private void DefineMetaEvent(MidiEvent mEvent)
{
string result;
mEvent.EventFlag = MUtil.MetaEvent;
mEvent.MetaEvent = file.ReadByte();
mEvent.MetaLength = file.ReadVarlen();
mEvent.Value = file.ReadBytes(mEvent.MetaLength);
mEvent.Text = "ME ";//"" + EVENT_TYPE.MetaEvent; //+" " + mEvent.MetaEvent;
mEvent.Meta = ((META_EVENT)mEvent.MetaEvent);
result = string.Empty;
switch ((META_EVENT)mEvent.MetaEvent)
{
case META_EVENT.Copyright:
result = " Copyright " + System.Text.Encoding.UTF8.GetString(mEvent.Value);
break;
case META_EVENT.CuePoint:
result = " CuePoint " + System.Text.Encoding.UTF8.GetString(mEvent.Value);
break;
case META_EVENT.DeviceName:
result = " DeviceName " + System.Text.Encoding.UTF8.GetString(mEvent.Value);
break;
case META_EVENT.EndOfTrack:
result = " End of track ";
break;
case META_EVENT.Instrument:
result = " Instrument " + System.Text.Encoding.UTF8.GetString(mEvent.Value);
break;
case META_EVENT.KeySignature:
result += " KeySignature : " + MUtil.TranslateKeySignature(mEvent.Value);
break;
case META_EVENT.Lyric:
result = " Lyric " + System.Text.Encoding.UTF8.GetString(mEvent.Value);
break;
case META_EVENT.Marker:
result = " Marker " + System.Text.Encoding.UTF8.GetString(mEvent.Value);
break;
case META_EVENT.MIDIChannelPrefix:
byte channel = mEvent.Value[0];
result = " MIDIChannelPrefix: " + channel;
break;
case META_EVENT.MIDIPort:
byte port = mEvent.Value[0];
result = " MIDIPort: " + port;
break;
case META_EVENT.ProgramName:
result = " ProgramName " + System.Text.Encoding.UTF8.GetString(mEvent.Value);
break;
case META_EVENT.Sequence:
result = " Sequence " + System.Text.Encoding.UTF8.GetString(mEvent.Value);
break;
case META_EVENT.SequenceName:
result = " SequenceName " + System.Text.Encoding.UTF8.GetString(mEvent.Value);
break;
case META_EVENT.SequencerSpecificEvent:
result = " SequencerSpecific " + System.Text.Encoding.UTF8.GetString(mEvent.Value);
break;
case META_EVENT.SMPTEOffset:
result = " SMPTEOffset " + System.Text.Encoding.UTF8.GetString(mEvent.Value);
break;
case META_EVENT.Tempo:
result = SetMetaEventTempo(mEvent);
break;
case META_EVENT.Text:
result = " Text " + System.Text.Encoding.UTF8.GetString(mEvent.Value);
break;
case META_EVENT.TimeSignature:
result = " TimeSignature " + SetMetaEventTimeSignature(mEvent);
break;
}
mEvent.Text += result;
}
/// <summary>
/// Parse a single Midi track into a list of MidiEvents.
/// Entering this function, the file offset should be at the start of the MTrk header.
/// Upon exiting, the file offset should be at the
/// start of the next MTrk header.
/// </summary>
/// <returns></returns>
private List <MidiEvent> ReadTrackEvents()
{
List <MidiEvent> result = new List <MidiEvent>();
int starttime = 0;
int eventflag;
int tracklength;
int trackend;
string id = file.ReadAscii(4);
if (id != "MTrk")
{
throw new MidiException("Bad MTrk header", file.GetOffset() - 4);
}
tracklength = file.ReadInt();
trackend = tracklength + file.GetOffset();
eventflag = 0;
while (file.GetOffset() < trackend)
{
// If the midi file is truncated here, we can still recover.
// Just return what we've parsed so far.
