private void ReadHeader(IReadable input)
{
if (input.ReadInt32BE() != 6)
{
throw new Exception("Midi header is invalid.");
}
TrackFormat = (MidiTrackFormat)input.ReadInt16BE();
Tracks = new MidiTrack[input.ReadInt16BE()];
var div = input.ReadInt16BE();
Division = div & 0x7FFF;
TimingStandard = ((div & 0x8000) > 0) ? MidiTimeFormat.FramesPerSecond : MidiTimeFormat.TicksPerBeat;
}
private MidiTrack ReadTrack(IReadable input)
{
var instList = new FastList <Byte>();
var drumList = new FastList <Byte>();
var channelList = new FastList <Byte>();
var eventList = new FastList <MidiEvent>();
var noteOnCount = 0;
var totalTime = 0;
while (input.Read8BitChars(4) != "MTrk")
{
var length = input.ReadInt32BE();
while (length > 0)
{
length--;
input.ReadByte();
}
}
var endPosition = input.ReadInt32BE() + input.Position;
var prevStatus = 0;
while (input.Position < endPosition)
{
var delta = ReadVariableLength(input);
totalTime += delta;
var status = input.ReadByte();
if (status >= 0x80 && status <= 0xEF)
{//voice message
prevStatus = status;
eventList.Add(ReadVoiceMessage(input, delta, (byte)status, (byte)input.ReadByte()));
noteOnCount = TrackVoiceStats(eventList[eventList.Count - 1], instList, drumList, channelList, noteOnCount);
}
else if (status >= 0xF0 && status <= 0xF7)
{//system common message
prevStatus = 0;
eventList.Add(ReadSystemCommonMessage(input, delta, (byte)status));
}
else if (status >= 0xF8 && status <= 0xFF)
{//realtime message
eventList.Add(ReadRealTimeMessage(input, delta, (byte)status));
}
else
{ //data bytes
if (prevStatus == 0)
{ //if no running status continue to next status byte
while ((status & 0x80) != 0x80)
{
status = input.ReadByte();
}
if (status >= 0x80 && status <= 0xEF)
{//voice message
prevStatus = status;
eventList.Add(ReadVoiceMessage(input, delta, (byte)status, (byte)input.ReadByte()));
noteOnCount = TrackVoiceStats(eventList[eventList.Count - 1], instList, drumList, channelList, noteOnCount);
}
else if (status >= 0xF0 && status <= 0xF7)
{//system common message
eventList.Add(ReadSystemCommonMessage(input, delta, (byte)status));
}
else if (status >= 0xF8 && status <= 0xFF)
{//realtime message
eventList.Add(ReadRealTimeMessage(input, delta, (byte)status));
}
}
else
{//otherwise apply running status
eventList.Add(ReadVoiceMessage(input, delta, (byte)prevStatus, (byte)status));
noteOnCount = TrackVoiceStats(eventList[eventList.Count - 1], instList, drumList, channelList, noteOnCount);
}
}
}
if (input.Position != endPosition)
{
throw new Exception("The track length was invalid for the current MTrk chunk.");
}
if (channelList.IndexOf(MidiHelper.DrumChannel) != -1)
{
if (drumList.IndexOf(0) == -1)
{
drumList.Add(0);
}
}
else
{
if (instList.IndexOf(0) == -1)
{
instList.Add(0);
}
}
var track = new MidiTrack(instList.ToArray(),
drumList.ToArray(),
channelList.ToArray(),
eventList.ToArray());
track.NoteOnCount = noteOnCount;
track.EndTime = totalTime;
return(track);
}
private MidiTrack ReadTrack(IReadable input)
{
var instList = new FastList<Byte>();
var drumList = new FastList<Byte>();
var channelList = new FastList<Byte>();
var eventList = new FastList<MidiEvent>();
var noteOnCount = 0;
var totalTime = 0;
while (input.Read8BitChars(4) != "MTrk")
{
var length = input.ReadInt32BE();
while (length > 0)
{
length--;
input.ReadByte();
}
}
var endPosition = input.ReadInt32BE() + input.Position;
var prevStatus = 0;
while (input.Position < endPosition)
{
var delta = ReadVariableLength(input);
totalTime += delta;
var status = input.ReadByte();
if (status >= 0x80 && status <= 0xEF)
{//voice message
prevStatus = status;
eventList.Add(ReadVoiceMessage(input, delta, (byte)status, (byte)input.ReadByte()));
noteOnCount = TrackVoiceStats(eventList[eventList.Count - 1], instList, drumList, channelList, noteOnCount);
}
else if (status >= 0xF0 && status <= 0xF7)
{//system common message
prevStatus = 0;
eventList.Add(ReadSystemCommonMessage(input, delta, (byte)status));
}
else if (status >= 0xF8 && status <= 0xFF)
{//realtime message
eventList.Add(ReadRealTimeMessage(input, delta, (byte)status));
}
else
{//data bytes
if (prevStatus == 0)
{//if no running status continue to next status byte
while ((status & 0x80) != 0x80)
{
status = input.ReadByte();
}
if (status >= 0x80 && status <= 0xEF)
{//voice message
prevStatus = status;
eventList.Add(ReadVoiceMessage(input, delta, (byte)status, (byte)input.ReadByte()));
noteOnCount = TrackVoiceStats(eventList[eventList.Count - 1], instList, drumList, channelList, noteOnCount);
}
else if (status >= 0xF0 && status <= 0xF7)
{//system common message
eventList.Add(ReadSystemCommonMessage(input, delta, (byte)status));
}
else if (status >= 0xF8 && status <= 0xFF)
{//realtime message
eventList.Add(ReadRealTimeMessage(input, delta, (byte)status));
}
}
else
{//otherwise apply running status
eventList.Add(ReadVoiceMessage(input, delta, (byte)prevStatus, (byte)status));
noteOnCount = TrackVoiceStats(eventList[eventList.Count - 1], instList, drumList, channelList, noteOnCount);
}
}
}
if (input.Position != endPosition)
throw new Exception("The track length was invalid for the current MTrk chunk.");
if (channelList.IndexOf(MidiHelper.DrumChannel) != -1)
{
if (drumList.IndexOf(0) == -1)
drumList.Add(0);
}
else
{
if (instList.IndexOf(0) == -1)
instList.Add(0);
}
var track = new MidiTrack(instList.ToArray(),
drumList.ToArray(),
channelList.ToArray(),
eventList.ToArray());
track.NoteOnCount = noteOnCount;
track.EndTime = totalTime;
return track;
}
private void ReadHeader(IReadable input)
{
if (input.ReadInt32BE() != 6)
throw new Exception("Midi header is invalid.");
TrackFormat = (MidiTrackFormat)input.ReadInt16BE();
Tracks = new MidiTrack[input.ReadInt16BE()];
var div = input.ReadInt16BE();
Division = div & 0x7FFF;
TimingStandard = ((div & 0x8000) > 0) ? MidiTimeFormat.FramesPerSecond : MidiTimeFormat.TicksPerBeat;
}
