NAME

       mSubimage - Create a "cutout" of a FITS image

SYNOPSIS

       mSubimage [-d] [-a] [-h hdu] [-s statusfile] in.fits out.fits ra dec xsize [ysize]

       mSubimage -p [-d] [-h hdu] [-s statusfile] in.fits out.fits xstartpix ystartpix xpixsize [ypixsize]

DESCRIPTION

       Creates  a  subimage  (or  "cutout")  of  a  FITS  file.   Note that in "normal" mode, all the parameters
       (location and size) are in degrees; in pixel (-p) mode, all of them are in pixels

OPTIONS

       -d     Turns on debugging.

       -a     All pixels - Force retrieval of whole image (useful to extract an entire HDU)

       -h hdu Operate on the specified FITS header extension (HDU)

       -s statusfile
              Output and errors are sent to statusfile instead of to stdout

       -p     Pixel mode - create subimage using pixel locations, instead of a location on the sky

ARGUMENTS

       in.fits
              Input FITS file.

       out.fits
              Path to output FITS file.

       ra     In normal mode, RA of center of output image.

       dec    In normal mode, declination of center of output image.

       xstartpix
              In pixel mode, pixel along the x-axis where the cutout image will begin

       ystartpix
              In pixel mode, pixel along the y-axis where the cutout image will begin

       xsize  In normal mode, width of output image in degrees.

       ysize  In normal mode, height of output image in degrees (default is equal to xsize.

       xpixsize
              In pixel mode, width of output image in pixels

       ypixsize
              In pixel mode, height of output image in pixels (default is equal to xpixsize

RESULT

       [struct stat="OK", content="blank, flat or normal"]

       The content keyword indicates whether all pixels where NaN  (blank),  all  pixels  were  the  same  value
       (flat), or the image appears to be normal.

MESSAGES

       OK     [struct stat="OK", content="blank, flat or normal"]

       ERROR  HDU value (hdu) must be a non-negative integer

       ERROR  Cannot open status file: statusfile

       ERROR  Center RA string (string) cannot be interpreted as a real number

       ERROR  Center Dec string (string) cannot be interpreted as a real number

       ERROR  X size string (string) cannot be interpreted as a real number

       ERROR  Y size string (string) cannot be interpreted as a real number

       ERROR  Invalid 'x' size

       ERROR  Invalid 'y' size

       ERROR  Image file filename missing or invalid FITS

       ERROR  Cannot find HDU hdu

       ERROR  Output wcsinit() failed.

       ERROR  Location is off image

       ERROR  Region outside image

       ERROR  No pixels match area.

       ERROR  Can't create output file: out.fits

       ERROR  FITS library error

EXAMPLES

       $ mSubimage image1.fits subimage.fits 307.9 37.29 .01 .01
              [struct stat="OK", content="normal"]

BUGS

       The drizzle algorithm has been implemented but has not been tested in this release.

       If a header template contains carriage returns (i.e., created/modified on a Windows machine), the cfitsio
       library will be unable to read it properly, resulting in the  error:  [struct  stat="ERROR",  status=207,
       msg="illegal character in keyword"]

       It  is  best  for  the  background  correction  algorithms  if  the area described in the header template
       completely encloses all of the input images in their entirety. If parts of input images are "chopped off"
       by  the  header  template,  the  background correction will be affected. We recommend you use an expanded
       header for the reprojection and background modeling steps, returning to  the  originally  desired  header
       size  for  the  final  coaddition.  The  default background matching assumes that there are no non-linear
       background variations in the individual images (and therefore in the overlap differences).  If  there  is
       any  uncertainty  in  this  regard, it is safer to turn on the "level only" background matching (the "-l"
       flag in mBgModel.

COPYRIGHT

       2001-2015 California Institute of Technology, Pasadena, California

       If your research uses Montage, please include the following acknowledgement: "This research made  use  of
       Montage.  It  is  funded  by  the  National  Science  Foundation  under Grant Number ACI-1440620, and was
       previously funded by the National Aeronautics and Space Administration's Earth Science Technology Office,
       Computation  Technologies  Project,  under  Cooperative  Agreement  Number  NCC5-626 between NASA and the
       California Institute of Technology."

       The Montage distribution includes an adaptation of the MOPEX algorithm developed at the  Spitzer  Science
       Center.