libvips/libvips/deprecated/im_maxpos_avg.c

307 lines
6.6 KiB
C

/* im_maxpos_avg.c
*
* Copyright: 2006, The Nottingham Trent University
* Copyright: 2006, Tom Vajzovic
*
* Author: Tom Vajzovic
*
* Written on: 2006-09-25
* 15/10/07 JC
* - changed spelling of occurrences
* - check for !occurrences before using val
* - renamed avg as sum, a bit clearer
* 2/9/09
* - gtkdoc comment
* 8/9/08
* - rewrite from im_maxpos()
* - now handles many bands, complex, faster
* 27/7/14
* - fix a race ... did not merge states if max was equal
* 26/3/15
* - avoid NaN, thanks Paul
*/
/*
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., 51 Franklin Street, Fifth Floor, Boston, MA
02110-1301 USA
*/
/*
These files are distributed with VIPS - http://www.vips.ecs.soton.ac.uk
*/
/*
#define DEBUG
*/
#ifdef HAVE_CONFIG_H
#include <config.h>
#endif /*HAVE_CONFIG_H*/
#include <glib/gi18n-lib.h>
#include <stdio.h>
#include <stdlib.h>
#include <math.h>
#include <vips/vips.h>
#include <vips/vips7compat.h>
#include <vips/internal.h>
/* A position and maximum.
*/
typedef struct _Maxposavg {
int xpos;
int ypos;
double max;
/* occurences == 0 means we found no points, or we are uninitialised.
*/
int occurences;
} Maxposavg;
/* New sequence value.
*/
static void *
maxposavg_start( IMAGE *in, void *a, void *b )
{
Maxposavg *global_maxposavg = (Maxposavg *) b;
Maxposavg *maxposavg;
if( !(maxposavg = IM_NEW( NULL, Maxposavg )) )
return( NULL );
*maxposavg = *global_maxposavg;
return( (void *) maxposavg );
}
/* Merge the sequence value back into the per-call state.
*/
static int
maxposavg_stop( void *seq, void *a, void *b )
{
Maxposavg *global_maxposavg = (Maxposavg *) b;
Maxposavg *maxposavg = (Maxposavg *) seq;
/* Merge.
*/
if( maxposavg->occurences == 0 ) {
}
else if( maxposavg->max > global_maxposavg->max )
*global_maxposavg = *maxposavg;
else if( maxposavg->max == global_maxposavg->max ) {
global_maxposavg->xpos += maxposavg->xpos;
global_maxposavg->ypos += maxposavg->ypos;
global_maxposavg->occurences += maxposavg->occurences;
}
im_free( seq );
return( 0 );
}
/* int loop.
*/
#define ILOOP( TYPE ) { \
TYPE *p = (TYPE *) in; \
TYPE m; \
\
m = max; \
\
for( x = 0; x < sz; x++ ) { \
TYPE v = p[x]; \
\
if( occurences == 0 || v > m ) { \
m = v; \
xpos = r->left + x / reg->im->Bands; \
ypos = r->top + y; \
occurences = 1; \
} \
else if( v == m ) { \
xpos += r->left + x / reg->im->Bands; \
ypos += r->top + y; \
occurences += 1; \
} \
} \
\
max = m; \
}
/* float/double loop ... avoid NaN.
*/
#define FLOOP( TYPE ) { \
TYPE *p = (TYPE *) in; \
TYPE m; \
\
m = max; \
\
for( x = 0; x < sz; x++ ) { \
TYPE v = p[x]; \
\
if( isnan( v ) ) { \
} \
else if( occurences == 0 || v > m ) { \
m = v; \
xpos = r->left + x / reg->im->Bands; \
ypos = r->top + y; \
occurences = 1; \
} \
else if( v == m ) { \
xpos += r->left + x / reg->im->Bands; \
ypos += r->top + y; \
occurences += 1; \
} \
} \
\
max = m; \
}
/* complex/dpcomplex loop ... avoid NaN.
