/// <summary>
/// Constructs a MidiEvent from a BinaryStream
/// </summary>
/// <param name="reader">The binary stream of MIDI data</param>
/// <param name="previous">The previous MIDI event (pass null for first event)</param>
/// <returns>A new MidiEvent</returns>
public static MIDIEvent ReadNextEvent(BinaryReader reader, MIDIEvent previous)
{
int deltaTime = ReadVariableLengthInt(reader);
MIDICommandCodes commandCode;
int channel = 1;
byte nextByte = reader.ReadByte();
if ((nextByte & 0x80) == 0)
{
// a running command - command & channel are same as previous
commandCode = previous.CommandCode;
channel = previous.Channel;
reader.BaseStream.Position--; // need to push this back
}
else
{
if ((nextByte & 0xF0) == 0xF0)
{
// both bytes are used for command code in this case
commandCode = (MIDICommandCodes)nextByte;
}
else
{
commandCode = (MIDICommandCodes)(nextByte & 0xF0);
channel = (nextByte & 0x0F) + 1;
}
}
MIDIEvent midiEvent;
switch (commandCode)
{
case MIDICommandCodes.NoteOn:
midiEvent = NoteOnEvent.ReadNoteEvent(reader);
break;
case MIDICommandCodes.NoteOff:
case MIDICommandCodes.KeyAfterTouch:
midiEvent = NoteEvent.ReadNoteEvent(reader);
break;
case MIDICommandCodes.ControlChange:
midiEvent = ControlChangeEvent.ReadControlChangeEvent(reader);
break;
case MIDICommandCodes.PatchChange:
midiEvent = PatchChangeEvent.ReadPatchChangeEvent(reader);
break;
case MIDICommandCodes.ChannelAfterTouch:
midiEvent = ChannelAfterTouchEvent.ReadChannelAfterTouchEvent(reader);
break;
case MIDICommandCodes.PitchWheelChange:
midiEvent = PitchWheelChangeEvent.ReadPitchWheelChangeEvent(reader);
break;
case MIDICommandCodes.TimingClock:
case MIDICommandCodes.StartSequence:
case MIDICommandCodes.ContinueSequence:
case MIDICommandCodes.StopSequence:
midiEvent = new MIDIEvent();
break;
case MIDICommandCodes.Sysex:
midiEvent = SysexEvent.ReadSysexEvent(reader);
break;
case MIDICommandCodes.MetaEvent:
midiEvent = MetaEvent.ReadMetaEvent(reader);
break;
default:
throw new FormatException($"Unsupported MIDI Command Code {(byte)commandCode:X2}");
}
midiEvent.Channel = channel;
midiEvent.DeltaTime = deltaTime;
midiEvent.CommandCode = commandCode;
return midiEvent;
}
public void AddEvent(MIDIEvent midiEvent)
{
// If MIDI event is a note off event, pair it with the corresponding note on event
if(midiEvent is NoteEvent)
{
NoteEvent noteEvent = (NoteEvent)midiEvent;
if((noteEvent.CommandCode == MIDICommandCodes.NoteOff) ||
(noteEvent.CommandCode == MIDICommandCodes.NoteOn && noteEvent.Velocity <= 0))
{
PairWithNoteOnEvent(noteEvent);
}
}
// Add event to the proper list
if (midiEvent is ChannelAfterTouchEvent)
{
_track.ChannelAfterTouchEvents.Add((ChannelAfterTouchEvent)midiEvent);
}
else if (midiEvent is ControlChangeEvent)
{
_track.ControlChangeEvents.Add((ControlChangeEvent)midiEvent);
}
else if (midiEvent is KeySignatureEvent)
{
_track.KeySignatureEvents.Add((KeySignatureEvent)midiEvent);
}
else if (midiEvent is NoteOnEvent)
{
_track.NoteOnEvents.Add((NoteOnEvent)midiEvent);
_outstandingNoteOnEvents.Add((NoteOnEvent)midiEvent);
}
else if (midiEvent is PatchChangeEvent)
{
_track.PatchChangeEvents.Add((PatchChangeEvent)midiEvent);
}
else if (midiEvent is PitchWheelChangeEvent)
{
_track.PitchWheelChangeEvents.Add((PitchWheelChangeEvent)midiEvent);
}
else if (midiEvent is SequencerSpecificEvent)
{
_track.SequencerSpecificEvents.Add((SequencerSpecificEvent)midiEvent);
}
else if (midiEvent is SmpteOffsetEvent)
{
_track.SmpteOffsetEvents.Add((SmpteOffsetEvent)midiEvent);
}
else if (midiEvent is SysexEvent)
{
_track.SysexEvents.Add((SysexEvent)midiEvent);
}
else if (midiEvent is TempoEvent)
{
_track.TempoEvents.Add((TempoEvent)midiEvent);
}
else if (midiEvent is TextEvent)
{
_track.TextEvents.Add((TextEvent)midiEvent);
}
else if (midiEvent is TimeSignatureEvent)
{
_track.TimeSignatureEvents.Add((TimeSignatureEvent)midiEvent);
}
else if (midiEvent is TrackSequenceNumberEvent)
{
_track.TrackSequenceNumberEvents.Add((TrackSequenceNumberEvent)midiEvent);
}
}
