// util functions
private static bool TrackIsOmitable(MidiTrack tr)
{
foreach (MidiEvent ev in tr.midiEvents)
{
if (ev is MetaMidiEvent)
{
MetaMidiEvent mev = ev as MetaMidiEvent;
if (mev.getMetaType() == MetaType.TempoSetting)
{
return(false);
}
else if (mev.getMetaType() == MetaType.TimeSignature)
{
return(false);
}
else if (mev.getMetaType() == MetaType.MarkerText)
{
return(false);
}
}
else if (ev is MessageMidiEvent)
{
MessageMidiEvent mev = ev as MessageMidiEvent;
if (mev.type == NormalType.NoteON)
{
return(false);
}
if (mev.type == NormalType.NoteOFF)
{
return(false);
}
}
}
return(true);
}
public static void Trim(MidiFile midi)
{
/******************
* removes empty tracks and redundant controller/voice events
*/
midi.midiTracks.RemoveAll(TrackIsOmitable);
foreach (MidiTrack tr in midi.midiTracks)
{
// int array for storing the last set values of the controller values
int[] controllerValues = new int[128];
for (int i = 0; i < controllerValues.Length; i++)
{
controllerValues[i] = -1;
}
int lastVoice = -1;
int lastPitchBendA = -1;
int lastPitchBendB = -1;
int lastTempo = -1;
for (int i = 0; i < tr.midiEvents.Count;)
{
if (tr.midiEvents[i] is MessageMidiEvent)
{
MessageMidiEvent mev = tr.midiEvents[i] as MessageMidiEvent;
if (mev.type == NormalType.Program)
{
if (mev.parameter1 == lastVoice)
{
tr.midiEvents.RemoveAt(i);
continue;
}
lastVoice = mev.parameter1;
}
else if (mev.type == NormalType.PitchBend)
{
if (mev.parameter1 == lastPitchBendA && mev.parameter2 == lastPitchBendB)
{
tr.midiEvents.RemoveAt(i);
continue;
}
lastPitchBendA = mev.parameter1;
lastPitchBendB = mev.parameter2;
}
else if (mev.type == NormalType.Controller)
{
if (controllerValues[mev.parameter1] == mev.parameter2)
{
tr.midiEvents.RemoveAt(i);
continue;
}
controllerValues[mev.parameter1] = mev.parameter2;
}
}
else if (tr.midiEvents[i] is MetaMidiEvent)
{
MetaMidiEvent mev = tr.midiEvents[i] as MetaMidiEvent;
if (mev.getMetaType() == MetaType.TempoSetting)
{
byte[] tempoBytes = mev.getEventData();
Debug.Assert(tempoBytes.Length == 6);
int us = (tempoBytes[3] << 16) | (tempoBytes[4] << 8) | tempoBytes[5];
if (lastTempo == us)
{
tr.midiEvents.RemoveAt(i);
continue;
}
lastTempo = us;
}
}
// only count up if the current event didn't get deleted
i++;
}
}
}
public static void InstrMap(MidiFile midi, string mapping)
{
/******************
* maps instruments and drums using a map
*/
byte[] instrMap = new byte[128];
for (int i = 0; i < instrMap.Length; i++)
{
instrMap[i] = (byte)i;
}
sbyte[] transposeMap = new sbyte[128];
byte[] drumMap = new byte[128];
for (int i = 0; i < drumMap.Length; i++)
{
drumMap[i] = (byte)i;
}
bool[] isDrum = new bool[128];
// parse mapping string
//
// format:
// drum=127,imap=53:70,imap=30:25,dmap=40:50,trans=50:-12
string[] cfg = mapping.Split(',');
for (int i = 0; i < cfg.Length; i++)
{
string[] parts = cfg[i].Split('=');
if (parts.Length != 2)
{
throw new Exception("Invalid mapping option: " + String.Join("=", parts));
}
switch (parts[0])
{
case "drum":
{
