GNU Radio Manual and C++ API Reference  3.10.9.1
The Free & Open Software Radio Ecosystem
fft.h
Go to the documentation of this file.
1 /* -*- c++ -*- */
2 /*
3  * Copyright 2003,2008,2012,2020 Free Software Foundation, Inc.
4  *
5  * This file is part of GNU Radio
6  *
7  * SPDX-License-Identifier: GPL-3.0-or-later
8  *
9  */
10 
11 #ifndef _FFT_FFT_H_
12 #define _FFT_FFT_H_
13 
14 /*
15  * Wrappers for FFTW single precision 1d dft
16  */
17 
18 #include <gnuradio/fft/api.h>
19 #include <gnuradio/gr_complex.h>
20 #include <gnuradio/logger.h>
21 #include <volk/volk_alloc.hh>
22 #include <mutex>
23 
24 namespace gr {
25 namespace fft {
26 
27 /*!
28  * \brief Export reference to planner mutex for those apps that
29  * want to use FFTW w/o using the fft_impl_fftw* classes.
30  */
32 {
33 public:
34  /*!
35  * Return reference to planner mutex
36  */
37  static std::mutex& mutex();
38 };
39 
40 
41 /*!
42  \brief FFT: templated
43  \ingroup misc
44  */
45 
46 
47 template <class T, bool forward>
48 struct fft_inbuf {
49  typedef T type;
50 };
51 
52 template <>
53 struct fft_inbuf<float, false> {
54  typedef gr_complex type;
55 };
56 
57 
58 template <class T, bool forward>
59 struct fft_outbuf {
60  typedef T type;
61 };
62 
63 template <>
64 struct fft_outbuf<float, true> {
65  typedef gr_complex type;
66 };
67 
68 template <class T, bool forward>
69 class FFT_API fft
70 {
71  int d_nthreads;
72  volk::vector<typename fft_inbuf<T, forward>::type> d_inbuf;
73  volk::vector<typename fft_outbuf<T, forward>::type> d_outbuf;
74  void* d_plan;
75  gr::logger d_logger;
76  void initialize_plan(int fft_size);
77 
78 public:
79  fft(int fft_size, int nthreads = 1);
80  // Copy disabled due to d_plan.
81  fft(const fft&) = delete;
82  fft& operator=(const fft&) = delete;
83  virtual ~fft();
84 
85  /*
86  * These return pointers to buffers owned by fft_impl_fft_complex
87  * into which input and output take place. It's done this way in
88  * order to ensure optimal alignment for SIMD instructions.
89  */
90  typename fft_inbuf<T, forward>::type* get_inbuf() { return d_inbuf.data(); }
91  typename fft_outbuf<T, forward>::type* get_outbuf() { return d_outbuf.data(); }
92 
93  int inbuf_length() const { return d_inbuf.size(); }
94  int outbuf_length() const { return d_outbuf.size(); }
95 
96  /*!
97  * Set the number of threads to use for calculation.
98  */
99  void set_nthreads(int n);
100 
101  /*!
102  * Get the number of threads being used by FFTW
103  */
104  int nthreads() const { return d_nthreads; }
105 
106  /*!
107  * compute FFT. The input comes from inbuf, the output is placed in
108  * outbuf.
109  */
110  void execute();
111 };
112 
117 
118 } /* namespace fft */
119 } /*namespace gr */
120 
121 #endif /* _FFT_FFT_H_ */
Definition: fft.h:70
fft(const fft &)=delete
fft & operator=(const fft &)=delete
int inbuf_length() const
Definition: fft.h:93
fft_outbuf< T, forward >::type * get_outbuf()
Definition: fft.h:91
void execute()
fft(int fft_size, int nthreads=1)
int outbuf_length() const
Definition: fft.h:94
virtual ~fft()
fft_inbuf< T, forward >::type * get_inbuf()
Definition: fft.h:90
void set_nthreads(int n)
int nthreads() const
Definition: fft.h:104
Export reference to planner mutex for those apps that want to use FFTW w/o using the fft_impl_fftw* c...
Definition: fft.h:32
static std::mutex & mutex()
GR_LOG macros.
Definition: logger.h:121
#define FFT_API
Definition: gr-fft/include/gnuradio/fft/api.h:18
std::complex< float > gr_complex
Definition: gr_complex.h:15
boost::mutex mutex
Definition: thread.h:37
GNU Radio logging wrapper.
Definition: basic_block.h:29
gr_complex type
Definition: fft.h:54
FFT: templated.
Definition: fft.h:48
T type
Definition: fft.h:49
gr_complex type
Definition: fft.h:65
Definition: fft.h:59
T type
Definition: fft.h:60