src/tiff/man/tiffmedian.1

.\" $Id: tiffmedian.1,v 1.3 2005/11/02 11:07:19 dron Exp $
.\"
.\" Copyright (c) 1990-1997 Sam Leffler
.\" Copyright (c) 1991-1997 Silicon Graphics, Inc.
.\"
.\" Permission to use, copy, modify, distribute, and sell this software and
.\" its documentation for any purpose is hereby granted without fee, provided
.\" that (i) the above copyright notices and this permission notice appear in
.\" all copies of the software and related documentation, and (ii) the names of
.\" Sam Leffler and Silicon Graphics may not be used in any advertising or
.\" publicity relating to the software without the specific, prior written
.\" permission of Sam Leffler and Silicon Graphics.
.\"
.\" THE SOFTWARE IS PROVIDED "AS-IS" AND WITHOUT WARRANTY OF ANY KIND,
.\" EXPRESS, IMPLIED OR OTHERWISE, INCLUDING WITHOUT LIMITATION, ANY
.\" WARRANTY OF MERCHANTABILITY OR FITNESS FOR A PARTICULAR PURPOSE.
.\"
.\" IN NO EVENT SHALL SAM LEFFLER OR SILICON GRAPHICS BE LIABLE FOR
.\" ANY SPECIAL, INCIDENTAL, INDIRECT OR CONSEQUENTIAL DAMAGES OF ANY KIND,
.\" OR ANY DAMAGES WHATSOEVER RESULTING FROM LOSS OF USE, DATA OR PROFITS,
.\" WHETHER OR NOT ADVISED OF THE POSSIBILITY OF DAMAGE, AND ON ANY THEORY OF
.\" LIABILITY, ARISING OUT OF OR IN CONNECTION WITH THE USE OR PERFORMANCE
.\" OF THIS SOFTWARE.
.\"
.if n .po 0
.TH TIFFMEDIAN 1 "November 2, 2005" "libtiff"
.SH NAME
tiffmedian \- apply the median cut algorithm to data in a
.SM TIFF
file
.SH SYNOPSIS
.B tiffmedian
[
.I options
]
.I input.tif
.I output.tif
.SH DESCRIPTION
.I tiffmedian
applies the median cut algorithm to an
.SM RGB
image in
.I input.tif
to generate a palette image that is written to
.IR output.tif .
The generated colormap has, by default, 256 entries.
The image data is quantized by mapping each
pixel to the closest color values in the colormap.
.SH OPTIONS
.TP
.B \-c
Specify the compression to use for data written to the output file:
.B none
for no compression,
.B packbits
for PackBits compression,
.B lzw
for Lempel-Ziv & Welch compression,
and
.B zip
for Deflate compression.
By default
.I tiffmedian
will compress data according to the value of the
.I Compression
tag found in the source file.
.IP
.SM LZW
compression can be specified together with a
.I predictor
value.
A predictor value of 2 causes
each scanline of the output image to undergo horizontal
differencing before it is encoded; a value
of 1 forces each scanline to be encoded without differencing.
LZW-specific options are specified by appending a ``:''-separated
list to the ``lzw'' option; e.g.
.B "\-c lzw:2"
for
.SM LZW
compression with horizontal differencing.
.TP
.B \-C
Specify the number of entries to use in the generated colormap.
By default all 256 entries/colors are used.
.TP
.B \-f
Apply Floyd-Steinberg dithering before selecting a colormap entry.
.TP
.B \-r
Specify the number of rows (scanlines) in each strip of data
written to the output file.
By default,
.I tiffmedian
attempts to set the rows/strip
that no more than 8 kilobytes of data appear in a strip.
.SH NOTES
This program is derived from Paul Heckbert's
.I median
program.
.SH "SEE ALSO"
.BR pal2rgb (1),
.BR tiffinfo (1),
.BR tiffcp (1),
.BR tiffcmp (1),
.BR libtiff (3TIFF)
.PP
.BR "Color Image Quantization for Frame Buffer Display",
Paul Heckbert, SIGGRAPH proceedings, 1982, pp. 297-307.
.PP
Libtiff library home page:
.BR http://www.remotesensing.org/libtiff/
Commit	Line	Data
	1	.\" $Id: tiffmedian.1,v 1.3 2005/11/02 11:07:19 dron Exp $
	2	.\"
	3	.\" Copyright (c) 1990-1997 Sam Leffler
	4	.\" Copyright (c) 1991-1997 Silicon Graphics, Inc.
