TIFFDITHER(1)             UNIX System V(May 18, 1991)             TIFFDITHER(1)


NAME
      tiffdither - convert a grayscale image to bilevel using dithering

SYNOPSIS
      tiffdither [ -f ] [ -4 ] [ -2 ] [ -o ] [ -p ] [ -t threshold ] file1
      file2

DESCRIPTION
      Tiffdither converts a single channel 8-bit grayscale image to a bilevel
      image using Floyd-Steinberg error propagation with threholding.  By
      default the threshold value is 128; this can be changed with the -t
      option.

      By default, the data in the resultant image are encoded with
      LZWcompression.  If the -f option is specified, the data are encoded with
      CCITT Group 3 facsimile encoding.  If the -4 option is specified, the
      data are encoded with CCITT Group 4 facsimile encoding.  The -o, -2, and
      -p options are useful only when the -f option is used; they reverse the
      default LSB to MSB bit ordering in the output file, force 2D encoding,
      and force zero-padding before EOL codes, respectively.

NOTES
      The dither algorithm is taken from the tiffmedian(1) program (written by
      Paul Heckbert).

SEE ALSO
      pal2rgb(1), fax2tiff(1), tiffinfo(1), tiffcp(1), tiff2bw(1), libtiff(3)



























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