QSet<int> SpectrumAnalyzer::analyzeFT(int range, const QVector<float> &data)
{
const float average = std::accumulate(data.begin(), data.end(), .0f) / data.size();
const float threshold = qMax(50 * average, .1f * data.size());
QSet<int> pressedKeys;
for (int i = 1; i < data.size() / 2; ++i)
{
if (isPeak(&data[i], threshold) && !isPeak(&data[i/2], threshold))
{
const float freq = float(m_sampleRate) * i / data.size();
const int nTasto = qRound(12 * log2(freq / 440) + 48);
if (nTasto >= m_ranges[range]->firstKey && nTasto <= m_ranges[range]->lastKey)
pressedKeys.insert(nTasto);
}
}
emit spectrumAvailable(range, data, threshold);
return pressedKeys;
}
// constructor: warm up all stuff
MainWindow::MainWindow(QWidget *parent) :
QMainWindow(parent),
ui(new Ui::MainWindow)
//,audioInfo(QAudioDeviceInfo::defaultInputDevice())
{
// draws the ui
ui->setupUi(this);
// test for saving settings
QCoreApplication::setOrganizationName("Agostinho");
/** some settings attempt
*/
QSettings settings; /*!<aloha */
settings.setValue("alo","maria");
// defines sample size equals to spectrum size
sample.resize(SPECSIZE);
// threads are as separate processes running within the same
// program. for fft calculation, it is better to move it
// to another thread to make the calcs faster.
// moreover, it will not slow down the ui
// fftThread = new QThread(this);
calculator = new FFTCalc();
// calculator->moveToThread(fftThread);
// launches the new media player
player = new QMediaPlayer();
// starts a new playlist
playlist = new QMediaPlaylist();
// starts the playlist model
playlistModel = new PlaylistModel(this);
// tell playlistmodel where is the playlist
playlistModel->setPlaylist(playlist);
// attach the listView to the playlistModel
ui->listViewPlaylist->setModel(playlistModel);
// set current index to the first element
ui->listViewPlaylist->setCurrentIndex(playlistModel->index(playlist->currentIndex(), 0));
loadPlaylist();
// attachs the playlist to the player
player->setPlaylist(playlist);
// playlist plays in loop mode. It restarts after last song has finished playing.
playlist->setPlaybackMode(QMediaPlaylist::Loop);
// this allow the user to select the media it wants to play
connect(ui->listViewPlaylist, SIGNAL(doubleClicked(QModelIndex)),
this, SLOT(goToItem(QModelIndex)));
// if some metadata changed for media, display it somewhere
// it seems not work on windows
// but works for linux :)
connect(player,SIGNAL(metaDataChanged()),
this, SLOT(metaDataChanged()));
// the media status changed (new stream has arrived)
connect(player, SIGNAL(mediaStatusChanged(QMediaPlayer::MediaStatus)),
this, SLOT(mediaStatusChanged(QMediaPlayer::MediaStatus)));
// the user selected a new position on music to play
// perharps using some scrollbar
connect(this,SIGNAL(positionChanged(qint64)),
player,SLOT(setPosition(qint64)));
connect(player,SIGNAL(volumeChanged(int)),
ui->control,SLOT(onVolumeChanged(int)));
connect(player,SIGNAL(stateChanged(QMediaPlayer::State)),
SLOT(mediaStateChanged(QMediaPlayer::State)));
// that is the audio probe object that "listen to"
// the music. It will help with fft stuff
probe = new QAudioProbe();
// fft is delivered using a QVector<double> but
// signal/slot scheme does not recognizes this type by default
// therefore, we have to register it
qRegisterMetaType< QVector<double> >("QVector<double>");
// here goes the control unit event handlers
connect(ui->control, SIGNAL(playPause()), this, SLOT(playPause()));
connect(ui->control, SIGNAL(prev()), this, SLOT(prev()));
connect(ui->control, SIGNAL(next()), this, SLOT(next()));
connect(this, SIGNAL(playPauseChanged(bool)),
ui->control,SLOT(onPlayerStateChanged(bool)));
// when the music position changes on player, it has to be
// informed to the control unit to redraw it ui
connect(player, SIGNAL(positionChanged(qint64)),
ui->control,SLOT(onElapsedChanged(qint64)));
// fft goes here...
// if a new audio buffer is ok, we have to make some
// calcs (fft) to display the spectrum
connect(probe, SIGNAL(audioBufferProbed(QAudioBuffer)),
this, SLOT(processBuffer(QAudioBuffer)));
// when fft is available, we deliver it to
// the visualization widget
connect(this, SIGNAL(spectrumChanged(QVector<double>&)),
ui->visualizer,SLOT(loadSamples(QVector<double>&)));
// communicate the left and right audio levels...
// ...mean levels
connect(this, SIGNAL(levels(double,double)),
ui->visualizer,SLOT(loadLevels(double,double)));
// when fft is available, we deliver it to
// the visualization widget
//connect(this, SIGNAL(spectrumChanged(QVector<double>&)),
// ui->glVisualizer,SLOT(loadSamples(QVector<double>&)));
// communicate the left and right audio levels...
// ...mean levels
//connect(this, SIGNAL(levels(double,double)),
// ui->glVisualizer,SLOT(loadLevels(double,double)));
// if the user selected a new position on stream to play
// we have to tell it to the player
connect(ui->control, SIGNAL(elapsedSelected(qint64)),
player, SLOT(setPosition(qint64)));
// changing audio volume
connect(ui->control, SIGNAL(volumeSelected(int)),
player, SLOT(setVolume(int)));
// calculator is the thead that calcs the ffts we need to display
// every time a new spectrum is available, the calculator
// emits a calculatedSpectrum signal
connect(calculator, SIGNAL(calculatedSpectrum(QVector<double>)),
this, SLOT(spectrumAvailable(QVector<double>)));
connect(ui->library,SIGNAL(addMediaToPlayList(QString)),
SLOT(onAddMediaToPlayList(QString)));
// tells the probe what to probe
probe->setSource(player);
// load directories to library
connect(ui->actionLoadDirectory,SIGNAL(triggered()),this,SLOT(onAddFolderToLibrary()));
// load a single file to library
connect(ui->actionLoadFile,SIGNAL(triggered()),this,SLOT(loadMedia()));
// it connects the signals emiteds via the visualizer to the buttons (ui->control) and the lightCycle(ui->widgetInfo)
connect(ui->visualizer,SIGNAL(trocaCor(QColor)),ui->control,SLOT(onColorChanged(QColor)));
connect(ui->visualizer,SIGNAL(trocaCor(QColor)),ui->widgetInfo,SLOT(changedColor(QColor)));
//this->setStyleSheet(QString("QMainWindow {background-color: black}"));
}