NAME

       tiff2bw - convert a color TIFF image to greyscale

SYNOPSIS

       tiff2bw [ options ] input.tif output.tif

DESCRIPTION

       tiff2bw  converts  an  RGB  or  Palette color TIFF image to a greyscale image by combining
       percentages of the red, green, and blue channels.  By default, output samples are  created
       by  taking  28% of the red channel, 59% of the green channel, and 11% of the blue channel.
       To alter these percentages, the -R, -G, and -B options may be used.

OPTIONS

       -c compress
              Specify a compression scheme to use  when  writing  image  data:  -c  none  for  no
              compression,  -c  packbits  for  the PackBits compression algorithm, -c zip for the
              Deflate compression algorithm, -c g3 for the CCITT Group 3  compression  algorithm,
              -c  g4  for  the CCITT Group 4 compression algorithm, -c lzw for Lempel-Ziv & Welch
              (the default).

       -r striprows
              Write data with a specified number of rows per strip;  by  default  the  number  of
              rows/strip is selected so that each strip is approximately 8 kilobytes.

       -R redperc
              Specify the percentage of the red channel to use (default 28).

       -G greenperc
              Specify the percentage of the green channel to use (default 59).

       -B blueperc
              Specify the percentage of the blue channel to use (default 11).

SEE ALSO

       pal2rgb (1), tiffinfo (1), tiffcp (1), tiffmedian (1), libtiff (3tiff),

AUTHOR

       LibTIFF contributors

COPYRIGHT

       1988-2023, LibTIFF contributors