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OCR in 1 line of code

// Nuget PM> Install Package IronOcr
using IronOcr;

var Result = new IronTesseract().Read(@"images\image.png").Text;

' Nuget PM> Install Package IronOcr
Imports IronOcr

Private Result = (New IronTesseract()).Read("images\image.png").Text

IronOCR is unique in its ability to automatically detect and read text from imperfectly scanned images and PDF documents. The `IronTesseract` Class provides the simplest API.

Try Other code samples to gain fine-grained control of your C# OCR operations.

IronOCR provides the most advanced build of Tesseract known anywhere, on any platform. With increased speed, accuracy and a native DLL and API.

Supports Tesseract 3, Tesseract 4 and Tesseract 5 for .Net Framework, Standard, Core, Xamarin and Mono.

PDF OCR Text Extraction

using IronOcr;

using (var Input = new OcrInput())
{
    // OCR entire document
    Input.AddPdf("example.pdf", "password");

    // Alternatively OCR selected page numbers
    Input.AddPdfPages("example.pdf", new[] { 1, 2, 3 }, "password");

    var Result = Ocr.Read(Input);
    Console.WriteLine(Result.Text);
}

Imports IronOcr

Using Input = New OcrInput()
	' OCR entire document
	Input.AddPdf("example.pdf", "password")

	' Alternatively OCR selected page numbers
	Input.AddPdfPages("example.pdf", { 1, 2, 3 }, "password")

	Dim Result = Ocr.Read(Input)
	Console.WriteLine(Result.Text)
End Using

Iron Tesseract can read many image formats, and also PDF documents. This feature is not possible with conventional free Tesseract engines.

OcrInput offers the option for PDF characteristics to be automatically corrected if scans are bad quality/

Developers may specify to read and entire PDF, a selection of pages or a single crop area.

OCR with Barcode & QR Reading

var Ocr = new IronTesseract();
Ocr.Configuration.ReadBarCodes = true;
using (var Input = new OcrInput(@"images\imageWithBarcode.png"))
{
    var Result = Ocr.Read(Input);
    foreach (var barcode in Result.Barcodes) {
        Console.WriteLine(barcode.Value);
    }
}

Dim Ocr = New IronTesseract()
Ocr.Configuration.ReadBarCodes = True
Using Input = New OcrInput("images\imageWithBarcode.png")
	Dim Result = Ocr.Read(Input)
	For Each barcode In Result.Barcodes
		Console.WriteLine(barcode.Value)
	Next barcode
End Using

The Iron Tesseract OcrResult object will read barcodes and QR Codes during OCR if Ocr.Configuration.ReadBarCodes = true;

This is just one of Iron Softwares valuable additions to vanilla/free Tesseract functionality.

125 International OCR Languages

//PM> Install Package IronOcr.Languages.Arabic

using IronOcr;

var Ocr = new IronTesseract();
Ocr.Language = OcrLanguage.Arabic;

using (var Input = new OcrInput(@"images\arabic.gif"))
{
    var Result = Ocr.Read(Input);
    Console.WriteLine(Result.Text);
}


///A more advanced Example

var Ocr2 = new IronTesseract();
Ocr2.UseCustomTesseractLanguageFile("custom_tesseract_files/custom.traineddata");
Ocr2.AddSecondaryLanguage(OcrLanguage.EnglishBest);

using (var Input = new OcrInput(@"images\mixed-lang.pdf"))
{
    var Result = Ocr2.Read(Input);
    Console.WriteLine(Result.Text);
}

'PM> Install Package IronOcr.Languages.Arabic

Imports IronOcr

Private Ocr = New IronTesseract()
Ocr.Language = OcrLanguage.Arabic

Using Input = New OcrInput("images\arabic.gif")
	Dim Result = Ocr.Read(Input)
	Console.WriteLine(Result.Text)
End Using


'''A more advanced Example

Dim Ocr2 = New IronTesseract()
Ocr2.UseCustomTesseractLanguageFile("custom_tesseract_files/custom.traineddata")
Ocr2.AddSecondaryLanguage(OcrLanguage.EnglishBest)

Using Input = New OcrInput("images\mixed-lang.pdf")
	Dim Result = Ocr2.Read(Input)
	Console.WriteLine(Result.Text)
End Using

IronOCR supports 125 international languages.

Other than English which is installed by default, language packs may be added to your .NET project via Nuget or as downloads from our Languages Page.

