private static MidiTrack ReadTrack(BinaryReader reader)
{
List <byte> instList = new List <byte>();
List <byte> drumList = new List <byte>();
List <MidiEvent> eventList = new List <MidiEvent>();
int channelList = 0;
int noteOnCount = 0;
int totalTime = 0;
while (!new string(IOHelper.Read8BitChars(reader, 4)).Equals("MTrk"))
{
int length = BigEndianHelper.ReadInt32(reader);
while (length > 0)
{
length--;
reader.ReadByte();
}
}
long endPosition = BigEndianHelper.ReadInt32(reader) + reader.BaseStream.Position;
byte prevStatus = 0;
while (reader.BaseStream.Position < endPosition)
{
int delta = ReadVariableLength(reader);
totalTime += delta;
byte status = reader.ReadByte();
if (status >= 0x80 && status <= 0xEF)
{//voice message
prevStatus = status;
eventList.Add(ReadVoiceMessage(reader, delta, status, reader.ReadByte()));
TrackVoiceStats(eventList[eventList.Count - 1], instList, drumList, ref channelList, ref noteOnCount);
}
else if (status >= 0xF0 && status <= 0xF7)
{//system common message
prevStatus = 0;
eventList.Add(ReadSystemCommonMessage(reader, delta, status));
}
else if (status >= 0xF8 && status <= 0xFF)
{//realtime message
eventList.Add(ReadRealTimeMessage(reader, delta, status));
}
else
{ //data bytes
if (prevStatus == 0)
{ //if no running status continue to next status byte
while ((status & 0x80) != 0x80)
{
status = reader.ReadByte();
}
if (status >= 0x80 && status <= 0xEF)
{//voice message
prevStatus = status;
eventList.Add(ReadVoiceMessage(reader, delta, status, reader.ReadByte()));
TrackVoiceStats(eventList[eventList.Count - 1], instList, drumList, ref channelList, ref noteOnCount);
}
else if (status >= 0xF0 && status <= 0xF7)
{//system common message
eventList.Add(ReadSystemCommonMessage(reader, delta, status));
}
else if (status >= 0xF8 && status <= 0xFF)
{//realtime message
eventList.Add(ReadRealTimeMessage(reader, delta, status));
}
}
else
{//otherwise apply running status
eventList.Add(ReadVoiceMessage(reader, delta, prevStatus, status));
TrackVoiceStats(eventList[eventList.Count - 1], instList, drumList, ref channelList, ref noteOnCount);
}
}
}
if (reader.BaseStream.Position != endPosition)
{
throw new Exception("The track length was invalid for the current MTrk chunk.");
}
if (((channelList >> MidiHelper.DrumChannel) & 1) == 1)
{
if (!drumList.Contains(0))
{
drumList.Add(0);
}
}
else
{
if (!instList.Contains(0))
{
instList.Add(0);
}
}
MidiTrack track = new MidiTrack(instList.ToArray(), drumList.ToArray(), eventList.ToArray());
track.NoteOnCount = noteOnCount;
track.EndTime = totalTime;
track.ActiveChannels = channelList;
return(track);
}
private static MidiTrack ReadTrack(BinaryReader reader)
{
List<byte> instList = new List<byte>();
List<byte> drumList = new List<byte>();
List<MidiEvent> eventList = new List<MidiEvent>();
int channelList = 0;
int noteOnCount = 0;
int totalTime = 0;
while (!new string(IOHelper.Read8BitChars(reader, 4)).Equals("MTrk"))
{
int length = BigEndianHelper.ReadInt32(reader);
while (length > 0)
{
length--;
reader.ReadByte();
}
}
long endPosition = BigEndianHelper.ReadInt32(reader) + reader.BaseStream.Position;
byte prevStatus = 0;
while (reader.BaseStream.Position < endPosition)
{
int delta = ReadVariableLength(reader);
totalTime += delta;
byte status = reader.ReadByte();
if (status >= 0x80 && status <= 0xEF)
