Play midi file .. problem 4.8.6

SherifOmran

Hello guys,

i had a program that was programmed under mac and it worked fine but now i am testing it under windows
my problem is that i need to play a midi file .. I use the following way, when i emit the startbackgroundsound signal

@
qDebug() << "background sound = " << bgsound;
// ouput = background sound = "C:\Users\Sherif\AppData\Local\login\spacegamebackground.mid"

QPointer &lt;QSound> backgroundsound = new QSound(bgsound);
QObject::connect(this,SIGNAL(StartBackGroundSoundSignal()),backgroundsound.data(),SLOT(play()));

emit(StartBackGroundSoundSignal());

@

what happens is that it beeps and does not play it ..
Could it be that there is a missing file? I am running from inside QT .. !!

please advice ..

thanks

SGaist

Hi,

Are you really passing

@ "C:\Users\Sherif\AppData\Local\login\spacegamebackground.mid"@

as path ?

If so you must either escape the backslashes or even better, since you are using Qt, use the forward slash *nix notation.

Hope it helps

SherifOmran

I could not solve the issue .. any help? I tested again under MAC but does not play any more

mainwindow.cpp
@
#include "mainwindow.h"
#include "ui_mainwindow.h"
#include <QPointer>
#include <QSound>

MainWindow::MainWindow(QWidget *parent) :
QMainWindow(parent),
ui(new Ui::MainWindow)
{
ui->setupUi(this);

QPointer <QSound> backgroundsound = new QSound("/Volumes/DATA/Win/bp.mid");
// connect background signal
backgroundsound->play();

}

MainWindow::~MainWindow()
{
delete ui;
}
@

mainwindow.h
@
#ifndef MAINWINDOW_H
#define MAINWINDOW_H

#include <QWidget>
#include <QtCore>
#include <QtGui>

#include <QMainWindow>

namespace Ui {
class MainWindow;
}

class MainWindow : public QMainWindow
{
Q_OBJECT

public:
explicit MainWindow(QWidget *parent = 0);
~MainWindow();
QPointer <QSound> backgroundsound ;

private:
Ui::MainWindow *ui;

};

#endif // MAINWINDOW_H
@

andreyc

The "description":http://qt-project.org/doc/qt-4.8/qsound.html#details says that on Windows QSound supports only WAV format.
And on MacOSX it supports whatever NSSound supports, which I guess, includes MIDI.

SherifOmran

thanks for the info, but do you know how can i play a midi file?

utcenter

You can use libraries like RTMIDI to read the actual midi, but you will still have to find a way to produce actual musical notes from the midi data, look for some synthesizer libraries.

SherifOmran

I found the following code online. I need to convert this form into a normal .h file so that i can include it as a class in any c file. I don't know this syntax and when i made a header file out of it, it did not work .. Could any body help? thank ..

@
/*

QtPlaySMF
Part of QtMidi (http://github.com/waddlesplash/qtmidi).
Copyright (c) 2003-2012 by David G. Slomin
Copyright (c) 2012 WaddleSplash
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 <stdio.h>
#include <QThread>
#include <QElapsedTimer>
#include <QCoreApplication>
#include <QMidiOut.h>
#include <QMidiFile.h>

class MidiPlayer : public QThread
{
Q_OBJECT
public:
MidiPlayer(QMidiFile* file, QMidiOut* out)
{ midi_file = file; midi_out = out; }
//MidiPlayer();

void play();

private:
QMidiEvent* midi_file_event;
QMidiFile* midi_file;
QMidiOut* midi_out;

protected:
void run()
{
QElapsedTimer t;
t.start();
QList<QMidiEvent*>* events = midi_file->events();
for(int i = 0; i < events->count(); i++)
{
midi_file_event = events->at(i);
if (midi_file_event->type() != QMidiEvent::Meta)
{
qint64 event_time = midi_file->timeFromTick(midi_file_event->tick()) * 1000;

            qint32 waitTime = event_time - t.elapsed();
            if(waitTime > 0) {
                msleep(waitTime);
            }
            handleEvent();
        }
    }

    midi_out->disconnect();
}

private slots:
void handleEvent()
{
if (midi_file_event->type() == QMidiEvent::SysEx)
{ // TODO: sysex
}
else
{
qint32 message = midi_file_event->message();
midi_out->sendMsg(message);
}
}
};

void MidiPlayer::play()
{
QString filename = "D:/Release/Win/bg.mid";
QString midiOutName = "";
QMidiFile* midi_file = new QMidiFile();
midi_file->load(filename);

QMidiOut* midi_out = new QMidiOut();
midi_out->connect(midiOutName);
MidiPlayer* p = new MidiPlayer(midi_file,midi_out);
p->start();

}
#include "playsmf.moc"

int main(int argc, char *argv[])
{
QCoreApplication a(argc,argv);

MidiPlayer *aa;
aa->play();

//QObject::connect(p,SIGNAL(finished()),&a,SLOT(quit()));

return a.exec(&#41;;

}

@

SherifOmran

Here is my header file and c file

problem: prototype does not match

@

#ifndef MIDICLASS_H
#define MIDICLASS_H

#include <stdio.h>
#include <QThread>
#include <QElapsedTimer>
#include <QCoreApplication>
#include <QMidiOut.h>
#include <QMidiFile.h>

class midiclass : public QThread
{
Q_OBJECT
public:
explicit midiclass(QMidiFile* file, QMidiOut* out)
{ midi_file = file; midi_out = out; }
//MidiPlayer();

void play();

private:
QMidiEvent* midi_file_event;
QMidiFile* midi_file;
QMidiOut* midi_out;

signals:
protected:
void run()
{
QElapsedTimer t;
t.start();
QList<QMidiEvent*>* events = midi_file->events();
for(int i = 0; i < events->count(); i++)
{
midi_file_event = events->at(i);
if (midi_file_event->type() != QMidiEvent::Meta)
{
qint64 event_time = midi_file->timeFromTick(midi_file_event->tick()) * 1000;

            qint32 waitTime = event_time - t.elapsed();
            if(waitTime > 0) {
                msleep(waitTime);
            }
            handleEvent();
        }
    }

    midi_out->disconnect();
}

private slots:
void handleEvent()
{
if (midi_file_event->type() == QMidiEvent::SysEx)
{ // TODO: sysex
}
else
{
qint32 message = midi_file_event->message();
midi_out->sendMsg(message);
}
}
};

#endif // MIDICLASS_H

@

here is my .c file

@
#include "midiclass.h"

midiclass::midiclass(QThread *parent) :
QObject(parent)
{

}

void midiclass::play()
{
QString filename = "D:/Activate Software/typing tutor MAC/login/Release/Win/bg.mid";
QString midiOutName = "";
QMidiFile* midi_file = new QMidiFile();
midi_file->load(filename);

QMidiOut* midi_out = new QMidiOut();
midi_out->connect(midiOutName);
MidiPlayer* p = new MidiPlayer(midi_file,midi_out);
p->start();

}

@

SherifOmran

any help

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Play midi file .. problem 4.8.6