Xbase++
Xbase++
Amazon Rekognition - Detect Text in an Image
See more Amazon Rekognition Examples
Detects text in the input image and converts it into machine-readable text. This example passes theimage as base64-encoded image bytes.Chilkat Xbase++ Downloads
LOCAL nSuccess
LOCAL oRest
LOCAL oAuthAws
LOCAL nBTls
LOCAL nPort
LOCAL nBAutoReconnect
LOCAL oBdJpg
LOCAL oSbJpg
LOCAL oJson
LOCAL oSbRequestBody
LOCAL oSbResponseBody
LOCAL nRespStatusCode
LOCAL oJResp
LOCAL cConfidence
LOCAL cDetectedText
LOCAL cGeometryBoundingBoxHeight
LOCAL cGeometryBoundingBoxLeft
LOCAL cGeometryBoundingBoxTop
LOCAL cGeometryBoundingBoxWidth
LOCAL nId
LOCAL cV_Type
LOCAL nParentId
LOCAL j
LOCAL nCount_j
LOCAL X
LOCAL Y
LOCAL cTextModelVersion
LOCAL i
LOCAL nCount_i
nSuccess := 0
oRest := CreateObject("Chilkat.Rest")
oAuthAws := CreateObject("Chilkat.AuthAws")
oAuthAws:AccessKey := "AWS_ACCESS_KEY"
oAuthAws:SecretKey := "AWS_SECRET_KEY"
// Don't forget to change the region to your particular region. (Also make the same change in the call to Connect below.)
oAuthAws:Region := "us-west-2"
oAuthAws:ServiceName := "rekognition"
// SetAuthAws causes Chilkat to automatically add the following headers: Authorization, X-Amz-Date
oRest:SetAuthAws(oAuthAws)
// URL: https://rekognition.us-west-2.amazonaws.com/
nBTls := 1
nPort := 443
nBAutoReconnect := 1
// Don't forget to change the region domain (us-west-2.amazonaws.com) to your particular region.
nSuccess := oRest:Connect("rekognition.us-west-2.amazonaws.com", nPort, nBTls, nBAutoReconnect)
IF (nSuccess != 1)
? "ConnectFailReason: " + Str(oRest:ConnectFailReason)
? oRest:LastErrorText
oRest:destroy()
oAuthAws:destroy()
RETURN
ENDIF
// Note: The above code does not need to be repeatedly called for each REST request.
// The rest object can be setup once, and then many requests can be sent. Chilkat will automatically
// reconnect within a FullRequest* method as needed. It is only the very first connection that is explicitly
// made via the Connect method.
// Load the JPG to be passed as base64 in the JSON.
oBdJpg := CreateObject("Chilkat.BinData")
nSuccess := oBdJpg:LoadFile("qa_data/jpg/monday_keep_smiling.jpg")
IF (nSuccess != 1)
? "Failed to load the input JPG file."
oRest:destroy()
oAuthAws:destroy()
oBdJpg:destroy()
RETURN
ENDIF
// We wish to send the following JSON in the body of our HTTP request:
// {
// "Image": {
// "Bytes": "base64_image_bytes"
// }
// }
// Here is the image we used for testing:
// (image:https://example-code.com/images/monday_keep_smiling.jpg/endImage)
// Convert binary image bytes to base64.
// Note: We are explicitly keeping the data inside Chilkat to avoid having to pass large strings
// as arguments to function calls. This is important for some programming languages.
