(Lianja) 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

Chilkat Lianja Extension Download Chilkat Lianja Extension

// 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.
loImageData = createobject("CkBinData")
// This image file contains some text...
llSuccess = loImageData.LoadFile("qa_data/jpg/text.jpg")
if (llSuccess <> .T.) then
    ? "Failed to load image file."
    release loImageData
    return
endif

// Create the above JSON.
loJson = createobject("CkJsonObject")
loJson.UpdateBd("requests[0].image.content","base64",loImageData)
loJson.UpdateString("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

loHttp = createobject("CkHttp")
loSb = createobject("CkStringBuilder")
lcUrl = "https://vision.googleapis.com/v1/images:annotate?key=YOUR_API_KEY"
loResp = loHttp.PostJson3(lcUrl,"application/json",loJson)
if (loHttp.LastMethodSuccess <> .T.) then
    ? loHttp.LastErrorText
    release loImageData
    release loJson
    release loHttp
    release loSb
    return
endif

? "status = " + str(loResp.StatusCode)

// A 200 response status indicate success.
if (loResp.StatusCode <> 200) then
    ? loResp.BodyStr
    ? "Failed."
    release loResp
    release loImageData
    release loJson
    release loHttp
    release loSb
    return
endif

loSbResponseBody = createobject("CkStringBuilder")
loResp.GetBodySb(loSbResponseBody)
loSbResponseBody.WriteFile("qa_output/textDetectResponse.json","utf-8",.F.)
loJson.LoadSb(loSbResponseBody)

// 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 = 0
lnCount_i = loJson.SizeOfArray("responses")
do while i < lnCount_i
    loJson.I = i
    lcFullTextAnnotationText = loJson.StringOf("responses[i].fullTextAnnotation.text")
    j = 0
    lnCount_j = loJson.SizeOfArray("responses[i].textAnnotations")
    do while j < lnCount_j
        loJson.J = j
        lcLocale = loJson.StringOf("responses[i].textAnnotations[j].locale")
        lcDescription = loJson.StringOf("responses[i].textAnnotations[j].description")
        k = 0
        lnCount_k = loJson.SizeOfArray("responses[i].textAnnotations[j].boundingPoly.vertices")
        do while k < lnCount_k
            loJson.K = k
            x = loJson.IntOf("responses[i].textAnnotations[j].boundingPoly.vertices[k].x")
            y = loJson.IntOf("responses[i].textAnnotations[j].boundingPoly.vertices[k].y")
            k = k + 1
        enddo
        j = j + 1
    enddo
    j = 0
    lnCount_j = loJson.SizeOfArray("responses[i].fullTextAnnotation.pages")
    do while j < lnCount_j
        loJson.J = j
        lnWidth = loJson.IntOf("responses[i].fullTextAnnotation.pages[j].width")
        lnHeight = loJson.IntOf("responses[i].fullTextAnnotation.pages[j].height")
        k = 0
        lnCount_k = loJson.SizeOfArray("responses[i].fullTextAnnotation.pages[j].property.detectedLanguages")
        do while k < lnCount_k
            loJson.K = k
            lcLanguageCode = loJson.StringOf("responses[i].fullTextAnnotation.pages[j].property.detectedLanguages[k].languageCode")
            k = k + 1
        enddo
        k = 0
        lnCount_k = loJson.SizeOfArray("responses[i].fullTextAnnotation.pages[j].blocks")
        do while k < lnCount_k
            loJson.K = k
            lcBlockType = loJson.StringOf("responses[i].fullTextAnnotation.pages[j].blocks[k].blockType")

            loJson1 = loJson.ObjectOf("responses[i].fullTextAnnotation.pages[j].blocks[k]")
            lnI1 = 0
            lnCount_i1 = loJson1.SizeOfArray("property.detectedLanguages")
            do while lnI1 < lnCount_i1
                loJson1.I = lnI1
                lcLanguageCode = loJson1.StringOf("property.detectedLanguages[i].languageCode")
                lnI1 = lnI1 + 1
            enddo
            release loJson1

            loJson1 = loJson.ObjectOf("responses[i].fullTextAnnotation.pages[j].blocks[k]")
            lnI1 = 0
            lnCount_i1 = loJson1.SizeOfArray("boundingBox.vertices")
            do while lnI1 < lnCount_i1
                loJson1.I = lnI1
                x = loJson1.IntOf("boundingBox.vertices[i].x")
                y = loJson1.IntOf("boundingBox.vertices[i].y")
                lnI1 = lnI1 + 1
            enddo
            release loJson1

