Class IronTesseract

IronTesseract is a comprehensive managed class for performing Tesseract OCR in .Net applications.

IronTesseract natively supports Tesseract 3, 4 and 5 engines, and will automatically install all required binaries and language packs (tessdata) files.

Inheritance

System.Object

IronTesseract

Inherited Members

System.Object.Equals(System.Object)

System.Object.Equals(System.Object, System.Object)

System.Object.GetHashCode()

System.Object.GetType()

System.Object.MemberwiseClone()

System.Object.ToString()

System.Object.ReferenceEquals(System.Object, System.Object)

Namespace: IronOcr

Assembly: IronOcr.dll

Syntax

public class IronTesseract

Constructors

IronTesseract()

Public constructor. Creates a default instance of IronTesseract

Declaration

public IronTesseract()

IronTesseract(TesseractConfiguration)

Public constructor. Creates an instance of IronTesseract with a customized TesseractConfiguration.

This allows advanced developers to fine tune Tesseract behavior.

Declaration

public IronTesseract(TesseractConfiguration Configuration)

Parameters

Type	Name	Description
TesseractConfiguration	Configuration

Fields

Configuration

An instance of TesseractConfiguration which allows fine-grained control of the underlying Tesseract OCR Engine.

Options include: Tesseract Engine 4 or 5. Language file detail level. Page Segmentation Mode and access to the entire API of tesseract settings variables.

Declaration

public TesseractConfiguration Configuration

Field Value

Type	Description
TesseractConfiguration

Properties

AzureFunctionWebRootPath

set Azure Function Web Root Path by using ExecutionContext class EX. ExecutionContext executionContext; var engine = new IronTesseract(); engine.AzureFunctionWebRootPath = executionContext.FunctionAppDirectory;

Declaration

public string AzureFunctionWebRootPath { get; set; }

Property Value

Type	Description
System.String

Language

The Natural Language of the documents Which IronTesseract will read.

Default is English. Additional languages can be installed easily using Nuget https://www.nuget.org/packages?q=IronOcr.Languages or downloaded from https://ironsoftware.com/csharp/ocr/languages/

We may use multiple languages packs simultaneously with the UseMultipleLanguages method.

We can use custom Tesseract .tessdata language packs with the UseCustomTesseractLanguageFile(String) method.

Declaration

public OcrLanguage Language { get; set; }

Property Value

Type	Description
OcrLanguage

See Also

OcrLanguage

MultiThreaded

Allows IronTesseract to read documents using multiple threads on multiple CPU cores. A significant performance improvement over traditional Tesseract.

Declaration

public bool MultiThreaded { get; set; }

Property Value

Type	Description
System.Boolean

Methods

AddSecondaryLanguage(OcrLanguage)

IronTesseract will use multiple tesseract language files simultaneously. MultilingualOCR.

Any number of secondary languages may be added. Speed and performance may be affected.

Declaration

public void AddSecondaryLanguage(OcrLanguage SecondaryLanguage)

Parameters

Type	Name	Description
OcrLanguage	SecondaryLanguage	An additional OcrLanguage

AddSecondaryLanguage(String)

IronTesseract will use multiple tesseract language files simultaneously. MultilingualOCR using a custom .traineddata tesseract 3,4 or 5 language file.

Any number of secondary languages may be added. Speed and performance may be affected.

Declaration

public void AddSecondaryLanguage(string CustomLanguagePath)

Parameters

Type	Name	Description
System.String	CustomLanguagePath	File path to a .traineddata tesseract language pack.

ClearSecondaryLanguages()

Removes all languages add by AddSecondaryLanguage(OcrLanguage) or AddSecondaryLanguage(String)

Declaration

public void ClearSecondaryLanguages()

Read(OcrInput)

Reads text from an OcrInput object and returns an OcrResult object.

OcrInput is the preferred input type because it allows for OCR of multi-paged documents, and allows images to be enhanced before OCR to obtain faster, more accurate results.

There are also other overloads of this method that allow for Images and PDFs to be read directly as File paths and Bitmaps.

Declaration

public OcrResult Read(OcrInput Input)

Parameters

Type	Name	Description
OcrInput	Input	An OcrInput document which can contain one or more images and PDFs

Returns

Type	Description
OcrResult	A OcrResult object containing text, and detailed, structured information about the extracted text content.

Read(Image)

Reads text from a System.Drawing.Image Image file and returns an OcrResult object.

Declaration

public OcrResult Read(Image Image)

Parameters

Type	Name	Description
System.Drawing.Image	Image	A System.Drawing.Image or Bitmap

Returns

Type	Description
OcrResult	A OcrResult object containing text, and detailed, structured information about the extracted text content.

Read(Image, Rectangle)

Reads text from a region of a System.Drawing.Image Image file and returns an OcrResult object.

