Important Update
Writing of the code to OCR (optical character recognition) in PDF with PDF extractor SDK in ASP.NET C# can be done by developers of any level using ByteScout Premium Suite. OCR (optical character recognition) in PDF with PDF extractor SDK in ASP.NET C# can be applied with ByteScout Premium Suite. ByteScout Premium Suite is the bundle that includes twelve SDK products from ByteScout including tools and components for PDF, barcodes, spreadsheets, screen video recording.
ASP.NET C# code snippet like this for ByteScout Premium Suite works best when you need to quickly implement OCR (optical character recognition) in PDF with PDF extractor SDK in your ASP.NET C# application. Follow the steps-by-step instructions from the scratch to work and copy and paste code for ASP.NET C# into your editor. These ASP.NET C# sample examples can be used in one or many applications.
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<%@ Page Language="C#" AutoEventWireup="true" CodeBehind="Default.aspx.cs" Inherits="OpticalCharacterRecognition._Default" %>
<!DOCTYPE html PUBLIC "-//W3C//DTD XHTML 1.0 Transitional//EN" "http://www.w3.org/TR/xhtml1/DTD/xhtml1-transitional.dtd">
<html xmlns="http://www.w3.org/1999/xhtml" >
<head runat="server">
<title>Untitled Page</title>
</head>
<body>
<form id="form1" runat="server">
<div>
</div>
</form>
</body>
</html>
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using System;
using Bytescout.PDFExtractor;
// Before running the example, copy missing *.traineddata files from "Redistributable" folder to "ocrdata" project folder.
// or download from https://github.com/bytescout/ocrdata
// Make sure "Copy to Output Directory" property of each added language file is set to "Copy always".
namespace OpticalCharacterRecognition
{
/*
IF YOU SEE TEMPORARY FOLDER ACCESS ERRORS:
Temporary folder access is required for web application when you use ByteScout SDK in it.
If you are getting errors related to the access to temporary folder like "Access to the path 'C:\Windows\TEMP\... is denied" then you need to add permission for this temporary folder to make ByteScout SDK working on that machine and IIS configuration because ByteScout SDK requires access to temp folder to cache some of its data for more efficient work.
SOLUTION:
If your IIS Application Pool has "Load User Profile" option enabled the IIS provides access to user's temp folder. Check user's temporary folder
If you are running Web Application under an impersonated account or IIS_IUSRS group, IIS may redirect all requests into separate temp folder like "c:\temp\".
In this case
- check the User or User Group your web application is running under
- then add permissions for this User or User Group to read and write into that temp folder (c:\temp or c:\windows\temp\ folder)
- restart your web application and try again
*/
public partial class _Default : System.Web.UI.Page
{
protected void Page_Load(object sender, EventArgs e)
{
String inputFile = Server.MapPath(@".\bin\sample_ocr.pdf");
// Location of language files
String ocrLanguageDataFolder = Server.MapPath(@".\bin\ocrdata");
// Create Bytescout.PDFExtractor.TextExtractor instance
using (TextExtractor extractor = new TextExtractor())
{
extractor.RegistrationName = "demo";
extractor.RegistrationKey = "demo";
// 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 = ocrLanguageDataFolder;
// 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
// 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.
// Load PDF document
extractor.LoadDocumentFromFile(inputFile);
// Write extracted text to output stream
Response.Clear();
Response.ContentType = "text/html";
Response.Write("<pre>");
// Write extracted text to output stream
Response.Write(extractor.GetText());
Response.Write("</pre>");
Response.End();
}
}
}
}
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//------------------------------------------------------------------------------
// <auto-generated>
// This code was generated by a tool.
// Runtime Version:2.0.50727.4952
//
// Changes to this file may cause incorrect behavior and will be lost if
// the code is regenerated.
// </auto-generated>
//------------------------------------------------------------------------------
namespace ExtractAllText {
/// <summary>
/// _Default class.
/// </summary>
/// <remarks>
/// Auto-generated class.
/// </remarks>
public partial class _Default {
/// <summary>
/// form1 control.
/// </summary>
/// <remarks>
/// Auto-generated field.
/// To modify move field declaration from designer file to code-behind file.
/// </remarks>
protected global::System.Web.UI.HtmlControls.HtmlForm form1;
}
}
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<?xml version="1.0"?>
<configuration>
<appSettings/>
<connectionStrings/>
<system.web>
<!--
Set compilation debug="true" to insert debugging
symbols into the compiled page. Because this
affects performance, set this value to true only
during development.
-->
<compilation debug="true" />
<!--
The <authentication> section enables configuration
of the security authentication mode used by
ASP.NET to identify an incoming user.
-->
<authentication mode="Windows" />
<!--
The <customErrors> section enables configuration
of what to do if/when an unhandled error occurs
during the execution of a request. Specifically,
it enables developers to configure html error pages
to be displayed in place of a error stack trace.
<customErrors mode="RemoteOnly" defaultRedirect="GenericErrorPage.htm">
<error statusCode="403" redirect="NoAccess.htm" />
<error statusCode="404" redirect="FileNotFound.htm" />
</customErrors>
-->
</system.web>
</configuration>
60 Day Free Trial or Visit ByteScout Premium Suite Home Page
Explore ByteScout Premium Suite Documentation
Explore Samples
Sign Up for ByteScout Premium Suite Online Training
Get Your API Key
Explore Web API Docs
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60 Day Free Trial or Visit ByteScout Premium Suite Home Page
Explore ByteScout Premium Suite Documentation
Explore Samples
Sign Up for ByteScout Premium Suite Online Training
Get Your API Key
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