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Xojo Plugin

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 Xojo Plugin Downloads

Xojo Plugin
Dim success As Boolean
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.
Dim imageData As New Chilkat.BinData
// This image file contains some text...
success = imageData.LoadFile("qa_data/jpg/text.jpg")
If (success <> True) Then
    System.DebugLog("Failed to load image file.")
    Return
End If

// Create the above JSON.
Dim json As New Chilkat.JsonObject
success = json.UpdateBd("requests[0].image.content","base64",imageData)
success = json.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

Dim http As New Chilkat.Http
http.SessionLogFilename = "c:/aaworkarea/sessionLog.txt"

Dim sb As New Chilkat.StringBuilder
Dim url As String
url = "https://vision.googleapis.com/v1/images:annotate?key=YOUR_API_KEY"
Dim resp As New Chilkat.HttpResponse
success = http.HttpJson("POST",url,json,"application/json",resp)
If (success = False) Then
    System.DebugLog(http.LastErrorText)
    Return
End If

System.DebugLog("status = " + Str(resp.StatusCode))

// A 200 response status indicate success.
If (resp.StatusCode <> 200) Then
    System.DebugLog(resp.BodyStr)
    System.DebugLog("Failed.")
    Return
End If

Dim sbResponseBody As New Chilkat.StringBuilder
success = resp.GetBodySb(sbResponseBody)
success = sbResponseBody.WriteFile("qa_output/textDetectResponse.json","utf-8",False)
success = json.LoadSb(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:

Dim i As Int32
Dim count_i As Int32
Dim fullTextAnnotationText As String
Dim j As Int32
Dim count_j As Int32
Dim locale As String
Dim description As String
Dim k As Int32
Dim count_k As Int32
Dim x As Int32
Dim y As Int32
Dim width As Int32
Dim height As Int32
Dim languageCode As String
Dim blockType As String
Dim i1 As Int32
Dim count_i1 As Int32
Dim j1 As Int32
Dim count_j1 As Int32
Dim k1 As Int32
Dim count_k1 As Int32
Dim text As String
Dim propertyDetectedBreakType As String
Dim i2 As Int32
Dim count_i2 As Int32
Dim json1 As New Chilkat.JsonObject
Dim json2 As New Chilkat.JsonObject

i = 0
count_i = json.SizeOfArray("responses")
While i < count_i
    json.I = i
    fullTextAnnotationText = json.StringOf("responses[i].fullTextAnnotation.text")
    j = 0
    count_j = json.SizeOfArray("responses[i].textAnnotations")
    While j < count_j
        json.J = j
        locale = json.StringOf("responses[i].textAnnotations[j].locale")
        description = json.StringOf("responses[i].textAnnotations[j].description")
        k = 0
        count_k = json.SizeOfArray("responses[i].textAnnotations[j].boundingPoly.vertices")
        While k < count_k
            json.K = k
            x = json.IntOf("responses[i].textAnnotations[j].boundingPoly.vertices[k].x")
            y = json.IntOf("responses[i].textAnnotations[j].boundingPoly.vertices[k].y")
            k = k + 1
        Wend
        j = j + 1
    Wend
    j = 0
    count_j = json.SizeOfArray("responses[i].fullTextAnnotation.pages")
    While j < count_j
        json.J = j
        width = json.IntOf("responses[i].fullTextAnnotation.pages[j].width")
        height = json.IntOf("responses[i].fullTextAnnotation.pages[j].height")
        k = 0
        count_k = json.SizeOfArray("responses[i].fullTextAnnotation.pages[j].property.detectedLanguages")
        While k < count_k
            json.K = k
            languageCode = json.StringOf("responses[i].fullTextAnnotation.pages[j].property.detectedLanguages[k].languageCode")
            k = k + 1
        Wend
        k = 0
        count_k = json.SizeOfArray("responses[i].fullTextAnnotation.pages[j].blocks")
        While k < count_k
            json.K = k
            blockType = json.StringOf("responses[i].fullTextAnnotation.pages[j].blocks[k].blockType")
            success = json.ObjectOf2("responses[i].fullTextAnnotation.pages[j].blocks[k]",json1)

