man mConvert (1): Convert FITS data to a different data type (ie, integer to floating-point)

SYNOPSIS

mConvert [-d level] [-s statusfile] [-b bitpix] [-min minval] [-max maxval] [-blank blankval] in.fits out.fits

DESCRIPTION

mConvert changes the datatype of an image. When converting to floating point, no additional information is needed. However, when converting from higher precision (e.g. 64-bit floating point) to lower (e.g. 16-bit integer), scaling information is necessary. This can be given explicitly by the user or guessed by the program.

OPTIONS

-d level: Turns on debugging to the specified level (1-3).
-s statusfile: mBgModel output and errors are written to statusfile instead of to stdout.
-b bitpix: BITPIX value for the output FITS file (default is -64). Possible values are:

      8 (character or unsigned binary integer)
      16 (16-bit integer)
      32 (32-bit integer)
      -32 (single precision floating point)
      -64 (double precision floating point).
-min minval: Pixel data value in the input image which should be treated as a minimum (value of 0) in the output image when converting from floating point to integer. (default for BITPIX 8: 0; BITPIX 16: -32767; BITPIX 32: -2147483647
-max maxval: Pixel data value in the input image which should be treated as a maximum (value of 255 or 32768) in the output image when converting from floating point to integer. (Default for BITPIX 8: 255; BITPIX 16: 32768; BITPIX 32: 2147483648)
-blank blankval: If converting down to an integer scale: value to be used in the output image to represent blank pixels (NaN) from the input image. Default value is minval.

ARGUMENTS

in.fits: Input image filename
out.fits: Output image filename.

RESULT

Output image with the datatype as specified by the user (BITPIX).

MESSAGES

OK: [struct stat="OK"]
ERROR: No status file name given
ERROR: Cannot open status file: statusfile
ERROR: No debug level given
ERROR: Debug level string is invalid: 'debug-level'
ERROR: Debug level value cannot be negative
ERROR: No bitpix value given
ERROR: Bitpix string is invalid: 'bitpix'
ERROR: Bitpix must be one of (8, 16, 32, -32, -64)
ERROR: No range min value given
ERROR: Range min string is invalid: 'min'
ERROR: No range max value given
ERROR: Range max string is invalid: 'max'
ERROR: No blank value given
ERROR: Blank string is invalid: 'blank'
ERROR: Invalid input file 'in.fits'
ERROR: Invalid output file 'out.fits'
ERROR: general error message
ERROR: FITS library error message

EXAMPLES

Converting a single-precision image down to a 16-bit integer BITPIX, when the data is clustered between values of -0.01 and 0.1:

$ mConvert -b 16 -min -0.01 -max 0.1 -blank -32767 acs.fits acs_bitpix16.fits: [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.