(C) Google Cloud Vision Text Detection

Demonstrates calling the Google Cloud Vision for text detection (performs Optical Character Recognition). "Detects and extracts text within an image with support for a broad range of languages. It also features automatic language identification." See https://cloud.google.com/vision/docs/detecting-text

Note: This example requires Chilkat v11.0.0 or greater.

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#include <C_CkBinData.h>
#include <C_CkJsonObject.h>
#include <C_CkHttp.h>
#include <C_CkStringBuilder.h>
#include <C_CkHttpResponse.h>

void ChilkatSample(void)
    {
    BOOL success;
    HCkBinData imageData;
    HCkJsonObject json;
    HCkHttp http;
    HCkStringBuilder sb;
    const char *url;
    HCkHttpResponse resp;
    HCkStringBuilder sbResponseBody;
    int i;
    int count_i;
    const char *fullTextAnnotationText;
    int j;
    int count_j;
    const char *locale;
    const char *description;
    int k;
    int count_k;
    int x;
    int y;
    int width;
    int height;
    const char *languageCode;
    const char *blockType;
    int i1;
    int count_i1;
    int j1;
    int count_j1;
    int k1;
    int count_k1;
    const char *text;
    const char *propertyDetectedBreakType;
    int i2;
    int count_i2;
    HCkJsonObject json1;
    HCkJsonObject json2;

    success = FALSE;

    // This example requires the Chilkat API to have been previously unlocked.
    // See Global Unlock Sample for sample code.

    // Build the following request:

    // {
    //   "requests": [
    //     {
    //       "image": {
    //         "content": "/9j/7QBEUGhvdG9zaG9...base64-encoded-image-content...fXNWzvDEeYxxxzj/Coa6Bax//Z"
    //       },
    //       "features": [
    //         {
    //           "type": "TEXT_DETECTION"
    //         }
    //       ]
    //     }
    //   ]
    // }

    // Use this online tool to generate the code from sample JSON: 
    // Generate Code to Create JSON

    // Load an image file.
    imageData = CkBinData_Create();
    // This image file contains some text...
    success = CkBinData_LoadFile(imageData,"qa_data/jpg/text.jpg");
    if (success != TRUE) {
        printf("Failed to load image file.\n");
        CkBinData_Dispose(imageData);
        return;
    }

    // Create the above JSON.
    json = CkJsonObject_Create();
    CkJsonObject_UpdateBd(json,"requests[0].image.content","base64",imageData);
    CkJsonObject_UpdateString(json,"requests[0].features[0].type","TEXT_DETECTION");

    // Send the following POST with the HTTP request body containing the above JSON.
    // POST https://vision.googleapis.com/v1/images:annotate?key=YOUR_API_KEY

    http = CkHttp_Create();
    CkHttp_putSessionLogFilename(http,"c:/aaworkarea/sessionLog.txt");

    sb = CkStringBuilder_Create();
    url = "https://vision.googleapis.com/v1/images:annotate?key=YOUR_API_KEY";
    resp = CkHttpResponse_Create();
    success = CkHttp_HttpJson(http,"POST",url,json,"application/json",resp);
    if (success == FALSE) {
        printf("%s\n",CkHttp_lastErrorText(http));
        CkBinData_Dispose(imageData);
        CkJsonObject_Dispose(json);
        CkHttp_Dispose(http);
        CkStringBuilder_Dispose(sb);
        CkHttpResponse_Dispose(resp);
        return;
    }

    printf("status = %d\n",CkHttpResponse_getStatusCode(resp));

    // A 200 response status indicate success.
    if (CkHttpResponse_getStatusCode(resp) != 200) {
        printf("%s\n",CkHttpResponse_bodyStr(resp));
        printf("Failed.\n");
        CkBinData_Dispose(imageData);
        CkJsonObject_Dispose(json);
        CkHttp_Dispose(http);
        CkStringBuilder_Dispose(sb);
        CkHttpResponse_Dispose(resp);
        return;
    }

    sbResponseBody = CkStringBuilder_Create();
    CkHttpResponse_GetBodySb(resp,sbResponseBody);
    CkStringBuilder_WriteFile(sbResponseBody,"qa_output/textDetectResponse.json","utf-8",FALSE);
    CkJsonObject_LoadSb(json,sbResponseBody);

    // The response is a JSON document like this:

    // Use this online tool to generate parsing code from sample JSON: 
    // Generate Parsing Code from JSON

