thumbnail.1

tiff文件开发库

.\"	$Header: /cvsroot/osrs/libtiff/man/thumbnail.1,v 1.1.1.1 1999/07/27 21:50:28 mike Exp $
.\"
.\" Copyright (c) 1994-1997 Sam Leffler
.\" Copyright (c) 1994-1997 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 THUMBNAIL 1 "September 26, 1994"
.SH NAME
thumbnail \- create a
.SM TIFF
file with thumbnail images
.SH SYNOPSIS
.B thumbnail
[
.I options
]
.I input.tif
.I output.tif
.SH DESCRIPTION
.I thumbnail
is a program written to show how one might use the
SubIFD tag (#330) to store thumbnail images.
.I thumbnail
copies a
.SM TIFF
Class F facsimile file to the output file
and for each image an 8-bit greyscale 
.IR "thumbnail sketch" .
The output file contains the thumbnail image with the associated
full-resolution page linked below with the SubIFD tag.
.PP
By default, thumbnail images are 216 pixels wide by 274 pixels high.
Pixels are calculated by sampling and filtering the input image
with each pixel value passed through a contrast curve.
.SH OPTIONS
.TP
.B \-w
Specify the width of thumbnail images in pixels.
.TP
.B \-h
Specify the height of thumbnail images in pixels.
.TP
.B \-c
Specify a contrast curve to apply in generating the thumbnail images.
By default pixels values are passed through a linear contrast curve
that simply maps the pixel value ranges.
Alternative curves are:
.B exp50
for a 50% exponential curve,
.B exp60
for a 60% exponential curve,
.B exp70
for a 70% exponential curve,
.B exp80
for a 80% exponential curve,
.B exp90
for a 90% exponential curve,
.B exp
for a pure exponential curve,
.B linear
for a linear curve.
.SH BUGS
There are no options to control the format of the saved thumbnail images.
.SH "SEE ALSO"
.IR tiffdump (1),
.IR tiffgt (1),
.IR tiffinfo (1),
.IR libtiff (3)