xy_to_polar ( ImageXY : ImagePolar : Row, Column, Width, Height : )

Transform an image to polar coordinates

xy_to_polar 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(x') * y' + Column
    y = sin(x') * y' + Row.


Parameters

ImageXY (input_object)
image(-array) -> object : byte
Input image in cartesian coordinates.

ImagePolar (output_object)
image(-array) -> object : byte
Result image in polar coordinates.

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

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

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

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


Example
read_image(:Image:'affe':) >
disp_image(Image:::) >
xy_to_polar(Image:PolarImage:100,100,314,200:).
disp_image(PolarImage:::) >

Alternatives

image_transform__


See also

image_transform__



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