opensolaris man page for tiffdither

tiffdither(1)							   User Commands						     tiffdither(1)

NAME
       tiffdither - convert a grayscale image to bilevel using dithering

SYNOPSIS
       tiffdither [options] input.tif output.tif

DESCRIPTION
       tiffdither converts a single-channel 8-bit grayscale image to a bilevel image using Floyd-Steinberg error propagation with thresholding.

OPTIONS
       The following options are supported:

       -c	       Specify a compression scheme to use when writing image data:

		       -c g3		       CCITT Group 3 compression algorithm.

		       -c g4		       CCITT Group 4 compression algorithm.

		       -c lzw		       Lempel-Ziv and Welch algorithm.

		       -c none		       No compression.

		       -c packbits	       PackBits compression algorithm.

		       -c zip		       Deflate compression algorithm.

		       By default, tiffdither compresses data according to the value of the Compression tag found in the source file.

       -f	       Specify	the bit fill order to use to write output data. By default, tiffdither creates a new file with the same fill order
		       as the original. Specify -f lsb2msb to force data to be written with the FillOrder tag set to LSB2MSB. Specify  -f  msb2lsb
		       to force data to be written with the FillOrder tag set to MSB2LSB.

       -t	       Set the threshold value for dithering. By default, the threshold value is 128.

OPERANDS
       The following operands are supported:

       input.tif       The name of the input file.

       output.tif      The name of the output file.

EXTENDED DESCRIPTION
       The CCITT Group 3 and Group 4 compression algorithms can only be used with bilevel data.

       Group 3 compression can be specified together with several T.4-specific options:

       1d		       1-dimensional encoding

       2d		       2-dimensional encoding

       fill		       Force each encoded scanline to be zero-filled so that the terminating EOL code lies on a byte boundary.

       Group  3-specific options are specified by appending a colon-separated list to the g3 option. For example, specify -c g3:2d:fill to get 2D-
       encoded data with byte-aligned EOL codes.

       LZW compression can be specified together with a predictor value. A predictor value of 2 causes	each  scanline	of  the  output  image	to
       undergo horizontal differencing before being encoded. A predictor value of 1 forces each scanline to be encoded without differencing.

       LZW-specific options are specified by appending a colon-separated list to the lzw option. For example, specify -c lzw:2 for LZW compression
       with horizontal differencing.

ATTRIBUTES
       See attributes(5) for descriptions of the following attributes:

       +-----------------------------+-----------------------------+
       |      ATTRIBUTE TYPE	     |	    ATTRIBUTE VALUE	   |
       +-----------------------------+-----------------------------+
       |Availability		     |SUNWTiff			   |
       +-----------------------------+-----------------------------+
       |Interface stability	     |Uncommitted		   |
       +-----------------------------+-----------------------------+

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

NOTES
       Updated by Breda McColgan, Sun Microsystems Inc., 2004.

SunOS 5.11							    26 Mar 2004 						     tiffdither(1)