idlastro / Astronomical Utilities: GAL_FLAT

[Source code]

NAME
GAL_FLAT
PURPOSE
Transforms the image of a galaxy so that the galaxy appears face-on
EXPLANATION
Either a nearest-neighbor approximations or a bilinear interpolation 
may  be used.
CALLING SEQUENCE
RESULT = GAL_FLAT( image, ang, inc, [, cen, /INTERP ] )  
INPUTS
IMAGE  - Image to be transformed
ANG  - Angle of major axis, counterclockwise from Y-axis, degrees
        For an image in standard orientation (North up, East left)
        this is the Position Angle
INC - Angle of inclination of galaxy, degrees
OPTIONAL INPUTS
CEN - Two element vector giving the X and Y position of galaxy center
        If not supplied, then the galaxy center is assumed to coincide
         with the image center
INPUT KEYWORDS
INTERP - If present, and non-zero, then bilinear interpolation will be
        performed.  Otherwise a nearest neighbor approximation  is used.
OUTPUTS
RESULT - the transformed image, same dimensions and type as IMAGE
METHOD
A set of 4 equal spaced control points are corrected for inclination
using the procedure POLYWARP.   These control points are used by 
POLY_2D to correct the whole image.
REVISION HISTORY
Written by R. S. Hill, SASC Technologies Inc., 4 December 1985
Code cleaned up a bit    W. Landsman      December 1992
Converted to IDL V5.0   W. Landsman   September 1997