lvblse(3)

LIBRARY ROUTINE
lvblse - Perform band-limited surface extrapolation (adaptive apodization)

LIBRARY CALL
#include "vinclude.h"
int
lvblse(image,mask,psf,count)
struct xvimage *image,*mask,*psf;
int count;

INPUT

image
    Pointer to input image.

mask
    Pointer to valid data mask image the the above input image.

psf Pointer to pointspread function image.

count
    Iteration count (int)

OUTPUT

image
    pointer to which the resultant image is attached. The original image is overwritten and the original data area is freed.

MODIFICATIONS

12-Feb-90 Scott Wilson - Patched around the disappearance of the original FFT calls.

DESCRIPTION
lvblse

performs band-limited surface extrapolation or adaptive apodization. Applications are in spectral estimation, image reconstruction and image restoration. The method used is the classical Gerchberg-Saxton method except that the relaxation constraint is allowed to change bandwidth over the course of the iterations. In this implementation, the relaxation bandwidth is a linear combination of a unity bandpass with the passband of a user specified extrapolation pointspread function. The ratio of these two passbands is determined by the percentage of the iterations that have been completed: intially, the bandwidth is unity, but decreses to exactly that specified by the user at the last iteration.

SEE ALSO
vblse(1), intro(3), vipl(3), verror(3), vutils(3)

RESTRICTIONS
Works only on FLOAT images.

AUTHOR
Scott Wilson

COPYRIGHT
Copyright 1991, University of New Mexico. All rights reserved.