PO - Convert image to polar representation - rays along Y.

(5/12/14)

PURPOSE

Convert rectangular image to rectangular polar coordinate representation with rays along the Y dimension.   Example.

SEE ALSO

PO R [Convert image to polar representation - rays along X]
CC P [Cross Correlation - Polar ||]
RO I [Rotational average - 2D Image output]
RO SD [Rotational average - single line output, doc file]
RI RV [Find ridges and valleys running up/down an image]

USAGE

.OPERATION: PO

.INPUT FILE: PIC001
[Enter the name of the file to be converted.]

.OUTPUT FILE: POL001
[Enter name of the file which will contain polar coordinate representation of the input image.]

.INNER AND OUTER RADIUS: 5, 50
[Only section of the image between inner and outer radius specified will be converted to polar coordinates. Thus, in the output image, first line will correspond to the inner radius specified, the last line will correspond to the outer radius. Altogether, the output image will contain (OUTER RADIUS)-(INNER RADIUS) + 1 lines.

The length of each line will be (OUTER RADIUS) * 2 * PI. The first pixel originates from the origin (center pixel) of a horizontal line halfway down the image and following rows are extracted in a clockwise direction

Each line is multiplied (weighted) by the square root of its radius. Thus, when when polar images are compared using 'CC P' operation, the result is correct.]

.FULL OR HALF CIRCLE (F/H): F
['F' - convert whole circles; 'H' - convert only half of each circle.
Option 'H' is appropriate when autocorrelation images or power spectra are converted to polar representation.]

NOTES

  1. Implemented by Paul Penczek & ArDean Leith.

SUBROUTINES

TO_POLAR

CALLER

DRIV1

© Copyright Notice /       Enquiries: spider@wadsworth.org