Most Languages are available in Fast, Standard (recommended) and Best quality. Best may be more accurate, but also is slower.

Fixing Low Quality Scans & Images

using IronOcr;

var Ocr = new IronTesseract();
using (var Input = new OcrInput(@"images\image.png"))
{
    Input.Deskew();
    // Input.DeNoise(); // only use if accuracy <97%
    var Result = Ocr.Read(Input);
    Console.WriteLine(Result.Text);
}

Imports IronOcr

Private Ocr = New IronTesseract()
Using Input = New OcrInput("images\image.png")
	Input.Deskew()
	' Input.DeNoise(); // only use if accuracy <97%
	Dim Result = Ocr.Read(Input)
	Console.WriteLine(Result.Text)
End Using

The IronTesseract OCR Class provides granular control to C# and .Net developers to add OCR (image and PDF to text) functionality to their application, and also to fine tune performance to their own specific use case.

By setting variables a perfect balance between speed and accuracy can be found though working with real world examples. Settings include: CleanBackgroundNoise, EnhanceContrast, EnhanceResolution, Language, Strategy, RotateAndStraighten, ColorSpace, DetectWhiteTextOnDarkBackgrounds, InputImageType.

This allows for low quality scans to be read which free Tesseract would not be able to handle.

Fast OCR Configuration

var Ocr = new IronTesseract();

// Fast Dictionary
Ocr.Language = OcrLanguage.EnglishFast;

// Latest Engine 
Ocr.Configuration.TesseractVersion = TesseractVersion.Tesseract5;

//AI OCR only without font analysis
Ocr.Configuration.EngineMode = TesseractEngineMode.LstmOnly; 

//Turn off unneeded options
Ocr.Configuration.ReadBarCodes = false;
Ocr.Configuration.RenderSearchablePdfsAndHocr = false;

// Assume text is laid out neatly in an orthagonal document
Ocr.Configuration.PageSegmentationMode = TesseractPageSegmentationMode.Auto;

using (var Input = new OcrInput(@"images\image.png"))
{
    var Result = Ocr.Read(Input);
    Console.WriteLine(Result.Text);
}

Dim Ocr = New IronTesseract()

' Fast Dictionary
Ocr.Language = OcrLanguage.EnglishFast

' Latest Engine 
Ocr.Configuration.TesseractVersion = TesseractVersion.Tesseract5

'AI OCR only without font analysis
Ocr.Configuration.EngineMode = TesseractEngineMode.LstmOnly

'Turn off unneeded options
Ocr.Configuration.ReadBarCodes = False
Ocr.Configuration.RenderSearchablePdfsAndHocr = False

' Assume text is laid out neatly in an orthagonal document
Ocr.Configuration.PageSegmentationMode = TesseractPageSegmentationMode.Auto

Using Input = New OcrInput("images\image.png")
	Dim Result = Ocr.Read(Input)
	Console.WriteLine(Result.Text)
End Using

This examples renders a 35%+ speed improvement over default setup at the cost of 0.2% accuracy.
You may also be interested in how to OCR a specific area within an image which can significantly improve speed as-well.

OCR Image Optimization Filters

using IronOcr;

var Ocr = new IronTesseract();
using (var Input = new OcrInput(@"images\image.png"))
{
    Input.WithTitle("My Document");
    Input.Binarize();
    Input.Contrast();
    Input.Deskew();
    Input.DeNoise();
    Input.Dilate();
    Input.EnhanceResolution(300);
    Input.Invert();
    Input.Rotate(90);
    Input.Scale(150); // or Input.Scale(3000, 2000);
    Input.Sharpen();
    Input.ToGrayScale();

    // you don't need all of them
    // most users only need Deskew() and occasionally DeNoise() 

    var Result = Ocr.Read(Input);
    Console.WriteLine(Result.Text);
}

Imports IronOcr

Private Ocr = New IronTesseract()
Using Input = New OcrInput("images\image.png")
	Input.WithTitle("My Document")
	Input.Binarize()
	Input.Contrast()
	Input.Deskew()
	Input.DeNoise()
	Input.Dilate()
	Input.EnhanceResolution(300)
	Input.Invert()
	Input.Rotate(90)
	Input.Scale(150) ' or Input.Scale(3000, 2000);
	Input.Sharpen()
	Input.ToGrayScale()

	' you don't need all of them
	' most users only need Deskew() and occasionally DeNoise() 

	Dim Result = Ocr.Read(Input)
	Console.WriteLine(Result.Text)
End Using

The OcrInput class provides granular control to C# and .Net developers to preprocess image input for speed and accuracy before.

