GetRegion Method

Summary

Gets the RasterRegion object that describes this RasterImage current region.

Syntax

Objective-C

C++/CLI

Java

Python

public RasterRegion GetRegion( 
   RasterRegionXForm xform 
)

- (nullable LTRasterRegion *)getRegion:(nullable LTRasterRegionXForm *)xform error:(NSError **)error

public RasterRegion getRegion( 
   RasterRegionXForm xform 
); 
public void setRegion( 
   RasterRegionXForm rasterRegionXForm, 
   RasterRegion rasterRegion, 
   RasterRegionCombineMode rasterRegionCombineMode 
);

public: 
RasterRegion^ GetRegion(  
   RasterRegionXForm^ xform 
)

def GetRegion(self,xform):

Parameters

xform
RasterRegionXForm object that LEADTOOLS uses to translate between display coordinates and image coordinates. If you specify null for this parameter, the scalar fields default to 1, the offsets default to 0, and the view perspective defaults to the image view perspective.

Return Value

An RasterRegion object that describes this RasterImage current region.

Remarks

To set or updated the RasterRegion object that describes the current image region, use SetRegion.

If the image does not have a region, this method will return an empty RasterRegion object.

The RasterRegion class provides a platform independent representation of a region of interest in an image that can be used in any platform supported by LEADTOOLS such as GDI, GDI+, and WPF. The RasterRegion class contains extensive methods and properties to manipulate the region data and save/load it to a byte array.

To convert a LEADTOOLS RasterRegion object to/from a device dependent region, you can use the following helper classes:

Leadtools.Drawing.RasterRegionConverter to convert to/from a System.Drawing (GDI+) System.Drawing.Region or Windows HRGN objects.
Leadtools.Windows.Media.RasterRegionConverter to convert to/from a WPF System.Windows.Media.Geometry object.

The RasterRegion class implements the IDisposable interface, so you must call Dispose on any region objects you create after using it.

For more information, refer to Creating a Region.

For more information, refer to Saving A Region.

For more information, refer to Working with the Existing Region.

Example

using Leadtools; 
using Leadtools.Codecs; 
using Leadtools.ImageProcessing; 
 
 
public void RasterRegionExample() 
{ 
   string srcFileName = Path.Combine(LEAD_VARS.ImagesDir, "Image1.cmp"); 
   string destFileName1 = Path.Combine(LEAD_VARS.ImagesDir, "Image1_WithRegion1.bmp"); 
   string destFileName2 = Path.Combine(LEAD_VARS.ImagesDir, "Image1_WithRegion2.bmp"); 
 
   using (RasterCodecs codecs = new RasterCodecs()) 
   { 
      // Load the source image 
      using (RasterImage image = codecs.Load(srcFileName, 0, CodecsLoadByteOrder.BgrOrGray, 1, 1)) 
      { 
         // Create a new rectangular RasterRegion 
         using (RasterRegion region = new RasterRegion(new LeadRect(20, 30, 100, 200))) 
         { 
            // Show this region properties 
            Console.WriteLine("IsEmpty: {0}\nBounds: {1}", region.IsEmpty, region.GetBounds()); 
 
            // Set it into the image 
            image.SetRegion(null, region, RasterRegionCombineMode.Set); 
 
            // Fill the image with a color and save it to disk to show the region 
            FillCommand cmd = new FillCommand(RasterColor.FromKnownColor(RasterKnownColor.Yellow)); 
            cmd.Run(image); 
 
            codecs.Save(image, destFileName1, RasterImageFormat.Bmp, 24); 
 
            // Clear this region 
            region.MakeEmpty(); 
 
            // Show its properties 
            Console.WriteLine("IsEmpty: {0}\nBounds: {1}", region.IsEmpty, region.GetBounds()); 
 
            // Set it into the image and fill again with red, notice 
            // that this will fill the whole image since 
            // the region is now empty 
            image.SetRegion(null, region, RasterRegionCombineMode.Set); 
 
            cmd = new FillCommand(RasterColor.FromKnownColor(RasterKnownColor.Red)); 
            cmd.Run(image); 
 
            codecs.Save(image, destFileName2, RasterImageFormat.Bmp, 24); 
         } 
      } 
   } 
} 
 
static class LEAD_VARS 
{ 
   public const string ImagesDir = @"C:\LEADTOOLS22\Resources\Images"; 
}

Requirements

Target Platforms

Reference

RasterImage Class

RasterImage Members

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Help Version 22.0.2023.5.16

Leadtools Assembly

Introduction

Getting Started

Namespaces

Leadtools Namespace

Leadtools.ImageProcessing Namespace

Assemblies