oSbJpg := CreateObject("Chilkat.StringBuilder")
oBdJpg:GetEncodedSb("base64", oSbJpg)
oJson := CreateObject("Chilkat.JsonObject")
oJson:UpdateSb("Image.Bytes", oSbJpg)
oRest:AddHeader("Content-Type", "application/x-amz-json-1.1")
oRest:AddHeader("X-Amz-Target", "RekognitionService.DetectText")
oSbRequestBody := CreateObject("Chilkat.StringBuilder")
oJson:EmitSb(oSbRequestBody)
oSbResponseBody := CreateObject("Chilkat.StringBuilder")
nSuccess := oRest:FullRequestSb("POST", "/", oSbRequestBody, oSbResponseBody)
IF (nSuccess != 1)
? oRest:LastErrorText
oRest:destroy()
oAuthAws:destroy()
oBdJpg:destroy()
oSbJpg:destroy()
oJson:destroy()
oSbRequestBody:destroy()
oSbResponseBody:destroy()
RETURN
ENDIF
nRespStatusCode := oRest:ResponseStatusCode
? "response status code = " + Str(nRespStatusCode)
IF (nRespStatusCode >= 400)
? "Response Status Code = " + Str(nRespStatusCode)
? "Response Header:"
? oRest:ResponseHeader
? "Response Body:"
? oSbResponseBody:GetAsString()
oRest:destroy()
oAuthAws:destroy()
oBdJpg:destroy()
oSbJpg:destroy()
oJson:destroy()
oSbRequestBody:destroy()
oSbResponseBody:destroy()
RETURN
ENDIF
oJResp := CreateObject("Chilkat.JsonObject")
oJResp:LoadSb(oSbResponseBody)
oJResp:EmitCompact := 0
? oJResp:Emit()
// Sample JSON response:
// (Sample code for parsing the JSON response is shown below)
// {
// "TextDetections": [
// {
// "Confidence": 95.99308776855469,
// "DetectedText": "( MONDAY IT'S",
// "Geometry": {
// "BoundingBox": {
// "Height": 0.6399821043014526,
// "Left": 0.219133198261261,
// "Top": 0.08677978068590164,
// "Width": 0.7433173656463623
// },
// "Polygon": [
// {
// "X": 0.219133198261261,
// "Y": 0.3588336706161499
// },
// {
// "X": 0.8984103798866272,
// "Y": 0.08677978068590164
// },
// {
// "X": 0.9624505639076233,
// "Y": 0.4547080099582672
// },
// {
// "X": 0.2831733524799347,
// "Y": 0.7267619371414185
// }
// ]
// },
// "Id": 0,
// "Type": "LINE"
// },
// {
// "Confidence": 99.70352172851562,
// "DetectedText": "but keep",
// "Geometry": {
// "BoundingBox": {
// "Height": 0.09703556448221207,
// "Left": 0.6335319876670837,
// "Top": 0.5153074264526367,
// "Width": 0.21070890128612518
// },
// "Polygon": [
// {
// "X": 0.6355597376823425,
// "Y": 0.5153074264526367
// },
// {
// "X": 0.8442409038543701,
// "Y": 0.5266726613044739
// },
// {
// "X": 0.8422132134437561,
// "Y": 0.6123430132865906
// },
// {
// "X": 0.6335319876670837,
// "Y": 0.6009777784347534
// }
// ]
// },
// "Id": 1,
// "Type": "LINE"
// },
// {
// "Confidence": 99.92333984375,
// "DetectedText": "Smiling",
// "Geometry": {
// "BoundingBox": {
// "Height": 0.31578224897384644,
// "Left": 0.5070608258247375,
// "Top": 0.6086956262588501,
// "Width": 0.4795433282852173
// },
// "Polygon": [
// {
// "X": 0.5070608258247375,
// "Y": 0.6298336386680603
// },
// {
// "X": 0.9808917045593262,
// "Y": 0.6086956262588501
// },
// {
// "X": 0.9866041541099548,
// "Y": 0.9033399224281311
// },
// {
// "X": 0.5127732157707214,
// "Y": 0.9244779348373413
// }
// ]
// },
// "Id": 2,
// "Type": "LINE"
// },
// {
// "Confidence": 99.77294158935547,
// "DetectedText": "IT'S",
// "Geometry": {
// "BoundingBox": {
// "Height": 0.09903381764888763,
// "Left": 0.668789803981781,
// "Top": 0.17874395847320557,
// "Width": 0.1449044644832611
// },
// "Polygon": [
// {
// "X": 0.668789803981781,
// "Y": 0.17874395847320557
// },
// {
// "X": 0.8136942386627197,
// "Y": 0.17874395847320557
// },
// {
// "X": 0.8136942386627197,
// "Y": 0.2777777910232544
// },
// {
// "X": 0.668789803981781,
// "Y": 0.2777777910232544
// }
// ]
// },
// "Id": 5,
// "ParentId": 0,
// "Type": "WORD"
// },
// {
// "Confidence": 98.44307708740234,
// "DetectedText": "MONDAY",
// "Geometry": {
// "BoundingBox": {
// "Height": 0.11112251877784729,
// "Left": 0.5541401505470276,
// "Top": 0.3526569902896881,
// "Width": 0.39013487100601196
// },
// "Polygon": [
// {
// "X": 0.5541401505470276,
// "Y": 0.3526569902896881
// },
// {
// "X": 0.9442675113677979,
