Provided by: montage_4.0+dfsg-3_amd64 
NAME
mHdrtbl - Generate metadata from a set of header files
SYNOPSIS
mHdrtbl [-rcdb] [-s statusfile] [-t imglist] directory images.tbl
DESCRIPTION
mHdrtbl operates in a fashion similar to mImgtbl, but is used on a set of header template
files instead of FITS images.
OPTIONS
-r mHdrtbl can also be used as a standalone program to gather image metadata for other
purposes (to populate a database, as a basis for spatial coverage searches, etc.)
In this case it is often desirable to collect information on all the files in a
directory tree recursively. The "-r" (recursive) flag instructs mHdrtbl to search
the given directory and all its subdirectories recursively.
-c The "-c" (corners) option in mHdrtbl will cause eight extra columns to be added to
the output metadata table containing the RA, Dec coordinates (ra1, dec1, ... ra4,
dec4) of the image corners. The output is always Equatorial J2000, even if the
input is some other system. This has been done to make the metadata uniform so
that it can easily be used for coverage searches, etc. The "-c" option is not
needed for normal Montage processing.
-d Turn on debugging
-b When this switch is set, mHdrtbl will explicitly output each header file it finds
that does not appear to be valid, along with information on the error.
-s statusfile
Output and errors are written to statusfile instead of being written to stdout.
-t imglist
mHdrtbl will only process files with names specified in table imglist, ignoring any
other files in the directory. Example: example.imglist.
ARGUMENTS
directory
Path to directory containing set of input header templates.
images.tbl
Path of output metadata table.
RESULT
Output table contains metadata information from all readable header templates in the
directory specified by directory. count is the number of records in the table, and
badhdrs is the number of files for which FITS/WCS metadata could not be extracted.
OUTPUT COLUMNS
cntr A unique counter (row number)
ra,dec Image position in decimal degree format
cra,cdec
Right ascension in HHMMSS.SS format. Declination in DDMMSS.S format
naxis1, naxis2
The size of the image in pixels for dimensions 1 and 2
ctype1, ctype2
The coordinate system (the first four characters) and WCS map projection (last
three characters) for dimensions 1 and 2
crpix1, crpix2
The pixel coordinates of the reference location (can be fractional and can be off
the image) for dimensions 1 and 2
crval1, crval2
The coordinates of a reference location on the sky (often at the center of the
image) for dimensions 1 and 2
cdelt1, cdelt2
The pixel scale (in degrees on the sky per pixel) at the reference location for
dimensions 1 and 2
crota2 The rotation angle from the "up" direction to the celestial pole
equinox
Precessional year associated with the coordinate system
hdu Numerical identifier for the FITS extension that the image info is extracted from,
for FITS files with multiple HDUs.
size Filesize (in bytes) of the input FITS file
fname The path to the input FITS file
MESSAGES
OK [struct stat="OK", count=count, badfits=badfits]
ERROR Illegal argument: -arg
ERROR Cannot open status file: statusfile
ERROR Cannot open field list file: fieldlistfile
ERROR Cannot open image list file: imgfile
ERROR Image table needs column fname/file
ERROR Illegal field name: string]
ERROR Illegal field type: string]
ERROR Cannot access directory
ERROR directory is not a directory
ERROR Can't open output table.
ERROR Can't open copy table.
ERROR Can't open tmp (in) table.
ERROR Can't open tmp (out) table.
ERROR Can't open final table.
ERROR FITS library error
EXAMPLES
The following example runs mHdrtbl on a directory containing header templates stripped
from 14 2MASS images:
$ mHdrtbl input/2mass headers.tbl
[struct stat="OK", count=14, badfits=0]
Output: headers.tbl.
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.