Module imagingbook.common

Package imagingbook.common.geometry.mappings.linear

Class Scaling2D

java.lang.Object

imagingbook.common.geometry.mappings.linear.LinearMapping2D

imagingbook.common.geometry.mappings.linear.ProjectiveMapping2D

imagingbook.common.geometry.mappings.linear.AffineMapping2D

imagingbook.common.geometry.mappings.linear.Scaling2D

All Implemented Interfaces:

Inversion, Jacobian, Mapping2D, Cloneable

public class Scaling2D
extends AffineMapping2D

This class represents a 2D scaling transformation (as a special case of affine transformation). See Secs. 21.1.3 and 21.3.1 of [1] for details.

[1] W. Burger, M.J. Burge, Digital Image Processing – An Algorithmic Introduction, 3rd ed, Springer (2022).

Field Summary

Fields inherited from class imagingbook.common.geometry.mappings.linear.LinearMapping2D

a00, a01, a02, a10, a11, a12, a20, a21, a22

Constructor Summary

Constructors

Constructor	Description
Scaling2D(double s)	Constructor.
Scaling2D(double sx, double sy)	Constructor.
Scaling2D(Scaling2D sc)

Method Summary

Modifier and Type	Method	Description
Scaling2D	duplicate()	Returns a copy of this mapping.
Scaling2D	getInverse()	Calculates and returns the inverse mapping.

Methods inherited from class imagingbook.common.geometry.mappings.linear.AffineMapping2D

applyTo, concat, fromPoints, fromPoints, getJacobian, isAffine

Methods inherited from class imagingbook.common.geometry.mappings.linear.ProjectiveMapping2D

concat, main

Methods inherited from class imagingbook.common.geometry.mappings.linear.LinearMapping2D

concat, concatenate, getTransformationMatrix, normalize, toString

Methods inherited from class java.lang.Object

clone, equals, finalize, getClass, hashCode, notify, notifyAll, wait, wait, wait

Methods inherited from interface imagingbook.common.geometry.mappings.Mapping2D

applyTo

Constructor Details

Scaling2D

public Scaling2D(Scaling2D sc)

Scaling2D

public Scaling2D(double sx,
 double sy)

Constructor. Creates a mapping that scales along the x- and y-axis by the associated factors.

Parameters:

sx - the scale factor in x-direction

sy - the scale factor in y-direction

Scaling2D

public Scaling2D(double s)

Constructor. Creates a uniform scaling in x and y.

Parameters:

s - the common scale factor

Method Details

getInverse

public Scaling2D getInverse()

Calculates and returns the inverse mapping. Note that the inverse A' of a projective transformation matrix A is again a linear transformation but its a'2' element is generally not 1. Scaling A' to A'' = A' / a22' yields a projective transformation that reverses A. While A * A' = I, the result of A * A'' is a scaled identity matrix. Note that inverting an affine transformation always yields another affine transformation.

Specified by:

getInverse in interface Inversion

Overrides:

getInverse in class AffineMapping2D

Returns:

a new scaling transformation

duplicate

public Scaling2D duplicate()

Returns a copy of this mapping.

Overrides:

duplicate in class AffineMapping2D

Returns:

a new scaling transformation