    // {
    //   "responses": [
    //     {
    //       "textAnnotations": [
    //         {
    //           "locale": "en",
    //           "description": "Chilkat is a cross-language, cross-platform\nAPl providing 90+ classes for many Internet\nprotocols, formats, and algorithms.\n",
    //           "boundingPoly": {
    //             "vertices": [
    //               {
    //                 "x": 17,
    //                 "y": 14
    //               },
    // 	...
    //             ]
    //           }
    //         ],
    //         "text": "Chilkat is a cross-language, cross-platform\nAPl providing 90+ classes for many Internet\nprotocols, formats, and algorithms.\n"
    //       }
    //     }
    //   ]
    // }

    // The parsing code generated from the online tool:

    json1 = CkJsonObject_Create();
    json2 = CkJsonObject_Create();

    i = 0;
    count_i = CkJsonObject_SizeOfArray(json,"responses");
    while (i < count_i) {
        CkJsonObject_putI(json,i);
        fullTextAnnotationText = CkJsonObject_stringOf(json,"responses[i].fullTextAnnotation.text");
        j = 0;
        count_j = CkJsonObject_SizeOfArray(json,"responses[i].textAnnotations");
        while (j < count_j) {
            CkJsonObject_putJ(json,j);
            locale = CkJsonObject_stringOf(json,"responses[i].textAnnotations[j].locale");
            description = CkJsonObject_stringOf(json,"responses[i].textAnnotations[j].description");
            k = 0;
            count_k = CkJsonObject_SizeOfArray(json,"responses[i].textAnnotations[j].boundingPoly.vertices");
            while (k < count_k) {
                CkJsonObject_putK(json,k);
                x = CkJsonObject_IntOf(json,"responses[i].textAnnotations[j].boundingPoly.vertices[k].x");
                y = CkJsonObject_IntOf(json,"responses[i].textAnnotations[j].boundingPoly.vertices[k].y");
                k = k + 1;
            }

            j = j + 1;
        }

        j = 0;
        count_j = CkJsonObject_SizeOfArray(json,"responses[i].fullTextAnnotation.pages");
        while (j < count_j) {
            CkJsonObject_putJ(json,j);
            width = CkJsonObject_IntOf(json,"responses[i].fullTextAnnotation.pages[j].width");
            height = CkJsonObject_IntOf(json,"responses[i].fullTextAnnotation.pages[j].height");
            k = 0;
            count_k = CkJsonObject_SizeOfArray(json,"responses[i].fullTextAnnotation.pages[j].property.detectedLanguages");
            while (k < count_k) {
                CkJsonObject_putK(json,k);
                languageCode = CkJsonObject_stringOf(json,"responses[i].fullTextAnnotation.pages[j].property.detectedLanguages[k].languageCode");
                k = k + 1;
            }

            k = 0;
            count_k = CkJsonObject_SizeOfArray(json,"responses[i].fullTextAnnotation.pages[j].blocks");
            while (k < count_k) {
                CkJsonObject_putK(json,k);
                blockType = CkJsonObject_stringOf(json,"responses[i].fullTextAnnotation.pages[j].blocks[k].blockType");
                CkJsonObject_ObjectOf2(json,"responses[i].fullTextAnnotation.pages[j].blocks[k]",json1);

                i1 = 0;
                count_i1 = CkJsonObject_SizeOfArray(json1,"property.detectedLanguages");
                while (i1 < count_i1) {
                    CkJsonObject_putI(json1,i1);
                    languageCode = CkJsonObject_stringOf(json1,"property.detectedLanguages[i].languageCode");
                    i1 = i1 + 1;
                }

                CkJsonObject_ObjectOf2(json,"responses[i].fullTextAnnotation.pages[j].blocks[k]",json1);

                i1 = 0;
                count_i1 = CkJsonObject_SizeOfArray(json1,"boundingBox.vertices");
                while (i1 < count_i1) {
                    CkJsonObject_putI(json1,i1);
                    x = CkJsonObject_IntOf(json1,"boundingBox.vertices[i].x");
                    y = CkJsonObject_IntOf(json1,"boundingBox.vertices[i].y");
                    i1 = i1 + 1;
                }