This negates the common practice of using Photoshop Batch Scripts or ImageMagick to prepare images for OCR.

OcrResult Class

using IronOcr;
using System.Drawing; //for image export

// We can delve deep into OCR results as an object model of
// Pages, Barcodes, Paragraphs, Lines, Words and Characters
// This allows us to explore, export and draw OCR content using other APIs/
var Ocr = new IronTesseract();
Ocr.Configuration.EngineMode = TesseractEngineMode.TesseractAndLstm;
Ocr.Configuration.ReadBarCodes = true;
using (var Input = new OcrInput(@"example.tiff"))
{
    OcrResult Result = Ocr.Read(Input);
    foreach (var Page in Result.Pages)
    {
        // Page object
        int PageNumber = Page.PageNumber;
        string PageText = Page.Text;
        int PageWordCount = Page.WordCount;
        // null if we dont set Ocr.Configuration.ReadBarCodes = true;
        OcrResult.Barcode[] Barcodes = Page.Barcodes;
        System.Drawing.Bitmap PageImage = Page.ToBitmap(Input);
        int PageWidth = Page.Width;
        int PageHeight = Page.Height;
        foreach (var Paragraph in Page.Paragraphs)
        {
            // Pages -> Paragraphs
            int ParagraphNumber = Paragraph.ParagraphNumber;
            String ParagraphText = Paragraph.Text;
            System.Drawing.Bitmap ParagraphImage = Paragraph.ToBitmap(Input);
            int ParagraphX_location = Paragraph.X;
            int ParagraphY_location = Paragraph.Y;
            int ParagraphWidth = Paragraph.Width;
            int ParagraphHeight = Paragraph.Height;
            double ParagraphOcrAccuracy = Paragraph.Confidence;
            OcrResult.TextFlow paragrapthText_direction = Paragraph.TextDirection;
            foreach (var Line in Paragraph.Lines)
            {
                // Pages -> Paragraphs -> Lines
                int LineNumber = Line.LineNumber;
                String LineText = Line.Text;
                System.Drawing.Bitmap LineImage = Line.ToBitmap(Input); ;
                int LineX_location = Line.X;
                int LineY_location = Line.Y;
                int LineWidth = Line.Width;
                int LineHeight = Line.Height;
                double LineOcrAccuracy = Line.Confidence;
                double LineSkew = Line.BaselineAngle;
                double LineOffset = Line.BaselineOffset;
                foreach (var Word in Line.Words)
                {
                    // Pages -> Paragraphs -> Lines -> Words
                    int WordNumber = Word.WordNumber;
                    String WordText = Word.Text;
                    System.Drawing.Image WordImage = Word.ToBitmap(Input);
                    int WordX_location = Word.X;
                    int WordY_location = Word.Y;
                    int WordWidth = Word.Width;
                    int WordHeight = Word.Height;
                    double WordOcrAccuracy = Word.Confidence;
                    if (Word.Font != null)
                    {
                        // Word.Font is only set when using Tesseract Engine Modes rather than LTSM
                        String FontName = Word.Font.FontName;
                        double FontSize = Word.Font.FontSize;
                        bool IsBold = Word.Font.IsBold;
                        bool IsFixedWidth = Word.Font.IsFixedWidth;
                        bool IsItalic = Word.Font.IsItalic;
                        bool IsSerif = Word.Font.IsSerif;
                        bool IsUnderLined = Word.Font.IsUnderlined;
                        bool IsFancy = Word.Font.IsCaligraphic;
                    }
                    foreach (var Character in Word.Characters)
                    {
                        // Pages -> Paragraphs -> Lines -> Words -> Characters
                        int CharacterNumber = Character.CharacterNumber;
                        String CharacterText = Character.Text;
                        System.Drawing.Bitmap CharacterImage = Character.ToBitmap(Input);
                        int CharacterX_location = Character.X;
                        int CharacterY_location = Character.Y;
                        int CharacterWidth = Character.Width;
                        int CharacterHeight = Character.Height;
                        double CharacterOcrAccuracy = Character.Confidence;
                        // Output alternative symbols choices and their probability.
                        // Very useful for spellchecking
                        OcrResult.Choice[] Choices = Character.Choices;
                    }
                }
            }
        }
    }
}

