GNU Radio Manual and C++ API Reference 3.7.14.0
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fft_filter_ccf.h
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1/* -*- c++ -*- */
2/*
3 * Copyright 2014 Free Software Foundation, Inc.
4 *
5 * This file is part of GNU Radio
6 *
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
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10 * any later version.
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14 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
15 * GNU General Public License for more details.
16 *
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18 * along with GNU Radio; see the file COPYING. If not, write to
19 * the Free Software Foundation, Inc., 51 Franklin Street,
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21 */
22
23#ifndef INCLUDED_FILTER_FFT_FILTER_CCF_H
24#define INCLUDED_FILTER_FFT_FILTER_CCF_H
25
26#include <gnuradio/filter/api.h>
28
29namespace gr {
30namespace filter {
31
32/*!
33 * \brief Fast FFT filter with gr_complex input, gr_complex output and float taps
34 * \ingroup filter_blk
35 *
36 * \details
37 * This block implements a complex decimating filter using the
38 * fast convolution method via an FFT. The decimation factor is an
39 * integer that is greater than or equal to 1.
40 *
41 * The filter takes a set of complex (or real) taps to use in the
42 * filtering operation. These taps can be defined as anything that
43 * satisfies the user's filtering needs. For standard filters such
44 * as lowpass, highpass, bandpass, etc., the filter.firdes and
45 * filter.optfir classes provide convenient generating methods.
46 *
47 * This filter is implemented by using the FFTW package to perform
48 * the required FFTs. An optional argument, nthreads, may be
49 * passed to the constructor (or set using the set_nthreads member
50 * function) to split the FFT among N number of threads. This can
51 * improve performance on very large FFTs (that is, if the number
52 * of taps used is very large) if you have enough threads/cores to
53 * support it.
54 */
56{
57public:
58 // gr::filter::fft_filter_ccf::sptr
59 typedef boost::shared_ptr<fft_filter_ccf> sptr;
60
61 /*!
62 * Build an FFT filter blocks.
63 *
64 * \param decimation >= 1
65 * \param taps complex filter taps
66 * \param nthreads number of threads for the FFT to use
67 */
68 static sptr make(int decimation, const std::vector<float>& taps, int nthreads = 1);
69
70 virtual void set_taps(const std::vector<float>& taps) = 0;
71 virtual std::vector<float> taps() const = 0;
72
73 /*!
74 * \brief Set number of threads to use.
75 */
76 virtual void set_nthreads(int n) = 0;
77
78 /*!
79 * \brief Get number of threads being used.
80 */
81 virtual int nthreads() const = 0;
82};
83
84} /* namespace filter */
85} /* namespace gr */
86
87#endif /* INCLUDED_FILTER_FFT_FILTER_CCF_H */
Fast FFT filter with gr_complex input, gr_complex output and float taps.
Definition: fft_filter_ccf.h:56
virtual std::vector< float > taps() const =0
virtual int nthreads() const =0
Get number of threads being used.
static sptr make(int decimation, const std::vector< float > &taps, int nthreads=1)
virtual void set_taps(const std::vector< float > &taps)=0
boost::shared_ptr< fft_filter_ccf > sptr
Definition: fft_filter_ccf.h:59
virtual void set_nthreads(int n)=0
Set number of threads to use.
synchronous N:1 input to output with history
Definition: sync_decimator.h:38
#define FILTER_API
Definition: gr-filter/include/gnuradio/filter/api.h:30
static const float taps[NSTEPS+1][NTAPS]
Definition: interpolator_taps.h:9
Include this header to use the message passing features.
Definition: basic_block.h:45