235 lines
6.1 KiB
C
235 lines
6.1 KiB
C
/* convolution
|
|
*
|
|
* 12/8/13
|
|
* - from vips_hist_cum()
|
|
* 8/5/17
|
|
* - default to float ... int will often lose precision and should not be
|
|
* the default
|
|
*/
|
|
|
|
/*
|
|
|
|
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 <glib/gi18n-lib.h>
|
|
|
|
#include <stdio.h>
|
|
|
|
#include <vips/vips.h>
|
|
#include <vips/internal.h>
|
|
|
|
#include "pconvolution.h"
|
|
|
|
typedef struct {
|
|
VipsConvolution parent_instance;
|
|
|
|
VipsPrecision precision;
|
|
int layers;
|
|
int cluster;
|
|
} VipsConv;
|
|
|
|
typedef VipsConvolutionClass VipsConvClass;
|
|
|
|
G_DEFINE_TYPE( VipsConv, vips_conv, VIPS_TYPE_CONVOLUTION );
|
|
|
|
static int
|
|
vips_conv_build( VipsObject *object )
|
|
{
|
|
VipsConvolution *convolution = (VipsConvolution *) object;
|
|
VipsConv *conv = (VipsConv *) object;
|
|
VipsImage **t = (VipsImage **) vips_object_local_array( object, 4 );
|
|
|
|
VipsImage *in;
|
|
|
|
if( VIPS_OBJECT_CLASS( vips_conv_parent_class )->build( object ) )
|
|
return( -1 );
|
|
|
|
g_object_set( conv, "out", vips_image_new(), NULL );
|
|
|
|
in = convolution->in;
|
|
|
|
/*
|
|
printf( "vips_conv_build: convolving with:\n" );
|
|
vips_matrixprint( convolution->M, NULL );
|
|
*/
|
|
|
|
/* Unpack for processing.
|
|
*/
|
|
if( vips_image_decode( in, &t[0] ) )
|
|
return( -1 );
|
|
in = t[0];
|
|
|
|
switch( conv->precision ) {
|
|
case VIPS_PRECISION_FLOAT:
|
|
if( vips_convf( in, &t[1], convolution->M, NULL ) ||
|
|
vips_image_write( t[1], convolution->out ) )
|
|
return( -1 );
|
|
break;
|
|
|
|
case VIPS_PRECISION_INTEGER:
|
|
if( vips_convi( in, &t[1], convolution->M, NULL ) ||
|
|
vips_image_write( t[1], convolution->out ) )
|
|
return( -1 );
|
|
break;
|
|
|
|
case VIPS_PRECISION_APPROXIMATE:
|
|
if( vips_conva( in, &t[1], convolution->M,
|
|
"layers", conv->layers,
|
|
"cluster", conv->cluster,
|
|
NULL ) ||
|
|
vips_image_write( t[1], convolution->out ) )
|
|
return( -1 );
|
|
break;
|
|
|
|
default:
|
|
g_assert_not_reached();
|
|
}
|
|
|
|
vips_reorder_margin_hint( convolution->out,
|
|
convolution->M->Xsize * convolution->M->Ysize );
|
|
|
|
return( 0 );
|
|
}
|
|
|
|
static void
|
|
vips_conv_class_init( VipsConvClass *class )
|
|
{
|
|
GObjectClass *gobject_class = G_OBJECT_CLASS( class );
|
|
VipsObjectClass *object_class = (VipsObjectClass *) class;
|
|
|
|
gobject_class->set_property = vips_object_set_property;
|
|
gobject_class->get_property = vips_object_get_property;
|
|
|
|
object_class->nickname = "conv";
|
|
object_class->description = _( "convolution operation" );
|
|
object_class->build = vips_conv_build;
|
|
|
|
VIPS_ARG_ENUM( class, "precision", 103,
|
|
_( "Precision" ),
|
|
_( "Convolve with this precision" ),
|
|
VIPS_ARGUMENT_OPTIONAL_INPUT,
|
|
G_STRUCT_OFFSET( VipsConv, precision ),
|
|
VIPS_TYPE_PRECISION, VIPS_PRECISION_FLOAT );
|
|
|
|
VIPS_ARG_INT( class, "layers", 104,
|
|
_( "Layers" ),
|
|
_( "Use this many layers in approximation" ),
