304 lines
7.1 KiB
C
304 lines
7.1 KiB
C
/* Inverse FFT
|
|
*
|
|
* Author: Nicos Dessipris
|
|
* Written on: 12/04/1990
|
|
* Modified on :
|
|
* 28/6/95 JC
|
|
* - rewritten, based on new im_invfft() code
|
|
* 10/9/98 JC
|
|
* - frees memory more quickly
|
|
* 2/4/02 JC
|
|
* - fftw code added
|
|
* 13/7/02 JC
|
|
* - Type reset
|
|
* 27/2/03 JC
|
|
* - tiny speed-up ... save 1 copy on write
|
|
* 22/1/04 JC
|
|
* - oops, fix for segv on wider than high fftw transforms
|
|
* 3/11/04
|
|
* - added fftw3 support
|
|
* 7/2/10
|
|
* - gtkdoc
|
|
* 27/1/12
|
|
* - better setting of interpretation
|
|
* - remove own fft fallback code
|
|
* - remove fftw2 path
|
|
* - reduce memuse
|
|
* 3/1/14
|
|
* - redone 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 <stdio.h>
|
|
#include <stdlib.h>
|
|
|
|
#include <vips/vips.h>
|
|
#include <vips/internal.h>
|
|
#include "pfreqfilt.h"
|
|
|
|
#ifdef HAVE_FFTW
|
|
|
|
#include <fftw3.h>
|
|
|
|
typedef struct _VipsInvfft {
|
|
VipsFreqfilt parent_instance;
|
|
|
|
gboolean real;
|
|
|
|
} VipsInvfft;
|
|
|
|
typedef VipsFreqfiltClass VipsInvfftClass;
|
|
|
|
G_DEFINE_TYPE( VipsInvfft, vips_invfft, VIPS_TYPE_FREQFILT );
|
|
|
|
/* Complex to complex inverse transform.
|
|
*/
|
|
static int
|
|
cinvfft1( VipsObject *object, VipsImage *in, VipsImage **out )
|
|
{
|
|
VipsImage **t = (VipsImage **) vips_object_local_array( object, 4 );
|
|
VipsInvfft *invfft = (VipsInvfft *) object;
|
|
VipsObjectClass *class = VIPS_OBJECT_GET_CLASS( invfft );
|
|
|
|
fftw_plan plan;
|
|
double *planner_scratch;
|
|
|
|
if( vips_check_mono( class->nickname, in ) ||
|
|
vips_check_uncoded( class->nickname, in ) )
|
|
return( -1 );
|
|
|
|
/* Convert input to a complex double membuffer.
|
|
*/
|
|
*out = vips_image_new_memory();
|
|
if( vips_cast_dpcomplex( in, &t[0], NULL ) ||
|
|
vips_image_write( t[0], *out ) )
|
|
return( -1 );
|
|
|
|
/* Make the plan for the transform. Yes, they really do use nx for
|
|
* height and ny for width.
|
|
*/
|
|
if( !(planner_scratch = VIPS_ARRAY( invfft,
|
|
VIPS_IMAGE_N_PELS( in ) * 2, double )) )
|
|
return( -1 );
|
|
if( !(plan = fftw_plan_dft_2d( in->Ysize, in->Xsize,
|
|
(fftw_complex *) planner_scratch,
|
|
(fftw_complex *) planner_scratch,
|
|
FFTW_BACKWARD,
|
|
0 )) ) {
|
|
vips_error( class->nickname,
|
|
"%s", _( "unable to create transform plan" ) );
|
|
return( -1 );
|
|
}
|
|
|
|
fftw_execute_dft( plan,
|
|
(fftw_complex *) (*out)->data, (fftw_complex *) (*out)->data );
|
|
|
|
fftw_destroy_plan( plan );
|
|
|
|
(*out)->Type = VIPS_INTERPRETATION_B_W;
|
|
|
|
return( 0 );
|
|
}
|
|
|
|
/* Complex to real inverse transform.
|
|
*/
|
|
static int
|
|
rinvfft1( VipsObject *object, VipsImage *in, VipsImage **out )
|
|
{
|
|
VipsImage **t = (VipsImage **) vips_object_local_array( object, 4 );
|
|
VipsInvfft *invfft = (VipsInvfft *) object;
|
|
VipsObjectClass *class = VIPS_OBJECT_GET_CLASS( invfft );
|
|
const int half_width = in->Xsize / 2 + 1;
|
|
|
|
double *half_complex;
|
|
double *planner_scratch;
|
|
fftw_plan plan;
|
|
int x, y;
|
|
double *q, *p;
|
|
|
|
/* Convert input to a complex double membuffer.
|
|
*/
|
|
t[1] = vips_image_new_memory();
|
|
if( vips_cast_dpcomplex( in, &t[0], NULL ) ||
|
|
vips_image_write( t[0], t[1] ) )
|
|
return( -1 );
|
|
|
|
/* Build half-complex image.
