libvips/libvips/freqfilt/freqfilt.c
2014-11-17 10:32:40 +00:00

181 lines
4.5 KiB
C

/* base class for all Fourier stuff
*
* properties:
* - single output image
*/
/*
Copyright (C) 1991-2005 The National Gallery
This library 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 2.1 of the License, or (at your option) any later version.
This library 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 library; 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 <vips/intl.h>
#include <stdio.h>
#include <stdlib.h>
#include <math.h>
#include <vips/vips.h>
#include <vips/internal.h>
#include "pfreqfilt.h"
/**
* SECTION: freqfilt
* @short_description: fourier transforms and frequency-domin filters
* @stability: Stable
* @see_also: <link linkend="VipsImage">image</link>
* @include: vips/vips.h
*
* To and from Fourier space, filter in Fourier space, convert Fourier-space
* images to a displayable form.
*/
G_DEFINE_ABSTRACT_TYPE( VipsFreqfilt, vips_freqfilt, VIPS_TYPE_OPERATION );
static int
vips_freqfilt_build( VipsObject *object )
{
VipsFreqfilt *freqfilt = VIPS_FREQFILT( object );
#ifdef DEBUG
printf( "vips_freqfilt_build: " );
vips_object_print_name( object );
printf( "\n" );
#endif /*DEBUG*/
g_object_set( freqfilt, "out", vips_image_new(), NULL );
if( VIPS_OBJECT_CLASS( vips_freqfilt_parent_class )->build( object ) )
return( -1 );
return( 0 );
}
static void
vips_freqfilt_class_init( VipsFreqfiltClass *class )
{
GObjectClass *gobject_class = G_OBJECT_CLASS( class );
VipsObjectClass *vobject_class = VIPS_OBJECT_CLASS( class );
gobject_class->set_property = vips_object_set_property;
gobject_class->get_property = vips_object_get_property;
vobject_class->nickname = "freqfilt";
vobject_class->description = _( "frequency-domain filter operations" );
vobject_class->build = vips_freqfilt_build;
VIPS_ARG_IMAGE( class, "in", -1,
_( "in" ),
_( "Input image" ),
VIPS_ARGUMENT_REQUIRED_INPUT,
G_STRUCT_OFFSET( VipsFreqfilt, in ) );
VIPS_ARG_IMAGE( class, "out", 1,
_( "Output" ),
_( "Output image" ),
VIPS_ARGUMENT_REQUIRED_OUTPUT,
G_STRUCT_OFFSET( VipsFreqfilt, out ) );
}
static void
vips_freqfilt_init( VipsFreqfilt *freqfilt )
{
}
/* Transform an n-band image with a 1-band processing function.
*
* Memory strategy: we need memory buffers for the input and the output of
* fftw. In some modes fftw generates only half the output and we construct
* the rest.
*
* input pipeline ->
* bandsplit ->
* full memory image, freed when im_*fft*() exits ->
* fftw ->
* half memory image, freed when im_*fft*() exits ->
* full memory image, freed when @out is freed ->
* partial bandjoin ->
* output pipeline
*
* im__fftproc() needs to just call im__fftproc_fn directly for 1 band images,
* so we can't cache the output in this fn.
*/
int
vips__fftproc( VipsObject *context,
VipsImage *in, VipsImage **out, VipsFftProcessFn fn )
{
VipsImage **bands = (VipsImage **)
vips_object_local_array( context, in->Bands );
VipsImage **fft = (VipsImage **)
vips_object_local_array( context, in->Bands );
int b;
if( in->Bands == 1 )
return( fn( context, in, out ) );
for( b = 0; b < in->Bands; b++ )
if( vips_extract_band( in, &bands[b], b, NULL ) ||
fn( context, bands[b], &fft[b] ) )
return( -1 );
if( vips_bandjoin( fft, out, in->Bands, NULL ) )
return( -1 );
return( 0 );
}
/* Called from iofuncs to init all operations in this dir. Use a plugin system
* instead?
*/
void
vips_freqfilt_operation_init( void )
{
#ifdef HAVE_FFTW
extern GType vips_fwfft_get_type( void );
extern GType vips_invfft_get_type( void );
#endif /*HAVE_FFTW*/
extern GType vips_freqmult_get_type( void );
extern GType vips_spectrum_get_type( void );
extern GType vips_phasecor_get_type( void );
#ifdef HAVE_FFTW
vips_fwfft_get_type();
vips_invfft_get_type();
#endif /*HAVE_FFTW*/
vips_freqmult_get_type();
vips_spectrum_get_type();
vips_phasecor_get_type();
}