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.