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.\"	$Id: thumbnail.1,v 1.2 2005-11-02 11:07:19 dron Exp $
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.\"
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.\" Copyright (c) 1994-1997 Sam Leffler
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.\" Copyright (c) 1994-1997 Silicon Graphics, Inc.
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.\"
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.\" Permission to use, copy, modify, distribute, and sell this software and 
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.\" its documentation for any purpose is hereby granted without fee, provided
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.\" that (i) the above copyright notices and this permission notice appear in
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.\" all copies of the software and related documentation, and (ii) the names of
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.\" Sam Leffler and Silicon Graphics may not be used in any advertising or
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.\" publicity relating to the software without the specific, prior written
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.\" permission of Sam Leffler and Silicon Graphics.
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.\" 
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.\" THE SOFTWARE IS PROVIDED "AS-IS" AND WITHOUT WARRANTY OF ANY KIND, 
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.\" EXPRESS, IMPLIED OR OTHERWISE, INCLUDING WITHOUT LIMITATION, ANY 
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.\" WARRANTY OF MERCHANTABILITY OR FITNESS FOR A PARTICULAR PURPOSE.  
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.\" 
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.\" IN NO EVENT SHALL SAM LEFFLER OR SILICON GRAPHICS BE LIABLE FOR
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.\" ANY SPECIAL, INCIDENTAL, INDIRECT OR CONSEQUENTIAL DAMAGES OF ANY KIND,
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.\" OR ANY DAMAGES WHATSOEVER RESULTING FROM LOSS OF USE, DATA OR PROFITS,
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.\" WHETHER OR NOT ADVISED OF THE POSSIBILITY OF DAMAGE, AND ON ANY THEORY OF 
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.\" LIABILITY, ARISING OUT OF OR IN CONNECTION WITH THE USE OR PERFORMANCE 
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.\" OF THIS SOFTWARE.
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.\"
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.if n .po 0
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.TH THUMBNAIL 1 "November 2, 2005" "libtiff"
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.SH NAME
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thumbnail \- create a
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.SM TIFF
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file with thumbnail images
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.SH SYNOPSIS
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.B thumbnail
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[
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.I options
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]
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.I input.tif
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.I output.tif
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.SH DESCRIPTION
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.I thumbnail
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is a program written to show how one might use the
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SubIFD tag (#330) to store thumbnail images.
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.I thumbnail
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copies a
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.SM TIFF
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Class F facsimile file to the output file
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and for each image an 8-bit greyscale 
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.IR "thumbnail sketch" .
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The output file contains the thumbnail image with the associated
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full-resolution page linked below with the SubIFD tag.
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.PP
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By default, thumbnail images are 216 pixels wide by 274 pixels high.
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Pixels are calculated by sampling and filtering the input image
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with each pixel value passed through a contrast curve.
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.SH OPTIONS
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.TP
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.B \-w
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Specify the width of thumbnail images in pixels.
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.TP
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.B \-h
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Specify the height of thumbnail images in pixels.
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.TP
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.B \-c
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Specify a contrast curve to apply in generating the thumbnail images.
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By default pixels values are passed through a linear contrast curve
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that simply maps the pixel value ranges.
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Alternative curves are:
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.B exp50
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for a 50% exponential curve,
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.B exp60
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for a 60% exponential curve,
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.B exp70
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for a 70% exponential curve,
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.B exp80
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for a 80% exponential curve,
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.B exp90
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for a 90% exponential curve,
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.B exp
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for a pure exponential curve,
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.B linear
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for a linear curve.
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.SH BUGS
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There are no options to control the format of the saved thumbnail images.
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.SH "SEE ALSO"
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.BR tiffdump (1),
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.BR tiffgt (1),
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.BR tiffinfo (1),
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.BR libtiff (3)
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.PP
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Libtiff library home page:
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.BR http://www.remotesensing.org/libtiff/