public MidiTrack(byte[] instPrograms, byte[] drumPrograms, MidiEvent[] midiEvents)
{
this.instPrograms = instPrograms;
this.drumPrograms = drumPrograms;
this.midiEvents = midiEvents;
this.notesPlayed = 0;
this.totalTime = 0;
this.activeChannels = 0;
}
public void CombineTracks()
{
//create a new track of the appropriate size
MidiTrack finalTrack = MergeTracks();
MidiEvent[][] absevents = new MidiEvent[mTracks.Length][];
//we have to convert delta times to absolute delta times
for (int x = 0; x < absevents.Length; x++)
{
absevents[x] = new MidiEvent[mTracks[x].MidiEvents.Length];
for (int x2 = 0, totalDeltaTime = 0; x2 < absevents[x].Length; x2++)
{//create copies
absevents[x][x2] = mTracks[x].MidiEvents[x2];
totalDeltaTime += absevents[x][x2].DeltaTime;
absevents[x][x2].DeltaTime = totalDeltaTime;
}
}
//sort by absolute delta time also makes sure events occur in order of track and when they are recieved.
int eventcount = 0;
int delta = 0;
int nextdelta = int.MaxValue;
int[] counters = new int[absevents.Length];
while (eventcount < finalTrack.MidiEvents.Length)
{
for (int x = 0; x < absevents.Length; x++)
{
while (counters[x] < absevents[x].Length && absevents[x][counters[x]].DeltaTime == delta)
{
finalTrack.MidiEvents[eventcount] = absevents[x][counters[x]];
eventcount++;
counters[x]++;
}
if (counters[x] < absevents[x].Length && absevents[x][counters[x]].DeltaTime < nextdelta)
nextdelta = absevents[x][counters[x]].DeltaTime;
}
delta = nextdelta;
nextdelta = int.MaxValue;
}
//set total time
finalTrack.EndTime = finalTrack.MidiEvents[finalTrack.MidiEvents.Length - 1].DeltaTime;
//put back into regular delta time
for (int x = 0, deltadiff = 0; x < finalTrack.MidiEvents.Length; x++)
{
int oldtime = finalTrack.MidiEvents[x].DeltaTime;
finalTrack.MidiEvents[x].DeltaTime -= deltadiff;
deltadiff = oldtime;
}
this.mTracks = new MidiTrack[] { finalTrack };
this.mTrackFormat = TrackFormat.SingleTrack;
}
private static void TrackVoiceStats(MidiEvent midiEvent, List<byte> instList, List<byte> drumList, ref int channelList, ref int noteOnCount)
{
if (midiEvent.Command == 0x90) //note on
{
channelList |= 1 << midiEvent.Channel;
noteOnCount++;
}
else if (midiEvent.Command == 0xC0) //prog change
{
byte prog = (byte)midiEvent.Data1;
if (midiEvent.Channel == MidiHelper.DrumChannel && !drumList.Contains(prog))
{
drumList.Add(prog);
}
else if (!instList.Contains(prog))
{
instList.Add(prog);
}
}
}
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);
}
}
}
