64", sb: sbJpg)

    let json = CkoJsonObject()!
    json.updateSb(jsonPath: "Image.Bytes", sb: sbJpg)

    rest.addHeader(name: "Content-Type", value: "application/x-amz-json-1.1")
    rest.addHeader(name: "X-Amz-Target", value: "RekognitionService.DetectText")

    let sbRequestBody = CkoStringBuilder()!
    json.emitSb(sb: sbRequestBody)
    let sbResponseBody = CkoStringBuilder()!
    success = rest.fullRequestSb(httpVerb: "POST", uriPath: "/", requestBody: sbRequestBody, responseBody: sbResponseBody)
    if success != true {
        print("\(rest.lastErrorText!)")
        return
    }

    var respStatusCode: Int = rest.responseStatusCode.intValue
    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
    }

    let jResp = CkoJsonObject()!
    jResp.loadSb(sb: sbResponseBody)

    jResp.emitCompact = false
    print("\(jResp.emit()!)")

    // Sample JSON response:
    // (Sample code for parsing the JSON response is shown below)

    // {
    //   "TextDetections": [
    //     {
    //       "Confidence": 95.99308776855469,
    //       "DetectedText": "( MONDAY IT'S",
    //       "Geometry": {
    //         "BoundingBox": {
    //           "Height": 0.6399821043014526,
    //           "Left": 0.219133198261261,
    //           "Top": 0.08677978068590164,
    //           "Width": 0.7433173656463623
    //         },
    //         "Polygon": [
    //           {
    //             "X": 0.219133198261261,
    //             "Y": 0.3588336706161499
    //           },
    //           {
    //             "X": 0.8984103798866272,
    //             "Y": 0.08677978068590164
    //           },
    //           {
    //             "X": 0.9624505639076233,
    //             "Y": 0.4547080099582672
    //           },
    //           {
    //             "X": 0.2831733524799347,
    //             "Y": 0.7267619371414185
    //           }
    //         ]
    //       },
    //       "Id": 0,
    //       "Type": "LINE"
    //     },
    //     {
    //       "Confidence": 99.70352172851562,
    //       "DetectedText": "but keep",
    //       "Geometry": {
    //         "BoundingBox": {
    //           "Height": 0.09703556448221207,
    //           "Left": 0.6335319876670837,
    //           "Top": 0.5153074264526367,
    //           "Width": 0.21070890128612518
    //         },
    //         "Polygon": [
    //           {
    //             "X": 0.6355597376823425,
    //             "Y": 0.5153074264526367
    //           },
    //           {
    //             "X": 0.8442409038543701,
    //             "Y": 0.5266726613044739
    //           },
    //           {
    //             "X": 0.8422132134437561,
    //             "Y": 0.6123430132865906
    //           },
    //           {
    //             "X": 0.6335319876670837,
    //             "Y": 0.6009777784347534
    //           }
    //         ]
    //       },
    //       "Id": 1,
    //       "Type": "LINE"
    //     },
    //     {
    //       "Confidence": 99.92333984375,
    //       "DetectedText": "Smiling",
    //       "Geometry": {
    //         "BoundingBox": {
    //           "Height": 0.31578224897384644,
    //           "Left": 0.5070608258247375,
    //           "Top": 0.6086956262588501,
    //           "Width": 0.4795433282852173
    //         },
    //         "Polygon": [
    //           {
    //             "X": 0.5070608258247375,
    //             "Y": 0.6298336386680603
    //           },
    //           {
    //             "X": 0.9808917045593262,
    //             "Y": 0.6086956262588501
    //           },
    //           {
    //             "X": 0.9866041541099548,
    //             "Y": 0.9033399224281311
    //           },
    //           {
    //             "X": 0.5127732157707214,
    //             "Y": 0.9244779348373413
    //           }
    //         ]
    //       },
    //       "Id": 2,
    //       "Type": "LINE"
    //     },
    //     {
    //       "Confidence": 99.77294158935547,
    //       "DetectedText": "IT'S",
    //       "Geometry": {
    //         "BoundingBox": {
    //           "Height": 0.09903381764888763,
    //           "Left": 0.668789803981781,
    //           "Top": 0.17874395847320557,
    //           "Width": 0.1449044644832611
    //         },
    //         "Polygon": [
    //           {
    //             "X": 0.668789803981781,
    //             "Y": 0.17874395847320557
    //           },
    //           {
    //             "X": 0.8136942386627197,
    //             "Y": 0.17874395847320557
    //           },
    //           {
    //             "X": 0.8136942386627197,
    //             "Y": 0.2777777910232544
    //           },
    //           {
    //             "X": 0.668789803981781,
    //             "Y": 0.2777777910232544
    //           }
    //         ]
    //       },
    //       "Id": 5,
    //       "ParentId": 0,
    //       "Type": "WORD"
    //     },
    //     {
    //       "Confidence": 98.44307708740234,
    //       "DetectedText": "MONDAY",
    //       "Geometry": {
    //         "BoundingBox": {
    //           "Height": 0.11112251877784729,
    //           "Left": 0.5541401505470276,
    //           "Top": 0.3526569902896881,
    //           "Width": 0.39013487100601196
    //         },
    //         "Polygon": [
    //           {
    //             "X": 0.5541401505470276,
    //             "Y": 0.3526569902896881
    //           },
    //           {
    //             "X": 0.9442675113677979,
    //             "Y": 0.3502415418624878
    //           },
    //           {
    //             "X": 0.9458598494529724,
    //             "Y": 0.4613526463508606
    //           },
    //           {
    //             "X": 0.5541401505470276,
    //             "Y": 0.4637681245803833
    //           }
    //         ]
    //       },
    //       "Id": 4,
    //       "ParentId": 0,
    //       "Type": "WORD"
    //     },
    //     {
    //       "Confidence": 99.61898803710938,
    //       "DetectedText": "but",
    //       "Geometry": {
    //         "BoundingBox": {
    //           "Height": 0.06521739065647125,
    //           "Left": 0.6353503465652466,
    //           "Top": 0.5241546034812927,
    //           "Width": 0.0843949019908905
    //         },
    //         "Polygon": [
    //           {
    //             "X": 0.6353503465652466,
    //             "Y": 0.5241546034812927
    //           },
    //           {
    //             "X": 0.7197452187538147,
    //             "Y": 0.5241546034812927
    //           },
    //           {
    //             "X": 0.7197452187538147,
    //             "Y": 0.5893719792366028
    //           },
    //           {
    //             "X": 0.6353503465652466,
    //             "Y": 0.5893719792366028
    //           }
    //         ]
    //       },
    //       "Id": 6,
    //       "ParentId": 1,
    //       "Type": "WORD"
    //     },
    //     {
    //       "Confidence": 99.78804779052734,
    //       "DetectedText": "keep",
    //       "Geometry": {
    //         "BoundingBox": {
    //           "Height": 0.07971014827489853,
    //           "Left": 0.7308917045593262,
    //           "Top": 0.5265700221061707,
    //           "Width": 0.1114649698138237
    //         },
    //         "Polygon": [
    //           {
    //             "X": 0.7308917045593262,
    //             "Y": 0.5265700221061707
    //           },
    //           {
    //             "X": 0.8423566818237305,
    //             "Y": 0.5265700221061707
    //           },
    //           {
    //             "X": 0.8423566818237305,
    //             "Y": 0.6062802076339722
    //           },
    //           {
    //             "X": 0.7308917045593262,
    //             "Y": 0.6062802076339722
    //           }
    //         ]
    //       },
    //       "Id": 7,
    //       "ParentId": 1,
    //       "Type": "WORD"
    //     },
    //     {
    //       "Confidence": 89.76324462890625,
    //       "DetectedText": "(",
    //       "Geometry": {
    //         "BoundingBox": {
    //           "Height": 0.16401274502277374,
    //           "Left": 0.27229300141334534,
    //           "Top": 0.6642512083053589,
    //           "Width": 0.2850286066532135
    //         },
    //         "Polygon": [
    //           {
    //             "X": 0.27229300141334534,
    //             "Y": 0.6642512083053589
    //           },
    //           {
    //             "X": 0.2707006335258484,
    //             "Y": 0.37922704219818115
    //           },
    //           {
    //             "X": 0.43471336364746094,
    //             "Y": 0.37922704219818115
    //           },
    //           {
    //             "X": 0.4363057315349579,
    //             "Y": 0.6642512083053589
    //           }
    //         ]
    //       },
    //       "Id": 3,
    //       "ParentId": 0,
    //       "Type": "WORD"
    //     },
    //     {
    //       "Confidence": 99.92333984375,
    //       "DetectedText": "Smiling",
    //       "Geometry": {
    //         "BoundingBox": {
    //           "Height": 0.294724702835083,
    //           "Left": 0.5079618096351624,
    //           "Top": 0.6304348111152649,
    //           "Width": 0.4734293222427368
    //         },
    //         "Polygon": [
    //           {
    //             "X": 0.5079618096351624,
    //             "Y": 0.6304348111152649
    //           },
    //           {
    //             "X": 0.9808917045593262,
    //             "Y": 0.6086956262588501
    //           },
    //           {
    //             "X": 0.9856687784194946,
    //             "Y": 0.9033816456794739
    //           },
    //           {
    //             "X": 0.512738823890686,
    //             "Y": 0.9227052927017212
    //           }
    //         ]
    //       },
    //       "Id": 8,
    //       "ParentId": 2,
    //       "Type": "WORD"
    //     }
    //   ],
    //   "TextModelVersion": "3.0"
    // }
    // 
    // 

