//--Private Methods
private void loadStream(Stream stream)
{
combinedTrack = null;
byte[] tmp = new byte[4];
stream.Read(tmp, 0, 4);
if (UTF8Encoding.UTF8.GetString(tmp, 0, tmp.Length) != "MThd")
{
throw new Exception("Not a valid midi file!");
}
mheader = new MidiHeader();
//Read header length then discard, since the header's length always 6
stream.Read(tmp, 0, 4);
//Array.Reverse(tmp);
//int headerLength = BitConverter.ToInt32(tmp, 0);
//Read midi format
tmp = new byte[2];
stream.Read(tmp, 0, 2);
Array.Reverse(tmp);
mheader.setMidiFormat(BitConverter.ToInt16(tmp, 0));
//Read Track Count
stream.Read(tmp, 0, 2);
Array.Reverse(tmp);
int trackCount = BitConverter.ToInt16(tmp, 0);
tracks = new MidiTrack[trackCount];
//Read Delta time
stream.Read(tmp, 0, 2);
Array.Reverse(tmp);
int delta = BitConverter.ToInt16(tmp, 0);
mheader.deltaTicksPerQuarterNote = (delta & 0x7FFF);
//Time Format
mheader.TimeFormat = ((delta & 0x8000) > 0) ? MidiHelper.MidiTimeFormat.FamesPerSecond : MidiHelper.MidiTimeFormat.TicksPerBeat;
//Begin Reading Each Track
for (int x = 0; x < trackCount; x++)
{
List <byte> Programs = new List <byte>();
List <byte> DrumPrograms = new List <byte>();
List <MidiEvent> midiEvList = new List <MidiEvent>();
tracks[x] = new MidiTrack();
//assume the track uses program at 0 in case no program changes are used
Programs.Add(0);
DrumPrograms.Add(0);
tmp = new byte[4];
//is valid MIDI track?
stream.Read(tmp, 0, 4);
if (UTF8Encoding.UTF8.GetString(tmp, 0, tmp.Length) != "MTrk")
{
throw new Exception("Invalid track!");
}
//read track's length in byte
stream.Read(tmp, 0, 4);
Array.Reverse(tmp); //Reverse the bytes
int TrackLength = BitConverter.ToInt32(tmp, 0);
//Read The Rest of The Track
tmp = new byte[TrackLength];
stream.Read(tmp, 0, TrackLength);
//read index
int index = 0;
byte prevByte = 0;
int prevChan = 0;
ulong lastDeltaTimeFromStart = 0;
while (index < tmp.Length)
{
UInt16 numofbytes = 0;
//UInt32 ScrmbledDta = BitConverter.ToUInt32(tmp, index);
MidiEvent MEv = new MidiEvent();
//delta time
MEv.deltaTime = MEv.sampleTime = ReadDeltaTime(tmp, index, ref numofbytes);
//update delta time from start
MEv.deltaTimeFromStart = lastDeltaTimeFromStart += MEv.deltaTime;
lastDeltaTimeFromStart = MEv.deltaTimeFromStart;
//MEv.sampleTime = GetTime(ScrmbledDta, ref numofbytes);
//index += 4 - (4 - numofbytes);
// deduce bytes used when reading delta time
index += numofbytes;
byte statusByte = tmp[index];
int CHANNEL = GetChannel(statusByte);
if (statusByte < 0x80)
{
statusByte = prevByte;
CHANNEL = prevChan;
index--;
}
if (statusByte != 0xFF)
{
statusByte &= 0xF0;
}
prevByte = statusByte;
prevChan = CHANNEL;
switch (statusByte)
{
case 0x80: {
MEv.midiChannelEvent = MidiHelper.MidiChannelEvent.Note_Off;
++index;
MEv.channel = (byte)CHANNEL;
MEv.Parameters[0] = MEv.channel;
MEv.parameter1 = tmp[index++];
MEv.parameter2 = tmp[index++];
MEv.Parameters[1] = MEv.parameter1;
MEv.Parameters[2] = MEv.parameter2;
}
break;
case 0x90: {
MEv.midiChannelEvent = MidiHelper.MidiChannelEvent.Note_On;
++index;
MEv.channel = (byte)CHANNEL;
MEv.Parameters[0] = MEv.channel;
MEv.parameter1 = tmp[index++];
MEv.parameter2 = tmp[index++];
MEv.Parameters[1] = MEv.parameter1;
MEv.Parameters[2] = MEv.parameter2;
if (MEv.parameter2 == 0x00) //Setting velocity to 0 is actually just turning the note off.
