Provided by: montage_6.0+dfsg-10build1_amd64 
NAME
mProjectCube - Reproject a single cube to a user specified scale and coordinate system
SYNOPSIS
mProjectCube [-z factor] [-d level] [-s statusfile] [-h hdu] [-x scale] [-w weightfile]
[-W fixed-weight] [-t threshold] [-X] [-e(nergy-mode)] [-f] in.fits out.fits hdr.template
DESCRIPTION
mProjectCube reprojects a single cube to the scale defined in a FITS header template file
(read more about header templates here). The program produces a pair of files: the
reprojected cube and an "area" image consisting of the fraction input pixel sky area that
went into each output pixel. The "drizzle" algorithm is implemented. The algorithm
proceeds by mapping pixel corners (as adjusted by drizzle, if called) from the input pixel
space to the output pixel space, calculating overlap area with each output pixel, and
accumulating an appropriate fraction of the input flux into the output cube pixels. In
addition, the appropriate fraction of the input pixel area is accumulated into the area
image pixels. Projection of points from input pixel space to output pixel space is
calculated in two steps: first map from input pixel space to sky coordinates; second map
from sky coordinates to output pixel space.
One situation that has happened often enough to warrant special note: It is possible to
define a FITS header with the reference location off the image. In particular, people
often reference cylindrical projections (e.g., CAR, CEA) to location (0.,0.) (e.g., the
Galactic center). This is not wrong in itself but does lead to extremely large pixel
offsets (e.g., in the hundreds of thousands). Related to this, if you extract a header
from an image with large offsets of this type, it is unlikely that you can simply change
projection types without also adjusting the reference location/offsets. Most likely, you
will end up witr the reprojected data all being off-scale.
OPTIONS
-z factor
Processing is done utilizing the drizzle algorithm. factor is a floating point
number; recommended drizzle factors are from 0.5 to 1.
-d level
Causes additional debugging information to be printed to stdout. Valid levels are
1-5 (for higher debugging levels, it is recommended to redirect the output to a
file).
-s statusfile
Output and errors are written to statusfile instead of being written to stdout.
-h hdu Use the specified FITS extension (default is to use the first HDU with image data)
-x scale
Apply a correction factor of scale to each pixel.
-w weightfile
Path to a weight map to be used when reading values from the input image.
-W fixed-weight
Use constant weight value for the whole image.
-t threshold
Pixels with weights below threshold will be treated as blank.
-X Makes the output region (originally defined in the header template) big enough to
include all of the input images.
-e Process the data as total energy rather than the default energy density (scale
values by relative pixel areas).
-f Output the full region requested even if there is a border of NULL values (default
is to shrinkwrap to just the pixels with values).
ARGUMENTS
in.fits
Input FITS file to be reprojected.
out.fits
Path of output FITS file to be created.
hdr.template
FITS header template to be used in generation of output image
RESULT
Two files are created as output: the reprojected FITS file (out.fits), and an "area" image
(out_area.fits) which records the amount of coverage (in output pixel space) provided by
the input images.
MESSAGES
OK [struct stat="OK", time=seconds]
ERROR Drizzle factor string (string) cannot be interpreted as a real number
ERROR Weight threshold string (string) cannot be interpreted as a real number
ERROR Flux scale string (string) cannot be interpreted as a real number
ERROR Cannot open status file: statusfile
ERROR HDU value (hdu) must be a non-negative integer
ERROR No overlap
ERROR Not enough memory for output data image array
ERROR Not enough memory for output area image array
ERROR Output wcsinit() failed.
ERROR Input wcsinit() failed.
ERROR FITS library error
ERROR All pixels are blank
ERROR Template file not found
ERROR Image file in.fits missing or invalid FITS
ERROR Weight file weightfile missing or invalid FITS
EXAMPLES
$ mProjectCube rawdir/real_orig.fits projdir/base_unity.fits templates/galactic_orig.txt
[struct stat="OK", time=143]
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.