1 /* -*- c++ -*- */
2 /*
3 * Copyright 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 #ifdef HAVE_CONFIG_H
24 #include "config.h"
25 #endif
26
27 #include "plateau_detector_fb_impl.h"
28 #include <gnuradio/io_signature.h>
29
30 namespace gr {
31 namespace blocks {
32
make(int max_len,float threshold)33 plateau_detector_fb::sptr plateau_detector_fb::make(int max_len, float threshold)
34 {
35 return gnuradio::get_initial_sptr(new plateau_detector_fb_impl(max_len, threshold));
36 }
37
plateau_detector_fb_impl(int max_len,float threshold)38 plateau_detector_fb_impl::plateau_detector_fb_impl(int max_len, float threshold)
39 : block("plateau_detector_fb",
40 io_signature::make(1, 1, sizeof(float)),
41 io_signature::make(1, 1, sizeof(char))),
42 d_max_len(max_len),
43 d_threshold(threshold)
44 {
45 }
46
~plateau_detector_fb_impl()47 plateau_detector_fb_impl::~plateau_detector_fb_impl() {}
48
forecast(int,gr_vector_int & ninput_items_required)49 void plateau_detector_fb_impl::forecast(int, gr_vector_int& ninput_items_required)
50 {
51 ninput_items_required[0] = 2 * d_max_len;
52 }
53
general_work(int noutput_items,gr_vector_int & ninput_items,gr_vector_const_void_star & input_items,gr_vector_void_star & output_items)54 int plateau_detector_fb_impl::general_work(int noutput_items,
55 gr_vector_int& ninput_items,
56 gr_vector_const_void_star& input_items,
57 gr_vector_void_star& output_items)
58 {
59 // thread-safe protection from ::set_threshold
60 gr::thread::scoped_lock l(d_setlock);
61
62 const float* in = (const float*)input_items[0];
63 unsigned char* out = (unsigned char*)output_items[0];
64 int flank_start;
65 noutput_items = std::min(noutput_items, ninput_items[0]);
66 memset((void*)out, 0x00, noutput_items);
67 int i;
68 for (i = 0; i < noutput_items; i++) {
69 if (in[i] >= d_threshold) {
70 if (noutput_items - i <
71 2 * d_max_len) { // If we can't finish, come back later
72 break;
73 }
74 flank_start = i;
75 while (i < noutput_items && in[i] >= d_threshold)
76 i++;
77 if ((i - flank_start) > 1) { // 1 Sample is not a plateau
78 out[flank_start + (i - flank_start) / 2] = 1;
79 i = std::min(i + d_max_len, noutput_items - 1);
80 }
81 }
82 }
83
84 this->consume_each(i);
85 return i;
86 }
87
set_threshold(float threshold)88 void plateau_detector_fb_impl::set_threshold(float threshold)
89 {
90 // thread-safe protection from ::set_threshold
91 gr::thread::scoped_lock l(d_setlock);
92 d_threshold = threshold;
93 }
94
threshold() const95 float plateau_detector_fb_impl::threshold() const { return d_threshold; }
96
97 } /* namespace blocks */
98 } /* namespace gr */
99