drumstick 0.5.0
metronome.cpp

Simple command line MIDI metronome.

Simple command line MIDI metronome

/*
Standard MIDI simple metronome
Copyright (C) 2006-2010, Pedro Lopez-Cabanillas <plcl@users.sf.net>
This library is free software; you can redistribute it and/or modify
it under the terms of the GNU General Public License as published by
the Free Software Foundation; either version 2 of the License, or
(at your option) any later version.
This library is distributed in the hope that it will be useful,
but WITHOUT ANY WARRANTY; without even the implied warranty of
MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
GNU General Public License for more details.
You should have received a copy of the GNU General Public License along
with this program; if not, write to the Free Software Foundation, Inc.,
51 Franklin Street, Fifth Floor, Boston, MA 02110-1301, USA.
*/
#ifndef METRONOME_H
#define METRONOME_H
#include "alsaevent.h"
#include "alsaclient.h"
#include "alsaqueue.h"
#include "alsaport.h"
#include <QObject>
#include <QString>
#include <QList>
#include <QReadWriteLock>
const int TEMPO_DEFAULT(120);
const int NOTE_DURATION(10);
const int RHYTHM_TS_NUM(4);
const int RHYTHM_TS_DEN(4);
const int METRONOME_CHANNEL(9);
const int METRONOME_STRONG_NOTE(34);
const int METRONOME_WEAK_NOTE(33);
const int METRONOME_VELOCITY(100);
const int METRONOME_PROGRAM(0);
const int METRONOME_RESOLUTION(240);
const int METRONOME_VOLUME(100);
const int METRONOME_PAN(64);
using namespace drumstick;
class Metronome : public QObject, public SequencerEventHandler
{
Q_OBJECT
public:
Metronome(QObject *parent = 0);
virtual ~Metronome();
void play(QString tempo);
bool stopped();
void stop();
void subscribe(const QString& portName);
void shutupSound();
//void usage();
//void info();
void sendControlChange( int cc, int value );
void sendInitialControls();
void metronome_note(int note, int tick);
void metronome_echo(int tick);
void metronome_pattern(int tick);
void metronome_event_output(SequencerEvent* ev);
void metronome_schedule_event(SequencerEvent* ev, int tick, bool lb);
void metronome_set_program();
void metronome_set_tempo();
void metronome_set_controls();
// SequencerEventHandler interface
void handleSequencerEvent( SequencerEvent* ev );
private:
int m_weak_note;
int m_strong_note;
int m_weak_velocity;
int m_strong_velocity;
int m_program;
int m_channel;
int m_volume;
int m_pan;
int m_resolution;
int m_bpm;
int m_ts_num; /* time signature: numerator */
int m_ts_div; /* time signature: denominator */
int m_noteDuration;
int m_patternDuration;
int m_portId;
int m_queueId;
int m_clientId;
bool m_Stopped;
QReadWriteLock m_mutex;
MidiClient* m_Client;
MidiPort* m_Port;
MidiQueue* m_Queue;
};
#endif /*METRONOME_H*/
Classes managing ALSA Sequencer clients.
Classes managing ALSA Sequencer events.
Classes managing ALSA Sequencer ports.
Classes managing ALSA Sequencer queues.
The QObject class is the base class of all Qt objects.
Client management.
Definition alsaclient.h:199
Port management.
Definition alsaport.h:120
Queue management.
Definition alsaqueue.h:189
Sequencer events handler.
Definition alsaclient.h:176
Base class for the event's hierarchy.
Definition alsaevent.h:54
/*
Standard MIDI simple metronome
Copyright (C) 2006-2010, Pedro Lopez-Cabanillas <plcl@users.sf.net>
This library is free software; you can redistribute it and/or modify
it under the terms of the GNU General Public License as published by
the Free Software Foundation; either version 2 of the License, or
(at your option) any later version.
This library is distributed in the hope that it will be useful,
but WITHOUT ANY WARRANTY; without even the implied warranty of
MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
GNU General Public License for more details.