{
MEv.midiChannelEvent = MidiHelper.MidiChannelEvent.Note_Off;
}
tracks[x].notesPlayed++;
}
break;
case 0xA0: {
MEv.midiChannelEvent = MidiHelper.MidiChannelEvent.Note_Aftertouch;
MEv.channel = (byte)CHANNEL;
MEv.Parameters[0] = MEv.channel;
++index;
MEv.parameter1 = tmp[++index]; //note number
MEv.parameter2 = tmp[++index]; //Amount
}
break;
case 0xB0: {
MEv.midiChannelEvent = MidiHelper.MidiChannelEvent.Controller;
MEv.channel = (byte)CHANNEL;
MEv.Parameters[0] = MEv.channel;
++index;
MEv.parameter1 = tmp[index++]; //type
MEv.parameter2 = tmp[index++]; //value
MEv.Parameters[1] = MEv.parameter1;
MEv.Parameters[2] = MEv.parameter2;
}
break;
case 0xC0: {
MEv.midiChannelEvent = MidiHelper.MidiChannelEvent.Program_Change;
MEv.channel = (byte)CHANNEL;
MEv.Parameters[0] = MEv.channel;
++index;
MEv.parameter1 = tmp[index++];
MEv.Parameters[1] = MEv.parameter1;
//record which programs are used by the track
if (MEv.channel != 9)
{
if (Programs.Contains(MEv.parameter1) == false)
{
Programs.Add(MEv.parameter1);
}
}
else
{
if (DrumPrograms.Contains(MEv.parameter1) == false)
{
DrumPrograms.Add(MEv.parameter1);
}
}
}
break;
case 0xD0: {
MEv.midiChannelEvent = MidiHelper.MidiChannelEvent.Channel_Aftertouch;
MEv.channel = (byte)CHANNEL;
MEv.Parameters[0] = MEv.channel;
++index;
//Amount
MEv.parameter1 = tmp[++index];
}
break;
case 0xE0: {
MEv.midiChannelEvent = MidiHelper.MidiChannelEvent.Pitch_Bend;
MEv.channel = (byte)CHANNEL;
MEv.Parameters[0] = MEv.channel;
++index;
MEv.parameter1 = tmp[++index];
MEv.parameter2 = tmp[++index];
ushort s = (ushort)MEv.parameter1;
s <<= 7;
s |= (ushort)MEv.parameter2;
MEv.Parameters[1] = ((double)s - 8192.0) / 8192.0;
}
break;
case 0xFF:
statusByte = tmp[++index];
switch (statusByte)
{
case 0x00:
MEv.midiMetaEvent = MidiHelper.MidiMetaEvent.Sequence_Number; ++index;
break;
case 0x01:
MEv.midiMetaEvent = MidiHelper.MidiMetaEvent.Text_Event; ++index;
//Get the length of the string
MEv.parameter1 = tmp[index++];
MEv.Parameters[0] = MEv.parameter1;
//Set the string in the parameter list
MEv.Parameters[1] = UTF8Encoding.UTF8.GetString(tmp, index, ((int)tmp[index - 1])); index += (int)tmp[index - 1];
break;
case 0x02:
MEv.midiMetaEvent = MidiHelper.MidiMetaEvent.Copyright_Notice; ++index;
//Get the length of the string
MEv.parameter1 = tmp[index++];
MEv.Parameters[0] = MEv.parameter1;
//Set the string in the parameter list
MEv.Parameters[1] = UTF8Encoding.UTF8.GetString(tmp, index, ((int)tmp[index - 1])); index += (int)tmp[index - 1];
break;
case 0x03:
MEv.midiMetaEvent = MidiHelper.MidiMetaEvent.Sequence_Or_Track_Name; ++index;
//Get the length of the string
MEv.parameter1 = tmp[index++];
MEv.Parameters[0] = MEv.parameter1;
//Set the string in the parameter list and also the name of this track
MEv.Parameters[1] = tracks[x].trackName = UTF8Encoding.UTF8.GetString(tmp, index, ((int)tmp[index - 1])); index += (int)tmp[index - 1];
break;
case 0x04:
MEv.midiMetaEvent = MidiHelper.MidiMetaEvent.Instrument_Name; ++index;
//Set the instrument name
