Herror ::polar_trans_image (
    Hobject ImageXY,
    Hobject *ImagePolar,
    const HTuple &Row,
    const HTuple &Column,
    const HTuple &Width,
    const HTuple &Height
)
HImage HImage::PolarTransImage (
    const HTuple &Row,
    const HTuple &Column,
    const HTuple &Width,
    const HTuple &Height
) const
HImageArray HImageArray::PolarTransImage (
    const HTuple &Row,
    const HTuple &Column,
    const HTuple &Width,
    const HTuple &Height
) const

Transform an image to polar coordinates

::polar_trans_image transforms an image in cartesian coordinates to an image in polar coordinates. The size of the resulting image is selected with Width and Height. Width determines the angular resolution, while Height determines the resolution of the radius. Row and Column determine the center of the polar coordinate system in the original image ImageXY. This point is mapped to the upper row of ImagePolar.

A point (x',y') in the result image corresponds to the point (x,y) in the original image in the following manner:

    x = cos(2*pi*(x'/result_width)) * y' + Column 

y = sin(2*pi*(x'/result_width)) * y' + Row.


Parameters

ImageXY (input_object)
(multichannel-)image(-array) -> Hobject: HImage(Array) ( byte / int2 )
Input image in cartesian coordinates.

ImagePolar (output_object)
(multichannel-)image(-array) -> Hobject * : HImage(Array) ( byte / int2 )
Result image in polar coordinates.

Row (input_control)
point.y -> HTuple.long
Row coordinate of the center of the coordinate system.
Default value: 100
Suggested values: 0, 10, 100, 200
Typical range of values: 0 <= Row <= 512
Minimum increment: 1
Recommended increment: 1

Column (input_control)
point.x -> HTuple.long
Column coordinate of the center of the coordinate system.
Default value: 100
Suggested values: 0, 10, 100, 200
Typical range of values: 0 <= Column <= 512
Minimum increment: 1
Recommended increment: 1

Width (input_control)
extent.x -> HTuple.long
Width of the result image.
Default value: 314
Suggested values: 100, 200, 157, 314, 512
Typical range of values: 2 <= Width <= 512
Minimum increment: 1
Recommended increment: 10

Height (input_control)
extent.y -> HTuple.long
Height of the result image.
Default value: 200
Suggested values: 100, 128, 256, 512
Typical range of values: 2 <= Height <= 512
Minimum increment: 1
Recommended increment: 10


Example
read_image(&Image,"affe");
disp_image(Image,WindowHandle);
polar_trans_image(Image,&PolarImage,100,100,314,200);
disp_image(PolarImage,WindowHandle);

Alternatives

::affine_trans_image


Module

Image filters



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