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ImageInversePolarTransform


Header:FIL.h
Namespace:fil

Transforms an image from polar or log-polar space to euclidean space.

Syntax

C++
C#
 
void fil::ImageInversePolarTransform
(
	const fil::Image& inImage,
	const fil::Point2D& inCenter,
	fil::PolarSpaceType::Type inInputSpaceType,
	fil::PolarInterpolationMethod::Type inInterpolation,
	fil::Image& outImage
)

Parameters

Name Type Default Description
inImage const Image& Input image
inCenter const Point2D& Center of the coordinate system in output image
inInputSpaceType PolarSpaceType::Type Method of transformation
inInterpolation PolarInterpolationMethod::Type Method of underlying interpolation
outImage Image& Output image

Description

Reverses ImagePolarTransform using the following transformation:

\[ src(x,y) = dst(\rho, \phi) \]

where

\[ \rho = m \sqrt{x^2 + y^2} , \phi = \arctan(\frac{y}{x}), \]

for linear-polar space, and

\[ \rho = k \log{\sqrt{x^2+y^2} }, \phi = \arctan(\frac{y}{x}), \]

for log-polar space, which emulates the human "foveal vision".

Parameters \(m\) and \(k\) are chosen so that entire source image could fit into output image.

Transformation does not change image dimensions.

Examples

Original image, ImagePolarTransform and ImageInversePolarTransform performed on the sample image with inCenter = (150,150) for log-polar space type.

See Also