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.\" $Id: TIFFswab.3tiff,v 1.2 2005-11-02 11:07:18 dron Exp $
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.\"
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.\" Copyright (c) 1988-1997 Sam Leffler
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.\" Copyright (c) 1991-1997 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 SWAB 3TIFF "November 04, 2004" "libtiff"
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.SH NAME
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TIFFGetBitRevTable, TIFFReverseBits, TIFFSwabShort, TIFFSwabLong,
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TIFFSwabArrayOfShort, TIFFSwabArrayOfLong \- byte- and bit-swapping routines
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.SH SYNOPSIS
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.B "#include <tiffio.h>"</tiffio.h>
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.sp
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.BI "const unsigned char* TIFFGetBitRevTable(int " reversed ")"
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.br
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.BI "void TIFFReverseBits(u_char *" data ", unsigned long " nbytes ")"
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.br
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.BI "void TIFFSwabShort(uint16 *" data ")"
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.br
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.BI "void TIFFSwabLong(uint32 *" data ")"
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.br
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.BI "void TIFFSwabArrayOfShort(uint16 *" data ", unsigned long " nshorts ")"
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.br
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.BI "void TIFFSwabArrayOfLong(uint32 *" data ", unsigned long " nlongs ")"
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.SH DESCRIPTION
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The following routines are used by the library to swap
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16- and 32-bit data and to reverse the order of bits in bytes.
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.PP
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.IR TIFFSwabShort
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and
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.IR TIFFSwabLong
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swap the bytes in a single 16-bit and 32-bit item, respectively.
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.IR TIFFSwabArrayOfShort
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and
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.IR TIFFSwabArrayOfLong
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swap the bytes in an array of 16-bit and 32-bit items, respectively.
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.PP
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.IR TIFFReverseBits
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replaces each byte in
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.I data
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with the equivalent bit-reversed value. This operation is performed with a
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lookup table, which is returned using the
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.IR TIFFGetBitRevTable
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function.
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.I reversed
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parameter specifies which table should be returned. Supply
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.I 1
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if you want bit reversal table. Supply
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.I 0
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to get the table that do not reverse bit values. It is a lookup table that can
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be used as an
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.IR "identity function" ;
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i.e.
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.IR "TIFFNoBitRevTable[n] == n" .
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.SH DIAGNOSTICS
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None.
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.SH "SEE ALSO"
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.BR libtiff (3TIFF)
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.PP
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Libtiff library home page:
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.BR http://www.remotesensing.org/libtiff/