'\" te
.TH tiffmedian 1 "26 Mar 2004" "SunOS 5.11" "User Commands"
.SH "NAME"
tiffmedian \- apply the median cut algorithm to data in a TIFF file
.SH "SYNOPSIS"
.PP
\fBtiffmedian\fR [\fB\fIoptions\fR\fR] \fB\fIinput\&.tif\fR\fR \fB\fIoutput\&.tif\fR\fR
.SH "DESCRIPTION"
.PP
\fBtiffmedian\fR applies the median cut algorithm to an RGB
image in \fB\fIinput\&.tif\fR\fR, to generate
a palette image that is written to \fB\fIoutput\&.tif\fR\fR\&.
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"
.PP
The following options are supported:
.sp
.ne 2
.mk
\fB-\fBc\fR\fR
.in +16n
.rt
Specify a compression
scheme to use when writing image data:
.sp
.sp
.ne 2
.mk
\fB-\fBc lzw\fR\fR
.in +24n
.rt
Lempel-Ziv
and Welch algorithm\&.
.sp
.sp 2
.in -24n
.sp
.ne 2
.mk
\fB-\fBc none\fR\fR
.in +24n
.rt
No compression\&.
.sp
.sp 1
.in -24n
.sp
.ne 2
.mk
\fB-\fBc packbits\fR\fR
.in +24n
.rt
PackBits
compression algorithm\&.
.sp
.sp 1
.in -24n
.sp
.ne 2
.mk
\fB-\fBc zip\fR\fR
.in +24n
.rt
Deflate compression
algorithm\&.
.sp
.sp 1
.in -24n
If no compression-related option is specified, the input-file
compression algorithm is used\&.
.sp
.sp 0
.in -16n
.sp
.ne 2
.mk
\fB-\fBC\fR\fR
.in +16n
.rt
Specify the number
of entries to use in the generated colormap\&. By default, all 256 entries or
colors are used\&.
.sp
.sp 1
.in -16n
.sp
.ne 2
.mk
\fB-\fBf\fR\fR
.in +16n
.rt
Apply Floyd-Steinberg
dithering before selecting a colormap entry\&.
.sp
.sp 1
.in -16n
.sp
.ne 2
.mk
\fB-\fBr\fR\fR
.in +16n
.rt
Write data with
a specified number of rows per strip\&. By default, the number of rows per strip
is selected so that each strip is approximately 8 kilobytes\&.
.sp
.sp 1
.in -16n
.SH "OPERANDS"
.PP
The following operands are supported:
.sp
.ne 2
.mk
\fB\fB\fIinput\&.tif\fR\fR\fR
.in +16n
.rt
The name of the input TIFF file\&.
.sp
.sp 1
.in -16n
.sp
.ne 2
.mk
\fB\fB\fIoutput\&.tif\fR\fR\fR
.in +16n
.rt
The name of the output file\&.
.sp
.sp 1
.in -16n
.SH "EXTENDED DESCRIPTION"
.PP
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\&.
.PP
LZW-specific options are specified by appending a colon-separated list
to the \fBlzw\fR option\&. For example, specify -\fBc\fR \fBlzw:2\fR for LZW compression with horizontal
differencing\&.
.SH "ATTRIBUTES"
.PP
See \fBattributes\fR(5)
for descriptions of the following attributes:
.sp
.TS
tab() allbox;
cw(2.750000i)| cw(2.750000i)
lw(2.750000i)| lw(2.750000i).
ATTRIBUTE TYPEATTRIBUTE VALUE
Availabilityimage/library/libtiff
Interface stabilityUncommitted
.TE
.sp
.SH "SEE ALSO"
.PP
\fIColor Image Quantization for Frame Buffer Display\fR,
Paul Heckbert, SIGGRAPH proceedings, 1982, pp\&. 297-307\&.
.PP
\fBpal2rgb\fR(1), \fBtiffinfo\fR(1), \fBtiffcp\fR(1), \fBtiffcmp\fR(1), \fBlibtiff\fR(3)
.SH "NOTES"
.PP
Updated by Breda McColgan, Sun Microsystems Inc\&., 2004\&.
...\" created by instant / solbook-to-man, Thu 20 Mar 2014, 02:30
...\" LSARC 2003/085 libtiff, libjpeg, and libpng