	5	.\"
	6	.\" Permission to use, copy, modify, distribute, and sell this software and
	7	.\" its documentation for any purpose is hereby granted without fee, provided
	8	.\" that (i) the above copyright notices and this permission notice appear in
	9	.\" all copies of the software and related documentation, and (ii) the names of
	10	.\" Sam Leffler and Silicon Graphics may not be used in any advertising or
	11	.\" publicity relating to the software without the specific, prior written
	12	.\" permission of Sam Leffler and Silicon Graphics.
	13	.\"
	14	.\" THE SOFTWARE IS PROVIDED "AS-IS" AND WITHOUT WARRANTY OF ANY KIND,
	15	.\" EXPRESS, IMPLIED OR OTHERWISE, INCLUDING WITHOUT LIMITATION, ANY
	16	.\" WARRANTY OF MERCHANTABILITY OR FITNESS FOR A PARTICULAR PURPOSE.
	17	.\"
	18	.\" IN NO EVENT SHALL SAM LEFFLER OR SILICON GRAPHICS BE LIABLE FOR
	19	.\" ANY SPECIAL, INCIDENTAL, INDIRECT OR CONSEQUENTIAL DAMAGES OF ANY KIND,
	20	.\" OR ANY DAMAGES WHATSOEVER RESULTING FROM LOSS OF USE, DATA OR PROFITS,
	21	.\" WHETHER OR NOT ADVISED OF THE POSSIBILITY OF DAMAGE, AND ON ANY THEORY OF
	22	.\" LIABILITY, ARISING OUT OF OR IN CONNECTION WITH THE USE OR PERFORMANCE
	23	.\" OF THIS SOFTWARE.
	24	.\"
	25	.if n .po 0
	26	.TH TIFFMEDIAN 1 "November 2, 2005" "libtiff"
	27	.SH NAME
	28	tiffmedian \- apply the median cut algorithm to data in a
	29	.SM TIFF
	30	file
	31	.SH SYNOPSIS
	32	.B tiffmedian
	33	[
	34	.I options
	35	]
	36	.I input.tif
	37	.I output.tif
	38	.SH DESCRIPTION
	39	.I tiffmedian
	40	applies the median cut algorithm to an
	41	.SM RGB
	42	image in
	43	.I input.tif
	44	to generate a palette image that is written to
	45	.IR output.tif .
	46	The generated colormap has, by default, 256 entries.
	47	The image data is quantized by mapping each
	48	pixel to the closest color values in the colormap.
	49	.SH OPTIONS
	50	.TP
	51	.B \-c
	52	Specify the compression to use for data written to the output file:
	53	.B none
	54	for no compression,
	55	.B packbits
	56	for PackBits compression,
	57	.B lzw
	58	for Lempel-Ziv & Welch compression,
	59	and
	60	.B zip
	61	for Deflate compression.
	62	By default
	63	.I tiffmedian
	64	will compress data according to the value of the
	65	.I Compression
	66	tag found in the source file.
	67	.IP
	68	.SM LZW
	69	compression can be specified together with a
	70	.I predictor
	71	value.
	72	A predictor value of 2 causes
	73	each scanline of the output image to undergo horizontal
	74	differencing before it is encoded; a value
	75	of 1 forces each scanline to be encoded without differencing.
	76	LZW-specific options are specified by appending a ``:''-separated
	77	list to the ``lzw'' option; e.g.
	78	.B "\-c lzw:2"
	79	for
	80	.SM LZW
	81	compression with horizontal differencing.
	82	.TP
	83	.B \-C
	84	Specify the number of entries to use in the generated colormap.
	85	By default all 256 entries/colors are used.
	86	.TP
	87	.B \-f
	88	Apply Floyd-Steinberg dithering before selecting a colormap entry.
	89	.TP
	90	.B \-r
	91	Specify the number of rows (scanlines) in each strip of data
	92	written to the output file.
	93	By default,
	94	.I tiffmedian
	95	attempts to set the rows/strip
	96	that no more than 8 kilobytes of data appear in a strip.
	97	.SH NOTES
	98	This program is derived from Paul Heckbert's
	99	.I median
	100	program.
	101	.SH "SEE ALSO"
	102	.BR pal2rgb (1),
	103	.BR tiffinfo (1),
	104	.BR tiffcp (1),
	105	.BR tiffcmp (1),
	106	.BR libtiff (3TIFF)
	107	.PP
	108	.BR "Color Image Quantization for Frame Buffer Display",
	109	Paul Heckbert, SIGGRAPH proceedings, 1982, pp. 297-307.
	110	.PP
	111	Libtiff library home page:
	112	.BR http://www.remotesensing.org/libtiff/