You should have received a copy of the GNU General Public License along
with this program; if not, write to the Free Software Foundation, Inc.,
51 Franklin Street, Fifth Floor, Boston, MA 02110-1301, USA.
*/
#include "metronome.h"
#include "alsatimer.h"
#include "cmdlineargs.h"
#include <signal.h>
#include <QApplication>
#include <QTextStream>
#include <QtAlgorithms>
#include <QStringList>
#include <QReadLocker>
#include <QWriteLocker>
static QTextStream cout(stdout, QIODevice::WriteOnly);
static QTextStream cerr(stderr, QIODevice::WriteOnly);
/* *************** *
* Metronome class *
* *************** */
Metronome::Metronome(QObject *parent) : QObject(parent),
m_weak_note(METRONOME_WEAK_NOTE),
m_strong_note(METRONOME_STRONG_NOTE),
m_weak_velocity(METRONOME_VELOCITY),
m_strong_velocity(METRONOME_VELOCITY),
m_program(METRONOME_PROGRAM),
m_channel(METRONOME_CHANNEL),
m_volume(METRONOME_VOLUME),
m_pan(METRONOME_PAN),
m_resolution(METRONOME_RESOLUTION),
m_bpm(TEMPO_DEFAULT),
m_ts_num(RHYTHM_TS_NUM),
m_ts_div(RHYTHM_TS_DEN),
m_noteDuration(NOTE_DURATION),
m_portId(-1),
m_queueId(-1),
m_clientId(-1),
m_Stopped(true)
{
QLatin1String name("Metronome");
m_Client = new MidiClient(this);
m_Client->open();
m_Client->setClientName(name);
m_Client->setHandler(this);
m_Port = new MidiPort(this);
m_Port->attach( m_Client );
m_Port->setPortName(name);
m_Port->setCapability( SND_SEQ_PORT_CAP_READ |
SND_SEQ_PORT_CAP_SUBS_READ |
SND_SEQ_PORT_CAP_WRITE );
m_Port->setPortType( SND_SEQ_PORT_TYPE_MIDI_GENERIC |
SND_SEQ_PORT_TYPE_APPLICATION );
m_Queue = m_Client->createQueue(name);
m_clientId = m_Client->getClientId();
m_queueId = m_Queue->getId();
m_portId = m_Port->getPortId();
m_Port->setTimestamping(true);
m_Port->setTimestampQueue(m_queueId);
// Get and apply the best available timer
TimerId best = Timer::bestGlobalTimerId();
QueueTimer qtimer;
qtimer.setId(best);
m_Queue->setTimer(qtimer);
// Start sequencer input
m_Client->setRealTimeInput(false);
m_Client->startSequencerInput();
}
Metronome::~Metronome()
{
m_Port->detach();
m_Client->close();
}
void Metronome::handleSequencerEvent( SequencerEvent *ev )
{
if (ev->getSequencerType() == SND_SEQ_EVENT_USR0)
metronome_pattern(ev->getTick() + m_patternDuration);
delete ev;
}
void Metronome::metronome_event_output(SequencerEvent* ev)
{
ev->setSource(m_portId);
ev->setSubscribers();
ev->setDirect();
m_Client->outputDirect(ev);
}
void Metronome::sendControlChange(int cc, int value)
{
ControllerEvent ev(m_channel, cc, value);
metronome_event_output(&ev);
}
void Metronome::sendInitialControls()
{
metronome_set_program();
metronome_set_controls();
metronome_set_tempo();
}
void Metronome::metronome_set_program()
{
ProgramChangeEvent ev(m_channel, m_program);
metronome_event_output(&ev);
}
void Metronome::metronome_schedule_event(SequencerEvent* ev, int tick, bool lb)
{
ev->setSource(m_portId);
if (lb) // loop back
ev->setDestination(m_clientId, m_portId);
else
ev->setSubscribers();
ev->scheduleTick(m_queueId, tick, false);
m_Client->outputDirect(ev);
}
void Metronome::metronome_note(int note, int tick)
{
NoteEvent ev(m_channel, note, METRONOME_VELOCITY, m_noteDuration);
metronome_schedule_event(&ev, tick, false);
}
void Metronome::metronome_echo(int tick)
{
SystemEvent ev(SND_SEQ_EVENT_USR0);
metronome_schedule_event(&ev, tick, true);
}
void Metronome::metronome_pattern(int tick)
{
int j, t, duration;
