GNU Radio Manual and C++ API Reference  3.7.9.2
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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
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22 
23 #ifndef INCLUDED_BLOCKS_DELAY_H
24 #define INCLUDED_BLOCKS_DELAY_H
25 
26 #include <gnuradio/blocks/api.h>
27 #include <gnuradio/block.h>
28 
29 namespace gr {
30  namespace 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  */
44  class BLOCKS_API delay : virtual public block
45  {
46  public:
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 */
boost::shared_ptr< delay > sptr
Definition: delay.h:48
delay the input by a certain number of samplesPositive delays insert zero items at the beginning of t...
Definition: delay.h:44
Include this header to use the message passing features.
Definition: logger.h:131
#define BLOCKS_API
Definition: gr-blocks/include/gnuradio/blocks/api.h:30
The abstract base class for all 'terminal' processing blocks.A signal processing flow is constructed ...
Definition: block.h:60
BLOCKS_API size_t itemsize(vector_type type)