.\" $Id: TIFFswab.3tiff,v 1.2 2005/11/02 11:07:18 dron Exp $

.\"

.\" Copyright (c) 1988-1997 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 SWAB 3TIFF "November 04, 2004" "libtiff"

.SH NAME

TIFFGetBitRevTable, TIFFReverseBits, TIFFSwabShort, TIFFSwabLong,

TIFFSwabArrayOfShort, TIFFSwabArrayOfLong \- byte- and bit-swapping routines

.SH SYNOPSIS

.B "#include <tiffio.h>"

.sp

.BI "const unsigned char* TIFFGetBitRevTable(int " reversed ")"

.br

.BI "void TIFFReverseBits(u_char *" data ", unsigned long " nbytes ")"

.br

.BI "void TIFFSwabShort(uint16 *" data ")"

.br

.BI "void TIFFSwabLong(uint32 *" data ")"

.br

.BI "void TIFFSwabArrayOfShort(uint16 *" data ", unsigned long " nshorts ")"

.br

.BI "void TIFFSwabArrayOfLong(uint32 *" data ", unsigned long " nlongs ")"

.SH DESCRIPTION

The following routines are used by the library to swap

16- and 32-bit data and to reverse the order of bits in bytes.

.PP

.IR TIFFSwabShort

and

.IR TIFFSwabLong

swap the bytes in a single 16-bit and 32-bit item, respectively.

.IR TIFFSwabArrayOfShort

and

.IR TIFFSwabArrayOfLong

swap the bytes in an array of 16-bit and 32-bit items, respectively.

.PP

.IR TIFFReverseBits

replaces each byte in

.I data

with the equivalent bit-reversed value. This operation is performed with a

lookup table, which is returned using the

.IR TIFFGetBitRevTable

function.

.I reversed

parameter specifies which table should be returned. Supply

.I 1

if you want bit reversal table. Supply

.I 0

to get the table that do not reverse bit values. It is a lookup table that can

be used as an

.IR "identity function" ;

i.e.

.IR "TIFFNoBitRevTable[n] == n" .

.SH DIAGNOSTICS

None.

.SH "SEE ALSO"

.BR libtiff (3TIFF)

.PP

Libtiff library home page:

.BR http://www.remotesensing.org/libtiff/