libvips/libvips/arithmetic/hist_find.c

450 lines
9.8 KiB
C

/* find histograms
*
* Copyright: 1990, 1991, N. Dessipris.
*
* Author: Nicos Dessipris.
* Written on: 09/07/1990
* Modified on : 11/03/1991
* 19/7/93 JC
* - test for Coding type added
* 26/10/94 JC
* - rewritten for ANSI
* - now does USHORT too
* - 5 x faster!
* 2/6/95 JC
* - rewritten for partials
* 3/3/01 JC
* - tiny speed ups
* 21/1/07
* - number bands from zero
* 24/3/10
* - gtkdoc
* - small cleanups
* 25/1/12
* - cast @in to u8/u16.
* 12/8/13
* - redo as a class
*/
/*
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
*/
#ifdef HAVE_CONFIG_H
#include <config.h>
#endif /*HAVE_CONFIG_H*/
#include <vips/intl.h>
#include <string.h>
#include <vips/vips.h>
#include "statistic.h"
/* Accumulate a histogram in one of these.
*/
typedef struct {
int bands; /* Number of bands in output */
int which; /* If one band in out, which band of input */
int size; /* Number of bins for each band */
int mx; /* Maximum value we have seen */
unsigned int **bins; /* All the bins! */
} Histogram;
typedef struct _VipsHistFind {
VipsStatistic parent_instance;
/* -1 for all bands, or the band we scan.
*/
int which;
/* Main image histogram. Subhists accumulate to this.
*/
Histogram *hist;
/* Write hist to this output image.
*/
VipsImage *out;
} VipsHistFind;
typedef VipsStatisticClass VipsHistFindClass;
G_DEFINE_TYPE( VipsHistFind, vips_hist_find, VIPS_TYPE_STATISTIC );
/* Build a Histogram.
*/
static Histogram *
histogram_new( VipsHistFind *hist_find, int bands, int which, int size )
{
Histogram *hist;
int i;
if( !(hist = VIPS_NEW( hist_find, Histogram )) ||
!(hist->bins = VIPS_ARRAY( hist_find, bands, unsigned int * )) )
return( NULL );
for( i = 0; i < bands; i++ ) {
if( !(hist->bins[i] =
VIPS_ARRAY( hist_find, size, unsigned int )) )
return( NULL );
memset( hist->bins[i], 0, size * sizeof( unsigned int ) );
}
hist->bands = bands;
hist->which = which;
hist->size = size;
hist->mx = 0;
return( hist );
}
static int
vips_hist_find_build( VipsObject *object )
{
VipsObjectClass *class = VIPS_OBJECT_GET_CLASS( object );
VipsStatistic *statistic = VIPS_STATISTIC( object );
VipsHistFind *hist_find = (VipsHistFind *) object;
unsigned int *obuffer;
unsigned int *q;
int i, j;
g_object_set( object,
"out", vips_image_new(),
NULL );
if( statistic->in &&
vips_check_bandno( class->nickname,
statistic->in, hist_find->which ) )
return( -1 );
/* main hist made on first thread start.
*/
if( VIPS_OBJECT_CLASS( vips_hist_find_parent_class )->build( object ) )
return( -1 );
/* Make the output image.
*/
if( vips_image_copy_fields( hist_find->out, statistic->ready ) )
return( -1 );
vips_image_init_fields( hist_find->out,
hist_find->hist->mx + 1, 1, hist_find->hist->bands,
VIPS_FORMAT_UINT,
VIPS_CODING_NONE, VIPS_INTERPRETATION_HISTOGRAM, 1.0, 1.0 );
/* Interleave for output.
*/
if( !(obuffer = VIPS_ARRAY( object,
VIPS_IMAGE_N_ELEMENTS( hist_find->out ), unsigned int )) )
return( -1 );
for( q = obuffer, j = 0; j < hist_find->out->Xsize; j++ )
for( i = 0; i < hist_find->out->Bands; i++ )
*q++ = hist_find->hist->bins[i][j];
if( vips_image_write_line( hist_find->out, 0, (VipsPel *) obuffer ) )
return( -1 );
return( 0 );
}
/* Build a sub-hist, based on the main hist.
*/
static void *
vips_hist_find_start( VipsStatistic *statistic )
{
VipsHistFind *hist_find = (VipsHistFind *) statistic;
/* Make the main hist, if necessary.
*/
if( !hist_find->hist )
hist_find->hist = histogram_new( hist_find,
hist_find->which == -1 ?
statistic->ready->Bands : 1,
hist_find->which,
statistic->ready->BandFmt == VIPS_FORMAT_UCHAR ?
256 : 65536 );
return( (void *) histogram_new( hist_find,
hist_find->hist->bands,
hist_find->hist->which,
hist_find->hist->size ) );
}
/* Join a sub-hist onto the main hist.
*/
static int
vips_hist_find_stop( VipsStatistic *statistic, void *seq )
{
Histogram *sub_hist = (Histogram *) seq;
VipsHistFind *hist_find = (VipsHistFind *) statistic;
Histogram *hist = hist_find->hist;
int i, j;
g_assert( sub_hist->bands == hist->bands &&
sub_hist->size == hist->size );
/* Add on sub-data.
*/
hist->mx = VIPS_MAX( hist->mx, sub_hist->mx );
for( i = 0; i < hist->bands; i++ )
for( j = 0; j < hist->size; j++ )
hist->bins[i][j] += sub_hist->bins[i][j];
/* Blank out sub-hist to make sure we can't add it again.
*/
sub_hist->mx = 0;
for( i = 0; i < sub_hist->bands; i++ )
sub_hist->bins[i] = NULL;
return( 0 );
}
/* Hist of all bands of uchar.
