Sample code for 30+ languages & platforms
PureBasic

Google Cloud Vision Text Detection

See more HTTP Misc Examples

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

Chilkat PureBasic Downloads

PureBasic
IncludeFile "CkBinData.pb"
IncludeFile "CkHttp.pb"
IncludeFile "CkStringBuilder.pb"
IncludeFile "CkJsonObject.pb"
IncludeFile "CkHttpResponse.pb"

Procedure ChilkatExample()

    success.i = 0

    ; 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.i = CkBinData::ckCreate()
    If imageData.i = 0
        Debug "Failed to create object."
        ProcedureReturn
    EndIf

    ; This image file contains some text...
    success = CkBinData::ckLoadFile(imageData,"qa_data/jpg/text.jpg")
    If success <> 1
        Debug "Failed to load image file."
        CkBinData::ckDispose(imageData)
        ProcedureReturn
    EndIf

    ; Create the above JSON.
    json.i = CkJsonObject::ckCreate()
    If json.i = 0
        Debug "Failed to create object."
        ProcedureReturn
    EndIf

    CkJsonObject::ckUpdateBd(json,"requests[0].image.content","base64",imageData)
    CkJsonObject::ckUpdateString(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.i = CkHttp::ckCreate()
    If http.i = 0
        Debug "Failed to create object."
        ProcedureReturn
    EndIf

    CkHttp::setCkSessionLogFilename(http, "c:/aaworkarea/sessionLog.txt")

    sb.i = CkStringBuilder::ckCreate()
    If sb.i = 0
        Debug "Failed to create object."
        ProcedureReturn
    EndIf

    url.s = "https://vision.googleapis.com/v1/images:annotate?key=YOUR_API_KEY"
    resp.i = CkHttpResponse::ckCreate()
    If resp.i = 0
        Debug "Failed to create object."
        ProcedureReturn
    EndIf

    success = CkHttp::ckHttpJson(http,"POST",url,json,"application/json",resp)
    If success = 0
        Debug CkHttp::ckLastErrorText(http)
        CkBinData::ckDispose(imageData)
        CkJsonObject::ckDispose(json)
        CkHttp::ckDispose(http)
        CkStringBuilder::ckDispose(sb)
        CkHttpResponse::ckDispose(resp)
        ProcedureReturn
    EndIf

    Debug "status = " + Str(CkHttpResponse::ckStatusCode(resp))

    ; A 200 response status indicate success.
    If CkHttpResponse::ckStatusCode(resp) <> 200
        Debug CkHttpResponse::ckBodyStr(resp)
        Debug "Failed."
        CkBinData::ckDispose(imageData)
        CkJsonObject::ckDispose(json)
        CkHttp::ckDispose(http)
        CkStringBuilder::ckDispose(sb)
        CkHttpResponse::ckDispose(resp)
        ProcedureReturn
    EndIf

    sbResponseBody.i = CkStringBuilder::ckCreate()
    If sbResponseBody.i = 0
        Debug "Failed to create object."
        ProcedureReturn
    EndIf

    CkHttpResponse::ckGetBodySb(resp,sbResponseBody)
    CkStringBuilder::ckWriteFile(sbResponseBody,"qa_output/textDetectResponse.json","utf-8",0)
    CkJsonObject::ckLoadSb(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:

    i.i
    count_i.i
    fullTextAnnotationText.s
    j.i
    count_j.i
    locale.s
    description.s
    k.i
    count_k.i
    x.i
    y.i
    width.i
    height.i
    languageCode.s
    blockType.s
    i1.i
    count_i1.i
    j1.i
    count_j1.i
    k1.i
    count_k1.i
    text.s
    propertyDetectedBreakType.s
    i2.i
    count_i2.i
    json1.i = CkJsonObject::ckCreate()
    If json1.i = 0
        Debug "Failed to create object."
        ProcedureReturn
    EndIf

    json2.i = CkJsonObject::ckCreate()
    If json2.i = 0
        Debug "Failed to create object."
        ProcedureReturn
    EndIf

