polar_trans

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

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) `->` object : byte / int2 / uint2
Input image in cartesian coordinates.

`ImagePolar` (output_object)	(multichannel-)image(-array) `->` object : byte / int2 / uint2
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
Typical 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
Typical 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
Typical 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
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)

Parallelization Information

polar_trans_image is reentrant and automatically parallelized (on tuple level, channel level).

Alternatives

affine_trans_image

Module

Foundation