VB.NET
VB.NET
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-textChilkat VB.NET Downloads
Dim success As Boolean = 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
Debug.WriteLine("Failed to load image file.")
Exit Sub
End If
' Create the above JSON.
Dim json As New Chilkat.JsonObject
json.UpdateBd("requests[0].image.content","base64",imageData)
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 = "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
Debug.WriteLine(http.LastErrorText)
Exit Sub
End If
Debug.WriteLine("status = " & resp.StatusCode)
' A 200 response status indicate success.
If (resp.StatusCode <> 200) Then
Debug.WriteLine(resp.BodyStr)
Debug.WriteLine("Failed.")
Exit Sub
End If
Dim sbResponseBody As New Chilkat.StringBuilder
resp.GetBodySb(sbResponseBody)
sbResponseBody.WriteFile("qa_output/textDetectResponse.json","utf-8",False)
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 Integer
Dim count_i As Integer
Dim fullTextAnnotationText As String
Dim j As Integer
Dim count_j As Integer
Dim locale As String
Dim description As String
Dim k As Integer
Dim count_k As Integer
Dim x As Integer
Dim y As Integer
Dim width As Integer
Dim height As Integer
Dim languageCode As String
Dim blockType As String
Dim i1 As Integer
Dim count_i1 As Integer
Dim j1 As Integer
Dim count_j1 As Integer
Dim k1 As Integer
Dim count_k1 As Integer
Dim text As String
Dim propertyDetectedBreakType As String
Dim i2 As Integer
Dim count_i2 As Integer
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
End While
j = j + 1
End While
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
End While
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")
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
End While
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
End While
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
End While
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
End While
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
End While
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
End While
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")
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
End While
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
End While
k1 = k1 + 1
End While
j1 = j1 + 1
End While
i1 = i1 + 1
End While
k = k + 1
End While
j = j + 1
End While
i = i + 1
End While
Debug.WriteLine("Success.")