|
|
*/
|
|
if( !(half_complex = VIPS_ARRAY( invfft,
|
|
t[1]->Ysize * half_width * 2, double )) )
|
|
return( -1 );
|
|
q = half_complex;
|
|
for( y = 0; y < t[1]->Ysize; y++ ) {
|
|
p = ((double *) t[1]->data) + (guint64) y * t[1]->Xsize * 2;
|
|
|
|
for( x = 0; x < half_width; x++ ) {
|
|
q[0] = p[0];
|
|
q[1] = p[1];
|
|
p += 2;
|
|
q += 2;
|
|
}
|
|
}
|
|
|
|
/* Make mem buffer real image for output.
|
|
*/
|
|
*out = vips_image_new_memory();
|
|
if( vips_image_pipelinev( *out, VIPS_DEMAND_STYLE_ANY, t[1], NULL ) )
|
|
return( -1 );
|
|
(*out)->BandFmt = VIPS_FORMAT_DOUBLE;
|
|
(*out)->Type = VIPS_INTERPRETATION_B_W;
|
|
if( vips_image_write_prepare( *out ) )
|
|
return( -1 );
|
|
|
|
/* Make the plan for the transform. Yes, they really do use nx for
|
|
* height and ny for width.
|
|
*/
|
|
if( !(planner_scratch = VIPS_ARRAY( invfft,
|
|
t[1]->Ysize * half_width * 2, double )) )
|
|
return( -1 );
|
|
if( !(plan = fftw_plan_dft_c2r_2d( t[1]->Ysize, t[1]->Xsize,
|
|
(fftw_complex *) planner_scratch, (double *) (*out)->data,
|
|
0 )) ) {
|
|
vips_error( class->nickname,
|
|
"%s", _( "unable to create transform plan" ) );
|
|
return( -1 );
|
|
}
|
|
|
|
fftw_execute_dft_c2r( plan,
|
|
(fftw_complex *) half_complex, (double *) (*out)->data );
|
|
|
|
fftw_destroy_plan( plan );
|
|
|
|
return( 0 );
|
|
}
|
|
|
|
static int
|
|
vips_invfft_build( VipsObject *object )
|
|
{
|
|
VipsFreqfilt *freqfilt = VIPS_FREQFILT( object );
|
|
VipsInvfft *invfft = (VipsInvfft *) object;
|
|
VipsImage **t = (VipsImage **) vips_object_local_array( object, 4 );
|
|
|
|
VipsImage *in;
|
|
|
|
if( VIPS_OBJECT_CLASS( vips_invfft_parent_class )->
|
|
build( object ) )
|
|
return( -1 );
|
|
|
|
in = freqfilt->in;
|
|
|
|
if( vips_image_decode( in, &t[0] ) )
|
|
return( -1 );
|
|
in = t[0];
|
|
|
|
if( invfft->real ) {
|
|
if( vips__fftproc( VIPS_OBJECT( invfft ),
|
|
in, &t[1], rinvfft1 ) )
|
|
return( -1 );
|
|
}
|
|
else {
|
|
if( vips__fftproc( VIPS_OBJECT( invfft ),
|
|
in, &t[1], cinvfft1 ) )
|
|
return( -1 );
|
|
}
|
|
|
|
if( vips_image_write( t[1], freqfilt->out ) )
|
|
return( -1 );
|
|
|
|
return( 0 );
|
|
}
|
|
|
|
static void
|
|
vips_invfft_class_init( VipsInvfftClass *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 = "invfft";
|
|
vobject_class->description = _( "inverse FFT" );
|
|
vobject_class->build = vips_invfft_build;
|
|
|
|
VIPS_ARG_BOOL( class, "real", 4,
|
|
_( "Real" ),
|
|
_( "Output only the real part of the transform" ),
|
|
VIPS_ARGUMENT_OPTIONAL_INPUT,
|
|
G_STRUCT_OFFSET( VipsInvfft, real ),
|
|
FALSE );
|
|
|
|
}
|
|
|
|
static void
|
|
vips_invfft_init( VipsInvfft *invfft )
|
|
{
|
|
}
|
|
|
|
#endif /*HAVE_FFTW*/
|
|
|
|
/**
|
|
* vips_invfft: (method)
|
|
* @in: input image
|
|
* @out: (out): output image
|
|
* @...: %NULL-terminated list of optional named arguments
|
|
*
|
|
* Optional arguments:
|
|
*
|
|
* * @real: only output the real part
|
|
*
|
|
* Transform an image from Fourier space to real space. The result is complex.
|
|
* If you are OK with a real result, set @real, it's quicker.
|
|
*
|
|
* VIPS uses the fftw Fourier Transform library. If this library was not
|
|
* available when VIPS was configured, these functions will fail.
|
|
*
|
|
* See also: vips_fwfft().
|
|
*
|
|
* Returns: 0 on success, -1 on error.
|
|
*/
|
|
int
|
|
vips_invfft( VipsImage *in, VipsImage **out, ... )
|
|
{
|
|
va_list ap;
|
|
int result;
|
|
|
|
va_start( ap, out );
|
|
result = vips_call_split( "invfft", ap, in, out );
|
|
va_end( ap );
|
|
|
|
return( result );
|
|
}
|
|
|