3 * Copyright 2004,2007,2008 Free Software Foundation, Inc.
5 * This file is part of GNU Radio
7 * GNU Radio is free software; you can redistribute it and/or modify
8 * it under the terms of the GNU General Public License as published by
9 * the Free Software Foundation; either version 3, or (at your option)
12 * GNU Radio is distributed in the hope that it will be useful,
13 * but WITHOUT ANY WARRANTY; without even the implied warranty of
14 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
15 * GNU General Public License for more details.
17 * You should have received a copy of the GNU General Public License
18 * along with GNU Radio; see the file COPYING. If not, write to
19 * the Free Software Foundation, Inc., 51 Franklin Street,
20 * Boston, MA 02110-1301, USA.
27 #include <gr_fft_vcc_fftw.h>
28 #include <gr_io_signature.h>
34 gr_make_fft_vcc_fftw (int fft_size, bool forward, const std::vector<float> &window, bool shift)
36 return gr_fft_vcc_sptr (new gr_fft_vcc_fftw (fft_size, forward, window, shift));
39 gr_fft_vcc_fftw::gr_fft_vcc_fftw (int fft_size, bool forward,
40 const std::vector<float> &window, bool shift)
41 : gr_fft_vcc("fft_vcc_fftw", fft_size, forward, window, shift)
43 d_fft = new gri_fft_complex (d_fft_size, forward);
46 gr_fft_vcc_fftw::~gr_fft_vcc_fftw ()
52 gr_fft_vcc_fftw::work (int noutput_items,
53 gr_vector_const_void_star &input_items,
54 gr_vector_void_star &output_items)
56 const gr_complex *in = (const gr_complex *) input_items[0];
57 gr_complex *out = (gr_complex *) output_items[0];
59 unsigned int input_data_size = input_signature()->sizeof_stream_item (0);
60 unsigned int output_data_size = output_signature()->sizeof_stream_item (0);
64 while (count++ < noutput_items){
66 // copy input into optimally aligned buffer
69 gr_complex *dst = d_fft->get_inbuf();
70 for (unsigned int i = 0; i < d_fft_size; i++) // apply window
71 dst[i] = in[i] * d_window[i];
74 if(!d_forward && d_shift) { // apply an ifft shift on the data
75 gr_complex *dst = d_fft->get_inbuf();
76 unsigned int len = (unsigned int)(floor(d_fft_size/2.0)); // half length of complex array
77 memcpy(&dst[0], &in[len], sizeof(gr_complex)*(d_fft_size - len));
78 memcpy(&dst[d_fft_size - len], &in[0], sizeof(gr_complex)*len);
81 memcpy (d_fft->get_inbuf(), in, input_data_size);
88 // copy result to our output
89 if(d_forward && d_shift) { // apply a fft shift on the data
90 unsigned int len = (unsigned int)(ceil(d_fft_size/2.0));
91 memcpy(&out[0], &d_fft->get_outbuf()[len], sizeof(gr_complex)*(d_fft_size - len));
92 memcpy(&out[d_fft_size - len], &d_fft->get_outbuf()[0], sizeof(gr_complex)*len);
95 memcpy (out, d_fft->get_outbuf (), output_data_size);
102 return noutput_items;