Imports IronOcr
Imports System.Drawing 'for image export

' We can delve deep into OCR results as an object model of
' Pages, Barcodes, Paragraphs, Lines, Words and Characters
' This allows us to explore, export and draw OCR content using other APIs/
Private Ocr = New IronTesseract()
Ocr.Configuration.EngineMode = TesseractEngineMode.TesseractAndLstm
Ocr.Configuration.ReadBarCodes = True
Using Input = New OcrInput("example.tiff")
	Dim Result As OcrResult = Ocr.Read(Input)
	For Each Page In Result.Pages
		' Page object
		Dim PageNumber As Integer = Page.PageNumber
		Dim PageText As String = Page.Text
		Dim PageWordCount As Integer = Page.WordCount
		' null if we dont set Ocr.Configuration.ReadBarCodes = true;
		Dim Barcodes() As OcrResult.Barcode = Page.Barcodes
		Dim PageImage As System.Drawing.Bitmap = Page.ToBitmap(Input)
		Dim PageWidth As Integer = Page.Width
		Dim PageHeight As Integer = Page.Height
		For Each Paragraph In Page.Paragraphs
			' Pages -> Paragraphs
			Dim ParagraphNumber As Integer = Paragraph.ParagraphNumber
			Dim ParagraphText As String = Paragraph.Text
			Dim ParagraphImage As System.Drawing.Bitmap = Paragraph.ToBitmap(Input)
			Dim ParagraphX_location As Integer = Paragraph.X
			Dim ParagraphY_location As Integer = Paragraph.Y
			Dim ParagraphWidth As Integer = Paragraph.Width
			Dim ParagraphHeight As Integer = Paragraph.Height
			Dim ParagraphOcrAccuracy As Double = Paragraph.Confidence
			Dim paragrapthText_direction As OcrResult.TextFlow = Paragraph.TextDirection
			For Each Line In Paragraph.Lines
				' Pages -> Paragraphs -> Lines
				Dim LineNumber As Integer = Line.LineNumber
				Dim LineText As String = Line.Text
				Dim LineImage As System.Drawing.Bitmap = Line.ToBitmap(Input)

				Dim LineX_location As Integer = Line.X
				Dim LineY_location As Integer = Line.Y
				Dim LineWidth As Integer = Line.Width
				Dim LineHeight As Integer = Line.Height
				Dim LineOcrAccuracy As Double = Line.Confidence
				Dim LineSkew As Double = Line.BaselineAngle
				Dim LineOffset As Double = Line.BaselineOffset
				For Each Word In Line.Words
					' Pages -> Paragraphs -> Lines -> Words
					Dim WordNumber As Integer = Word.WordNumber
					Dim WordText As String = Word.Text
					Dim WordImage As System.Drawing.Image = Word.ToBitmap(Input)
					Dim WordX_location As Integer = Word.X
					Dim WordY_location As Integer = Word.Y
					Dim WordWidth As Integer = Word.Width
					Dim WordHeight As Integer = Word.Height
					Dim WordOcrAccuracy As Double = Word.Confidence
					If Word.Font IsNot Nothing Then
						' Word.Font is only set when using Tesseract Engine Modes rather than LTSM
						Dim FontName As String = Word.Font.FontName
						Dim FontSize As Double = Word.Font.FontSize
						Dim IsBold As Boolean = Word.Font.IsBold
						Dim IsFixedWidth As Boolean = Word.Font.IsFixedWidth
						Dim IsItalic As Boolean = Word.Font.IsItalic
						Dim IsSerif As Boolean = Word.Font.IsSerif
						Dim IsUnderLined As Boolean = Word.Font.IsUnderlined
						Dim IsFancy As Boolean = Word.Font.IsCaligraphic
					End If
					For Each Character In Word.Characters
						' Pages -> Paragraphs -> Lines -> Words -> Characters
						Dim CharacterNumber As Integer = Character.CharacterNumber
						Dim CharacterText As String = Character.Text
						Dim CharacterImage As System.Drawing.Bitmap = Character.ToBitmap(Input)
						Dim CharacterX_location As Integer = Character.X
						Dim CharacterY_location As Integer = Character.Y
						Dim CharacterWidth As Integer = Character.Width
						Dim CharacterHeight As Integer = Character.Height
						Dim CharacterOcrAccuracy As Double = Character.Confidence
						' Output alternative symbols choices and their probability.
						' Very useful for spellchecking
						Dim Choices() As OcrResult.Choice = Character.Choices
					Next Character
				Next Word
			Next Line
		Next Paragraph
	Next Page
End Using