int startoffset, deltatime, channel;
byte peekevent;
MidiEvent mEvent;
try
{
startoffset = file.GetOffset();
deltatime = file.ReadVarlen();
starttime += deltatime;
peekevent = file.Peek();
}
catch (MidiException)
{
return(result);
}
mEvent = new MidiEvent();
mEvent.DeltaTime = deltatime;
mEvent.StartTime = starttime;
result.Add(mEvent);
if (peekevent >= MUtil.EventNoteOff)
{
mEvent.HasEventflag = true;
eventflag = file.ReadByte();
}
channel = 0;
if (eventflag < byte.MaxValue)
{
channel = eventflag % 16;
}
mEvent.EventFlag = (byte)(eventflag - channel);
switch ((EVENT_TYPE)mEvent.EventFlag)
{
case EVENT_TYPE.NoteOn:
mEvent.Channel = (byte)(channel);
mEvent.Notenumber = file.ReadByte();
mEvent.Volume = file.ReadByte();
if (mEvent.Volume > 0)
{
mEvent.Text = "ON Ch: " + channel + " key: " + mEvent.Notenumber + " vel: " + mEvent.Volume;
mEvent.Type = EVENT_TYPE.NoteOn;
}
else
{
mEvent.EventFlag = (byte)(128);
mEvent.Text = "OFF Ch: " + channel + " key: " + mEvent.Notenumber + " vel: " + mEvent.Volume;
mEvent.Type = EVENT_TYPE.NoteOff;
}
break;
case EVENT_TYPE.NoteOff:
mEvent.Channel = (byte)(channel);
mEvent.Notenumber = file.ReadByte();
mEvent.Volume = file.ReadByte();
mEvent.Text = "OFF Ch: " + channel + " key: " + mEvent.Notenumber + " vel: " + mEvent.Volume;
mEvent.Type = ((EVENT_TYPE)mEvent.EventFlag);
break;
case EVENT_TYPE.ChannelAfterTouch:
mEvent.Channel = (byte)(channel);
mEvent.ChanPressure = file.ReadByte();
mEvent.Text = EVENT_TYPE.ChannelAfterTouch + " Ch: " + channel + " pressure: " + mEvent.ChanPressure;
mEvent.Type = ((EVENT_TYPE)mEvent.EventFlag);
break;
case EVENT_TYPE.ControlChange:
mEvent.Channel = (byte)(channel);
mEvent.ControlNum = file.ReadByte();
mEvent.ControlValue = file.ReadByte();
mEvent.Text = "CC Ch: " + channel + " C: " + ((CC)(mEvent.ControlNum)).ToString() + " value: " + mEvent.ControlValue;
mEvent.Type = ((EVENT_TYPE)mEvent.EventFlag);
break;
case EVENT_TYPE.KeyPressure:
mEvent.Channel = (byte)(channel);
mEvent.Notenumber = file.ReadByte();
mEvent.KeyPressure = file.ReadByte();
mEvent.Text = EVENT_TYPE.KeyPressure + " Ch: " + channel + " note: " + mEvent.Notenumber + " pressure: " + mEvent.KeyPressure;
mEvent.Type = ((EVENT_TYPE)mEvent.EventFlag);
break;
case EVENT_TYPE.PitchBend:
mEvent.Channel = (byte)(channel);
mEvent.PitchBend = file.ReadShort();
mEvent.Text = EVENT_TYPE.PitchBend + " Ch: " + channel + " PitchBend: " + mEvent.PitchBend;
mEvent.Type = ((EVENT_TYPE)mEvent.EventFlag);
break;
case EVENT_TYPE.ProgramChange:
mEvent.Channel = (byte)(channel);
mEvent.Instrument = file.ReadByte();
mEvent.Text = "PC Ch: " + channel + " : " + (INSTRUMENT)mEvent.Instrument;
mEvent.Type = ((EVENT_TYPE)mEvent.EventFlag);
break;
case EVENT_TYPE.SysexEvent1:
mEvent.MetaLength = file.ReadVarlen();
mEvent.Value = file.ReadBytes(mEvent.MetaLength);
string val = string.Empty;
for (int i = 0; i < mEvent.Value.Length; i++)
{
val += mEvent.Value[i] + " ";
}
mEvent.Text = EVENT_TYPE.SysexEvent1 + " length: " + mEvent.MetaLength + " value: " + val;
mEvent.Type = ((EVENT_TYPE)mEvent.EventFlag);
break;
case EVENT_TYPE.SysexEvent2:
mEvent.MetaLength = file.ReadVarlen();
mEvent.Value = file.ReadBytes(mEvent.MetaLength);
mEvent.Text = EVENT_TYPE.SysexEvent2 + " length: " + mEvent.MetaLength + " value: " + mEvent.Value;
mEvent.Type = ((EVENT_TYPE)mEvent.EventFlag);
break;
case EVENT_TYPE.MetaEvent:
DefineMetaEvent(mEvent);
mEvent.Type = ((EVENT_TYPE)mEvent.EventFlag);
break;
default:
throw new MidiException("Unknown event " + mEvent.EventFlag, file.GetOffset() - 1);
}
}
return(result);
}
