NAME

       mPad - None

SYNOPSIS

       mPad  [-nowcs][-d  level][-val  NaN-value][-bar  xmin  xmax  ymin  ymax  histfile] in.fits
       out.fits left right top bottom

DESCRIPTION

       Occasionally we want to pad the border of an image so that there is room for annotation, a
       color  bar,  or  just  for visual effect.  mPad does this and if a color bar is desired it
       adds one (wherever the user specifies, which might be in the pad  or  might  be  over  the
       image).

       The  pad  around  the  edges  is filled with NULLS (which will be rendered the same as the
       minimum in the color table but mJPEG/mViewer).  However the user can optionally have NULLs
       translated to another value with the "-val" argument.

OPTIONS

       -nowcs

              If  the image has WCS values in the header, these need to be adjusted to compensate
              for the padding.  This flag is used to tell the software that the  image  does  not
              contain WCS keywords so not to try.

       -d level

              Set debugging level (default none)

       -val NaN-value

              Value to which NULL pixels should be converted.

       -bar xmin xmax

              ymin ymax

              histfile

              Adding a color bar as part of the image is a little trickier than it might at first
              seem.

              A color bar is a rectangular region of pixels whose data values are set so that  it
              gives  the impression of the lookup-table used to render the image.  To do this, we
              need the image histogram  that  mViewer  (or  whatever  renderer)  would  use  when
              displaying the data.

              The  easiest way to do this is to 1) use mHistogram to generate the stretchl 2) use
              mPad to add the pixel array (usually in a pad  added  around  the  outside  of  the
              image(; and 3) use mViewer with the same pre-build histogram to render the image.

ARGUMENTS

       in.fits

              Original FITS image.

       out.fits

              Padded FITS image.

       left right top bottom

              Number of pixels with which to pad the four sides of the image.

RESULT

       If  successful,  the  result  is  a  new image almost identical to the original but padded
       around the edges and possibly containing an embedded color bar.   When  sent  to  mViewer,
       that tool can optionally add annotation to the bar.

MESSAGES

       ERROR  No debug level given

       ERROR  Debug level string is invalid: 'badstring'

       ERROR  Debug level value cannot be negative

       ERROR  Not enough information given to draw color bar

       ERROR  Bar X min string is invalid: 'badstring'

       ERROR  Bar X max string is invalid: 'badstring'

       ERROR  Bar Y min string is invalid: 'badstring'

       ERROR  Bar Y max string is invalid: 'badstring'

       ERROR  Cannot open histogram file badfile

       ERROR  No value given for NaN conversion

       ERROR  NaN conversion value string is invalid: 'badstring'

       ERROR  FITS library error

       ERROR  general error message

EXAMPLES

       (mHistogram -file SDSS_r.fits -2s max gaussian-log -out SDSS_r.hist)

              mPad  -bar  -100  -50 50 -50 SDSS_r.hist SDSS_r.fits sdss.fits 50 250 50 50 [struct
              stat="OK"]

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.