102 lines
2.6 KiB
C
102 lines
2.6 KiB
C
/* @(#) Function which returns an int. This integer is the threshold
|
|
* @(#) above which there are percent values of the input images
|
|
* @(#) If for instance precent=.1, the number of pels of the input image
|
|
* @(#) with values greater than the returned int will correspond to
|
|
* @(#) 10% of all pels of the image.
|
|
* @(#) One band IM_BANDFMT_UCHAR images only.
|
|
* @(#)
|
|
* @(#) Function im_mpercent() assumes that input
|
|
* @(#) is either memory mapped or in a buffer.
|
|
* @(#)
|
|
* @(#) int im_percent(in, percent)
|
|
* @(#) IMAGE *in;
|
|
* @(#) double percent;
|
|
* @(#)
|
|
* @(#) Returns 0 on success and -1 on error
|
|
*
|
|
* Copyright: 1990, N. Dessipris
|
|
*
|
|
* Author: N. Dessipris
|
|
* Written on: 02/08/1990
|
|
* Modified on : 29/4/93 K.Martinez for Sys5
|
|
* 20/2/95 JC
|
|
* - now returns result through parameter
|
|
* - ANSIfied a little
|
|
* 19/1/07
|
|
* - redone with the vips hist operators
|
|
*/
|
|
|
|
/*
|
|
|
|
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 <string.h>
|
|
|
|
#include <vips/vips.h>
|
|
|
|
#ifdef WITH_DMALLOC
|
|
#include <dmalloc.h>
|
|
#endif /*WITH_DMALLOC*/
|
|
|
|
/* What threshold will select a specified percentage of the pixels in the
|
|
* image.
|
|
*/
|
|
int
|
|
im_mpercent( IMAGE *in, double percent, int *out )
|
|
{
|
|
IMAGE *base;
|
|
IMAGE *t[6];
|
|
double pos;
|
|
|
|
if( !(base = im_open( "im_mpercent1", "p" )) )
|
|
return( -1 );
|
|
if( im_open_local_array( base, t, 6, "im_mpercent", "p" ) ) {
|
|
im_close( base );
|
|
return( -1 );
|
|
}
|
|
|
|
if( im_histgr( in, t[0], -1 ) ||
|
|
im_histcum( t[0], t[1] ) ||
|
|
im_histnorm( t[1], t[2] ) ||
|
|
im_lessconst( t[2], t[3], percent * t[2]->Xsize ) ||
|
|
im_fliphor( t[3], t[4] ) ||
|
|
im_profile( t[4], t[5], 1 ) ||
|
|
im_avg( t[5], &pos ) ) {
|
|
im_close( base );
|
|
return( -1 );
|
|
}
|
|
im_close( base );
|
|
|
|
*out = pos;
|
|
|
|
return( 0 );
|
|
}
|