NAME

       fitrans - performing spatial transformations on the input image

SYNOPSIS

       fitrans [transformation and options] <input> [-o|--output <output>]

DESCRIPTION

       The main purpose of this program is to perform specific or generic geometric transformations on the input
       image.

OPTIONS

   General options:
       -h, --help
              Gives general summary about the command line options.

       --long-help, --help-long
              Gives a detailed list of command line options.

       --wiki-help, --help-wiki, --mediawiki-help, --help-mediawiki
              Gives a detailed list of command line options in Mediawiki format.

       --version, --version-short, --short-version
              Gives some version information about the program.

       -i, --input <image file>
              Name of the input FITS image file.

       -o, --output <image file>
              Name of the output FITS image file.

       -b, --bitpix <bitpix>
              Standard FITS output bitpix value.

       -D, --data <spec>
              Output pixel data format specification.

   Spatial transformations:
       -T, --input-transformation <transformation file>
              Name of the file which contains the transformation description.Such a file can be created e.g.  by
              the  programs  `grtrans`  or  `grmatch`.  This file contains basically the same set of <keyword> =
              <value> pairs as it is used after the -t|--transformation option (see there).

       -t, --transformation <transformation>
              Comma-separated list of parameters for the spatial transformation,  see  section  "Parameters  for
              spatial transformations" below.

       -e, --shift <dx>,<dy>
              Imply a transformation that shifts the image by <dx>,<dy>.

       --reverse, --inverse
              Apply the inverse transformation to the image rather than the original one.

       -m     Simple linear interpolation between pixels, with no exact flux conservation (just a multiplication
              by the Jacobian of the transformation).

       -l     Linear interpolation between the pixels involving exact flux conservation by  integrating  on  the
              image surface.

       -c     Bicubic   spline   interpolation   between  pixels,  with  no  exact  flux  conservation  (just  a
              multiplication by the Jacobian of the transformation).

       -k     Interpolation by integrationg the flux on a biquadratic interpolation surface, yielding exact flux
              conservation.

       -s, --size <sx>,<sy>
              The size of the output image if it should differ from the original image size.

       -f, --offset <x>,<y>
              Zero-point coordinate of the output image in the input image.

   Parameters for spatial transformations:
       type=<type>
              Type  of  the  transformation.  In  the  actual  implementation,  the  only  supported  type for a
              transformation is "polynomial".

       order=<order>
              Polynomial order for the transformation.

       dxfit=<coefficients>
              Comma-separated list  of  the  polynomial  coefficients  for  the  X  coordinate.  The  number  of
              coefficients must be 1, 3, 6, ... for the orders 0, 1, 2, ... respectively.

       dyfit=<coefficients>
              Comma-separated list of the polynomial coefficients for the Y coordinate.

   Other simple spatial geometric transformations:
       -z, --zoom <factor>
              Zoom the image by the given (integer) factor, involving a biquadratic subpixel-level interpolation
              and therefore exact flux conservation.

       -r, --shrink <factor>
              Shrink the image by the given (integer) factor.

       -d, --median
              Use a median-based averaging during the shrinking operation.

       --optimistic-masking
              Imply some optimism during the shrinking operation: masked pixels are ignored during the averaging
              process and the final mask will be computed in a complement manner.

       -g, --magnify <factor>
              Same as zooming the image but there is no subpixel-level interpolation.

   Large-scale image smoothing:
       -a, --smooth <parameters>
              Perform a smoothing on the image. The parameters of the smoothing are the following:

       spline Do a spline interpolation smoothing

       polynomial
              Do a polynomial interpolation smoothing

       [xy]order=<order>
              Spatial  order  of  the  smoothing  function.  The  order  in  the  X and Y coordinates can be set
              independently, by setting "xorder=..." or "yorder=...".

       unity  Scale the resulting smoothed image to have a mean of 1.

       detrend
              The resulting image will be the original image divided by the best fit smoothed surface.

       [xy]hsize=<halfsize>
              Do a box filtering  with the given halfsize.

       mean   Use the mean value of the pixels for the box filtering.

       median Use the median value of the pixels for the box filtering.

       iterations=<iterations>
              Number of iterations to reject outlier pixels from the box.

       lower, upper, sigma=<sigma>
              Lower, upper or symmetric rejection level in the units of standard deviation.

   Noise estimation:
       -n, --noise
              Derive an image which reflects the "noise level" of the image.

   Slicing or exploding data cube images:
       -y, --layer <layer>
              Layer (z-axis index) of the desired image slice.

       -x, --explode <basename>
              Explode the input image into individual planar (two dimensional) FITS  image.  The  basename  must
              contain  at  least one printf-like tag of %d, %i, %o, %x or %X that is replaced by the appropriate
              layer number index.

       -y, --first-layer <n>
              Use the specified value for the first layer index. The subsequent layer  indices  are  incremented
              normally. By default, the index of the first data cube layer is 0.

REPORTING BUGS

       Report bugs to <apal@szofi.net>, see also http://fitsh.net/.

COPYRIGHT

       Copyright © 1996, 2002, 2004-2008, 2010-2015; Pal, Andras <apal@szofi.net>