widget.cpp Example File

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  ** Contact: https://www.qt.io/licensing/
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  ** This file is part of the Qt Charts module of the Qt Toolkit.
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  #include "widget.h"
  #include <QtMultimedia/QAudioDeviceInfo>
  #include <QtMultimedia/QAudioInput>
  #include <QtCharts/QChartView>
  #include <QtCharts/QLineSeries>
  #include <QtCharts/QChart>
  #include <QtWidgets/QVBoxLayout>
  #include <QtCharts/QValueAxis>
  #include "xyseriesiodevice.h"

  QT_CHARTS_USE_NAMESPACE

  Widget::Widget(QWidget *parent)
      : QWidget(parent),
        m_device(0),
        m_chart(0),
        m_series(0),
        m_audioInput(0)
  {
      m_chart = new QChart;
      QChartView *chartView = new QChartView(m_chart);
      chartView->setMinimumSize(800, 600);
      m_series = new QLineSeries;
      m_chart->addSeries(m_series);
      QValueAxis *axisX = new QValueAxis;
      axisX->setRange(0, 2000);
      axisX->setLabelFormat("%g");
      axisX->setTitleText("Samples");
      QValueAxis *axisY = new QValueAxis;
      axisY->setRange(-1, 1);
      axisY->setTitleText("Audio level");
      m_chart->setAxisX(axisX, m_series);
      m_chart->setAxisY(axisY, m_series);
      m_chart->legend()->hide();
      m_chart->setTitle("Data from the microphone");

      QVBoxLayout *mainLayout = new QVBoxLayout;
      mainLayout->addWidget(chartView);
      setLayout(mainLayout);

      QAudioFormat formatAudio;
      formatAudio.setSampleRate(8000);
      formatAudio.setChannelCount(1);
      formatAudio.setSampleSize(8);
      formatAudio.setCodec("audio/pcm");
      formatAudio.setByteOrder(QAudioFormat::LittleEndian);
      formatAudio.setSampleType(QAudioFormat::UnSignedInt);

      QAudioDeviceInfo inputDevices = QAudioDeviceInfo::defaultInputDevice();
      m_audioInput = new QAudioInput(inputDevices,formatAudio, this);

      m_device = new XYSeriesIODevice(m_series, this);
      m_device->open(QIODevice::WriteOnly);

      m_audioInput->start(m_device);
  }

  Widget::~Widget()
  {
      m_audioInput->stop();
      m_device->close();
  }