Name
       thresh - threshold a cube/image to another cube/image or pixel map

Synopsis
       thresh [options] <in> [out]

Description
       thresh  uses  the  same  operation (thresholding) to give two different
       kind of results.  To get rid of peaks in a cube  for  example  (impulse
       noise,  etc.),  just  give  it the minimum and maximum values you want.
       Values out of this interval are clipped to the given extremums.  Pixels
       lying in the interval remain unchanged.

       You  can  clip  values outside an interval to specified values by using
       the -c and -C options.

       In binary mode, the input must be a single image, and the output  is  a
       binary  image set to 1 for a pixel lying in the interval and 0 outside.
       Use it to fix bad pixel maps from a linear gain image for example.

       Default mode is : thresholding to normal pixel values.

       Default output name for file infile.fits is infile.thr.fits

Options
       -b or --binary
              Changes mode to binary. Input cube must  have  only  one  image,
              output is a pixel map.

       -h or --highcut value
              Fixes the high cut value.

       -l or --lowcut value
              Fixes the low cut value.

       -c or --assignlow pixelvalue
              assigns  a  value for pixels which lie under lowcut. Defaults to
              lowcut itself.

       -C or --assignhigh pixelvalue
              assigns a value for pixels which lie above highcut. Defaults  to
              highcut itself.

Examples
       To  threshold  all  values outside the interval [12 ; 5000] in the file
       in.fits, you would use:

       > thresh -l 12 -h 5000 in.fits
       Output file in this case is in.thr.fits

       To set all values outside the interval [15 ; 1200] to  0  in  the  file
       in.fits, and to output it into a file named thd.fits, you would use:

       > thresh -l 15 -c 0 -h 1200 -C 0 in.fits thd.fits

Files
       Input files shall all comply with FITS format.

See Also
       flat