ChangeCompression Method

Summary

Compresses or decompresses this RasterImage.

Syntax

C++

Java

public void ChangeCompression( 
   RasterCompression compression 
)

Public Sub ChangeCompression( _ 
   ByVal compression As RasterCompression _ 
)

public void changeCompression(RasterCompression compression)

public: 
void ChangeCompression(  
   RasterCompression compression 
)

Parameters

compression
Indicates the type of compression to use on the image.

Remarks

This method is available only in (Document/Medical only) toolkits.

For more information, refer to Speeding Up 1-Bit Documents.

This method does not support signed images.

Example

This example toggles image compression.

using Leadtools; 
using Leadtools.Codecs; 
using Leadtools.ImageProcessing; 
using Leadtools.ImageProcessing.Core; 
using Leadtools.ImageProcessing.Color; 
using Leadtools.Dicom; 
using Leadtools.Drawing; 
using Leadtools.Controls; 
using Leadtools.Svg; 
 
 
public void ChangeCompressionTest() 
{ 
	// This method toggles image compression. 
	RasterCodecs codecs = new RasterCodecs(); 
 
	// Load the image compressed 
	codecs.Options.Load.Compressed = true; 
	RasterImage image = codecs.Load(Path.Combine(LEAD_VARS.ImagesDir, "OCR1.TIF")); 
	String str = "BEFORE - ImageSize: " + image.DataSize + " bytes, Type: " + (image.IsCompressed ? "Compressed" : "UnCompressed"); 
	Console.WriteLine(str, "ChangeCompression"); 
	image.ChangeCompression((image.IsCompressed == true) ? RasterCompression.None : RasterCompression.Rle); 
	str = "AFTER - ImageSize: " + image.DataSize + " bytes, Type: " + (image.IsCompressed ? "Compressed" : "UnCompressed"); 
	Console.WriteLine(str, "ChangeCompression"); 
 
	// Load the image super-compressed 
	codecs.Options.Load.SuperCompressed = true; 
	image = codecs.Load(Path.Combine(LEAD_VARS.ImagesDir, "IMAGE1.CMP")); 
	str = "BEFORE - ImageSize: " + image.DataSize + " bytes, Type: " + (image.IsSuperCompressed ? "Compressed" : "UnCompressed"); 
	Console.WriteLine(str, "ChangeCompression"); 
	image.ChangeCompression((image.IsSuperCompressed == true) ? RasterCompression.None : RasterCompression.Super); 
	str = "AFTER - ImageSize: " + image.DataSize + " bytes, Type: " + (image.IsSuperCompressed ? "Compressed" : "UnCompressed"); 
	Console.WriteLine(str, "ChangeCompression"); 
 
	image.Dispose(); 
	codecs.Dispose(); 
} 
 
static class LEAD_VARS 
{ 
   public const string ImagesDir = @"C:\LEADTOOLS21\Resources\Images"; 
}

Imports Leadtools 
Imports Leadtools.Codecs 
Imports Leadtools.ImageProcessing 
Imports Leadtools.ImageProcessing.Core 
Imports Leadtools.ImageProcessing.Color 
Imports Leadtools.Controls 
Imports Leadtools.Dicom 
Imports Leadtools.Drawing 
Imports Leadtools.Svg 
 
Public Sub ChangeCompressionTest() 
   ' This method toggles image compression. 
   Dim codecs As RasterCodecs = New RasterCodecs() 
 
   ' Load the image compressed 
   codecs.Options.Load.Compressed = True 
   Dim image As RasterImage = codecs.Load(Path.Combine(LEAD_VARS.ImagesDir, "OCR1.TIF")) 
   Dim str As String 
   If image.IsCompressed Then 
      str = "BEFORE - ImageSize: " & image.DataSize & " bytes, Type: " & ("Compressed") 
   Else 
      str = "BEFORE - ImageSize: " & image.DataSize & " bytes, Type: " & ("UnCompressed") 
   End If 
   Console.WriteLine(str, "ChangeCompression") 
   If (image.IsCompressed = True) Then 
      image.ChangeCompression(RasterCompression.None) 
   Else 
      image.ChangeCompression(RasterCompression.Rle) 
   End If 
   If image.IsCompressed Then 
      str = "AFTER - ImageSize: " & image.DataSize & " bytes, Type: " & ("Compressed") 
   Else 
      str = "AFTER - ImageSize: " & image.DataSize & " bytes, Type: " & ("UnCompressed") 
   End If 
   Console.WriteLine(str, "ChangeCompression") 
 
   ' Load the image super-compressed 
   codecs.Options.Load.SuperCompressed = True 
   image = codecs.Load(Path.Combine(LEAD_VARS.ImagesDir, "IMAGE1.CMP")) 
   If image.IsSuperCompressed Then 
      str = "BEFORE - ImageSize: " & image.DataSize & " bytes, Type: " & ("Compressed") 
   Else 
      str = "BEFORE - ImageSize: " & image.DataSize & " bytes, Type: " & ("UnCompressed") 
   End If 
   Console.WriteLine(str, "ChangeCompression") 
   If (image.IsSuperCompressed = True) Then 
      image.ChangeCompression(RasterCompression.None) 
   Else 
      image.ChangeCompression(RasterCompression.Super) 
   End If 
   If image.IsSuperCompressed Then 
      str = "AFTER - ImageSize: " & image.DataSize & " bytes, Type: " & ("Compressed") 
   Else 
      str = "AFTER - ImageSize: " & image.DataSize & " bytes, Type: " & ("UnCompressed") 
   End If 
   Console.WriteLine(str, "ChangeCompression") 
 
   image.Dispose() 
   codecs.Dispose() 
End Sub 
 
Public NotInheritable Class LEAD_VARS 
   Public Const ImagesDir As String = "C:\LEADTOOLS21\Resources\Images" 
End Class

Requirements

Target Platforms

Reference

RasterImage Class

RasterImage Members

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Help Version 21.0.2021.7.2

Leadtools Assembly

Introduction

Getting Started

Namespaces

Leadtools Namespace

Leadtools.ImageProcessing Namespace

Assemblies