MEv.Parameters[0] = UTF8Encoding.UTF8.GetString(tmp, index + 1, (int)tmp[index]);
index += (int)tmp[index] + 1;
break;
case 0x05:
MEv.midiMetaEvent = MidiHelper.MidiMetaEvent.Lyric_Text; ++index;
//Set the lyric string
MEv.Parameters[0] = tracks[x].lyricText = UTF8Encoding.UTF8.GetString(tmp, index + 1, (int)tmp[index]);
index += (int)tmp[index] + 1;
break;
case 0x06:
MEv.midiMetaEvent = MidiHelper.MidiMetaEvent.Marker_Text; ++index;
//Set the marker
MEv.Parameters[0] = tracks[x].markerText = UTF8Encoding.UTF8.GetString(tmp, index + 1, (int)tmp[index]);
index += (int)tmp[index] + 1;
break;
case 0x07:
MEv.midiMetaEvent = MidiHelper.MidiMetaEvent.Cue_Point; ++index;
//Set the cue point
MEv.Parameters[0] = UTF8Encoding.UTF8.GetString(tmp, index + 1, (int)tmp[index]);
index += (int)tmp[index] + 1;
break;
case 0x20:
MEv.midiMetaEvent = MidiHelper.MidiMetaEvent.Midi_Channel_Prefix_Assignment; index++;
//Get the length of the data
MEv.parameter1 = tmp[index++];
MEv.Parameters[0] = MEv.parameter1;
//Set the string in the parameter list
MEv.Parameters[1] = tmp[index++];
break;
case 0x2F:
MEv.midiMetaEvent = MidiHelper.MidiMetaEvent.End_of_Track;
index += 2;
break;
case 0x51:
MEv.midiMetaEvent = MidiHelper.MidiMetaEvent.Tempo; ++index;
//Get the length of the data
MEv.Parameters[4] = tmp[index++];
//Put the data into an array
byte[] mS = new byte[4]; for (int i = 0; i < 3; i++)
{
mS[i + 1] = tmp[i + index];
}
index += 3;
//Put it into a readable format
byte[] mS2 = new byte[4]; for (int i = 0; i < 4; i++)
{
mS2[3 - i] = mS[i];
}
//Get the value from the array
UInt32 Val = BitConverter.ToUInt32(mS2, 0);
//Set the value
MEv.Parameters[0] = Val;
break;
case 0x54:
MEv.midiMetaEvent = MidiHelper.MidiMetaEvent.Smpte_Offset; ++index;
int v = tmp[index++];
if (v >= 4)
{
for (int i = 0; i < 4; i++)
{
MEv.Parameters[i] = tmp[index++];
}
}
else
{
for (int i = 0; i < v; i++)
{
MEv.Parameters[i] = tmp[index++];
}
}
for (int i = 4; i < v; i++)
{
index++;
}
break;
case 0x58:
MEv.midiMetaEvent = MidiHelper.MidiMetaEvent.Time_Signature; ++index;
int v1 = tmp[index++];
if (v1 >= 4)
{
for (int i = 0; i < 4; i++)
{
MEv.Parameters[i] = tmp[index++];
}
}
else
{
for (int i = 0; i < v1; i++)
{
MEv.Parameters[i] = tmp[index++];
}
}
for (int i = 4; i < v1; i++)
{
index++;
}
break;
case 0x59:
MEv.midiMetaEvent = MidiHelper.MidiMetaEvent.Key_Signature; ++index;
int v2 = tmp[index++];
if (v2 >= 4)
{
for (int i = 0; i < 4; i++)
{
MEv.Parameters[i] = tmp[index++];
}
}
else
{
for (int i = 0; i < v2; i++)
{
MEv.Parameters[i] = tmp[index++];
}
}
for (int i = 4; i < v2; i++)
{
index++;
}
break;
case 0x7F:
//Sequencer specific events
MEv.midiMetaEvent = MidiHelper.MidiMetaEvent.Sequencer_Specific_Event; ++index; //increment the indexer
//Get the length of the data
MEv.Parameters[4] = tmp[index++];
//Get the byte length
byte[] len = new byte[(byte)MEv.Parameters[4]];
//get the byte info
for (int i = 0; i < len.Length; i++)
{
len[i] = tmp[index++];
}
MEv.Parameters[0] = len;
break;
}
break;
//System exclusive
case 0xF0:
while (tmp[index] != 0xF7)
{
index++;
}
