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
96
97
98
99
100
101
102
|
/*
* Author: Brendan Le Foll <brendan.le.foll@intel.com>
* Copyright (c) 2014 Intel Corporation.
*
* Permission is hereby granted, free of charge, to any person obtaining
* a copy of this software and associated documentation files (the
* "Software"), to deal in the Software without restriction, including
* without limitation the rights to use, copy, modify, merge, publish,
* distribute, sublicense, and/or sell copies of the Software, and to
* permit persons to whom the Software is furnished to do so, subject to
* the following conditions:
*
* The above copyright notice and this permission notice shall be
* included in all copies or substantial portions of the Software.
*
* THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND,
* EXPRESS OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF
* MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND
* NONINFRINGEMENT. IN NO EVENT SHALL THE AUTHORS OR COPYRIGHT HOLDERS BE
* LIABLE FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER IN AN ACTION
* OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN CONNECTION
* WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE SOFTWARE.
*/
#include <iostream>
#include <string>
#include <stdexcept>
#include <unistd.h>
#include <stdlib.h>
#include <functional>
#include <string.h>
#include "mic.h"
using namespace upm;
Microphone::Microphone(int micPin) {
// initialise analog mic input
if ( !(m_micCtx = mraa_aio_init(micPin)) )
{
throw std::invalid_argument(std::string(__FUNCTION__) +
": mraa_aio_init() failed, invalid pin?");
return;
}
}
Microphone::~Microphone() {
// close analog input
mraa_result_t error;
error = mraa_aio_close(m_micCtx);
if (error != MRAA_SUCCESS) {
mraa_result_print(error);
}
}
int
Microphone::getSampledWindow (unsigned int freqMS, int numberOfSamples,
uint16_t * buffer) {
int sampleIdx = 0;
// must have freq
if (!freqMS) {
return 0;
}
// too much samples
if (numberOfSamples > 0xFFFFFF) {
return 0;
}
while (sampleIdx < numberOfSamples) {
buffer[sampleIdx++] = mraa_aio_read (m_micCtx);
usleep(freqMS * 1000);
}
return sampleIdx;
}
int
Microphone::findThreshold (thresholdContext* ctx, unsigned int threshold,
uint16_t * buffer, int len) {
long sum = 0;
for (unsigned int i = 0; i < len; i++) {
sum += buffer[i];
}
ctx->averageReading = sum / len;
ctx->runningAverage = (((ctx->averagedOver-1) * ctx->runningAverage) + ctx->averageReading) / ctx->averagedOver;
if (ctx->runningAverage > threshold) {
return ctx->runningAverage;
} else {
return 0;
}
}
void
Microphone::printGraph (thresholdContext* ctx) {
for (int i = 0; i < ctx->runningAverage; i++)
std::cout << ".";
std::cout << std::endl;
}
|