*/
#define CLOOP( TYPE ) { \
TYPE *p = (TYPE *) in; \
\
for( x = 0; x < sz; x++ ) { \
double mod, re, im; \
\
re = p[0]; \
im = p[1]; \
p += 2; \
mod = re * re + im * im; \
\
if( isnan( mod ) ) { \
} \
else if( occurences == 0 || mod > max ) { \
max = mod; \
xpos = r->left + x / reg->im->Bands; \
ypos = r->top + y; \
occurences = 1; \
} \
else if( mod == max ) { \
xpos += r->left + x / reg->im->Bands; \
ypos += r->top + y; \
occurences += 1; \
} \
} \
}
/* Loop over region, adding to seq.
*/
static int
maxposavg_scan( REGION *reg, void *seq, void *a, void *b, gboolean *stop )
{
const Rect *r = &reg->valid;
const int sz = IM_REGION_N_ELEMENTS( reg );
Maxposavg *maxposavg = (Maxposavg *) seq;
int x, y;
double max;
int xpos, ypos, occurences;
xpos = maxposavg->xpos;
ypos = maxposavg->ypos;
max = maxposavg->max;
occurences = maxposavg->occurences;
for( y = 0; y < r->height; y++ ) {
VipsPel *in = VIPS_REGION_ADDR( reg, r->left, r->top + y );
switch( reg->im->BandFmt ) {
case IM_BANDFMT_UCHAR: ILOOP( unsigned char ); break;
case IM_BANDFMT_CHAR: ILOOP( signed char ); break;
case IM_BANDFMT_USHORT: ILOOP( unsigned short ); break;
case IM_BANDFMT_SHORT: ILOOP( signed short ); break;
case IM_BANDFMT_UINT: ILOOP( unsigned int ); break;
case IM_BANDFMT_INT: ILOOP( signed int ); break;
case IM_BANDFMT_FLOAT: FLOOP( float ); break;
case IM_BANDFMT_DOUBLE: FLOOP( double ); break;
case IM_BANDFMT_COMPLEX: CLOOP( float ); break;
case IM_BANDFMT_DPCOMPLEX: CLOOP( double ); break;
default:
g_assert( 0 );
}
}
maxposavg->xpos = xpos;
maxposavg->ypos = ypos;
maxposavg->max = max;
maxposavg->occurences = occurences;
return( 0 );
}
/**
* im_maxpos_avg:
* @im: image to scan
* @xpos: returned X position
* @ypos: returned Y position
* @out: returned value
*
* Function to find the maximum of an image. Returns coords and value at
* double precision. In the event of a draw, returns average of all
* drawing coords.
*
* See also: im_maxpos(), im_min(), im_stats().
*
* Returns: 0 on success, -1 on error
*/
int
im_maxpos_avg( IMAGE *in, double *xpos, double *ypos, double *out )
{
Maxposavg *global_maxposavg;
if( im_pincheck( in ) ||
im_check_uncoded( "im_maxpos_avg", in ) )
return( -1 );
if( !(global_maxposavg = IM_NEW( in, Maxposavg )) )
return( -1 );
global_maxposavg->occurences = 0;
if( vips_sink( in, maxposavg_start, maxposavg_scan, maxposavg_stop,
in, global_maxposavg ) )
return( -1 );
if( global_maxposavg->occurences == 0 ) {
*xpos = nan("");
*ypos = nan("");
*out = nan("");
}
else {
/* Back to modulus.
*/
if( vips_band_format_iscomplex( in->BandFmt ) )
global_maxposavg->max = sqrt( global_maxposavg->max );
if( xpos )
*xpos = (double) global_maxposavg->xpos /
global_maxposavg->occurences;
if( ypos )
*ypos = (double) global_maxposavg->ypos /
global_maxposavg->occurences;
if( out )
*out = global_maxposavg->max;
}
return( 0 );
}