IronOCR returns an advanced result object for each page it scans using Tesseract 3,4 or 5. This contains location data, images, text, statistical confidence, alternative symbol choices, font-names, font-sizes decoration and weights, rotation and position for each: 

Page
Paragraph
Line of Text
Word
Individual Character
and Barcode

Create Searchable PDFs by OCR

using IronOcr;

  var Ocr = new IronTesseract();
using (var Input = new OcrInput())
{
    Input.Add(@"images\page1.png")
    Input.Add(@"images\page2.bmp")
    Input.Add(@"images\page3.tiff")

    Input.Deskew();

    var Result = Ocr.Read(Input);
    Result.SaveAsSearchablePdf("searchable.pdf");
}

Imports IronOcr

  Private Ocr = New IronTesseract()
Using Input = New OcrInput()
	Input.Add("images\page1.png") Input.Add("images\page2.bmp") Input.Add("images\page3.tiff") Input.Deskew()

	Dim Result = Ocr.Read(Input)
	Result.SaveAsSearchablePdf("searchable.pdf")
End Using

We can use Iron's advanced Tesseract engine to convert Images to searchable PDFs. It can also make existing PDF's searchable.

This adds to SEO performance and internal search indexing within intranets and databases.

Tesseract 5 for .NET

using IronOcr;
//..
var Ocr = new IronTesseract();
Ocr.Configuration.TesseractVersion = TesseractVersion.Tesseract5;
// This is default
using (var Input = new OcrInput(@"images\image.png"))
{
    var Result = Ocr.Read(Input);
    Console.WriteLine(Result.Text);
}

Imports IronOcr
'..
Private Ocr = New IronTesseract()
Ocr.Configuration.TesseractVersion = TesseractVersion.Tesseract5
' This is default
Using Input = New OcrInput("images\image.png")
	Dim Result = Ocr.Read(Input)
	Console.WriteLine(Result.Text)
End Using

IronOCR is the only known .Net library for Tesseract 5 OCR. It is also the most advanced Tesseract 5 library known in ANY language at time of writing.

IronOCR Supports Tesseract 3, Tesseract 4 and Tesseract 5 for .Net Framework, Standard, Core, Xamarin and Mono.

Human Support Directly From Our Development Team

Whether it's product, integration or licensing queries, the Iron product development team is on hand to support all of your questions. Get in touch and start a dialog with Iron to make the most of our library in your project.

Ask a Question

Image to Text OCR
for Visual Studio

Pass IronOCR single or multi page scanned images to receive all text, barcode, & QR content in return. The OCR library provides a set of classes to add OCR functionality into Web, Desktop or Console .Net Applications. Input formats can include PDF, JPG, PNG, GIF, BMP and TIFF.

Designed for C#, VB.Net, .Net

Read the How-To Tutorials

High Accuracy
at High Speeds

The OCR (Optical Character Recognition) engine views pages formatted with multiple popular fonts, weights, italics, and underlines for accurate text reading. Cropping classes further assists OCR to perform at speed and with pinpoint accuracy. Iron’s multithreaded engine accelerates OCR speeds for multi-page documents on multi-core servers.

Get Started

Advanced Image Pre-processing for Consistent Results Every time

What really makes IronOCR special is its ability to read badly scanned documents. Its unique pre-processing library reduces background noise, rotation, distortion and skewed alignment as well as simplifying colours and enhancing resolution & contrast. Iron’s AutoOCR and Advanced OCR settings provide developers with the tools to achieve the best possible results, every time.

Learn More

Support for Languages from across the globe

Language packs available for: Arabic, Simplified Chinese, Traditional Chinese, Danish, English, Finnish, French, German, Hebrew, Italian, Japanese, Korean, Portuguese, Russian, Spanish, and Swedish. Other languages can be supported by request.

View Language Packs

Output content into your project as Structured Data

IronOCR outputs content as plain text and barcode data. An alternative structured data object model allows developers to receive all content in the format of structured Headings, Paragraphs, Lines, Words and Characters for input directly into .Net applications.

See the Object Reference