int drum = Convert.ToInt32(parts[1]);
if (drum < 0 || drum > 127)
{
throw new Exception("drum instrument number out of range: " + drum.ToString());
}
isDrum[drum] = true;
}
break;
case "imap":
{
string[] fromTo = parts[1].Split(':');
if (fromTo.Length != 2)
{
throw new Exception("Invalid instrument map: " + String.Join(":", fromTo));
}
int from = Convert.ToInt32(fromTo[0]);
if (from < 0 || from > 127)
{
throw new Exception("instrument 'from' out of range: " + from.ToString());
}
int to = Convert.ToInt32(fromTo[1]);
if (to < 0 || to > 127)
{
throw new Exception("instrument 'to' out of range: " + to.ToString());
}
instrMap[from] = (byte)to;
}
break;
case "dmap":
{
string[] fromTo = parts[1].Split(':');
if (fromTo.Length != 2)
{
throw new Exception("Invalid drum map: " + String.Join(":", fromTo));
}
int from = Convert.ToInt32(fromTo[0]);
if (from < 0 || from > 127)
{
throw new Exception("drum 'from' out of range: " + from.ToString());
}
int to = Convert.ToInt32(fromTo[1]);
if (to < 0 || to > 127)
{
throw new Exception("drum 'to' out of range: " + to.ToString());
}
drumMap[from] = (byte)to;
}
break;
case "trans":
{
string[] trans = parts[1].Split(':');
if (trans.Length != 2)
{
throw new Exception("Invalid Transpose: " + String.Join(":", trans));
}
int instr = Convert.ToInt32(trans[0]);
if (instr < 0 || instr > 127)
{
throw new Exception("Transpose instrument out of range: " + instr.ToString());
}
int shift = Convert.ToInt32(trans[1]);
if (shift < -128 || shift > 127)
{
throw new Exception("Transpose shift out of range: " + shift.ToString());
}
transposeMap[instr] = (sbyte)shift;
}
break;
default:
throw new Exception("Invalid mapping type: " + parts[0]);
}
}
// update events
foreach (MidiTrack trk in midi.midiTracks)
{
int curProg = -1;
foreach (MidiEvent ev in trk.midiEvents)
{
if (ev is MessageMidiEvent)
{
MessageMidiEvent mev = ev as MessageMidiEvent;
if (mev.type == NormalType.Program)
{
curProg = mev.parameter1;
mev.parameter1 = instrMap[mev.parameter1];
}
else if (mev.type == NormalType.NoteON || mev.type == NormalType.NoteOFF)
{
if (curProg != 0)
{
if (isDrum[curProg])
{
mev.parameter1 = drumMap[mev.parameter1];
}
else
{
mev.parameter1 = (byte)(mev.parameter1 + transposeMap[curProg]);
}
}
}
}
}
}
}
public static void FullMaximize(MidiFile midi)
{
/******************
* maximizes expression to peak level
*/
// get expression multipliers
int[] expPeak = new int[midi.midiTracks.Count];
int[] volPeak = new int[midi.midiTracks.Count];
int[] velPeak = new int[midi.midiTracks.Count];
for (int i = 0; i < midi.midiTracks.Count; i++)
{
expPeak[i] = -1;
volPeak[i] = -1;
velPeak[i] = -1;
}
int itrk = 0;
foreach (MidiTrack trk in midi.midiTracks)
{
foreach (MidiEvent ev in trk.midiEvents)
{
if (ev is MessageMidiEvent)
{
MessageMidiEvent mev = ev as MessageMidiEvent;
if (mev.type == NormalType.Controller && mev.parameter1 == 11 && mev.parameter2 > 0)
{
expPeak[itrk] = Math.Max(expPeak[itrk], mev.parameter2);
}
else if (mev.type == NormalType.Controller && mev.parameter1 == 7 && mev.parameter2 > 0)
