MidiTest.cs

using UnityEngine;
using System.IO;
using Sanford.Multimedia.Midi;

public class MidiTest : MonoBehaviour
{
    [System.Serializable]
    public class MidiData
    {
        // All the note data
    }

    public MidiData midiData;

    public void LoadMidiData(string filePath)
    {
        FileStream midiStream = new FileStream(filePath, FileMode.Open, FileAccess.Read);
        midiData = LoadMidiData(midiStream);
    }

    public static MidiData LoadMidiData(Stream midiStream)
    {
        return ReadMidiFile(midiStream);
    }

    static MidiData ReadMidiFile(Stream midiStream)
    {
        MidiData midiData = new MidiData();
        Sequence midiSequence = new Sequence(midiStream);
        float length = midiSequence.GetLength() / midiSequence.Division;

        foreach (Track midiTrack in midiSequence)
            ReadMidiTrack(midiData, midiTrack, midiSequence.Division);

        return midiData;
    }

    static void ReadMidiTrack(MidiData midiData, Track midiTrack, int sequencerDivision)
    {
        for (int i = 0; i < midiTrack.Count; ++i)
        {
            MidiEvent midiEvent = midiTrack.GetMidiEvent(i);
            if (midiEvent.MidiMessage.GetBytes().Length < 3)
                continue;

            byte midiType = (byte)(midiEvent.MidiMessage.GetBytes()[0] & 0xFF);
            byte note = (byte)(midiEvent.MidiMessage.GetBytes()[1] & 0xFF);
            byte velocity = (byte)(midiEvent.MidiMessage.GetBytes()[2] & 0xFF);
            float time = midiEvent.AbsoluteTicks / (float)sequencerDivision;

            if (midiType == (byte)ChannelCommand.NoteOff || (midiType == (byte)ChannelCommand.NoteOn) && velocity == 0)
            {
                // Note Off
            }
            else if (midiType == (byte)ChannelCommand.NoteOn)
            {
                // Note On
            }
        }
    }
}