/// <summary>
/// Process a message, adjusting the MIDI context
/// </summary>
/// <param name="message">The message to process</param>
public void ProcessMessage(MidiMessage message)
{
var hasStatus = true;
if (0 != message.Status)
{
RunningStatus = message.Status;
}
else
{
hasStatus = false;
}
int cn = (hasStatus ? message.Status & 0xF : (0XFF != ChannelPrefix ? ChannelPrefix : (RunningStatus & 0xF)));
switch (RunningStatus & 0xF0)
{
case 0xC0:
var mb = message as MidiMessageByte;
Channels[cn].Patch = mb.Data1;
break;
case 0xD0:
mb = message as MidiMessageByte;
Channels[cn].ChannelPressure = mb.Data1;
break;
case 0x80:
var mw = message as MidiMessageWord;
Channels[cn].Notes[mw.Data1] = 0;
break;
case 0x90:
mw = message as MidiMessageWord;
Channels[cn].Notes[mw.Data1] = mw.Data2;
break;
case 0xA0:
mw = message as MidiMessageWord;
Channels[cn].KeyPressure[mw.Data1] = mw.Data2;
break;
case 0xB0:
mw = message as MidiMessageWord;
// respect send all notes off as necessary
if (mw.Data1 >= 123 && mw.Data2 >= 127)
{
for (int i = 0; i < 128; ++i)
{
var b = Channels[cn].Notes[i];
if (0xFF != b)
{
Channels[cn].Notes[i] = 0;
}
}
}
Channels[cn].Controls[mw.Data1] = mw.Data2;
break;
case 0xE0:
mw = message as MidiMessageWord;
Channels[cn].PitchWheel = mw.Data;
break;
case 0xF0:
switch (RunningStatus & 0xF)
{
case 0xF:
var mbs = message as MidiMessageMeta;
switch (mbs.Data1)
{
case 0x20:
ChannelPrefix = mbs.Data[0];
break;
case 0x51:
if (BitConverter.IsLittleEndian)
{
MicroTempo = (mbs.Data[0] << 16) | (mbs.Data[1] << 8) | mbs.Data[2];
}
else
{
MicroTempo = (mbs.Data[2] << 16) | (mbs.Data[1] << 8) | mbs.Data[0];
}
break;
case 0x58:
TimeSignature = new MidiTimeSignature(mbs.Data[0], (byte)Math.Pow(mbs.Data[1], 2), mbs.Data[2], mbs.Data[3]);
break;
}
break;
}
break;
}
}
/// <summary>
/// Creates an event at the specified position with the specified MIDI message
/// </summary>
/// <param name="position">The position in MIDI ticks</param>
/// <param name="message">The MIDI message for this event</param>
public MidiEvent(int position, MidiMessage message)
{
Position = position;
Message = message;
}
internal static MidiSequence ReadFrom(Stream stream)
{
MidiSequence result = new MidiSequence();
var rs = (byte)0;
var delta = _ReadVarlen(stream);
if (BitConverter.IsLittleEndian)
{
delta = _Swap(delta);
}
var i = stream.ReadByte();
while (-1 != i)
{
var hasStatus = false;
var b = (byte)i;
if (0x7F < b)
{
hasStatus = true;
rs = b;
i = stream.ReadByte();
if (-1 != i)
{
b = (byte)i;
}
else
{
b = 0;
}
}
var st = hasStatus ? rs : (byte)0;
var m = (MidiMessage)null;
switch (rs & 0xF0)
{
case 0x80:
if (i == -1)
{
throw new EndOfStreamException();
}
m = new MidiMessageNoteOff(b, (byte)stream.ReadByte(), unchecked ((byte)(st & 0x0F)));
break;
case 0x90:
if (i == -1)
{
throw new EndOfStreamException();
}
m = new MidiMessageNoteOn(b, (byte)stream.ReadByte(), unchecked ((byte)(st & 0x0F)));
break;
case 0xA0:
if (i == -1)
{
throw new EndOfStreamException();
}
m = new MidiMessageKeyPressure(b, (byte)stream.ReadByte(), unchecked ((byte)(st & 0x0F)));
break;
case 0xB0:
if (i == -1)
{
throw new EndOfStreamException();
}
m = new MidiMessageCC(b, (byte)stream.ReadByte(), unchecked ((byte)(st & 0x0F)));
break;
case 0xC0:
if (i == -1)
{
throw new EndOfStreamException();
}
m = new MidiMessagePatchChange(b, unchecked ((byte)(st & 0x0F)));
break;
case 0xD0:
if (i == -1)
{
throw new EndOfStreamException();
}
m = new MidiMessageChannelPressure(b, unchecked ((byte)(st & 0x0F)));
break;
case 0xE0:
if (i == -1)
{
throw new EndOfStreamException();
}
m = new MidiMessageChannelPitch(b, (byte)stream.ReadByte(), unchecked ((byte)(st & 0x0F)));
break;
case 0xF0:
switch (rs & 0xF)
{
case 0xF:
if (i == -1)
{
throw new EndOfStreamException();
}
var l = _ReadVarlen(stream);
//if (BitConverter.IsLittleEndian)
// l = _Swap(l);
var ba = new byte[l];
if (l != stream.Read(ba, 0, ba.Length))
{
throw new EndOfStreamException();
}
m = new MidiMessageMeta(st, b, ba);
break;
case 0x0:
case 0x7:
if (i == -1)
{
throw new EndOfStreamException();
}
l = _ReadVarlen(b, stream);
//if (BitConverter.IsLittleEndian)
// l = _Swap(l);
ba = new byte[l];
if (l != stream.Read(ba, 0, ba.Length))
{
throw new EndOfStreamException();
}
m = new MidiMessageSysex(st, ba);
break;
case 0x2:
if (i == -1)
{
throw new EndOfStreamException();
}
m = new MidiMessageWord(st, b, (byte)stream.ReadByte());
break;
case 0x3:
if (i == -1)
{
throw new EndOfStreamException();
}
m = new MidiMessageByte(st, b);
break;
case 0x6:
case 0x8:
case 0xA:
case 0xB:
case 0xC:
// status *was* specified if we got here
m = new MidiMessage(st);
break;
default:
throw new NotSupportedException("The MIDI message is not recognized.");
}
break;
}
result.Events.Add(new MidiEvent(delta, m));
i = _ReadVarlen(stream);
if (-1 == i)
{
break;
}
delta = i;
i = stream.ReadByte();
}
return(result);
}
