OCR and Image in WinRT (Windows Store) using LEADTOOLS WinRT Libraries
Take the following steps to start a project and to add some code that will load an image and read its barcodes in a Windows Store application using LEADTOOLS WinRT libraries.
- Start Visual Studio 2012
- Choose File --> New Project from the menu.
- In the New Project dialog box, choose "JavaScript” and "Windows Store" as the project template, and choose "Blank App" in the Templates List.
- Type the project name as "OCRImage" in the Project Name field, and then click OK. If desired, type a new location for your project or select a directory using the Browse button, and then click OK.
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In the "Solution Explorer" window, right-click on the "References" folder for the project and select "Add Reference..." from the context menu. Browse to the <LEADTOOLS_INSTALLDIR>\Bin\WinRT8_1\ folder (depending on your target platform), and select the following .WINMD files:
- Leadtools.winmd
- Leadtools.Kernel.winmd
- Leadtools.Codecs.winmd
- Leadtools.Codecs.Kernel.winmd
- Leadtools.Codecs.Bmp.winmd
- Leadtools.Codecs.Cmp.winmd
- Leadtools.Codecs.Fax.winmd
- Leadtools.Codecs.Gif.winmd
- Leadtools.Codecs.J2k.winmd
- Leadtools.Codecs.Png.winmd
- Leadtools.Codecs.Tif.winmd
- Leadtools.Dicom.winmd
- Leadtools.Converters.winmd
- Leadtools.ImageProcessing.Core
- Leadtools.ImageProcessing.Utilities
- Leadtools.ImageProcessing.Effects
- Leadtools.ImageProcessing.SpecialEffects
- Leadtools.ImageProcessing.Color
- Leadtools.Forms.Ocr
- Leadtools.Forms.DocumentWriters
Click the Add button and then click OK to add the above references.
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Add the LEADTOOLS Advantage OCR Engine runtime files to the project by doing the following:
- In the Solution Explorer window, right-click on the project and select Add-->New Folder from the context menu. Name the folder OCRRuntime and then click OK.
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Right-click the new folder and select Add-->Existing Item from the context menu. Browse to the <LEADTOOLS_INSTALLDIR>\Bin\Common\OcrAdvantageRuntime folder, and select the following files:
- Advantage.de.bin
- Advantage.en.bin
- Advantage.es.bin
- Advantage.fr.bin
- Advantage.it.bin
- Advantage.Micr.bin
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For each of the files, set the Package Action setting to Content and the Copy To Output Directory setting to Copy if newer.
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Open the default.html file and copy the below html code into the editor:
<!DOCTYPE html><html><head><meta charset="utf-8" /><title>OCRImage</title><!-- WinJS references --><link href="//Microsoft.WinJS.1.0/css/ui-dark.css" rel="stylesheet" /><script src="//Microsoft.WinJS.1.0/js/base.js"></script><script src="//Microsoft.WinJS.1.0/js/ui.js" ></script><!-- OCRImage references --><link href="/css/default.css" rel="stylesheet" /><script src="/js/default.js" ></script></head><body><input id="btnLoadAndRecognize" type="button" value="Load And Recognize Text" /><p id="statusText" ></p><textarea id="resultsTextArea" readonly="readonly" style="width: 500px; height: 500px" ></textarea></body></html> -
Change to default.js in the Solution Explorer and copy the following code into the file (overwrite all existing code):
