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Unicode C++

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 Unicode C++ Downloads

Unicode C++
#include <CkRestW.h>
#include <CkAuthAwsW.h>
#include <CkBinDataW.h>
#include <CkStringBuilderW.h>
#include <CkJsonObjectW.h>

void ChilkatSample(void)
    {
    bool success = false;

    CkRestW rest;

    CkAuthAwsW authAws;
    authAws.put_AccessKey(L"AWS_ACCESS_KEY");
    authAws.put_SecretKey(L"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.put_Region(L"us-west-2");
    authAws.put_ServiceName(L"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/
    bool bTls = true;
    int port = 443;
    bool bAutoReconnect = true;
    // Don't forget to change the region domain (us-west-2.amazonaws.com) to your particular region.
    success = rest.Connect(L"rekognition.us-west-2.amazonaws.com",port,bTls,bAutoReconnect);
    if (success != true) {
        wprintf(L"ConnectFailReason: %d\n",rest.get_ConnectFailReason());
        wprintf(L"%s\n",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.
    CkBinDataW bdJpg;
    success = bdJpg.LoadFile(L"qa_data/jpg/monday_keep_smiling.jpg");
    if (success != true) {
        wprintf(L"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"
    //   }
    // }

    // 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.
    CkStringBuilderW sbJpg;
    bdJpg.GetEncodedSb(L"base64",sbJpg);

    CkJsonObjectW json;
    json.UpdateSb(L"Image.Bytes",sbJpg);

    rest.AddHeader(L"Content-Type",L"application/x-amz-json-1.1");
    rest.AddHeader(L"X-Amz-Target",L"RekognitionService.DetectText");

    CkStringBuilderW sbRequestBody;
    json.EmitSb(sbRequestBody);
    CkStringBuilderW sbResponseBody;
    success = rest.FullRequestSb(L"POST",L"/",sbRequestBody,sbResponseBody);
    if (success != true) {
        wprintf(L"%s\n",rest.lastErrorText());
        return;
    }

    int respStatusCode = rest.get_ResponseStatusCode();
    wprintf(L"response status code = %d\n",respStatusCode);

    if (respStatusCode >= 400) {
        wprintf(L"Response Status Code = %d\n",respStatusCode);
        wprintf(L"Response Header:\n");
        wprintf(L"%s\n",rest.responseHeader());
        wprintf(L"Response Body:\n");
        wprintf(L"%s\n",sbResponseBody.getAsString());
        return;
    }

    CkJsonObjectW jResp;
    jResp.LoadSb(sbResponseBody);

    jResp.put_EmitCompact(false);
    wprintf(L"%s\n",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

    // Chilkat functions returning "const char *" return a pointer to temporary internal memory owned and managed by Chilkat.
    // See this example explaining how this memory should be used: const char * functions.

    const wchar_t *Confidence = 0;
    const wchar_t *DetectedText = 0;
    const wchar_t *GeometryBoundingBoxHeight = 0;
    const wchar_t *GeometryBoundingBoxLeft = 0;
    const wchar_t *GeometryBoundingBoxTop = 0;
    const wchar_t *GeometryBoundingBoxWidth = 0;
    int Id;
    const wchar_t *v_Type = 0;
    int ParentId;
    int j;
    int count_j;
    const wchar_t *X = 0;
    const wchar_t *Y = 0;

    const wchar_t *TextModelVersion = jResp.stringOf(L"TextModelVersion");
    int i = 0;
    int count_i = jResp.SizeOfArray(L"TextDetections");
    while (i < count_i) {
        jResp.put_I(i);
        Confidence = jResp.stringOf(L"TextDetections[i].Confidence");
        DetectedText = jResp.stringOf(L"TextDetections[i].DetectedText");
        GeometryBoundingBoxHeight = jResp.stringOf(L"TextDetections[i].Geometry.BoundingBox.Height");
        GeometryBoundingBoxLeft = jResp.stringOf(L"TextDetections[i].Geometry.BoundingBox.Left");
        GeometryBoundingBoxTop = jResp.stringOf(L"TextDetections[i].Geometry.BoundingBox.Top");
        GeometryBoundingBoxWidth = jResp.stringOf(L"TextDetections[i].Geometry.BoundingBox.Width");
        Id = jResp.IntOf(L"TextDetections[i].Id");
        v_Type = jResp.stringOf(L"TextDetections[i].Type");
        ParentId = jResp.IntOf(L"TextDetections[i].ParentId");
        j = 0;
        count_j = jResp.SizeOfArray(L"TextDetections[i].Geometry.Polygon");
        while (j < count_j) {
            jResp.put_J(j);
            X = jResp.stringOf(L"TextDetections[i].Geometry.Polygon[j].X");
            Y = jResp.stringOf(L"TextDetections[i].Geometry.Polygon[j].Y");
            j = j + 1;
        }

        i = i + 1;
    }
    }