IsInverted Method

Summary

Gets a value that indicate whether this IOcrPage is inverted.

Syntax

Objective-C

C++/CLI

Java

Python

public bool IsInverted()

- (BOOL)isInverted:(NSError **)error

public boolean isInverted()

bool IsInverted();

def IsInverted(self):

Return Value

true if this IOcrPage is inverted; otherwise, false.

Remarks

You can use this method to detect if the page is inverted (has white text over black background). This method will work on the processing version of the image inside the page (OcrPageType.Processing).

Use AutoPreprocess with OcrAutoPreprocessPageCommand.Invert to automatically invert the page image prior to calling Recognize. This could enhance the quality of the image before starting its recognition.

If the image is inverted, IsInverted will return true, if you call AutoPreprocess on the page, all subsequent calls to IsInverted will return false since the image is no inverted. Hence, you must use IsInverted before calling AutoPreprocess.

Use GetPreprocessValues to obtain the accumulative pre-processing values applied to this IOcrPage.

Example

using Leadtools; 
using Leadtools.Codecs; 
using Leadtools.Ocr; 
using Leadtools.Forms.Common; 
using Leadtools.Document.Writer; 
using Leadtools.WinForms; 
using Leadtools.Drawing; 
using Leadtools.ImageProcessing; 
using Leadtools.ImageProcessing.Color; 
 
public void AutoPreprocessExample() 
{ 
   string tifFileName = Path.Combine(LEAD_VARS.ImagesDir, "Clean.tif"); 
   string pdfFileName = Path.Combine(LEAD_VARS.ImagesDir, "Clean.pdf"); 
 
   // Create an instance of the engine 
   using (IOcrEngine ocrEngine = OcrEngineManager.CreateEngine(OcrEngineType.LEAD)) 
   { 
      // Start the engine using default parameters 
      ocrEngine.Startup(null, null, null, LEAD_VARS.OcrLEADRuntimeDir); 
 
      // Create an OCR document 
      using (IOcrDocument ocrDocument = ocrEngine.DocumentManager.CreateDocument()) 
      { 
         // Add this image to the document 
         IOcrPage ocrPage = ocrDocument.Pages.AddPage(tifFileName, null); 
 
         // Auto-preprocess it 
         ocrPage.AutoPreprocess(OcrAutoPreprocessPageCommand.Deskew, null); 
         ocrPage.AutoPreprocess(OcrAutoPreprocessPageCommand.Invert, null); 
         ocrPage.AutoPreprocess(OcrAutoPreprocessPageCommand.Rotate, null); 
 
         // Recognize it and save it as PDF 
         ocrPage.Recognize(null); 
         ocrDocument.Save(pdfFileName, DocumentFormat.Pdf, null); 
      } 
 
      // Shutdown the engine 
      // Note: calling Dispose will also automatically shutdown the engine if it has been started 
      ocrEngine.Shutdown(); 
   } 
} 
 
static class LEAD_VARS 
{ 
   public const string ImagesDir = @"C:\LEADTOOLS23\Resources\Images"; 
   public const string OcrLEADRuntimeDir = @"C:\LEADTOOLS23\Bin\Common\OcrLEADRuntime"; 
}

Requirements

Target Platforms

Reference

IOcrPage Interface

IOcrPage Members

AutoPreprocess Method

GetRotateAngle Method

GetDeskewAngle Method

Recognize Method

OcrAutoPreprocessPageCommand Enumeration

IOcrPageCollection Interface

IOcrZoneCollection Interface

OcrZone Structure

Programming with the LEADTOOLS .NET OCR

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Help Version 23.0.2024.3.3