KeyStoneCommand Class

Summary

Performs inverse perspective transformation (keystoning) on an image.

Syntax

Objective-C

C++/CLI

Java

Python

public class KeyStoneCommand : RasterCommand

@interface LTKeyStoneCommand : LTRasterCommand

public class KeyStoneCommand 
    extends RasterCommand

public ref class KeyStoneCommand : public RasterCommand

class KeyStoneCommand(RasterCommand):

Remarks

The KeyStoneCommand is useful for correcting the perspective of images captured by portable devices. Frequently, images are distorted because they are projected onto a surface at an angle. Vertical lines become slanted, etc.
The KeyStoneCommand maps a polygon to a rectangle. The PerspectiveCommand maps a rectangle to a polygon.
If the input list of points that represents the polygon has more than 4 points, an Invalid Parameters Exception will be thrown.
This function supports 12 and 16-bit grayscale and 48 and 64-bit color images. Support for 12 and 16-bit grayscale and 48 and 64-bit color images is available in the Document/Medical Imaging toolkits.
This command supports signed/unsigned images.

Example

Java

using Leadtools; 
using Leadtools.Codecs; 
using Leadtools.ImageProcessing.Core; 
 
public void KeyStoneCommandExample() 
{ 
   RasterCodecs codecs = new RasterCodecs(); 
   codecs.ThrowExceptionsOnInvalidImages = true; 
 
   //Load an image 
   RasterImage image = codecs.Load(Path.Combine(LEAD_VARS.ImagesDir, "Master.jpg")); 
 
   LeadPoint[] PolyPoints = new LeadPoint[4]; 
 
   //The four corners of the polygon 
   PolyPoints[0] = new LeadPoint(94, 94); 
   PolyPoints[1] = new LeadPoint(306, 43); 
   PolyPoints[2] = new LeadPoint(318, 237); 
   PolyPoints[3] = new LeadPoint(98, 237); 
 
   //Prepare the command 
   KeyStoneCommand command = new KeyStoneCommand(); 
 
   command.PolygonPoints = PolyPoints; 
   //Apply  
   command.Run(image); 
 
   codecs.Save(command.TransformedImage, Path.Combine(LEAD_VARS.ImagesDir, "Result.jpg"), image.OriginalFormat, image.BitsPerPixel); 
} 
 
static class LEAD_VARS 
{ 
   public const string ImagesDir = @"C:\LEADTOOLS23\Resources\Images"; 
}

 
import java.io.File; 
import java.io.IOException; 
 
import org.junit.*; 
import org.junit.Test; 
import org.junit.runner.JUnitCore; 
import org.junit.runner.Result; 
import org.junit.runner.notification.Failure; 
import static org.junit.Assert.*; 
 
import leadtools.*; 
import leadtools.codecs.*; 
import leadtools.imageprocessing.core.*; 
 
 
public void keyStoneCommandExample() { 
    final String LEAD_VARS_IMAGES_DIR = "C:\\LEADTOOLS23\\Resources\\Images"; 
 
    RasterCodecs codecs = new RasterCodecs(); 
    codecs.setThrowExceptionsOnInvalidImages(true); 
 
    // Load an image 
    RasterImage image = codecs.load(combine(LEAD_VARS_IMAGES_DIR, "Master.jpg")); 
    LeadPoint[] polyPoints = new LeadPoint[4]; 
 
    // The four corners of the polygon 
    polyPoints[0] = new LeadPoint(94, 94); 
    polyPoints[1] = new LeadPoint(306, 43); 
    polyPoints[2] = new LeadPoint(318, 237); 
    polyPoints[3] = new LeadPoint(98, 237); 
 
    // Prepare the command 
    KeyStoneCommand command = new KeyStoneCommand(); 
    command.setPolygonPoints(polyPoints); 
 
    // Apply 
    command.run(image); 
    codecs.save(image, combine(LEAD_VARS_IMAGES_DIR, "Result.jpg"), image.getOriginalFormat(), 
            image.getBitsPerPixel()); 
 
    System.out.println("Command run and image saved to: " + combine(LEAD_VARS_IMAGES_DIR, "Result.jpg")); 
    assertTrue(new File(combine(LEAD_VARS_IMAGES_DIR, "Result.jpg")).exists()); 
 
}

Requirements

Target Platforms

Reference

KeyStoneCommand Members

Leadtools.ImageProcessing.Core Namespace

PerspectiveDeskewCommand Class

ManualPerspectiveDeskewCommand Class

UnWarpCommand Class

Download our FREE evaluation

Help Version 23.0.2024.3.3

Leadtools.ImageProcessing.Core Assembly

Introduction

Getting Started

Namespaces

Leadtools.ImageProcessing.Core Namespace

Assemblies