GNU Radio Manual and C++ API Reference 3.7.14.0
The Free & Open Software Radio Ecosystem
delay.h
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1/* -*- c++ -*- */
2/*
3 * Copyright 2007,2012-2013 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
23#ifndef INCLUDED_BLOCKS_DELAY_H
24#define INCLUDED_BLOCKS_DELAY_H
25
26#include <gnuradio/block.h>
27#include <gnuradio/blocks/api.h>
28
29namespace gr {
30namespace blocks {
31
32/*!
33 * \brief delay the input by a certain number of samples
34 * \ingroup misc_blk
35 *
36 * Positive delays insert zero items at the beginning of the stream.
37 * Negative delays discard items from the stream.
38 *
39 * You cannot initialize this block with a negative delay,
40 * however. That leads to a causality issue with the buffers when
41 * they are initialized. If you need to negetively delay one path,
42 * then put the positive delay on the other path instead.
43 */
44class BLOCKS_API delay : virtual public block
45{
46public:
47 // gr::blocks::delay::sptr
48 typedef boost::shared_ptr<delay> sptr;
49
50 /*!
51 * \brief Make a delay block.
52 * \param itemsize size of the data items.
53 * \param delay number of samples to delay stream (>= 0).
54 */
55 static sptr make(size_t itemsize, int delay);
56
57 virtual int dly() const = 0;
58
59 /*!
60 * \brief Reset the delay.
61 * \param d change the delay value. This can be a positive or
62 * negative value.
63 */
64 virtual void set_dly(int d) = 0;
65};
66
67} /* namespace blocks */
68} /* namespace gr */
69
70#endif /* INCLUDED_BLOCKS_DELAY_H */
The abstract base class for all 'terminal' processing blocks.
Definition: block.h:66
delay the input by a certain number of samples
Definition: delay.h:45
boost::shared_ptr< delay > sptr
Definition: delay.h:48
virtual int dly() const =0
virtual void set_dly(int d)=0
Reset the delay.
static sptr make(size_t itemsize, int delay)
Make a delay block.
#define BLOCKS_API
Definition: gr-blocks/include/gnuradio/blocks/api.h:30
BLOCKS_API size_t itemsize(vector_type type)
Include this header to use the message passing features.
Definition: basic_block.h:45