// "Y": 0.3502415418624878
// },
// {
// "X": 0.9458598494529724,
// "Y": 0.4613526463508606
// },
// {
// "X": 0.5541401505470276,
// "Y": 0.4637681245803833
// }
// ]
// },
// "Id": 4,
// "ParentId": 0,
// "Type": "WORD"
// },
// {
// "Confidence": 99.61898803710938,
// "DetectedText": "but",
// "Geometry": {
// "BoundingBox": {
// "Height": 0.06521739065647125,
// "Left": 0.6353503465652466,
// "Top": 0.5241546034812927,
// "Width": 0.0843949019908905
// },
// "Polygon": [
// {
// "X": 0.6353503465652466,
// "Y": 0.5241546034812927
// },
// {
// "X": 0.7197452187538147,
// "Y": 0.5241546034812927
// },
// {
// "X": 0.7197452187538147,
// "Y": 0.5893719792366028
// },
// {
// "X": 0.6353503465652466,
// "Y": 0.5893719792366028
// }
// ]
// },
// "Id": 6,
// "ParentId": 1,
// "Type": "WORD"
// },
// {
// "Confidence": 99.78804779052734,
// "DetectedText": "keep",
// "Geometry": {
// "BoundingBox": {
// "Height": 0.07971014827489853,
// "Left": 0.7308917045593262,
// "Top": 0.5265700221061707,
// "Width": 0.1114649698138237
// },
// "Polygon": [
// {
// "X": 0.7308917045593262,
// "Y": 0.5265700221061707
// },
// {
// "X": 0.8423566818237305,
// "Y": 0.5265700221061707
// },
// {
// "X": 0.8423566818237305,
// "Y": 0.6062802076339722
// },
// {
// "X": 0.7308917045593262,
// "Y": 0.6062802076339722
// }
// ]
// },
// "Id": 7,
// "ParentId": 1,
// "Type": "WORD"
// },
// {
// "Confidence": 89.76324462890625,
// "DetectedText": "(",
// "Geometry": {
// "BoundingBox": {
// "Height": 0.16401274502277374,
// "Left": 0.27229300141334534,
// "Top": 0.6642512083053589,
// "Width": 0.2850286066532135
// },
// "Polygon": [
// {
// "X": 0.27229300141334534,
// "Y": 0.6642512083053589
// },
// {
// "X": 0.2707006335258484,
// "Y": 0.37922704219818115
// },
// {
// "X": 0.43471336364746094,
// "Y": 0.37922704219818115
// },
// {
// "X": 0.4363057315349579,
// "Y": 0.6642512083053589
// }
// ]
// },
// "Id": 3,
// "ParentId": 0,
// "Type": "WORD"
// },
// {
// "Confidence": 99.92333984375,
// "DetectedText": "Smiling",
// "Geometry": {
// "BoundingBox": {
// "Height": 0.294724702835083,
// "Left": 0.5079618096351624,
// "Top": 0.6304348111152649,
// "Width": 0.4734293222427368
// },
// "Polygon": [
// {
// "X": 0.5079618096351624,
// "Y": 0.6304348111152649
// },
// {
// "X": 0.9808917045593262,
// "Y": 0.6086956262588501
// },
// {
// "X": 0.9856687784194946,
// "Y": 0.9033816456794739
// },
// {
// "X": 0.512738823890686,
// "Y": 0.9227052927017212
// }
// ]
// },
// "Id": 8,
// "ParentId": 2,
// "Type": "WORD"
// }
// ],
// "TextModelVersion": "3.0"
// }
//
//
// Sample code for parsing the JSON response...
// Use the following online tool to generate parsing code from sample JSON:
// Generate Parsing Code from JSON
cTextModelVersion := oJResp:StringOf("TextModelVersion")
i := 0
nCount_i := oJResp:SizeOfArray("TextDetections")
DO WHILE i < nCount_i
oJResp:I := i
cConfidence := oJResp:StringOf("TextDetections[i].Confidence")
cDetectedText := oJResp:StringOf("TextDetections[i].DetectedText")
cGeometryBoundingBoxHeight := oJResp:StringOf("TextDetections[i].Geometry.BoundingBox.Height")
cGeometryBoundingBoxLeft := oJResp:StringOf("TextDetections[i].Geometry.BoundingBox.Left")
cGeometryBoundingBoxTop := oJResp:StringOf("TextDetections[i].Geometry.BoundingBox.Top")
cGeometryBoundingBoxWidth := oJResp:StringOf("TextDetections[i].Geometry.BoundingBox.Width")
nId := oJResp:IntOf("TextDetections[i].Id")
cV_Type := oJResp:StringOf("TextDetections[i].Type")
nParentId := oJResp:IntOf("TextDetections[i].ParentId")
j := 0
nCount_j := oJResp:SizeOfArray("TextDetections[i].Geometry.Polygon")
DO WHILE j < nCount_j
oJResp:J := j
X := oJResp:StringOf("TextDetections[i].Geometry.Polygon[j].X")
Y := oJResp:StringOf("TextDetections[i].Geometry.Polygon[j].Y")
j := j + 1
ENDDO
i := i + 1
ENDDO
oRest:destroy()
oAuthAws:destroy()
oBdJpg:destroy()
oSbJpg:destroy()
oJson:destroy()
oSbRequestBody:destroy()
oSbResponseBody:destroy()
oJResp:destroy()