    i = 0
    count_i = CkJsonObject::ckSizeOfArray(json,"responses")
    While i < count_i
        CkJsonObject::setCkI(json, i)
        fullTextAnnotationText = CkJsonObject::ckStringOf(json,"responses[i].fullTextAnnotation.text")
        j = 0
        count_j = CkJsonObject::ckSizeOfArray(json,"responses[i].textAnnotations")
        While j < count_j
            CkJsonObject::setCkJ(json, j)
            locale = CkJsonObject::ckStringOf(json,"responses[i].textAnnotations[j].locale")
            description = CkJsonObject::ckStringOf(json,"responses[i].textAnnotations[j].description")
            k = 0
            count_k = CkJsonObject::ckSizeOfArray(json,"responses[i].textAnnotations[j].boundingPoly.vertices")
            While k < count_k
                CkJsonObject::setCkK(json, k)
                x = CkJsonObject::ckIntOf(json,"responses[i].textAnnotations[j].boundingPoly.vertices[k].x")
                y = CkJsonObject::ckIntOf(json,"responses[i].textAnnotations[j].boundingPoly.vertices[k].y")
                k = k + 1
            Wend
            j = j + 1
        Wend
        j = 0
        count_j = CkJsonObject::ckSizeOfArray(json,"responses[i].fullTextAnnotation.pages")
        While j < count_j
            CkJsonObject::setCkJ(json, j)
            width = CkJsonObject::ckIntOf(json,"responses[i].fullTextAnnotation.pages[j].width")
            height = CkJsonObject::ckIntOf(json,"responses[i].fullTextAnnotation.pages[j].height")
            k = 0
            count_k = CkJsonObject::ckSizeOfArray(json,"responses[i].fullTextAnnotation.pages[j].property.detectedLanguages")
            While k < count_k
                CkJsonObject::setCkK(json, k)
                languageCode = CkJsonObject::ckStringOf(json,"responses[i].fullTextAnnotation.pages[j].property.detectedLanguages[k].languageCode")
                k = k + 1
            Wend
            k = 0
            count_k = CkJsonObject::ckSizeOfArray(json,"responses[i].fullTextAnnotation.pages[j].blocks")
            While k < count_k
                CkJsonObject::setCkK(json, k)
                blockType = CkJsonObject::ckStringOf(json,"responses[i].fullTextAnnotation.pages[j].blocks[k].blockType")
                CkJsonObject::ckObjectOf2(json,"responses[i].fullTextAnnotation.pages[j].blocks[k]",json1)

                i1 = 0
                count_i1 = CkJsonObject::ckSizeOfArray(json1,"property.detectedLanguages")
                While i1 < count_i1
                    CkJsonObject::setCkI(json1, i1)
                    languageCode = CkJsonObject::ckStringOf(json1,"property.detectedLanguages[i].languageCode")
                    i1 = i1 + 1
                Wend
                CkJsonObject::ckObjectOf2(json,"responses[i].fullTextAnnotation.pages[j].blocks[k]",json1)

                i1 = 0
                count_i1 = CkJsonObject::ckSizeOfArray(json1,"boundingBox.vertices")
                While i1 < count_i1
                    CkJsonObject::setCkI(json1, i1)
                    x = CkJsonObject::ckIntOf(json1,"boundingBox.vertices[i].x")
                    y = CkJsonObject::ckIntOf(json1,"boundingBox.vertices[i].y")
                    i1 = i1 + 1
                Wend
                CkJsonObject::ckObjectOf2(json,"responses[i].fullTextAnnotation.pages[j].blocks[k]",json1)

