public static Mid Create(Stream stream)
{
EndianReader reader = new EndianReader(stream, Endianness.BigEndian);
if (reader.ReadUInt32() != 0x4D546864)
{
return(null);
}
if (reader.ReadUInt32() != 6)
{
return(null);
}
Mid mid = new Mid();
mid.Type = (MidiType)reader.ReadUInt16();
ushort tracks = reader.ReadUInt16();
ushort division = reader.ReadUInt16();
if ((division & 0x8000) == 0)
{
mid.Division = new TicksPerBeatDivision((ushort)(division & 0x7FFF));
}
else
{
mid.Division = new FramesPerSecondDivision()
{
FramesPerSecond = (byte)((division & 0x7F00) >> 8),
TicksPerFrame = (byte)(division & 0x00FF)
}
};
for (int i = 0; i < tracks; i++)
{
Track track = new Track();
if (reader.ReadUInt32() != 0x4D54726B)
{
return(null);
}
uint size = reader.ReadUInt32();
uint pos = (uint)stream.Position;
byte oldb = 0;
while (stream.Position - pos < size)
{
uint delta = (uint)Mid.ReadVariable(stream);
byte b = reader.ReadByte();
if (b == 0xFF) // Meta Event
{
MetaEvent e = new MetaEvent();
e.DeltaTime = delta;
e.Type = reader.ReadByte();
uint length = (uint)Mid.ReadVariable(stream);
e.Data = reader.ReadBytes((int)length);
track.Events.Add(e);
//if (e.Type == 0x2F) // End Track meta event
//break;
}
else if (b == 0xF0)
{
throw new NotImplementedException();
}
else if (b == 0xF7)
{
throw new NotImplementedException();
}
else // Channel Event
{
ChannelEvent e = new ChannelEvent();
e.DeltaTime = delta;
if ((b & 0x80) == 0)
{
e.Parameter1 = b;
b = oldb;
}
else
{
oldb = b;
e.Parameter1 = (byte)reader.ReadByte();
}
e.Type = (byte)(b >> 4);
e.Channel = (byte)(b & 0x0F);
if (e.Type != 0xC && e.Type != 0xD)
{
e.Parameter2 = (byte)reader.ReadByte();
}
track.Events.Add(e);
}
}
mid.Tracks.Add(track);
}
return(mid);
}