    // 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 Confidence: String?
    var DetectedText: String?
    var GeometryBoundingBoxHeight: String?
    var GeometryBoundingBoxLeft: String?
    var GeometryBoundingBoxTop: String?
    var GeometryBoundingBoxWidth: String?
    var Id: Int
    var v_Type: String?
    var ParentId: Int
    var j: Int
    var count_j: Int
    var X: String?
    var Y: String?

    var TextModelVersion: String? = jResp.string(of: "TextModelVersion")
    var i: Int = 0
    var count_i: Int = jResp.size(ofArray: "TextDetections").intValue
    while i < count_i {
        jResp.i = i
        Confidence = jResp.string(of: "TextDetections[i].Confidence")
        DetectedText = jResp.string(of: "TextDetections[i].DetectedText")
        GeometryBoundingBoxHeight = jResp.string(of: "TextDetections[i].Geometry.BoundingBox.Height")
        GeometryBoundingBoxLeft = jResp.string(of: "TextDetections[i].Geometry.BoundingBox.Left")
        GeometryBoundingBoxTop = jResp.string(of: "TextDetections[i].Geometry.BoundingBox.Top")
        GeometryBoundingBoxWidth = jResp.string(of: "TextDetections[i].Geometry.BoundingBox.Width")
        Id = jResp.int(of: "TextDetections[i].Id").intValue
        v_Type = jResp.string(of: "TextDetections[i].Type")
        ParentId = jResp.int(of: "TextDetections[i].ParentId").intValue
        j = 0
        count_j = jResp.size(ofArray: "TextDetections[i].Geometry.Polygon").intValue
        while j < count_j {
            jResp.j = j
            X = jResp.string(of: "TextDetections[i].Geometry.Polygon[j].X")
            Y = jResp.string(of: "TextDetections[i].Geometry.Polygon[j].Y")
            j = j + 1
        }

        i = i + 1
    }


}