                i1 = 0
                count_i1 = CkJsonObject::ckSizeOfArray(json1,"paragraphs")
                While i1 < count_i1
                    CkJsonObject::setCkI(json1, i1)
                    j1 = 0
                    count_j1 = CkJsonObject::ckSizeOfArray(json1,"paragraphs[i].property.detectedLanguages")
                    While j1 < count_j1
                        CkJsonObject::setCkJ(json1, j1)
                        languageCode = CkJsonObject::ckStringOf(json1,"paragraphs[i].property.detectedLanguages[j].languageCode")
                        j1 = j1 + 1
                    Wend
                    j1 = 0
                    count_j1 = CkJsonObject::ckSizeOfArray(json1,"paragraphs[i].boundingBox.vertices")
                    While j1 < count_j1
                        CkJsonObject::setCkJ(json1, j1)
                        x = CkJsonObject::ckIntOf(json1,"paragraphs[i].boundingBox.vertices[j].x")
                        y = CkJsonObject::ckIntOf(json1,"paragraphs[i].boundingBox.vertices[j].y")
                        j1 = j1 + 1
                    Wend
                    j1 = 0
                    count_j1 = CkJsonObject::ckSizeOfArray(json1,"paragraphs[i].words")
                    While j1 < count_j1
                        CkJsonObject::setCkJ(json1, j1)
                        k1 = 0
                        count_k1 = CkJsonObject::ckSizeOfArray(json1,"paragraphs[i].words[j].property.detectedLanguages")
                        While k1 < count_k1
                            CkJsonObject::setCkK(json1, k1)
                            languageCode = CkJsonObject::ckStringOf(json1,"paragraphs[i].words[j].property.detectedLanguages[k].languageCode")
                            k1 = k1 + 1
                        Wend
                        k1 = 0
                        count_k1 = CkJsonObject::ckSizeOfArray(json1,"paragraphs[i].words[j].boundingBox.vertices")
                        While k1 < count_k1
                            CkJsonObject::setCkK(json1, k1)
                            x = CkJsonObject::ckIntOf(json1,"paragraphs[i].words[j].boundingBox.vertices[k].x")
                            y = CkJsonObject::ckIntOf(json1,"paragraphs[i].words[j].boundingBox.vertices[k].y")
                            k1 = k1 + 1
                        Wend
                        k1 = 0
                        count_k1 = CkJsonObject::ckSizeOfArray(json1,"paragraphs[i].words[j].symbols")
                        While k1 < count_k1
                            CkJsonObject::setCkK(json1, k1)
                            text = CkJsonObject::ckStringOf(json1,"paragraphs[i].words[j].symbols[k].text")
                            propertyDetectedBreakType = CkJsonObject::ckStringOf(json1,"paragraphs[i].words[j].symbols[k].property.detectedBreak.type")
                            CkJsonObject::ckObjectOf2(json1,"paragraphs[i].words[j].symbols[k]",json2)

                            i2 = 0
                            count_i2 = CkJsonObject::ckSizeOfArray(json2,"property.detectedLanguages")
                            While i2 < count_i2
                                CkJsonObject::setCkI(json2, i2)
                                languageCode = CkJsonObject::ckStringOf(json2,"property.detectedLanguages[i].languageCode")
                                i2 = i2 + 1
                            Wend
                            CkJsonObject::ckObjectOf2(json1,"paragraphs[i].words[j].symbols[k]",json2)

                            i2 = 0
                            count_i2 = CkJsonObject::ckSizeOfArray(json2,"boundingBox.vertices")
                            While i2 < count_i2
                                CkJsonObject::setCkI(json2, i2)
                                x = CkJsonObject::ckIntOf(json2,"boundingBox.vertices[i].x")
                                y = CkJsonObject::ckIntOf(json2,"boundingBox.vertices[i].y")
                                i2 = i2 + 1
                            Wend
                            k1 = k1 + 1
                        Wend
                        j1 = j1 + 1
                    Wend
                    i1 = i1 + 1
                Wend
                k = k + 1
            Wend
            j = j + 1
        Wend
        i = i + 1
    Wend

    Debug "Success."


    CkBinData::ckDispose(imageData)
    CkJsonObject::ckDispose(json)
    CkHttp::ckDispose(http)
    CkStringBuilder::ckDispose(sb)
    CkHttpResponse::ckDispose(resp)
    CkStringBuilder::ckDispose(sbResponseBody)
    CkJsonObject::ckDispose(json1)
    CkJsonObject::ckDispose(json2)


    ProcedureReturn
EndProcedure