.TH MBGEXEC 1 "June 2010" "Montage 3.3" "Montage"
.SH NAME
mBgExec \- Run mBackground on all the images in a metadata table

.SH SYNOPSIS
mBgExec [\-p \fIprojdir\fP] [\-s \fIstatusfile\fP] [\-d] [\-n(o-areas)] images.tbl corrections.tbl corrdir

.SH DESCRIPTION
Runs mBackground on all the images in a metadata table, using the corrections generated by mFitExec.

.SH OPTIONS
.TP
\-p \fIprojdir\fP
Specifies the path to the directory containing the projected images.
.TP
\-s \fIstatusfile\fP
Writes output message to \fIstatusfile\fP instead of to stdout
.TP
\-d
Turns on debugging
.TP
\-n
Indicates that no area images are present (assumes equal weighting for each pixel)

.SH ARGUMENTS
.TP
images.tbl
Image metadata table generated by mImgtbl.
.TP
corrections.tbl
Table of corrections generated by mFitExec
.TP
corrdir
Directory where output images should be written

.SH RESULT
Output FITS images will be created in the directory specified by \fIcorrdir\fP, with names that are the same as the uncorrected images.

.SH MESSAGES
.TP
OK
[struct stat="OK", count=\fInum-images\fP, nocorrection=\fInum-skipped\fP, failed=\fInum-failed\fP]
.TP
ERROR
MPI initialization failed
.TP
ERROR
Cannot open status file: \fIstatusfile\fP
.TP
ERROR
Cannot access \fIcorrdir\fP
.TP
ERROR
\fIcorrdir\fP is not a directory
.TP
ERROR
Invalid image metadata file: \fIimages.tbl\fP
.TP
ERROR
Need columns: cntr and fname in image list
.TP
ERROR
Too many entries in image list for compiled program
.TP
ERROR
\fImBackground error\fP

.SH EXAMPLES
.PP
In this example, \fBimages.tbl\fP describes the unprojected or projected images (filenames are the same if \fBmProjExec\fP was used), and \fBcorrections.tbl\fP was generated using \fBmBgModel\fP after running \fBmDiffExec\fP and \fBmFitExec\fP on those images.
.TP
$ mBgExec \-p proj images.tbl corrections.tbl corr
[struct stat="OK", count=16, failed=0]
.PP
corr now contains the images with background removal applied.

.SH BUGS
The drizzle algorithm has been implemented but has not been tested
in this release.
.PP
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"]
.PP
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.

.SH COPYRIGHT
2001-2015 California Institute of Technology, Pasadena, California
.PP
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."
.PP
The Montage distribution includes an adaptation of the MOPEX algorithm
developed at the Spitzer Science Center.