GNU Radio's DAB Package
dab_moving_sum_cc.h
Go to the documentation of this file.
1 /* -*- c++ -*- */
2 /*
3  * Copyright 2004 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
9  * the Free Software Foundation; either version 3, or (at your option)
10  * any later version.
11  *
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.
16  *
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.
21  */
22 #ifndef INCLUDED_DAB_MOVING_SUM_CC_H
23 #define INCLUDED_DAB_MOVING_SUM_CC_H
24 
25 #include <gr_sync_block.h>
26 
27 class dab_moving_sum_cc;
28 
29 typedef boost::shared_ptr<dab_moving_sum_cc> dab_moving_sum_cc_sptr;
30 
31 dab_moving_sum_cc_sptr dab_make_moving_sum_cc (int length);
32 
33 /*!
34  * \brief Moving sum over a stream of complex floats.
35  * \ingroup filter
36  * \param length length of the moving sum (=number of taps)
37  *
38  * input: complex
39  * output: complex
40  *
41  * This is the same as an FIR filter with length taps 1, but much faster
42  * (linear time instead of O(n*m)). On the other hand, since only the diff is
43  * calculated for each sample, there is some chance of an accumulating error.
44  */
45 class dab_moving_sum_cc : public gr_sync_block
46 {
47 private:
48  // The friend declaration allows dab_make_moving_sum_cc to
49  // access the private constructor.
50 
51  friend dab_moving_sum_cc_sptr dab_make_moving_sum_cc (int length);
52 
53  dab_moving_sum_cc (int length); // private constructor
54 
55  gr_complexd d_sum;
56  int d_length;
57 
58  public:
59  ~dab_moving_sum_cc (); // public destructor
60  int length() const {return d_length;}
61  void reset() {d_sum=0;}
62 
63  // Where all the action really happens
64 
65  int work (int noutput_items,
66  gr_vector_const_void_star &input_items,
67  gr_vector_void_star &output_items);
68 };
69 
70 #endif /* INCLUDED_DAB_MOVING_SUM_CC_H */
dab_moving_sum_cc::work
int work(int noutput_items, gr_vector_const_void_star &input_items, gr_vector_void_star &output_items)
dab_moving_sum_cc::~dab_moving_sum_cc
~dab_moving_sum_cc()
dab_moving_sum_cc
Moving sum over a stream of complex floats.
Definition: dab_moving_sum_cc.h:46
dab_moving_sum_cc::reset
void reset()
Definition: dab_moving_sum_cc.h:61
dab_make_moving_sum_cc
dab_moving_sum_cc_sptr dab_make_moving_sum_cc(int length)
dab_moving_sum_cc::dab_make_moving_sum_cc
friend dab_moving_sum_cc_sptr dab_make_moving_sum_cc(int length)
dab_moving_sum_cc::length
int length() const
Definition: dab_moving_sum_cc.h:60