DetectLanguages Method

C#
Visual Basic
WinRT C#
Java
Objective-C
WinRT JavaScript
C++

string[] DetectLanguages( 
   string[] languages
)

'Declaration

Function DetectLanguages( _
   ByVal languages() As String _
) As String()

'Usage

Dim instance As IOcrPage
Dim languages() As String
Dim value() As String
 
value = instance.DetectLanguages(languages)

string[] DetectLanguages( 
   string[] languages
)

- (NSArray<NSNumber *> *)detectLanguages:(NSArray<NSNumber *> *)languages error:(NSError **)error

function Leadtools.Forms.Ocr.IOcrPage.DetectLanguages( 
   languages 
)

array<String^>^ DetectLanguages( 
   array<String^>^ languages
)

Parameters

languages

An array of String objects that contains the names of the languages to check for. The language values used throughout the LEADTOOLS OCR toolkit are string values based on RFC 4646 (Windows Vista and later). The name could be an ISO 639 two-letter lowercase culture code associated with a language or a combination of ISO 630 and ISO 3166 two-letter uppercase subculture codes associated with a country or region.

It's suggested to use few (fewer than 5) languages only. The recognition engine will use all those language dictionaries to recognize the words in the document.

Return Value

An array of String objects that contains the names of the detected page language(s).

DetectLanguages is only supported in the LEADTOOLS Professional and Advantage OCR engines.

The page may contain a single language only, but it can be any Latin-alphabet or Asian language.

Note: Automatic detection of Greek and Cyrillic is not proposed.

If the language can not be determined, the language of the previous page will be used.

To improve the detection accuracy, set an array with possible languages to be used, then pass it through the languages parameter.

Automatic language detection is performed as a relatively fast initial processing step before character recognition. Therefore, the accuracy will dependent on the image quality and many other conditions.

Use the GetSupportedLanguages to obtain a list of the languages supported by the IOcrEngine.

Use the IsLanguageSupported to check if a given language is supported by the IOcrEngine.

This example will detect images with English, French, and German languages.

C#
Visual Basic
WinRT C#
WinRT JavaScript
Silverlight C#
Silverlight VB

Copy Code

Imports Leadtools
Imports Leadtools.Codecs
Imports Leadtools.Forms.Ocr
Imports Leadtools.Forms.DocumentWriters

Public Sub DetectLanguagesExample()
   Dim tifFileName As String = Path.Combine(LEAD_VARS.ImagesDir, "OCR1.tif")
   ' Create an instance of the engine
   Using ocrEngine As IOcrEngine = OcrEngineManager.CreateEngine(OcrEngineType.Professional, False)
      ' Start the engine using default parameters
      ocrEngine.Startup(Nothing, Nothing, Nothing, Nothing)

      ' Create an OCR document
      Using ocrDocument As IOcrDocument = ocrEngine.DocumentManager.CreateDocument()
         ' Add this image to the document
         Dim ocrPage As IOcrPage = ocrDocument.Pages.AddPage(tifFileName, Nothing)

         ' Auto detect page language.
         Dim languages As String() = {"en", "fr", "de"}
         Dim pageLanguages As String() = ocrPage.DetectLanguages(languages)

         If pageLanguages IsNot Nothing AndAlso pageLanguages.Length > 0 Then
            Console.WriteLine("Page language(s):{0}", Environment.NewLine)
            For Each lang As String In pageLanguages
               ' Get the friendly name of this language using the .NET CultureInfo class
               Dim ci As New CultureInfo(lang)
               Console.WriteLine("{0}{1}", ci.EnglishName, Environment.NewLine)
            Next
         End If
      End Using

      ' Shutdown the engine
      ' Note: calling Dispose will also automatically shutdown the engine if it has been started
      ocrEngine.Shutdown()
   End Using
End Sub

using Leadtools;
using Leadtools.Codecs;
using Leadtools.Forms.Ocr;
using Leadtools.Forms;
using Leadtools.Forms.DocumentWriters;
using Leadtools.WinForms;
using Leadtools.Drawing;
using Leadtools.ImageProcessing;
using Leadtools.ImageProcessing.Color;

public void DetectLanguagesExample()
{
   string tifFileName = Path.Combine(LEAD_VARS.ImagesDir, "OCR1.tif");
   // Create an instance of the engine
   using (IOcrEngine ocrEngine = OcrEngineManager.CreateEngine(OcrEngineType.Professional, false))
   {
      // Start the engine using default parameters
      ocrEngine.Startup(null, null, null, null);

      // Create an OCR document
      using (IOcrDocument ocrDocument = ocrEngine.DocumentManager.CreateDocument())
      {
         // Add this image to the document
         IOcrPage ocrPage = ocrDocument.Pages.AddPage(tifFileName, null);

         // Auto detect page language.
         string[] languages = { "en", "fr", "de" };
         string[] pageLanguages = ocrPage.DetectLanguages(languages);

         if (pageLanguages != null && pageLanguages.Length > 0)
         {
            Console.WriteLine("Page language(s):{0}", Environment.NewLine);
            foreach (string lang in pageLanguages)
            {
               // Get the friendly name of this language using the .NET CultureInfo class
               CultureInfo ci = new CultureInfo(lang);
               Console.WriteLine("{0}{1}", ci.EnglishName, Environment.NewLine);
            }
         }
      }

      // Shutdown the engine
      // Note: calling Dispose will also automatically shutdown the engine if it has been started
      ocrEngine.Shutdown();
   }
}

Target Platforms

Reference

IOcrPage Interface
IOcrPage Members
IOcrLanguageManager Interface
GetSupportedLanguages Method
IsLanguageSupported Method
IOcrEngine.Startup
IOcrEngine.IsStarted
IOcrEngine.Shutdown
OcrEngineManager Class
OcrEngineType Enumeration
Programming with the LEADTOOLS .NET OCR
Working with OCR Languages
OCR Languages and Spell Checking