CLEAN

Name

clean

Purpose

Remove a PSF from an image via the ``clean'' algorithm.

Description

Calling Sequence

clean,image,psf,xloc,yloc,maxdist,iters,new_image,resid $
DISPLAY=display,VERBOSE=verbose

Inputs

image - Original source image to be cleaned.
psf - PSF image at same sampling resolution as image.
xloc - X location of "object"
yloc - Y location of "object"
maxdist - Maximum distance from xyloc to look for local max.
iters - Number of cleaning iterations to perform.

Optional Input Parameters

Keyword Input Parameters

CROSS - If set to a number greater than or equal to 0, the peak at
each iteration is found by using a cross-correlation
of the psf against the image rather than just using raw DN.
If 0, then the full size of the psf is used. If 1 or greater,
a sub-region from the center that is 2*CROSS+1 pixels square
is used as the convolution kernal.
DISPLAY - Display intermediate results, if 0, this is suppressed,
if non-zero, this is the interval for the display, that is,
DISPLAY=10 would cause a display every 10th iteration.
GAIN - "Gain" of the clean process, the default value is 0.05 and
is the scaled amount of the psf removed at each step.
VERBOSE - Verbose printout of intermediate steps to the screen. Just
like display, VERBOSE=0 suppresses output, VERBOSE=n will
print information every nth iteration.

Outputs

new_image - Clean-ed image result.
resid - Remains of the original image after clean-ed image is removed.

Keyword Output Parameters

Common Blocks

Side Effects

Restrictions

Procedure

Modification History

1/26/94, written by Marc W. Buie, Lowell Observatory, algorithmic insight
graciously provided by Tod Lauer (NOAO, Tucson).
2/25/94, MWB, added GAIN and CROSS keywords.
5/19/94, MWB, changed psf normalization from peak to total. Should
now be strictly flux conserving.
5/21/94, MWB, Changed CROSS to allow for only a portion of psf for
convolution.