{
volPeak[itrk] = Math.Max(volPeak[itrk], mev.parameter2);
}
else if (mev.type == NormalType.NoteON && mev.parameter2 > 0)
{
velPeak[itrk] = Math.Max(velPeak[itrk], mev.parameter2);
}
}
}
itrk++;
}
// update levels
itrk = 0;
foreach (MidiTrack trk in midi.midiTracks)
{
foreach (MidiEvent ev in trk.midiEvents)
{
if (ev is MessageMidiEvent)
{
MessageMidiEvent mev = ev as MessageMidiEvent;
if (mev.type == NormalType.Controller && mev.parameter1 == 11)
{
double newval = 127.0 / expPeak[itrk] * mev.parameter2;
newval = Math.Round(newval, MidpointRounding.AwayFromZero);
newval = Math.Min(127.0, newval);
newval = Math.Max(0.0, newval);
mev.parameter2 = (byte)newval;
}
else if (mev.type == NormalType.Controller && mev.parameter1 == 7)
{
double newval = 127.0 / volPeak[itrk] * mev.parameter2;
newval = Math.Round(newval, MidpointRounding.AwayFromZero);
newval = Math.Min(127.0, newval);
newval = Math.Max(0.0, newval);
mev.parameter2 = (byte)newval;
}
else if (mev.type == NormalType.NoteON && mev.parameter2 > 0)
{
double newval = 127.0 / velPeak[itrk] * mev.parameter2;
newval = Math.Round(newval, MidpointRounding.AwayFromZero);
newval = Math.Min(127.0, newval);
newval = Math.Max(0.0, newval);
mev.parameter2 = (byte)newval;
}
}
}
itrk++;
}
}
public static void Maximize(MidiFile midi)
{
/******************
* maximizes expression to peak level
*/
// get expression multipliers
int expPeak = -1;
int volPeak = -1;
int velPeak = -1;
foreach (MidiTrack trk in midi.midiTracks)
{
foreach (MidiEvent ev in trk.midiEvents)
{
if (ev is MessageMidiEvent)
{
MessageMidiEvent mev = ev as MessageMidiEvent;
if (mev.type == NormalType.Controller && mev.parameter1 == 11 && mev.parameter2 > 0)
{
expPeak = Math.Max(expPeak, mev.parameter2);
}
else if (mev.type == NormalType.Controller && mev.parameter1 == 7 && mev.parameter2 > 0)
{
volPeak = Math.Max(volPeak, mev.parameter2);
}
else if (mev.type == NormalType.NoteON && mev.parameter2 > 0)
{
velPeak = Math.Max(velPeak, mev.parameter2);
}
}
}
}
// update levels
foreach (MidiTrack trk in midi.midiTracks)
{
foreach (MidiEvent ev in trk.midiEvents)
{
if (ev is MessageMidiEvent)
{
MessageMidiEvent mev = ev as MessageMidiEvent;
if (mev.type == NormalType.Controller && mev.parameter1 == 11)
{
double newval = 127.0 / expPeak * mev.parameter2;
newval = Math.Round(newval, MidpointRounding.AwayFromZero);
newval = Math.Min(127.0, newval);
newval = Math.Max(0.0, newval);
mev.parameter2 = (byte)newval;
}
else if (mev.type == NormalType.Controller && mev.parameter1 == 7)
{
double newval = 127.0 / volPeak * mev.parameter2;
newval = Math.Round(newval, MidpointRounding.AwayFromZero);
newval = Math.Min(127.0, newval);
newval = Math.Max(0.0, newval);
mev.parameter2 = (byte)newval;
}
else if (mev.type == NormalType.NoteON && mev.parameter2 > 0)
{
double newval = 127.0 / velPeak * mev.parameter2;
newval = Math.Round(newval, MidpointRounding.AwayFromZero);
newval = Math.Min(127.0, newval);
newval = Math.Max(0.0, newval);
mev.parameter2 = (byte)newval;
}
}
}
}
}