*/
static int
vips_hist_find_uchar_scan( VipsStatistic *statistic,
void *seq, int x, int y, void *in, int n )
{
Histogram *hist = (Histogram *) seq;
int nb = statistic->ready->Bands;
VipsPel *p = (VipsPel *) in;
int i, j, z;
/* Tried swapping these loops, no meaningful speedup.
*/
for( i = 0, j = 0; j < n; j++ )
for( z = 0; z < nb; z++, i++ )
hist->bins[z][p[i]] += 1;
/* Note the maximum.
*/
hist->mx = 255;
return( 0 );
}
/* Histogram of a selected band of a uchar image.
*/
static int
vips_hist_find_uchar_extract_scan( VipsStatistic *statistic,
void *seq, int x, int y, void *in, int n )
{
Histogram *hist = (Histogram *) seq;
int nb = statistic->ready->Bands;
int max = n * nb;
unsigned int *bins = hist->bins[0];
VipsPel *p = (VipsPel *) in;
int i;
for( i = hist->which; i < max; i += nb )
bins[p[i]] += 1;
/* Note the maximum.
*/
hist->mx = 255;
return( 0 );
}
/* Histogram of all bands of a ushort image.
*/
static int
vips_hist_find_ushort_scan( VipsStatistic *statistic,
void *seq, int x, int y, void *in, int n )
{
Histogram *hist = (Histogram *) seq;
int mx = hist->mx;
int nb = statistic->ready->Bands;
unsigned short *p = (unsigned short *) in;
int i, j, z;
for( i = 0, j = 0; j < n; j++ )
for( z = 0; z < nb; z++, i++ ) {
int v = p[i];
/* Adjust maximum.
*/
if( v > mx )
mx = v;
hist->bins[z][v] += 1;
}
/* Note the maximum.
*/
hist->mx = mx;
return( 0 );
}
/* Histogram of one band of a ushort image.
*/
static int
vips_hist_find_ushort_extract_scan( VipsStatistic *statistic,
void *seq, int x, int y, void *in, int n )
{
Histogram *hist = (Histogram *) seq;
int mx = hist->mx;
unsigned int *bins = hist->bins[0];
unsigned short *p = (unsigned short *) in;
int nb = statistic->ready->Bands;
int max = nb * n;
int i;
for( i = hist->which; i < max; i += nb ) {
int v = p[i];
/* Adjust maximum.
*/
if( v > mx )
mx = v;
bins[v] += 1;
}
/* Note the maximum.
*/
hist->mx = mx;
return( 0 );
}
static int
vips_hist_find_scan( VipsStatistic *statistic, void *seq,
int x, int y, void *in, int n )
{
VipsHistFind *hist_find = (VipsHistFind *) statistic;
VipsStatisticScanFn scan;
if( hist_find->which < 0 ) {
if( statistic->in->BandFmt == VIPS_FORMAT_UCHAR )
scan = vips_hist_find_uchar_scan;
else
scan = vips_hist_find_ushort_scan;
}
else {
if( statistic->in->BandFmt == VIPS_FORMAT_UCHAR )
scan = vips_hist_find_uchar_extract_scan;
else
scan = vips_hist_find_ushort_extract_scan;
}
return( scan( statistic, seq, x, y, in, n ) );
}
/* Save a bit of typing.
*/
#define UC VIPS_FORMAT_UCHAR
#define US VIPS_FORMAT_USHORT
#define UI VIPS_FORMAT_UINT
/* Type mapping: go to uchar or ushort.
*/
static const VipsBandFormat bandfmt_histgr[10] = {
/* UC C US S UI I F X D DX */
UC, UC, US, US, US, US, US, US, US, US
};
static void
vips_hist_find_class_init( VipsHistFindClass *class )
{
GObjectClass *gobject_class = (GObjectClass *) class;
VipsObjectClass *object_class = (VipsObjectClass *) class;
VipsStatisticClass *sclass = VIPS_STATISTIC_CLASS( class );
gobject_class->set_property = vips_object_set_property;
gobject_class->get_property = vips_object_get_property;
object_class->nickname = "hist_find";
object_class->description = _( "find image histogram" );
object_class->build = vips_hist_find_build;
sclass->start = vips_hist_find_start;
sclass->scan = vips_hist_find_scan;
sclass->stop = vips_hist_find_stop;
sclass->format_table = bandfmt_histgr;
VIPS_ARG_IMAGE( class, "out", 100,
_( "Output" ),
_( "Output histogram" ),
VIPS_ARGUMENT_REQUIRED_OUTPUT,
G_STRUCT_OFFSET( VipsHistFind, out ) );
VIPS_ARG_INT( class, "band", 110,
_( "Band" ),
_( "Find histogram of band" ),
VIPS_ARGUMENT_OPTIONAL_INPUT,
G_STRUCT_OFFSET( VipsHistFind, which ),
-1, 100000, -1 );
}
static void
vips_hist_find_init( VipsHistFind *hist_find )
{
hist_find->which = -1;
}
/**
* vips_hist_find:
* @in: input image
* @out: output image
*
* Optional arguments:
*
* @band: band to equalise
*
* Find the histogram of @in. Find the histogram for band @band (producing a
* one-band histogram), or for all bands (producing an n-band histogram) if
* @band is -1.
*
* @in is cast to u8 or u16. @out is always u32.
*
* See also: vips_hist_find_indexed().
*
* Returns: 0 on success, -1 on error
*/
int
vips_hist_find( VipsImage *in, VipsImage **out, ... )
{
va_list ap;
int result;
va_start( ap, out );
result = vips_call_split( "hist_find", ap, in, out );
va_end( ap );
return( result );
}