{//voice message
prevStatus = status;
eventList.Add(ReadVoiceMessage(reader, delta, status, reader.ReadByte()));
TrackVoiceStats(eventList[eventList.Count - 1], instList, drumList, ref channelList, ref noteOnCount);
}
else if (status >= 0xF0 && status <= 0xF7)
{//system common message
prevStatus = 0;
eventList.Add(ReadSystemCommonMessage(reader, delta, status));
}
else if (status >= 0xF8 && status <= 0xFF)
{//realtime message
eventList.Add(ReadRealTimeMessage(reader, delta, status));
}
else
{//data bytes
if (prevStatus == 0)
{//if no running status continue to next status byte
while ((status & 0x80) != 0x80)
status = reader.ReadByte();
if (status >= 0x80 && status <= 0xEF)
{//voice message
prevStatus = status;
eventList.Add(ReadVoiceMessage(reader, delta, status, reader.ReadByte()));
TrackVoiceStats(eventList[eventList.Count - 1], instList, drumList, ref channelList, ref noteOnCount);
}
else if (status >= 0xF0 && status <= 0xF7)
{//system common message
eventList.Add(ReadSystemCommonMessage(reader, delta, status));
}
else if (status >= 0xF8 && status <= 0xFF)
{//realtime message
eventList.Add(ReadRealTimeMessage(reader, delta, status));
}
}
else
{//otherwise apply running status
eventList.Add(ReadVoiceMessage(reader, delta, prevStatus, status));
TrackVoiceStats(eventList[eventList.Count - 1], instList, drumList, ref channelList, ref noteOnCount);
}
}
}
if (reader.BaseStream.Position != endPosition)
throw new Exception("The track length was invalid for the current MTrk chunk.");
if (((channelList >> MidiHelper.DrumChannel) & 1) == 1)
{
if(!drumList.Contains(0))
drumList.Add(0);
}
else
{
if(!instList.Contains(0))
instList.Add(0);
}
MidiTrack track = new MidiTrack(instList.ToArray(), drumList.ToArray(), eventList.ToArray());
track.NoteOnCount = noteOnCount;
track.EndTime = totalTime;
track.ActiveChannels = channelList;
return track;
}
private MidiTrack MergeTracks()
{
int eventCount = 0;
int notesPlayed = 0;
int activeChannels = 0;
List<byte> programsUsed = new List<byte>();
List<byte> drumprogramsUsed = new List<byte>();
//Loop to get track info
for (int x = 0; x < mTracks.Length; x++)
{
eventCount += mTracks[x].MidiEvents.Length;
notesPlayed += mTracks[x].NoteOnCount;
foreach (byte p in mTracks[x].Instruments)
{
if (!programsUsed.Contains(p))
programsUsed.Add(p);
}
foreach (byte p in mTracks[x].DrumInstruments)
{
if (!drumprogramsUsed.Contains(p))
drumprogramsUsed.Add(p);
}
activeChannels |= mTracks[x].ActiveChannels;
}
MidiTrack track = new MidiTrack(programsUsed.ToArray(), drumprogramsUsed.ToArray(), new MidiEvent[eventCount]);
track.NoteOnCount = notesPlayed;
track.ActiveChannels = activeChannels;
return track;
}
private void LoadStream(BinaryReader reader)
{
if (!FindHead(reader, 500))
throw new Exception("Invalid midi file : MThd chunk could not be found.");
ReadHeader(reader);
try
{
for (int x = 0; x < mTracks.Length; x++)
{
mTracks[x] = ReadTrack(reader);
}
}
catch(EndOfStreamException ex)
{
System.Diagnostics.Debug.WriteLine(ex.Message + "\nWarning: the midi file may not have one or more invalid tracks.");
byte[] emptyByte = new byte[0];
MidiEvent[] emptyEvents = new MidiEvent[0];
for (int x = 0; x < mTracks.Length; x++)
{
if (mTracks[x] == null)
mTracks[x] = new MidiTrack(emptyByte, emptyByte, emptyEvents);
}
}
}
