CC P - Cross Correlation - Polar ||

PURPOSE

Computes the 1D cross-correlation function of two pictures by using the Fourier transform relationship. The dimensions of the two pictures must be the same; however, the dimensions need not be powers of two (see 'FT' for restrictions).

SEE ALSO

CC N	[Cross Correlation - Normalized ||]
CN	[Convolution ||]
CN N	[Convolution - Normalized ||]
AC	[Auto Correlation ||]
AC N	[Auto Correlation - Normalized ||]
CC C	[Cross Correlation Coefficient]
FT	[Fourier Transform ||]
PO	[Convert an image to polar coordinates representation.]

USAGE

.OPERATION: CC P X11,X12

[The optional output parameters X11,X12 specify register positions for the rotation angle and the value of the angular correlation peak found in this operation. This output is relevant only when input images were polar coordinates representations of rectangular images (operation 'PO').]

.INPUT FILE: PIC001
[Enter the name of the first picture.]

.REFER FILE: REF001
[Enter the name of the second picture, which is used as the reference.]

.OUTPUT FILE: CCF001
[Enter name of the file which will contain 1D cross-correlation coefficients.]

.(F)ULL OR (H)ALF CIRCLE: F
[Specify whether input polar coordinates images were created using option F or H in operation 'PO'.]

NOTES

1. For rectangular images, this operation calculates 1D crosscorrelation functions between respective lines of input images and all of them are added to create an 1D output. This makes it possible to calculate cross-correlation function between images converted to polar coordinates using 'PO' operation.

2. The cross-correlation data are not scaled.

3. The origin of the CCF is at (INT(NSAM/2) + 1).

4. Operation 'CC P' works properly for 1D images (images consiting of one line only).

SUBROUTINES

POLAR_CC, FFTMCF, FMRS_1

CALLER

CORR1