libvips/libsrc/other/im_eye.c

135 lines
3.3 KiB
C

/* @(#) test pattern with increasing spatial frequence in X and amplitude in Y
* @(#) factor should be between 0 and 1 and determines the spatial frequencies
* @(#) Creates an one band float image
* @(#) Image has values between +ysize*ysize and -ysize*ysize
* @(#)
* @(#) int im_eye(image, xsize, ysize, factor)
* @(#) IMAGE *image;
* @(#) int xsize, ysize;
* @(#) double factor;
* @(#)
* @(#) Returns -1 on error and 0 on success
*
* Copyright: 1990, 1991, N.Dessipris.
*
* Author N. Dessipris
* Written on 30/05/1990
* Updated on: 27/01/1991, 07/03/1991,
* 22/7/93 JC
* - im_outcheck() added
* 30/8/95 JC
* - modernized
*/
/*
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 <stdlib.h>
#include <math.h>
#include <vips/vips.h>
#ifdef WITH_DMALLOC
#include <dmalloc.h>
#endif /*WITH_DMALLOC*/
int
im_feye( IMAGE *image, const int xsize, const int ysize, const double factor )
{
int x, y;
double constant;
double *lut;
float *line;
/* Check input args
*/
if( im_outcheck( image ) )
return( -1 );
if( factor > 1.0 || factor <= 0.0 ) {
im_errormsg( "im_feye: factor should be in [1,0)" );
return( -1 );
}
/* Set image descriptor
*/
im_initdesc( image, xsize, ysize, 1, IM_BBITS_FLOAT, IM_BANDFMT_FLOAT,
IM_CODING_NONE, IM_TYPE_B_W, 1.0, 1.0, 0, 0 );
if( im_setupout( image ) )
return( -1 );
/* Allocate space for line buffer.
*/
if( !(line = IM_ARRAY( image, xsize, float )) )
return( -1 );
/* Make a lut for easy calculations.
*/
if( !(lut = IM_ARRAY( image, image->Xsize, double )) )
return( -1 );
constant = factor * IM_PI/(2*(xsize - 1));
for( x = 0; x < image->Xsize; x++ )
lut[x] = cos( constant*x*x ) / ((ysize - 1)*(ysize - 1));
/* Make image.
*/
for( y = 0; y < image->Ysize; y++ ) {
for( x = 0; x < image->Xsize; x++ )
line[x] = y*y*lut[x];
if( im_writeline( y, image, (PEL *) line ) )
return( -1 );
}
return( 0 );
}
/* As above, but make a IM_BANDFMT_UCHAR image.
*/
int
im_eye( IMAGE *image, const int xsize, const int ysize, const double factor )
{
IMAGE *t1 = im_open_local( image, "im_eye:1", "p" );
IMAGE *t2 = im_open_local( image, "im_eye:2", "p" );
if( !t1 )
return( -1 );
/* Change range to [0,255].
*/
if( im_feye( t1, xsize, ysize, factor ) ||
im_lintra( 127.5, t1, 127.5, t2 ) ||
im_clip( t2, image ) )
return( -1 );
return( 0 );
}