libvips/libsrc/freq_filt/im_fractsurf.c
2007-08-29 16:23:50 +00:00

88 lines
2.2 KiB
C

/* @(#) Creates a vasari fractal surface of a given dimension by
* @(#) filtering white gaussian noise (function im_gaussnoise(3X))
* @(#) using the function im_fltimage_freq(3X)
* @(#)
* @(#) Usage:
* @(#) int im_fractsurf(im, frd, size)
* @(#) double frd;
* @(#) int size;
* @(#)
* @(#) Returns 0 on sucess and -1 on error
* @(#)
*
* Copyright: 1991, N. Dessipris.
*
* Author: N. Dessipris
* Written on: 10/09/1991
* Modified on:
* 20/9/95 JC
* - modernised, a little
*/
/*
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 <stdarg.h>
#include <math.h>
#include <vips/vips.h>
#include <vips/fmask.h> /* for MASK_FRACTAL_FLT */
#ifdef WITH_DMALLOC
#include <dmalloc.h>
#endif /*WITH_DMALLOC*/
int
im_fractsurf( IMAGE *out, int size, double frd )
{
IMAGE *noise = im_open_local( out, "noise.v", "p" );
if( !noise )
return( -1 );
if( frd <= 2.0 || frd >= 3.0 ) {
im_errormsg( "im_fractsurf: dimension shuld be in (2,3)" );
return( -1 );
}
if( im_gaussnoise( noise, size, size, 0.0, 1.0 ) )
return( -1 );
/* create the fractal filter mask, and perform filtering on noise
* Note that the result is in im, stored as float since
* the original noise is in float. It needs scaling for display
*/
if( im_flt_image_freq( noise, out, MASK_FRACTAL_FLT, frd ) )
return( -1 );
return( 0 );
}