ByteScout PDF Suite – C# – Convert Scanned PDF to Text with PDF Extractor SDK

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ByteScout PDF Suite – C# – Convert Scanned PDF to Text with PDF Extractor SDK

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How to convert scanned PDF to text with PDF extractor SDK in C# with ByteScout PDF Suite

Learn to convert scanned PDF to text with PDF extractor SDK in C#

The code displayed below will guide you to install an C# app to convert scanned PDF to text with PDF extractor SDK. ByteScout PDF Suite is the bundle that provides six different SDK libraries to work with PDF from generating rich PDF reports to extracting data from PDF documents and converting them to HTML. This bundle includes PDF (Generator) SDK, PDF Renderer SDK, PDF Extractor SDK, PDF to HTML SDK, PDF Viewer SDK and PDF Generator SDK for Javascript. It can be applied to convert scanned PDF to text with PDF extractor SDK using C#.

The SDK samples given below describe how to quickly make your application do convert scanned PDF to text with PDF extractor SDK in C# with the help of ByteScout PDF Suite. This C# sample code is all you need for your app. Just copy and paste the code, add references (if needs to) and you are all set! Enjoy writing a code with ready-to-use sample C# codes.

You can download free trial version of ByteScout PDF Suite from our website with this and other source code samples for C#.

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Program.cs

      using System.Diagnostics;
using 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'.

namespace ScannedPdfToText
{
    class Program
    {
        static void Main(string[] args)
        {
            // Create Bytescout.PDFExtractor.TextExtractor instance
            TextExtractor extractor = 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 OCRAnalyser 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 result document in default associated application (for demo purpose)
            ProcessStartInfo processStartInfo = new ProcessStartInfo("output.txt");
            processStartInfo.UseShellExecute = true;
            Process.Start(processStartInfo);
        }
    }
}