ByteScout PDF Extractor SDK – VB.NET – OCR With Fast Dataset

Home
/
Articles
/
ByteScout PDF Extractor SDK – VB.NET – OCR With Fast Dataset

printable version:
ByteScout-PDF-Extractor-SDK-VB-NET-OCR-With-Fast-Dataset.pdf

OCR with fast dataset in VB.NET with ByteScout PDF Extractor SDK

Write code in VB.NET to make OCR with fast dataset with this How-To tutorial

We’ve created and updating regularly our sample code library so you may quickly learn OCR with fast dataset and the step-by-step process in VB.NET. ByteScout PDF Extractor SDK helps with OCR with fast dataset in VB.NET. ByteScout PDF Extractor SDK is the SDK is designed to help developers with pdf tables and pdf data extraction from unstructured documents like pdf, tiff, scans, images, scanned and electronic forms. The library is powered by OCR, computer vision and AI to provide unique functionality like table detection, automatic table structure extraction, data restoration, data restructuring and reconstruction. Supports PDF, TIFF, PNG, JPG images as input and can output CSV, XML, JSON formatted data. Includes full set of utilities like pdf splitter, pdf merger, searchable pdf maker and other utilities.

This rich sample source code in VB.NET for ByteScout PDF Extractor SDK includes the number of functions and options you should do calling the API to implement OCR with fast dataset. To do OCR with fast dataset in your VB.NET project or application you may simply copy & paste the code and then run your app! Enhanced documentation and tutorials are available along with installed ByteScout PDF Extractor SDK if you’d like to dive deeper into the topic and the details of the API.

Trial version can be downloaded from our website. Source code samples for VB.NET and documentation are included.

On-demand (REST Web API) version:
Web API (on-demand version)

On-premise offline SDK for Windows:
60 Day Free Trial (on-premise)

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_fast"
        
        ' 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/tree/master/ocrdata_fast
        
        ' 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