|
|
VIPS_ARGUMENT_OPTIONAL_INPUT,
|
|
G_STRUCT_OFFSET( VipsConv, layers ),
|
|
1, 1000, 5 );
|
|
|
|
VIPS_ARG_INT( class, "cluster", 105,
|
|
_( "Cluster" ),
|
|
_( "Cluster lines closer than this in approximation" ),
|
|
VIPS_ARGUMENT_OPTIONAL_INPUT,
|
|
G_STRUCT_OFFSET( VipsConv, cluster ),
|
|
1, 100, 1 );
|
|
|
|
}
|
|
|
|
static void
|
|
vips_conv_init( VipsConv *conv )
|
|
{
|
|
conv->precision = VIPS_PRECISION_FLOAT;
|
|
conv->layers = 5;
|
|
conv->cluster = 1;
|
|
}
|
|
|
|
/**
|
|
* vips_conv: (method)
|
|
* @in: input image
|
|
* @out: (out): output image
|
|
* @mask: convolve with this mask
|
|
* @...: %NULL-terminated list of optional named arguments
|
|
*
|
|
* Optional arguments:
|
|
*
|
|
* * @precision: #VipsPrecision, calculation accuracy
|
|
* * @layers: %gint, number of layers for approximation
|
|
* * @cluster: %gint, cluster lines closer than this distance
|
|
*
|
|
* Convolution.
|
|
*
|
|
* Perform a convolution of @in with @mask.
|
|
* Each output pixel is calculated as:
|
|
*
|
|
* |[
|
|
* sigma[i]{pixel[i] * mask[i]} / scale + offset
|
|
* ]|
|
|
*
|
|
* where scale and offset are part of @mask.
|
|
*
|
|
* By default, @precision is
|
|
* #VIPS_PRECISION_FLOAT. The output image
|
|
* is always #VIPS_FORMAT_FLOAT unless @in is #VIPS_FORMAT_DOUBLE, in which case
|
|
* @out is also #VIPS_FORMAT_DOUBLE.
|
|
*
|
|
* If @precision is #VIPS_PRECISION_INTEGER, then
|
|
* elements of @mask are converted to
|
|
* integers before convolution, using rint(),
|
|
* and the output image
|
|
* always has the same #VipsBandFormat as the input image.
|
|
*
|
|
* For #VIPS_FORMAT_UCHAR images and #VIPS_PRECISION_INTEGER @precision,
|
|
* vips_conv() uses a fast vector path based on
|
|
* fixed-point arithmetic. This can produce slightly different results.
|
|
* Disable the vector path with `--vips-novector` or `VIPS_NOVECTOR` or
|
|
* vips_vector_set_enabled().
|
|
*
|
|
* If @precision is #VIPS_PRECISION_APPROXIMATE then, like
|
|
* #VIPS_PRECISION_INTEGER, @mask is converted to int before convolution, and
|
|
* the output image
|
|
* always has the same #VipsBandFormat as the input image.
|
|
*
|
|
* Larger values for @layers give more accurate
|
|
* results, but are slower. As @layers approaches the mask radius, the
|
|
* accuracy will become close to exact convolution and the speed will drop to
|
|
* match. For many large masks, such as Gaussian, @n_layers need be only 10% of
|
|
* this value and accuracy will still be good.
|
|
*
|
|
* Smaller values of @cluster will give more accurate results, but be slower
|
|
* and use more memory. 10% of the mask radius is a good rule of thumb.
|
|
*
|
|
* See also: vips_convsep().
|
|
*
|
|
* Returns: 0 on success, -1 on error
|
|
*/
|
|
int
|
|
vips_conv( VipsImage *in, VipsImage **out, VipsImage *mask, ... )
|
|
{
|
|
va_list ap;
|
|
int result;
|
|
|
|
va_start( ap, mask );
|
|
result = vips_call_split( "conv", ap, in, out, mask );
|
|
va_end( ap );
|
|
|
|
return( result );
|
|
}
|