Level 2 Help for ROTATE

INP

A VICAR labelled image to be rotated.


OUT

A VICAR labelled image file to receive the rotated image.

If OUT is omitted, only the ROTATE2 (tiepoint computation step) is 
performed, and LGEOM is not invoked.  The parameter dataset 
ZZPAR is still created, so the user may run LGEOM with 
(See ROTATE.PDF.)


SIZE

The size field indicates which area of the input image is to be 
rotated.  The NL and NS parameters specify the size of the output image.


SL

The starting line of the size field.


SS

The starting sample of the size field.


NL

The number of lines in the size field.  Also, the number of lines in the
output image.


NS

The number of bytes in the size field.  Also, the number of bytes in the 
output image.


ANGLE

This is the only required parameter.  It specifies the number of degrees
clockwise from up to rotate the image.  May be positive or negative.


LINE

This is the line number of the center of rotation in the input image.
Default = .5 * (sl + nl) ...the center line of the picture.


SAMPLE

This is the sample number of the center of rotation in the input image.
Default = .5 * (ss + ns) ...the center sample of the picture.  (Note that the
sample values are expressed in units of pixels, not bytes.)


CENTER

This specifies the center of rotation in the output image.  Default is the 
same as that specified for or defaulted for the input image.  (Note that the
sample values are expressed in units of pixels, not bytes.)


NOINTERP

This specifies that no interpolation is to be performed during the GEOM.
In this case, the DN value of the point closest to the fractional line and
sample is used.  This method ("nearest neighbor") is somewhat faster, but is
not as accurate as the four point interpolation.  Default = NOINTERP.


IDSNAM

IDSNAM is an optional parameter which can be used to change the
default name of the Intermediate Data Set.  Primarily it can 
be used to change the directory specification.  


IDSNS

IDSNS is an optional parameter which may be used to change the number
of bytes per line in the Intermediate Data Set.  The only real purpose
of this parameter is to allow the user to "tune" LGEOM to obtain the
optimum speed.