ByteScout PDF Extractor SDK – VB.NET – OCR (Optical Character Recognition) and PDF

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ByteScout PDF Extractor SDK – VB.NET – OCR (Optical Character Recognition) and PDF

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ByteScout-PDF-Extractor-SDK-VB-NET-OCR-(Optical-Character-Recognition)-and-PDF.pdf

OCR (optical character recognition) and PDF in VB.NET and ByteScout PDF Extractor SDK

Tutorial: how to do OCR (optical character recognition) and PDF in VB.NET

The coding tutorials are designed to help you test the features without need to write your own code. ByteScout PDF Extractor SDK was made to help with OCR (optical character recognition) and PDF in VB.NET. ByteScout PDF Extractor SDK is the SDK that helps developers to extract data from unstructured documents, pdf, images, scanned and electronic forms. Includes AI functions like automatic table detection, automatic table extraction and restructuring, text recognition and text restoration from pdf and scanned documents. Includes PDF to CSV, PDF to XML, PDF to JSON, PDF to searchable PDF functions as well as methods for low level data extraction.

VB.NET, code samples for VB.NET, developers help to speed up the application development and writing a code when using ByteScout PDF Extractor SDK. VB.NET sample code is all you need: copy and paste the code to your VB.NET application’s code editor, add a reference to ByteScout PDF Extractor SDK (if you haven’t added yet) and you are ready to go! Enjoy writing a code with ready-to-use sample VB.NET codes to implement OCR (optical character recognition) and PDF using ByteScout PDF Extractor SDK.

ByteScout PDF Extractor SDK is available as free trial. You may get it from our website along with all other source code samples for VB.NET applications.

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Program.vb

      Imports Bytescout.PDFExtractor

' This example demonstrates the use of Optical Character Recognition (OCR) to extract text 
' from scanned PDF documents and raster images.

' To make OCR work you should add the following references to your project:
' "Bytescout.PDFExtractor.dll", "Bytescout.PDFExtractor.OCRExtension.dll".

Class Program

    Friend Shared Sub Main(args As String())

        ' Create Bytescout.PDFExtractor.TextExtractor instance
        Dim extractor As New TextExtractor()
        extractor.RegistrationName = "demo"
        extractor.RegistrationKey = "demo"

        ' Load sample PDF document
        extractor.LoadDocumentFromFile("sample_ocr.pdf")

        ' Enable Optical Character Recognition (OCR)
        ' in .Auto mode (SDK automatically checks if needs to use OCR or not)
        extractor.OCRMode = OCRMode.Auto

        ' Set the location of OCR language data files
        extractor.OCRLanguageDataFolder = "c:\Program Files\Bytescout PDF Extractor SDK\ocrdata"
        
        ' Set OCR language
        extractor.OCRLanguage = "eng"  ' "eng" for english, "deu" for German, "fra" for French, "spa" for Spanish etc - according to files in "ocrdata" folder
        ' Find more language files at https://github.com/bytescout/ocrdata
        
        ' Set PDF document rendering resolution
        extractor.OCRResolution = 300
        
        
        ' You can also apply various preprocessing filters
        ' to improve the recognition on low-quality scans.
        
        ' Automatically deskew skewed scans
        'extractor.OCRImagePreprocessingFilters.AddDeskew()

        ' Remove vertical or horizontal lines (sometimes helps to avoid OCR engine's page segmentation errors)
        'extractor.OCRImagePreprocessingFilters.AddVerticalLinesRemover()
        'extractor.OCRImagePreprocessingFilters.AddHorizontalLinesRemover()
        
        ' Repair broken letters
        'extractor.OCRImagePreprocessingFilters.AddDilate()

        ' Remove noise
        'extractor.OCRImagePreprocessingFilters.AddMedian()
        
        ' Apply Gamma Correction
        'extractor.OCRImagePreprocessingFilters.AddGammaCorrection()
        
        ' Add Contrast
		' extractor.OCRImagePreprocessingFilters.AddContrast(20)


        ' (!) You can use new OCRAnalyzer class to find an optimal set of image preprocessing 
		' filters for your specific document.
		' See "OCR Analyser" example.


        ' Save extracted text to file
        extractor.SaveTextToFile("output.txt")

        ' Cleanup
		extractor.Dispose()

        ' Open output file in default associated application
        System.Diagnostics.Process.Start("output.txt")

    End Sub
    
End Class