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/* -*- c++ -*- */
/*
* Copyright 2004,2007,2008,2010,2012 Free Software Foundation, Inc.
*
* This file is part of GNU Radio
*
* GNU Radio is free software; you can redistribute it and/or modify
* it under the terms of the GNU General Public License as published by
* the Free Software Foundation; either version 3, or (at your option)
* any later version.
*
* GNU Radio 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 General Public License for more details.
*
* You should have received a copy of the GNU General Public License
* along with GNU Radio; see the file COPYING. If not, write to
* the Free Software Foundation, Inc., 51 Franklin Street,
* Boston, MA 02110-1301, USA.
*/
#ifdef HAVE_CONFIG_H
#include "config.h"
#endif
#include "fft_vcc_fftw.h"
#include <gr_io_signature.h>
#include <math.h>
#include <string.h>
namespace gr {
namespace fft {
fft_vcc::sptr fft_vcc::make(int fft_size, bool forward,
const std::vector<float> &window,
bool shift, int nthreads)
{
return gnuradio::get_initial_sptr(new fft_vcc_fftw
(fft_size, forward, window,
shift, nthreads));
}
fft_vcc_fftw::fft_vcc_fftw(int fft_size, bool forward,
const std::vector<float> &window,
bool shift, int nthreads)
: gr_sync_block("fft_vcc_fftw",
gr_make_io_signature(1, 1, fft_size * sizeof(gr_complex)),
gr_make_io_signature(1, 1, fft_size * sizeof(gr_complex))),
d_fft_size(fft_size), d_forward(forward), d_shift(shift)
{
d_fft = new fft_complex(d_fft_size, forward, nthreads);
}
fft_vcc_fftw::~fft_vcc_fftw()
{
delete d_fft;
}
void
fft_vcc_fftw::set_nthreads(int n)
{
d_fft->set_nthreads(n);
}
int
fft_vcc_fftw::nthreads() const
{
return d_fft->nthreads();
}
bool
fft_vcc_fftw::set_window(const std::vector<float> &window)
{
if(window.size()==0 || window.size()==d_fft_size) {
d_window=window;
return true;
}
else
return false;
}
int
fft_vcc_fftw::work(int noutput_items,
gr_vector_const_void_star &input_items,
gr_vector_void_star &output_items)
{
const gr_complex *in = (const gr_complex *) input_items[0];
gr_complex *out = (gr_complex *) output_items[0];
unsigned int input_data_size = input_signature()->sizeof_stream_item (0);
unsigned int output_data_size = output_signature()->sizeof_stream_item (0);
int count = 0;
while(count++ < noutput_items) {
// copy input into optimally aligned buffer
if(d_window.size()) {
gr_complex *dst = d_fft->get_inbuf();
if(!d_forward && d_shift) {
unsigned int offset = (!d_forward && d_shift)?(d_fft_size/2):0;
int fft_m_offset = d_fft_size - offset;
for(unsigned int i = 0; i < offset; i++) // apply window
dst[i+fft_m_offset] = in[i] * d_window[i];
for(unsigned int i = offset; i < d_fft_size; i++) // apply window
dst[i-offset] = in[i] * d_window[i];
}
else {
for(unsigned int i = 0; i < d_fft_size; i++) // apply window
dst[i] = in[i] * d_window[i];
}
}
else {
if(!d_forward && d_shift) { // apply an ifft shift on the data
gr_complex *dst = d_fft->get_inbuf();
unsigned int len = (unsigned int)(floor(d_fft_size/2.0)); // half length of complex array
memcpy(&dst[0], &in[len], sizeof(gr_complex)*(d_fft_size - len));
memcpy(&dst[d_fft_size - len], &in[0], sizeof(gr_complex)*len);
}
else {
memcpy(d_fft->get_inbuf(), in, input_data_size);
}
}
// compute the fft
d_fft->execute();
// copy result to our output
if(d_forward && d_shift) { // apply a fft shift on the data
unsigned int len = (unsigned int)(ceil(d_fft_size/2.0));
memcpy(&out[0], &d_fft->get_outbuf()[len], sizeof(gr_complex)*(d_fft_size - len));
memcpy(&out[d_fft_size - len], &d_fft->get_outbuf()[0], sizeof(gr_complex)*len);
}
else {
memcpy (out, d_fft->get_outbuf (), output_data_size);
}
in += d_fft_size;
out += d_fft_size;
}
return noutput_items;
}
} /* namespace fft */
} /* namespace gr */
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