            loJson1 = loJson.ObjectOf("responses[i].fullTextAnnotation.pages[j].blocks[k]")
            lnI1 = 0
            lnCount_i1 = loJson1.SizeOfArray("paragraphs")
            do while lnI1 < lnCount_i1
                loJson1.I = lnI1
                lnJ1 = 0
                lnCount_j1 = loJson1.SizeOfArray("paragraphs[i].property.detectedLanguages")
                do while lnJ1 < lnCount_j1
                    loJson1.J = lnJ1
                    lcLanguageCode = loJson1.StringOf("paragraphs[i].property.detectedLanguages[j].languageCode")
                    lnJ1 = lnJ1 + 1
                enddo
                lnJ1 = 0
                lnCount_j1 = loJson1.SizeOfArray("paragraphs[i].boundingBox.vertices")
                do while lnJ1 < lnCount_j1
                    loJson1.J = lnJ1
                    x = loJson1.IntOf("paragraphs[i].boundingBox.vertices[j].x")
                    y = loJson1.IntOf("paragraphs[i].boundingBox.vertices[j].y")
                    lnJ1 = lnJ1 + 1
                enddo
                lnJ1 = 0
                lnCount_j1 = loJson1.SizeOfArray("paragraphs[i].words")
                do while lnJ1 < lnCount_j1
                    loJson1.J = lnJ1
                    lnK1 = 0
                    lnCount_k1 = loJson1.SizeOfArray("paragraphs[i].words[j].property.detectedLanguages")
                    do while lnK1 < lnCount_k1
                        loJson1.K = lnK1
                        lcLanguageCode = loJson1.StringOf("paragraphs[i].words[j].property.detectedLanguages[k].languageCode")
                        lnK1 = lnK1 + 1
                    enddo
                    lnK1 = 0
                    lnCount_k1 = loJson1.SizeOfArray("paragraphs[i].words[j].boundingBox.vertices")
                    do while lnK1 < lnCount_k1
                        loJson1.K = lnK1
                        x = loJson1.IntOf("paragraphs[i].words[j].boundingBox.vertices[k].x")
                        y = loJson1.IntOf("paragraphs[i].words[j].boundingBox.vertices[k].y")
                        lnK1 = lnK1 + 1
                    enddo
                    lnK1 = 0
                    lnCount_k1 = loJson1.SizeOfArray("paragraphs[i].words[j].symbols")
                    do while lnK1 < lnCount_k1
                        loJson1.K = lnK1
                        lcText = loJson1.StringOf("paragraphs[i].words[j].symbols[k].text")
                        lcPropertyDetectedBreakType = loJson1.StringOf("paragraphs[i].words[j].symbols[k].property.detectedBreak.type")

                        loJson2 = loJson1.ObjectOf("paragraphs[i].words[j].symbols[k]")
                        lnI2 = 0
                        lnCount_i2 = loJson2.SizeOfArray("property.detectedLanguages")
                        do while lnI2 < lnCount_i2
                            loJson2.I = lnI2
                            lcLanguageCode = loJson2.StringOf("property.detectedLanguages[i].languageCode")
                            lnI2 = lnI2 + 1
                        enddo
                        release loJson2

                        loJson2 = loJson1.ObjectOf("paragraphs[i].words[j].symbols[k]")
                        lnI2 = 0
                        lnCount_i2 = loJson2.SizeOfArray("boundingBox.vertices")
                        do while lnI2 < lnCount_i2
                            loJson2.I = lnI2
                            x = loJson2.IntOf("boundingBox.vertices[i].x")
                            y = loJson2.IntOf("boundingBox.vertices[i].y")
                            lnI2 = lnI2 + 1
                        enddo
                        release loJson2
                        lnK1 = lnK1 + 1
                    enddo
                    lnJ1 = lnJ1 + 1
                enddo
                lnI1 = lnI1 + 1
            enddo
            release loJson1
            k = k + 1
        enddo
        j = j + 1
    enddo
    i = i + 1
enddo

release loResp

? "Success."


release loImageData
release loJson
release loHttp
release loSb
release loSbResponseBody