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