summaryrefslogtreecommitdiff
path: root/gr-atsc/src/lib/GrAtscFieldSyncCorrelator.cc
blob: 4cbf17103646bd5a3d5c9db5b0f770cd2480a030 (plain)
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
/* -*- c++ -*- */
/*
 * Copyright 2002 Free Software Foundation, Inc.
 * 
 * This file is part of GNU Radio
 * 
 * GNU Radio is free software; you can redistribute it and/or modify
 * it under the terms of the GNU General Public License as published by
 * the Free Software Foundation; either version 3, or (at your option)
 * any later version.
 * 
 * GNU Radio is distributed in the hope that it will be useful,
 * but WITHOUT ANY WARRANTY; without even the implied warranty of
 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
 * GNU General Public License for more details.
 * 
 * You should have received a copy of the GNU General Public License
 * along with GNU Radio; see the file COPYING.  If not, write to
 * the Free Software Foundation, Inc., 51 Franklin Street,
 * Boston, MA 02110-1301, USA.
 */

#include <GrAtscFieldSyncCorrelator.h>
#include <create_atsci_fs_correlator.h>
#include <atsci_fs_correlator.h>

// typedefs for fundamental i/o types

typedef float	iType;
typedef float	oType;

static const int NUMBER_OF_OUTPUTS = 2;	// # of output streams 


GrAtscFieldSyncCorrelator::GrAtscFieldSyncCorrelator ()
  : VrHistoryProc<iType,oType> (NUMBER_OF_OUTPUTS)
{
  // 1 + number of extra input elements at which we look.  This is
  // used by the superclass's forecast routine to get us the correct
  // range on our inputs.
  // We're one-to-one input-to-output so set it to 1.
  history = 1;	

  d_fsc = create_atsci_fs_correlator ();
}

GrAtscFieldSyncCorrelator::~GrAtscFieldSyncCorrelator ()
{
  // Anything that isn't automatically cleaned up...

  delete d_fsc;
}

/*
 * This is the real work horse.  In general this interface can handle
 * multiple streams of input and output, but we almost always
 * use a single input and output stream.
 */

int 
GrAtscFieldSyncCorrelator::work (VrSampleRange output, void *ao[],
				 VrSampleRange inputs[], void *ai[])
{
  // If we have state that persists across invocations (e.g., we have
  // instance variables that we modify), we must use the sync method
  // to indicate to the scheduler that our output must be computed in
  // order.  This doesn't keep other things from being run in
  // parallel, it just means that at any given time, there is only a
  // single thread working this code, and that the scheduler will
  // ensure that we are asked to produce output that is contiguous and
  // that will be presented to us in order of increasing time.

  // We have state, hence we must use sync.

  sync (output.index);

  // construct some nicer i/o pointers to work with.

  iType *in  = ((iType **) ai)[0];
  oType *sample_out = ((oType **) ao)[0];
  oType *tag_out    = ((oType **) ao)[1];


  // We must produce output.size units of output.

  for (unsigned int i = 0; i < output.size; i++){
    d_fsc->filter (in[i], &sample_out[i], &tag_out[i]);
  }

  // Return the number of units we produced.
  // Note that for all intents and purposes, it is an error to
  // produce less than you are asked for.

  return output.size;
}