libvips/libsrc/freq_filt/im_invfft.c

/* @(#) Does a inverse fft on an input image descriptor
 * @(#) using the function fft_sp.
 * @(#)  Input complex (2 floats) output complex (2 floats)
 * @(#) 
 * @(#) Usage:
 * @(#) int im_invfft(in, out)
 * @(#) IMAGE *in, *out;
 * @(#)
 *
 * Copyright: 1990, N. Dessipris.
 *
 * Author: Nicos Dessipris 
 * Written on: 12/04/1990
 * Modified on :
 * 28/6/95 JC
 *	- rewritten, based on new im_fwfft() 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
 */

/*

    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., 59 Temple Place, Suite 330, Boston, MA  02111-1307  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 <math.h>

#ifdef HAVE_FFTW
#include <fftw.h>
#endif /*HAVE_FFTW*/

#ifdef HAVE_FFTW3
#include <fftw3.h>
#endif /*HAVE_FFTW3*/

#include <vips/vips.h>
#include <vips/internal.h>

#ifdef WITH_DMALLOC
#include <dmalloc.h>
#endif /*WITH_DMALLOC*/

#ifdef HAVE_FFTW
/* Call fftw for a 1 band image.
 */
static int 
invfft1( IMAGE *dummy, IMAGE *in, IMAGE *out )
{
	fftwnd_plan plan;

	IMAGE *cmplx = im_open_local( out, "invfft1:1", "t" );

	/* Make dp complex image.
	 */
	if( !cmplx || im_pincheck( in ) || im_poutcheck( out ) )
		return( -1 );
	if( in->Coding != IM_CODING_NONE || in->Bands != 1 ) {
                im_error( "im_invfft", _( "one band uncoded only" ) );
                return( -1 );
	}
	if( im_clip2dcm( in, cmplx ) )
                return( -1 );

	/* Make the plan for the transform. Yes, they really do use nx for
	 * height and ny for width.
	 */
	if( !(plan = fftw2d_create_plan( in->Ysize, in->Xsize,
		FFTW_BACKWARD, 
		FFTW_MEASURE | FFTW_USE_WISDOM | FFTW_IN_PLACE )) ) {
                im_error( "im_invfft", _( "unable to create transform plan" ) );
		return( -1 );
	}

	fftwnd_one( plan, (fftw_complex *) cmplx->data, NULL );

	fftwnd_destroy_plan( plan );

	/* Copy to out.
	 */
        if( im_copy( cmplx, out ) )
                return( -1 );

	return( 0 );
}
#else /*!HAVE_FFTW*/
#ifdef HAVE_FFTW3
/* Complex to complex inverse transform.
 */
static int 
invfft1( IMAGE *dummy, IMAGE *in, IMAGE *out )
{
	fftw_plan plan;

	IMAGE *cmplx = im_open_local( out, "invfft1:1", "t" );

	/* We have to have a separate buffer for the planner to work on.
	 */
	double *planner_scratch = IM_ARRAY( dummy, 
		in->Xsize * in->Ysize * 2, double );

	/* Make dp complex image.
	 */
	if( !cmplx || im_pincheck( in ) || im_poutcheck( out ) )
		return( -1 );
	if( in->Coding != IM_CODING_NONE || in->Bands != 1 ) {
                im_error( "im_invfft", _( "one band uncoded only" ) );
                return( -1 );
	}
	if( im_clip2dcm( in, cmplx ) )
                return( -1 );

	/* Make the plan for the transform. Yes, they really do use nx for
	 * height and ny for width.
	 */
	if( !(plan = fftw_plan_dft_2d( in->Ysize, in->Xsize,
		(fftw_complex *) planner_scratch, 
		(fftw_complex *) planner_scratch,
		FFTW_BACKWARD, 
		0 )) ) {
                im_error( "im_invfft", _( "unable to create transform plan" ) );
		return( -1 );
	}

	fftw_execute_dft( plan, 
		(fftw_complex *) cmplx->data, (fftw_complex *) cmplx->data );

	fftw_destroy_plan( plan );

	/* Copy to out.
	 */
        if( im_copy( cmplx, out ) )
                return( -1 );

	return( 0 );
}
#else /*!HAVE_FFTW3*/
/* Fall back to VIPS's built-in fft
 */
static int 
invfft1( IMAGE *dummy, IMAGE *in, IMAGE *out )
{
	int bpx = im_ispoweroftwo( in->Xsize );
	int bpy = im_ispoweroftwo( in->Ysize );
	float *buf, *q, *p1, *p2;
	int x, y;

	/* Buffers for real and imaginary parts.
	 */
	IMAGE *real = im_open_local( dummy, "invfft1:1", "t" );
	IMAGE *imag = im_open_local( dummy, "invfft1:2", "t" );

	/* Temps.
	 */
	IMAGE *t1 = im_open_local( dummy, "invfft1:3", "p" );
	IMAGE *t2 = im_open_local( dummy, "invfft1:4", "p" );

	if( !real || !imag || !t1 )
		return( -1 );
        if( im_pincheck( in ) || im_outcheck( out ) )
                return( -1 );
        if( in->Coding != IM_CODING_NONE || 
		in->Bands != 1 || !im_iscomplex( in ) ) {
                im_error( "im_invfft", _( "one band complex uncoded only" ) );
                return( -1 );
	}
	if( !bpx || !bpy ) {
		im_error( "im_invfft", _( "sides must be power of 2" ) );
		return( -1 );
	}

	/* Make sure we have a single-precision complex input image.
	 */
	if( im_clip2cm( in, t1 ) )
		return( -1 );

	/* Extract real and imag parts. We have to complement the imaginary.
	 */
	if( im_c2real( t1, real ) )
		return( -1 );
	if( im_c2imag( t1, t2 ) || im_lintra( -1.0, t2, 0.0, imag ) )
		return( -1 );

	/* Transform!
	 */
	if( im__fft_sp( (float *) real->data, (float *) imag->data, 
		bpx - 1, bpy - 1 ) ) {
                im_error( "im_invfft", _( "fft_sp failed" ) );
                return( -1 );
	}

	/* WIO to out.
	 */
        if( im_cp_desc( out, in ) )
                return( -1 );
	out->Bbits = IM_BBITS_COMPLEX;
	out->BandFmt = IM_BANDFMT_COMPLEX;
        if( im_setupout( out ) )
                return( -1 );
	if( !(buf = (float *) IM_ARRAY( dummy, 
		IM_IMAGE_SIZEOF_LINE( out ), PEL )) )
		return( -1 );

	/* Gather together real and imag parts. 
	 */
	for( p1 = (float *) real->data, p2 = (float *) imag->data,
		y = 0; y < out->Ysize; y++ ) {
		q = buf;

		for( x = 0; x < out->Xsize; x++ ) {
			q[0] = *p1++;
			q[1] = *p2++;
			q += 2;
		}

		if( im_writeline( y, out, (PEL *) buf ) )
			return( -1 );
	}

	return( 0 );
}
#endif /*HAVE_FFTW3*/
#endif /*HAVE_FFTW*/

int 
im_invfft( IMAGE *in, IMAGE *out )
{
	IMAGE *dummy = im_open( "im_invfft:1", "p" );

	if( !dummy )
		return( -1 );
	if( im__fftproc( dummy, in, out, invfft1 ) ) {
		im_close( dummy );
		return( -1 );
	}
	im_close( dummy );

	if( out->Bands == 1 )
		out->Type = IM_TYPE_B_W;
	else
		out->Type = IM_TYPE_MULTIBAND;

	return( 0 );
}