Declaration

public OcrResult Read(Image Image, Rectangle ContentArea)

Parameters

Type	Name	Description
System.Drawing.Image	Image	A System.Drawing.Image or Bitmap
System.Drawing.Rectangle	ContentArea	Specifies a region within the image to extract text from as a System.Drawing.Rectangle with X, Y Width and Height in pixels. Setting a ContentArea can improve OCR speed.

Returns

Type	Description
OcrResult	A OcrResult object containing text, and detailed, structured information about the extracted text content.

Read(String)

Reads text from an Image file and returns an OcrResult object.

Declaration

public OcrResult Read(string ImagePath)

Parameters

Type	Name	Description
System.String	ImagePath	Path to an image file.

Returns

Type	Description
OcrResult	A OcrResult object containing text, and detailed, structured information about the extracted text content.

Read(String, Rectangle)

Reads text from a region of an Image file and returns an OcrResult object.

Declaration

public OcrResult Read(string ImagePath, Rectangle ContentArea)

Parameters

Type	Name	Description
System.String	ImagePath	Path to an image file.
System.Drawing.Rectangle	ContentArea	Specifies a region within the image to extract text from as a System.Drawing.Rectangle with X, Y Width and Height in pixels. Setting a ContentArea can improve OCR speed.

Returns

Type	Description
OcrResult	A OcrResult object containing text, and detailed, structured information about the extracted text content.

ReadAsync(OcrInput)

Reads text from an OcrInput object and returns an OcrResult object.

OcrInput is the preferred input type because it allows for OCR of multi-paged documents, and allows images to be enhanced before OCR to obtain faster, more accurate results.

There are also other overloads of this method that allow for Images and PDFs to be read directly as File paths and Bitmaps.

Declaration

public Task<OcrResult> ReadAsync(OcrInput Input)

Parameters

Type	Name	Description
OcrInput	Input	An OcrInput document which can contain one or more images and PDFs

Returns

Type	Description
System.Threading.Tasks.Task<OcrResult>	A task that represents the asynchronous read operation. The value of the System.Threading.Tasks.Task`1.Result property contains an OcrResult object containing text, and detailed, structured information about the extracted text content.

ReadAsync(Image, Nullable<Rectangle>)

Reads text from an System.Drawing.Image object and returns an OcrResult object.

Declaration

public Task<OcrResult> ReadAsync(Image Image, Rectangle? ContentArea = null)

Parameters

Type	Name	Description
System.Drawing.Image	Image	An System.Drawing.Image object
System.Nullable<System.Drawing.Rectangle>	ContentArea	Specifies a region within the image to extract text from as a System.Drawing.Rectangle with X, Y Width and Height in pixels. Setting a ContentArea can improve OCR speed.

Returns

Type	Description
System.Threading.Tasks.Task<OcrResult>	A task that represents the asynchronous read operation. The value of the System.Threading.Tasks.Task`1.Result property contains an OcrResult object containing text, and detailed, structured information about the extracted text content.

ReadAsync(String, Nullable<Rectangle>)

Reads text from an Image file and returns an OcrResult object.

Declaration

public Task<OcrResult> ReadAsync(string ImagePath, Rectangle? ContentArea = null)

Parameters

Type	Name	Description
System.String	ImagePath	Path to an image file.
System.Nullable<System.Drawing.Rectangle>	ContentArea	Specifies a region within the image to extract text from as a System.Drawing.Rectangle with X, Y Width and Height in pixels. Setting a ContentArea can improve OCR speed.

Returns

Type	Description
System.Threading.Tasks.Task<OcrResult>	A task that represents the asynchronous read operation. The value of the System.Threading.Tasks.Task`1.Result property contains an OcrResult object containing text, and detailed, structured information about the extracted text content.

UseCustomTesseractLanguageFile(String)

IronTesseract will use a tesseract .traineddata language file as its only OCR language.

https://github.com/tesseract-ocr/tessdata

Declaration

public void UseCustomTesseractLanguageFile(string TrainedDataPath)

Parameters

Type	Name	Description
System.String	TrainedDataPath	File path to a .traineddata file. These can be downloaded from https://github.com/tesseract-ocr/tessdata or generated using Tesseract command line.

Events

OcrProgress

An Event which can be used to track OCR progress and inform users of OCR performance and progress.

Progress is reported via the OcrProgresEventsArgs class

Declaration

public event EventHandler<OcrProgresEventsArgs> OcrProgress

Event Type

Type	Description
System.EventHandler<OcrProgresEventsArgs>

Examples

myIronTesseract.OcrProgress += (object o, IronOcr.Events.OcrProgresEventsArgs e) =>
                   {
                      Console.WriteLine(e.ProgressPercent + "%   " + e.Duration.TotalSeconds+"s"  );
                   }

See Also

OcrProgresEventsArgs

Inherited members

System.Object.Equals(System.Object)

System.Object.Equals(System.Object, System.Object)

System.Object.GetHashCode()

System.Object.GetType()

System.Object.MemberwiseClone()

System.Object.ToString()

System.Object.ReferenceEquals(System.Object, System.Object)