// For an introduction to the Blank template, see the following documentation:// http://msdn.microsoft.com/en-us/library/windows/apps/hh758331.aspx(function () {"use strict";WinJS.Binding.optimizeBindingReferences = true;var app = WinJS.Application;var activation = Windows.ApplicationModel.Activation;app.onactivated = function (args) {if (args.detail.kind === activation.ActivationKind.launch) {if (args.detail.previousExecutionState !== activation.ApplicationExecutionState.terminated) {// TODO: This application has been newly launched. Initialize// your application here. LoadAndRecognize()document.getElementById("btnLoadAndRecognize").addEventListener("click" , LoadAndRecognize, false );// replace this with RasterSupport.SetLicense when you have a valid runtime license.Leadtools.RasterSupport.initialize();//Create and start the OCR enginevar engineDirectory = Windows.ApplicationModel.Package.current.installedLocation.path + "\\OCRRuntime";_ocrEngine = Leadtools.Forms.Ocr.OcrEngineManager.createEngine(Leadtools.Forms.Ocr.OcrEngineType.advantage, false);var _ocrCodecs = new Leadtools.Codecs.RasterCodecs();_ocrEngine.startup(_ocrCodecs, null , "", engineDirectory);_document = _ocrEngine.documentManager.createDocument();} else {// TODO: This application has been reactivated from suspension.// Restore application state here.}args.setPromise(WinJS.UI.processAll());}};app.oncheckpoint = function (args) {// TODO: This application is about to be suspended. Save any state// that needs to persist across suspensions here. You might use the// WinJS.Application.sessionState object, which is automatically// saved and restored across suspension. If you need to complete an// asynchronous operation before your application is suspended, call// args.setPromise().};app.start();var _ocrEngine = null ;var _document = null ;function LoadAndRecognize() {// Create a file picker objectvar openPicker = new Windows.Storage.Pickers.FileOpenPicker();openPicker.viewMode = Windows.Storage.Pickers.PickerViewMode.thumbnail;openPicker.suggestedStartLocation = Windows.Storage.Pickers.PickerLocationId.picturesLibrary;openPicker.ViewMode = Windows.Storage.Pickers.PickerViewMode.List;//Add a few supported file typesopenPicker.fileTypeFilter.append(".jpg");openPicker.fileTypeFilter.append(".jpeg");openPicker.fileTypeFilter.append(".jxr");openPicker.fileTypeFilter.append(".png");openPicker.fileTypeFilter.append(".bmp");openPicker.fileTypeFilter.append(".pcx");openPicker.fileTypeFilter.append(".tif");openPicker.fileTypeFilter.append(".tiff");openPicker.fileTypeFilter.append(".j2k");openPicker.fileTypeFilter.append(".jbg" );openPicker.fileTypeFilter.append(".gif");openPicker.fileTypeFilter.append(".jls");openPicker.fileTypeFilter.append(".jb2");openPicker.fileTypeFilter.append(".psd");openPicker.fileTypeFilter.append(".dcm");openPicker.fileTypeFilter.append(".dic");openPicker.fileTypeFilter.append(".pdf");// Open the picker for the user to pick a fileopenPicker.pickSingleFileAsync().then(function (file) {if (!file) {// The picker was dismissed with no selected filereturn;}document.getElementById('resultsTextArea').value = "";// Create a RasterCodecs object to load the filevar codecs = new Leadtools.Codecs.RasterCodecs();document.getElementById('statusText').innerText = "Loading image...";// Create a LEAD stream for the filevar leadStream = Leadtools.LeadStreamFactory.create(file);// Load itcodecs.options.load.initAlpha = true ;codecs.loadAsync(leadStream, 32, Leadtools.Codecs.CodecsLoadByteOrder.bgr, 1, 1 ).then(function (rasterImage) {_document.pages.clear();//Add the page to the OCR document_document.pages.addPage(rasterImage, null);document.getElementById('statusText').innerText = "Recognizing Text...";//Recognize the textvar results = _document.pages[0].recognizeText(null);if (results.length == 0) {document.getElementById('statusText').innerText = "No text recognized";}else {//Show the resultsdocument.getElementById('resultsTextArea').value = results;document.getElementById('statusText').innerText = "Complete";}}, function (e) {var msg = new Windows.UI.Popups.MessageDialog("Error loading image");msg.showAsync();document.getElementById('statusText').innerText = "Error loading image";});});}})(); -
Build, and Run the program to test it.
- Click the Load And Recognize Text button, and select an image.
- NOTE: If you encounter an "Invalid File Format" or "Feature Not Supported" exception, please refer to the topic Invalid File Format/Feature Not Supported.
