B4X Requires Chilkat v11.0.0+
B4X
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 B4X 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 ChilkatBinData
imageData.Initialize
' This image file contains some text...
success = imageData.LoadFile("qa_data/jpg/text.jpg")
If success <> True Then
Log("Failed to load image file.")
Return
End If
' Create the above JSON.
Dim json As ChilkatJsonObject
json.Initialize
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 ChilkatHttp
http.Initialize("http")
http.SessionLogFilename = "c:/aaworkarea/sessionLog.txt"
Dim sb As ChilkatStringBuilder
sb.Initialize
Dim url As String = "https://vision.googleapis.com/v1/images:annotate?key=YOUR_API_KEY"
Dim resp As ChilkatHttpResponse
resp.Initialize
success = http.HttpJson("POST", url, json, "application/json", resp)
If success = False Then
Log(http.LastErrorText)
Return
End If
Log("status = " & resp.StatusCode)
' A 200 response status indicate success.
If resp.StatusCode <> 200 Then
Log(resp.BodyStr)
Log("Failed.")
Return
End If
Dim sbResponseBody As ChilkatStringBuilder
sbResponseBody.Initialize
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 Int
Dim count_i As Int
Dim fullTextAnnotationText As String
Dim j As Int
Dim count_j As Int
Dim locale As String
Dim description As String
Dim k As Int
Dim count_k As Int
Dim x As Int
Dim y As Int
Dim width As Int
Dim height As Int
Dim languageCode As String
Dim blockType As String
Dim i1 As Int
Dim count_i1 As Int
Dim j1 As Int
Dim count_j1 As Int
Dim k1 As Int
Dim count_k1 As Int
Dim text As String
Dim propertyDetectedBreakType As String
Dim i2 As Int
Dim count_i2 As Int
Dim json1 As ChilkatJsonObject
json1.Initialize
Dim json2 As ChilkatJsonObject
json2.Initialize
i = 0
count_i = json.SizeOfArray("responses")
Do While i < count_i
json.I = i
fullTextAnnotationText = json.StringOf("responses[i].fullTextAnnotation.text")
j = 0
count_j = json.SizeOfArray("responses[i].textAnnotations")
Do 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")
Do 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
Loop
j = j + 1
Loop
j = 0
count_j = json.SizeOfArray("responses[i].fullTextAnnotation.pages")
Do 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")
Do While k < count_k
json.K = k
languageCode = json.StringOf("responses[i].fullTextAnnotation.pages[j].property.detectedLanguages[k].languageCode")
k = k + 1
Loop
k = 0
count_k = json.SizeOfArray("responses[i].fullTextAnnotation.pages[j].blocks")
Do 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")
Do While i1 < count_i1
json1.I = i1
languageCode = json1.StringOf("property.detectedLanguages[i].languageCode")
i1 = i1 + 1
Loop
json.ObjectOf2("responses[i].fullTextAnnotation.pages[j].blocks[k]", json1)
i1 = 0
count_i1 = json1.SizeOfArray("boundingBox.vertices")
Do While i1 < count_i1
json1.I = i1
x = json1.IntOf("boundingBox.vertices[i].x")
y = json1.IntOf("boundingBox.vertices[i].y")
i1 = i1 + 1
Loop
json.ObjectOf2("responses[i].fullTextAnnotation.pages[j].blocks[k]", json1)
i1 = 0
count_i1 = json1.SizeOfArray("paragraphs")
Do While i1 < count_i1
json1.I = i1
j1 = 0
count_j1 = json1.SizeOfArray("paragraphs[i].property.detectedLanguages")
Do While j1 < count_j1
json1.J = j1
languageCode = json1.StringOf("paragraphs[i].property.detectedLanguages[j].languageCode")
j1 = j1 + 1
Loop
j1 = 0
count_j1 = json1.SizeOfArray("paragraphs[i].boundingBox.vertices")
Do 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
Loop
j1 = 0
count_j1 = json1.SizeOfArray("paragraphs[i].words")
Do While j1 < count_j1
json1.J = j1
k1 = 0
count_k1 = json1.SizeOfArray("paragraphs[i].words[j].property.detectedLanguages")
Do While k1 < count_k1
json1.K = k1
languageCode = json1.StringOf("paragraphs[i].words[j].property.detectedLanguages[k].languageCode")
k1 = k1 + 1
Loop
k1 = 0
count_k1 = json1.SizeOfArray("paragraphs[i].words[j].boundingBox.vertices")
Do 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
Loop
k1 = 0
count_k1 = json1.SizeOfArray("paragraphs[i].words[j].symbols")
Do 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")
Do While i2 < count_i2
json2.I = i2
languageCode = json2.StringOf("property.detectedLanguages[i].languageCode")
i2 = i2 + 1
Loop
json1.ObjectOf2("paragraphs[i].words[j].symbols[k]", json2)
i2 = 0
count_i2 = json2.SizeOfArray("boundingBox.vertices")
Do While i2 < count_i2
json2.I = i2
x = json2.IntOf("boundingBox.vertices[i].x")
y = json2.IntOf("boundingBox.vertices[i].y")
i2 = i2 + 1
Loop
k1 = k1 + 1
Loop
j1 = j1 + 1
Loop
i1 = i1 + 1
Loop
k = k + 1
Loop
j = j + 1
Loop
i = i + 1
Loop
Log("Success.")