83 lines
2.0 KiB
C
83 lines
2.0 KiB
C
/* @(#) Gamma-correct uchar image with factor gammafactor.
|
|
* @(#)
|
|
* @(#) int im_gammacorrect(in, out, exponent)
|
|
* @(#) IMAGE *in, *out;
|
|
* @(#) double exponent;
|
|
* @(#)
|
|
* @(#) Returns 0 on sucess and -1 on error
|
|
* @(#)
|
|
*
|
|
*
|
|
* Copyright: 1990, N. Dessipris.
|
|
*
|
|
* Written on: 19/07/1990
|
|
* Modified on:
|
|
* 19/6/95 JC
|
|
* - redone as library function
|
|
*/
|
|
|
|
/*
|
|
|
|
This file is part of VIPS.
|
|
|
|
VIPS is free software; you can redistribute it and/or modify
|
|
it under the terms of the GNU Lesser General Public License as published by
|
|
the Free Software Foundation; either version 2 of the License, or
|
|
(at your option) any later version.
|
|
|
|
This program is distributed in the hope that it will be useful,
|
|
but WITHOUT ANY WARRANTY; without even the implied warranty of
|
|
MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
|
|
GNU Lesser General Public License for more details.
|
|
|
|
You should have received a copy of the GNU Lesser General Public License
|
|
along with this program; if not, write to the Free Software
|
|
Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA
|
|
|
|
*/
|
|
|
|
/*
|
|
|
|
These files are distributed with VIPS - http://www.vips.ecs.soton.ac.uk
|
|
|
|
*/
|
|
|
|
#ifdef HAVE_CONFIG_H
|
|
#include <config.h>
|
|
#endif /*HAVE_CONFIG_H*/
|
|
#include <vips/intl.h>
|
|
|
|
#include <stdio.h>
|
|
|
|
#include <vips/vips.h>
|
|
|
|
#ifdef WITH_DMALLOC
|
|
#include <dmalloc.h>
|
|
#endif /*WITH_DMALLOC*/
|
|
|
|
int
|
|
im_gammacorrect( IMAGE *in, IMAGE *out, double exponent )
|
|
{
|
|
IMAGE *t1 = im_open_local( out, "im_gammacorrect:#1", "p" );
|
|
IMAGE *t2 = im_open_local( out, "im_gammacorrect:#2", "p" );
|
|
IMAGE *t3 = im_open_local( out, "im_gammacorrect:#2", "p" );
|
|
|
|
if( !t1 || !t2 || !t3 )
|
|
return( -1 );
|
|
|
|
if( im_piocheck( in, out ) )
|
|
return( -1 );
|
|
if( in->BandFmt != IM_BANDFMT_UCHAR ) {
|
|
im_errormsg( "im_gammacorrect: uchar images only" );
|
|
return( -1 );
|
|
}
|
|
|
|
if( im_identity( t1, 1 ) ||
|
|
im_powtra( t1, t2, exponent ) ||
|
|
im_scale( t2, t3 ) ||
|
|
im_maplut( in, out, t3 ) )
|
|
return( -1 );
|
|
|
|
return( 0 );
|
|
}
|