t = tick;
duration = m_resolution * 4 / m_ts_div;
for (j = 0; j < m_ts_num; j++) {
metronome_note(j ? m_weak_note : m_strong_note, t);
t += duration;
}
metronome_echo(t);
}
void Metronome::metronome_set_tempo()
{
QueueTempo t = m_Queue->getTempo();
t.setPPQ(m_resolution);
t.setNominalBPM(m_bpm);
m_Queue->setTempo(t);
m_Client->drainOutput();
}
void Metronome::metronome_set_controls()
{
sendControlChange(MIDI_CTL_MSB_MAIN_VOLUME, m_volume);
sendControlChange(MIDI_CTL_MSB_PAN, m_pan);
}
void Metronome::subscribe(const QString& portName)
{
m_Port->subscribeTo(portName);
}
bool Metronome::stopped()
{
QReadLocker locker(&m_mutex);
return m_Stopped;
}
void Metronome::stop()
{
QWriteLocker locker(&m_mutex);
m_Stopped = true;
m_Client->dropOutput();
}
void Metronome::shutupSound()
{
sendControlChange( MIDI_CTL_ALL_NOTES_OFF, 0 );
sendControlChange( MIDI_CTL_ALL_SOUNDS_OFF, 0 );
}
void Metronome::play(QString tempo)
{
bool ok;
m_Stopped = false;
m_patternDuration = m_resolution * 4 / m_ts_div * m_ts_num;
m_bpm = tempo.toInt(&ok);
if (!ok) m_bpm = TEMPO_DEFAULT;
cout << "Metronome playing. " << m_bpm << " bpm" << endl;
cout << "Press Ctrl+C to exit" << endl;
try {
sendInitialControls();
m_Queue->start();
metronome_pattern(0);
metronome_pattern(m_patternDuration);
while (!stopped())
sleep(1);
} catch (const SequencerError& err) {
cerr << "SequencerError exception. Error code: " << err.code()
<< " (" << err.qstrError() << ")" << endl;
cerr << "Location: " << err.location() << endl;
}
}
/*
void Metronome::usage()
{
cout << "Error: wrong parameters" << endl;
cout << "Usage:" << endl;
cout << " metronome PORT BPM" << endl;
}
void Metronome::info()
{
SystemInfo info = m_Client->getSystemInfo();
cout << "ALSA Sequencer System Info" << endl;
cout << "Max Clients: " << info.getMaxClients() << endl;
cout << "Max Ports: " << info.getMaxPorts() << endl;
cout << "Max Queues: " << info.getMaxQueues() << endl;
cout << "Max Channels: " << info.getMaxChannels() << endl;
cout << "Current Queues: " << info.getCurrentQueues() << endl;
cout << "Current Clients: " << info.getCurrentClients() << endl;
}
*/
Metronome* metronome = 0;
void signalHandler(int sig)
{
if (sig == SIGINT)
qDebug() << "Caught a SIGINT. Exiting";
else if (sig == SIGTERM)
qDebug() << "Caught a SIGTERM. Exiting";
if (metronome != 0) {
metronome->stop();
metronome->shutupSound();
}
}
int main(int argc, char **argv)
{
const QString errorstr = "Fatal error from the ALSA sequencer. "
"This usually happens when the kernel doesn't have ALSA support, "
"or the device node (/dev/snd/seq) doesn't exists, "
"or the kernel module (snd_seq) is not loaded. "
"Please check your ALSA/MIDI configuration.";
CmdLineArgs args;
signal(SIGINT, signalHandler);
signal(SIGTERM, signalHandler);
args.setUsage("[options] port [bpm]");
args.addRequiredArgument("port", "Destination, MIDI port identifier");
args.addOptionalArgument("bpm", "Tempo, in beats per minute (default=120)");
args.parse(argc, argv);
try {
metronome = new Metronome();
QVariant port = args.getArgument("port");
if (!port.isNull())
metronome->subscribe(port.toString());
QVariant bpm = args.getArgument("bpm");
metronome->play(bpm.toString());
} catch (const SequencerError& ex) {
cerr << errorstr + " Returned error was: " + ex.qstrError() << endl;
} catch (...) {
cerr << errorstr << endl;
}
delete metronome;
return 0;
}
Classes managing ALSA Timers.