            i1 = 0
            count_i1 = json1.SizeOfArray("property.detectedLanguages")
            While i1 < count_i1
                json1.I = i1
                languageCode = json1.StringOf("property.detectedLanguages[i].languageCode")
                i1 = i1 + 1
            Wend
            success = json.ObjectOf2("responses[i].fullTextAnnotation.pages[j].blocks[k]",json1)

            i1 = 0
            count_i1 = json1.SizeOfArray("boundingBox.vertices")
            While i1 < count_i1
                json1.I = i1
                x = json1.IntOf("boundingBox.vertices[i].x")
                y = json1.IntOf("boundingBox.vertices[i].y")
                i1 = i1 + 1
            Wend
            success = json.ObjectOf2("responses[i].fullTextAnnotation.pages[j].blocks[k]",json1)

            i1 = 0
            count_i1 = json1.SizeOfArray("paragraphs")
            While i1 < count_i1
                json1.I = i1
                j1 = 0
                count_j1 = json1.SizeOfArray("paragraphs[i].property.detectedLanguages")
                While j1 < count_j1
                    json1.J = j1
                    languageCode = json1.StringOf("paragraphs[i].property.detectedLanguages[j].languageCode")
                    j1 = j1 + 1
                Wend
                j1 = 0
                count_j1 = json1.SizeOfArray("paragraphs[i].boundingBox.vertices")
                While j1 < count_j1
                    json1.J = j1
                    x = json1.IntOf("paragraphs[i].boundingBox.vertices[j].x")
                    y = json1.IntOf("paragraphs[i].boundingBox.vertices[j].y")
                    j1 = j1 + 1
                Wend
                j1 = 0
                count_j1 = json1.SizeOfArray("paragraphs[i].words")
                While j1 < count_j1
                    json1.J = j1
                    k1 = 0
                    count_k1 = json1.SizeOfArray("paragraphs[i].words[j].property.detectedLanguages")
                    While k1 < count_k1
                        json1.K = k1
                        languageCode = json1.StringOf("paragraphs[i].words[j].property.detectedLanguages[k].languageCode")
                        k1 = k1 + 1
                    Wend
                    k1 = 0
                    count_k1 = json1.SizeOfArray("paragraphs[i].words[j].boundingBox.vertices")
                    While k1 < count_k1
                        json1.K = k1
                        x = json1.IntOf("paragraphs[i].words[j].boundingBox.vertices[k].x")
                        y = json1.IntOf("paragraphs[i].words[j].boundingBox.vertices[k].y")
                        k1 = k1 + 1
                    Wend
                    k1 = 0
                    count_k1 = json1.SizeOfArray("paragraphs[i].words[j].symbols")
                    While k1 < count_k1
                        json1.K = k1
                        text = json1.StringOf("paragraphs[i].words[j].symbols[k].text")
                        propertyDetectedBreakType = json1.StringOf("paragraphs[i].words[j].symbols[k].property.detectedBreak.type")
                        success = json1.ObjectOf2("paragraphs[i].words[j].symbols[k]",json2)

                        i2 = 0
                        count_i2 = json2.SizeOfArray("property.detectedLanguages")
                        While i2 < count_i2
                            json2.I = i2
                            languageCode = json2.StringOf("property.detectedLanguages[i].languageCode")
                            i2 = i2 + 1
                        Wend
                        success = json1.ObjectOf2("paragraphs[i].words[j].symbols[k]",json2)

                        i2 = 0
                        count_i2 = json2.SizeOfArray("boundingBox.vertices")
                        While i2 < count_i2
                            json2.I = i2
                            x = json2.IntOf("boundingBox.vertices[i].x")
                            y = json2.IntOf("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

System.DebugLog("Success.")