index++;
break;
}
midiEvList.Add(MEv);
//MEv.deltaTimeFromStart = tracks[x].totalTime;
tracks[x].totalTime = tracks[x].totalTime + MEv.sampleTime;
}
tracks[x].programs = Programs.ToArray();
tracks[x].drumPrograms = DrumPrograms.ToArray();
tracks[x].midiEvents = midiEvList.ToArray();
}
}
public void CombineTracks()
{
if (tracks.Length < 2)
{
return;
}
int total_eventCount = 0;
UInt64 total_notesPlayed = 0;
List <byte> programsUsed = new List <byte>();
List <byte> DrumprogramsUsed = new List <byte>();
//Loop to get track info
for (int x = 0; x < tracks.Length; x++)
{
total_eventCount = total_eventCount + tracks[x].midiEvents.Length;
total_notesPlayed = total_notesPlayed + tracks[x].notesPlayed;
for (int x2 = 0; x2 < tracks[x].programs.Length; x2++)
{
if (programsUsed.Contains(tracks[x].programs[x2]) == false)
{
programsUsed.Add(tracks[x].programs[x2]);
}
}
for (int x2 = 0; x2 < tracks[x].drumPrograms.Length; x2++)
{
if (DrumprogramsUsed.Contains(tracks[x].drumPrograms[x2]) == false)
{
DrumprogramsUsed.Add(tracks[x].drumPrograms[x2]);
}
}
}
//Now process the midi events
Dictionary <uint, LinkedList <MidiEvent> > orderedTracks = new Dictionary <uint, LinkedList <MidiEvent> >(total_eventCount);
for (int x = 0; x < tracks.Length; x++)
{
uint currentDeltaTime = 0;
MidiEvent[] trackMidiEvents = new MidiEvent[tracks[x].midiEvents.Length];
tracks[x].midiEvents.CopyTo(trackMidiEvents, 0);
for (int x2 = 0; x2 < trackMidiEvents.Length; x2++)
{
currentDeltaTime = currentDeltaTime + trackMidiEvents[x2].sampleTime;
trackMidiEvents[x2].sampleTime = currentDeltaTime;
if (orderedTracks.ContainsKey(trackMidiEvents[x2].sampleTime) == true)
{
orderedTracks[trackMidiEvents[x2].sampleTime].AddLast(trackMidiEvents[x2]);
}
else
{
LinkedList <MidiEvent> tmplist = new LinkedList <MidiEvent>();
tmplist.AddLast(trackMidiEvents[x2]);
orderedTracks.Add(trackMidiEvents[x2].sampleTime, tmplist);
}
}
}
//Sort the Dictionary
uint[] keys = new uint[orderedTracks.Keys.Count];
orderedTracks.Keys.CopyTo(keys, 0);
Array.Sort(keys);
//mirror the events to appropriate timeline
LinkedList <MidiEvent>[] trackEvents = new LinkedList <MidiEvent> [orderedTracks.Values.Count];
for (int x = 0; x < trackEvents.Length; x++)
{
trackEvents[x] = orderedTracks[keys[x]];
}
orderedTracks.Clear();
keys = null;
//separate combined tracks into a new one
combinedTrack = new MidiTrack();
combinedTrack.programs = programsUsed.ToArray();
combinedTrack.drumPrograms = DrumprogramsUsed.ToArray();
combinedTrack.midiEvents = new MidiEvent[total_eventCount];
uint PreviousDeltaTime = 0;
uint cc = 0;
for (int x = 0; x < trackEvents.Length; x++)
{
LinkedListNode <MidiEvent> tmpN = trackEvents[x].First;
while (tmpN != null)
{
uint old1 = tmpN.Value.sampleTime;
tmpN.Value.sampleTime = (tmpN.Value.sampleTime - PreviousDeltaTime);
PreviousDeltaTime = old1;
combinedTrack.midiEvents[cc] = tmpN.Value;
combinedTrack.totalTime = combinedTrack.totalTime + (ulong)tmpN.Value.sampleTime;
tmpN = tmpN.Next;
cc++;
}
}
combinedTrack.notesPlayed = (uint)total_notesPlayed;
}