                CkJsonObject_ObjectOf2(json,"responses[i].fullTextAnnotation.pages[j].blocks[k]",json1);

                i1 = 0;
                count_i1 = CkJsonObject_SizeOfArray(json1,"paragraphs");
                while (i1 < count_i1) {
                    CkJsonObject_putI(json1,i1);
                    j1 = 0;
                    count_j1 = CkJsonObject_SizeOfArray(json1,"paragraphs[i].property.detectedLanguages");
                    while (j1 < count_j1) {
                        CkJsonObject_putJ(json1,j1);
                        languageCode = CkJsonObject_stringOf(json1,"paragraphs[i].property.detectedLanguages[j].languageCode");
                        j1 = j1 + 1;
                    }

                    j1 = 0;
                    count_j1 = CkJsonObject_SizeOfArray(json1,"paragraphs[i].boundingBox.vertices");
                    while (j1 < count_j1) {
                        CkJsonObject_putJ(json1,j1);
                        x = CkJsonObject_IntOf(json1,"paragraphs[i].boundingBox.vertices[j].x");
                        y = CkJsonObject_IntOf(json1,"paragraphs[i].boundingBox.vertices[j].y");
                        j1 = j1 + 1;
                    }

                    j1 = 0;
                    count_j1 = CkJsonObject_SizeOfArray(json1,"paragraphs[i].words");
                    while (j1 < count_j1) {
                        CkJsonObject_putJ(json1,j1);
                        k1 = 0;
                        count_k1 = CkJsonObject_SizeOfArray(json1,"paragraphs[i].words[j].property.detectedLanguages");
                        while (k1 < count_k1) {
                            CkJsonObject_putK(json1,k1);
                            languageCode = CkJsonObject_stringOf(json1,"paragraphs[i].words[j].property.detectedLanguages[k].languageCode");
                            k1 = k1 + 1;
                        }

                        k1 = 0;
                        count_k1 = CkJsonObject_SizeOfArray(json1,"paragraphs[i].words[j].boundingBox.vertices");
                        while (k1 < count_k1) {
                            CkJsonObject_putK(json1,k1);
                            x = CkJsonObject_IntOf(json1,"paragraphs[i].words[j].boundingBox.vertices[k].x");
                            y = CkJsonObject_IntOf(json1,"paragraphs[i].words[j].boundingBox.vertices[k].y");
                            k1 = k1 + 1;
                        }

                        k1 = 0;
                        count_k1 = CkJsonObject_SizeOfArray(json1,"paragraphs[i].words[j].symbols");
                        while (k1 < count_k1) {
                            CkJsonObject_putK(json1,k1);
                            text = CkJsonObject_stringOf(json1,"paragraphs[i].words[j].symbols[k].text");
                            propertyDetectedBreakType = CkJsonObject_stringOf(json1,"paragraphs[i].words[j].symbols[k].property.detectedBreak.type");
                            CkJsonObject_ObjectOf2(json1,"paragraphs[i].words[j].symbols[k]",json2);

                            i2 = 0;
                            count_i2 = CkJsonObject_SizeOfArray(json2,"property.detectedLanguages");
                            while (i2 < count_i2) {
                                CkJsonObject_putI(json2,i2);
                                languageCode = CkJsonObject_stringOf(json2,"property.detectedLanguages[i].languageCode");
                                i2 = i2 + 1;
                            }

                            CkJsonObject_ObjectOf2(json1,"paragraphs[i].words[j].symbols[k]",json2);

                            i2 = 0;
                            count_i2 = CkJsonObject_SizeOfArray(json2,"boundingBox.vertices");
                            while (i2 < count_i2) {
                                CkJsonObject_putI(json2,i2);
                                x = CkJsonObject_IntOf(json2,"boundingBox.vertices[i].x");
                                y = CkJsonObject_IntOf(json2,"boundingBox.vertices[i].y");
                                i2 = i2 + 1;
                            }

                            k1 = k1 + 1;
                        }

                        j1 = j1 + 1;
                    }

                    i1 = i1 + 1;
                }

                k = k + 1;
            }

            j = j + 1;
        }

        i = i + 1;
    }

    printf("Success.\n");


    CkBinData_Dispose(imageData);
    CkJsonObject_Dispose(json);
    CkHttp_Dispose(http);
    CkStringBuilder_Dispose(sb);
    CkHttpResponse_Dispose(resp);
    CkStringBuilder_Dispose(sbResponseBody);
    CkJsonObject_Dispose(json1);
    CkJsonObject_Dispose(json2);

    }