NAME
      unexp - Convert "exponential" files into
      normal files.

 SYNOPSIS
      unexp [ -m maxval ] [ -o outfile ] [ -p ] [ -s ] [ -v ] infile

 DESCRIPTION
      Unexp Converts a file of "exponential"
      floating point values into an RLE(5) file
      containing integer valued bytes.  Exponential
      files have N-1 channels of eight bit data,
      with the Nth channel containing a common
      exponent for the other channels.  This allows
      the values represented by the pixels to have
      a wider dynamic range.

      If no maximum value is specified, unexp first
      reads the RLE file to find the dynamic range
      of the whole file.  It then rewinds the file
      and scales the output to fit within that
      dynamic range.  If a maximum value is
      specified, unexp runs in one pass, and clamps
      any values exceeding the maximum.

      Files containing exponential data are
      expected to have a "exponential_data"
      comment; unexp prints a warning if such a
      comment doesn't exist.  An exponential file
      should be unexp'ed before attempting to use
      any tools that perform arithmetic on pixels
      (e.g., rlecomp(1), avg4(1), fant(1), or
      applymap(1)) or displaying the image.

      Unexp does not allow piped input.  The infile
      must be a real file; the special filenames
      described in urt(1) are not allowed.  ("-"
      does work, as long as the input is coming
      from a real file; this is of minimal utility,
      therefore, as typing unexp - <foo.rle is
      harder than typing unexp foo.rle.)

 OPTIONS
      -m maxval
           Specify the maximum value (i.e., the
           data in the file is assumed to be in the
           range 0..maxval).  Only the conversion
           pass is executed, and values found
           exceeding the maximum are clamped.

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      -o outfile
           If specified, the output will be written
           to this file.  If outfile is "-", or if
           it is not specified, the output will be
           written to the standard output stream.

      -p   Print the maximum value found during the
           scanning phase

      -s   Just scan the file to find the maximum,
           don't generate any output.

      -v   Verbose mode, print a message to stderr
           after scanning or converting every
           hundred scanlines.

 SEE ALSO
      float_to_exp(3), urt(1), RLE(5).

 AUTHOR
      John W. Peterson

 BUGS
      Unexp is provided because of the lack of
      floating point or extended precision RLE
      files.

      The -v flag is a historical relict from the
      slow CPU days.





















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