2 * Author: Brendan Le Foll <brendan.le.foll@intel.com>
3 * Copyright (c) 2014 Intel Corporation.
5 * Permission is hereby granted, free of charge, to any person obtaining
6 * a copy of this software and associated documentation files (the
7 * "Software"), to deal in the Software without restriction, including
8 * without limitation the rights to use, copy, modify, merge, publish,
9 * distribute, sublicense, and/or sell copies of the Software, and to
10 * permit persons to whom the Software is furnished to do so, subject to
11 * the following conditions:
13 * The above copyright notice and this permission notice shall be
14 * included in all copies or substantial portions of the Software.
16 * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND,
17 * EXPRESS OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF
18 * MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND
19 * NONINFRINGEMENT. IN NO EVENT SHALL THE AUTHORS OR COPYRIGHT HOLDERS BE
20 * LIABLE FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER IN AN ACTION
21 * OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN CONNECTION
22 * WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE SOFTWARE.
34 Microphone::Microphone(int micPin) {
35 // initialise analog mic input
36 m_micCtx = maa_aio_init(micPin);
41 Microphone::~Microphone() {
44 error = maa_aio_close(m_micCtx);
45 if (error != MAA_SUCCESS) {
46 maa_result_print(error);
51 Microphone::getSampledWindow (unsigned int freqMS, unsigned int numberOfSamples,
61 if (numberOfSamples > 0xFFFFFF) {
65 while (sampleIdx < numberOfSamples) {
66 buffer[sampleIdx++] = maa_aio_read (m_micCtx);
67 usleep(freqMS * 1000);
74 Microphone::findThreshold (thresholdContext* ctx, unsigned int threshold,
75 uint16_t * buffer, unsigned int len) {
77 for (unsigned int i = 0; i < len; i++) {
81 ctx->averageReading = sum / len;
82 ctx->runningAverage = (((ctx->averagedOver-1) * ctx->runningAverage) + ctx->averageReading) / ctx->averagedOver;
84 if (ctx->runningAverage > threshold) {
85 return ctx->runningAverage;
92 Microphone::printGraph (thresholdContext* ctx) {
93 for (int i = 0; i < ctx->runningAverage; i++)
95 std::cout << std::endl;