annotate data/fileio/MIDIFileWriter.h @ 490:c3fb8258e34d

* Make it possible to import an entire session from an RDF document.
  However, at the moment the timings of events appear to be constrained
  by how far the audio decoder has got through its audio file at the
  time the event is queried -- need to investigate.

/* -*- c-basic-offset: 4 indent-tabs-mode: nil -*-  vi:set ts=8 sts=4 sw=4: */

/*
    Sonic Visualiser
    An audio file viewer and annotation editor.
    Centre for Digital Music, Queen Mary, University of London.
    
    This program 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.  See the file
    COPYING included with this distribution for more information.
*/


/*
   This is a modified version of a source file from the 
   Rosegarden MIDI and audio sequencer and notation editor.
   This file copyright 2000-2007 Richard Bown and Chris Cannam
   and copyright 2007 QMUL.
*/

#ifndef _MIDI_FILE_WRITER_H_
#define _MIDI_FILE_WRITER_H_

#include "base/RealTime.h"

#include <QString>

#include <vector>
#include <map>
#include <fstream>

class MIDIEvent;
class NoteModel;

/**
 * Write a MIDI file.  This includes file write code for generic
 * simultaneous-track MIDI files, but the conversion stage only
 * supports a single-track MIDI file with fixed tempo, time signature
 * and timing division.
 */
class MIDIFileWriter 
{
public:
    MIDIFileWriter(QString path, NoteModel *model, float tempo = 120.f);
    virtual ~MIDIFileWriter();

    virtual bool isOK() const;
    virtual QString getError() const;

    virtual void write();

protected:
    typedef std::vector<MIDIEvent *> MIDITrack;
    typedef std::map<unsigned int, MIDITrack> MIDIComposition;

    typedef enum {
	MIDI_SINGLE_TRACK_FILE          = 0x00,
	MIDI_SIMULTANEOUS_TRACK_FILE    = 0x01,
	MIDI_SEQUENTIAL_TRACK_FILE      = 0x02,
	MIDI_FILE_BAD_FORMAT            = 0xFF
    } MIDIFileFormatType;

    std::string intToMIDIBytes(int number) const;
    std::string longToMIDIBytes(unsigned long number) const;
    std::string longToVarBuffer(unsigned long number) const;

    unsigned long getMIDITimeForTime(RealTime t) const;

    bool writeHeader();
    bool writeTrack(int track);
    bool writeComposition();
    
    bool convert();

    QString             m_path;
    NoteModel          *m_model;
    bool                m_modelUsesHz;
    float               m_tempo;
    int                 m_timingDivision;   // pulses per quarter note
    MIDIFileFormatType  m_format;
    unsigned int        m_numberOfTracks;

    MIDIComposition     m_midiComposition;

    std::ofstream      *m_midiFile;
    QString             m_error;
};

#endif