84 lines
2.0 KiB
C
84 lines
2.0 KiB
C
/* im_addgnoise
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*
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* Copyright 1990, N. Dessipris.
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*
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* File written on 2/12/1986
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* Author : N. Dessipris
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* Updated : 22/01/1991
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* 1/2/95 JC
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* - junked!
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* - now uses partial im_gaussnoise() and partial im_add() to do the
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* same job
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& 1/5/01 JC
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* - oops, failed for not-1-band images
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*
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* 2008-01-28 tcv:
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* - now works (was broken)
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* - no limit on bands
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* 4/2/10
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* - no need to bandup here now, im_add() does that
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* - gtkdoc
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*/
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/*
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This file is part of VIPS.
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VIPS is free software; you can redistribute it and/or modify
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it under the terms of the GNU Lesser General Public License as published by
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the Free Software Foundation; either version 2 of the License, or
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(at your option) any later version.
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This program is distributed in the hope that it will be useful,
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but WITHOUT ANY WARRANTY; without even the implied warranty of
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MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
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GNU Lesser General Public License for more details.
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You should have received a copy of the GNU Lesser General Public License
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along with this program; if not, write to the Free Software
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Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA
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02110-1301 USA
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*/
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/*
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These files are distributed with VIPS - http://www.vips.ecs.soton.ac.uk
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*/
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#ifdef HAVE_CONFIG_H
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#include <config.h>
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#endif /*HAVE_CONFIG_H*/
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#include <vips/intl.h>
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#include <vips/vips.h>
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/**
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* im_addgnoise:
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* @in: input image
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* @out: output image
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* @sigma: standard deviation of noise
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*
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* Add gaussian noise with mean 0 and variance sigma to @in.
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* The noise is generated by averaging 12 random numbers,
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* see page 78, PIETGEN, 1989.
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*
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* See also: im_gaussnoise().
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*
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* Returns: 0 on success, -1 on error
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*/
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int
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im_addgnoise( IMAGE *in, IMAGE *out, double sigma )
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{
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IMAGE *t;
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if( !(t = im_open_local( out, "im_addgnoise", "p" )) ||
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im_gaussnoise( t, in->Xsize, in->Ysize, 0, sigma ) ||
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im_add( in, t, out ) )
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return( -1 );
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return( 0 );
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}
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