| /* find percent of pixels |
| * 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 |
| * 25/3/10 |
| * - gtkdoc |
| */ |
| |
| /* |
| |
| 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*/ |
| |
| /** |
| * im_mpercent_hist: |
| * @hist: input histogram image |
| * @percent: threshold percentage |
| * @out: output threshold value |
| * |
| * Just like im_mpercent(), except it works on an image histogram. Handy if |
| * you want to run im_mpercent() several times without having to recompute the |
| * histogram each time. |
| * |
| * See also: im_mpercent(). |
| * |
| * Returns: 0 on success, -1 on error |
| */ |
| int |
| im_mpercent_hist( IMAGE *hist, double percent, int *out ) |
| { |
| IMAGE *base; |
| IMAGE *t[6]; |
| double pos; |
| |
| if( im_check_hist( "im_mpercent", hist ) ) |
| return( -1 ); |
| |
| if( !(base = im_open( "im_mpercent", "p" )) ) |
| return( -1 ); |
| if( im_open_local_array( base, t, 6, "im_mpercent", "p" ) ) { |
| im_close( base ); |
| return( -1 ); |
| } |
| |
| if( im_histcum( hist, 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 ); |
| } |
| |
| /** |
| * im_mpercent: |
| * @in: input image |
| * @percent: threshold percentage |
| * @out: output threshold value |
| * |
| * im_mpercent() returns (through the @out parameter) the threshold above |
| * which there are @percent values of @in. If for example percent=.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. |
| * |
| * The function works for uchar and ushort images only. It can be used |
| * to threshold the scaled result of a filtering operation. |
| * |
| * See also: im_histgr(), im_profile(). |
| * |
| * Returns: 0 on success, -1 on error |
| */ |
| int |
| im_mpercent( IMAGE *in, double percent, int *out ) |
| { |
| IMAGE *t; |
| |
| if( !(t = im_open( "im_mpercent1", "p" )) ) |
| return( -1 ); |
| if( im_histgr( in, t, -1 ) || |
| im_mpercent_hist( t, percent, out ) ) { |
| im_close( t ); |
| return( -1 ); |
| } |
| im_close( t ); |
| |
| return( 0 ); |
| } |
