2012/07/05(木)C#でMidiファイルを読む
2012/07/05 21:49 C#でMidiファイルを読む。
とりあえず、読めればいいや版。
/* MidiFile.cs */
using System;
using System.Collections.Generic;
using System.Text;
using System.IO;
namespace Tsukikage.WinMM.MidiIO
{
public enum EventType
{
NoteOff = 0x80,
NoteOn = 0x90,
PolyKeyPress = 0xA0,
ControlChange = 0xB0,
ProgramChange = 0xC0,
ChannelPress = 0xD0,
PichBend = 0xE0,
SystemExclusive = 0xF0,
SequenceNumber = 0xFF00,
TextEvent = 0xFF01,
CopyrightNotice = 0xFF02,
TrackName = 0xFF03,
InstrumentName = 0xFF04,
LyricText = 0xFF05,
MarkerText = 0xFF06,
CuePoint = 0xFF07,
MidiChannelPrefix = 0xFF20,
EndOfTrack = 0xFF2F,
TempoSetting = 0xFF51,
SMTPEOffset = 0xFF54,
TimeSigunature = 0xFF58,
KeySigunature = 0xFF59,
SequencerSpecificEvent = 0xFF7F,
}
public class MidiSequence
{
#region StreamReader
static int ReadInt2(Stream s)
{
int a = 0;
a = a << 8 | s.ReadByte();
a = a << 8 | s.ReadByte();
return a;
}
static int ReadInt3(Stream s)
{
int a = 0;
a = a << 8 | s.ReadByte();
a = a << 8 | s.ReadByte();
a = a << 8 | s.ReadByte();
return a;
}
static int ReadInt4(Stream s)
{
int a = 0;
a = a << 8 | s.ReadByte();
a = a << 8 | s.ReadByte();
a = a << 8 | s.ReadByte();
a = a << 8 | s.ReadByte();
return a;
}
static int ReadIntX(Stream s)
{
int a = 0;
while (true)
{
int c = s.ReadByte();
a = a << 7 | (c & 0x7F);
if ((c & 0x80) == 0)
break;
}
return a;
}
static string ReadText(Stream s)
{
int length = ReadIntX(s);
byte[] buf = new byte[length];
s.Read(buf, 0, length);
return Encoding.GetEncoding(932).GetString(buf, 0, length);
}
static byte[] ReadSysEx(Stream s)
{
int length = ReadIntX(s);
byte[] buf = new byte[length+1];
buf[0] = 0xF0; s.Read(buf, 1, length);
return buf;
}
static void ReadUnknownMeta(Stream s)
{
int length = ReadIntX(s);
byte[] buf = new byte[length];
s.Read(buf, 0, length);
}
#endregion
public string Title = null, Copyright = null;
public int Tracks;
public int TimeBase;
public MidiSequence(Stream source)
{
Load(source);
}
public MidiSequence(string path)
{
using (FileStream fs = File.OpenRead(path))
{
Load(fs);
}
}
void Load(Stream fs)
{
List<string> stringTable = new List<string>(256);
List<byte[]> sysexTable = new List<byte[]>(256);
List<MidiEvent> eventList = new List<MidiEvent>(65536);
{ // Read HEADER
if (ReadInt4(fs) != 0x4D546864) /* MThd */
{
byte[] aaa = new byte[256];
fs.Read(aaa, 0, 16); /* RIFF MIDI */
if (ReadInt4(fs) != 0x4D546864) /* MThd */
{
fs.Read(aaa, 0, 108); /* MAC BINARY */
if (ReadInt4(fs) != 0x4D546864) /* MThd */
throw new ArgumentException("SMF/RMIじゃないっぽい", "path");
}
}
int len = ReadInt4(fs);
int fmt = ReadInt2(fs);
Tracks = ReadInt2(fs);
TimeBase = ReadInt2(fs);
}
for (int track = 0; track < Tracks; track++)
{
if (ReadInt4(fs) != 0x4D54726B) /* MTrk */
throw new ArgumentException("SMFが壊れてるか対応してないっぽです。", "path");
int end = ReadInt4(fs) + (int)fs.Position;
int currentPos = 0;
int lastStatus = 0;
while (fs.Position < end)
{
currentPos += ReadIntX(fs); // deltaTime
int first = -1, second = -1, third = -1;
first = fs.ReadByte();
if ((first & 0xF0) == 0)
{
// running status
second = first;
first = lastStatus;
}
lastStatus = first;
int eventType = first & 0xF0;
if (eventType != 0xF0)
{
// short message
second = second != -1 ? second : fs.ReadByte();
if (eventType != 0xC0) third = fs.ReadByte();
else third = 0;
eventList.Add(new MidiEvent(currentPos, (EventType)eventType, first, second, third));
}
else if (first == 0xF0 || first == 0xF7)
{
// long message
byte[] ex = ReadSysEx(fs);
eventList.Add(new MidiEvent(currentPos, EventType.SystemExclusive, sysexTable.Count));
sysexTable.Add(ex);
}
else if (first == 0xFF)
{
// meta event
EventType metatype = (EventType)(0xFF00 | fs.ReadByte());
switch (metatype)
{
case EventType.TextEvent:
case EventType.CopyrightNotice:
case EventType.TrackName:
case EventType.LyricText:
case EventType.MarkerText:
case EventType.CuePoint:
string text = ReadText(fs);
eventList.Add(new MidiEvent(currentPos, metatype, stringTable.Count));
if ((EventType)metatype == EventType.CopyrightNotice) Copyright = text;
if ((EventType)metatype == EventType.TrackName && Title == null) Title = text;
stringTable.Add(text);
break;
case EventType.TempoSetting:
ReadIntX(fs);
eventList.Add(new MidiEvent(currentPos, metatype, ReadInt3(fs)));
break;
case EventType.TimeSigunature:
ReadIntX(fs);
eventList.Add(new MidiEvent(currentPos, metatype, ReadInt4(fs)));
break;
case EventType.KeySigunature:
ReadIntX(fs);
eventList.Add(new MidiEvent(currentPos, metatype, ReadInt2(fs)));
break;
default:
ReadUnknownMeta(fs);
break;
}
}
}
}
// All Tracks was readed.
Events = eventList.ToArray();
MargeSort(Events, delegate(MidiEvent x, MidiEvent y) { return x.Position - y.Position; });
StringTable = stringTable.ToArray();
SysExTable = sysexTable.ToArray();
}
/// <summary>
/// 入力されたノートオンイベントに対するノートオフの位置を検索する。
/// </summary>
/// <param name="noteOnEvent">noteOnEvent</param>
/// <returns>位置</returns>
public int GetNoteOffEventIndex(int noteOnEvent)
{
int i = noteOnEvent + 1;
if (Events[noteOnEvent].EventType != EventType.NoteOn)
new ArgumentException("NoteOnイベントのインデックスではないようです。", "noteOnEvent");
int noteCh = Events[noteOnEvent].Channel;
int noteNum = Events[noteOnEvent].NoteNumber;
int noteVel = Events[noteOnEvent].NoteVelocity;
for (; i < Events.Length; i++)
{
MidiEvent e = Events[i];
if (e.EventType == EventType.NoteOff && e.Channel == noteCh && e.NoteNumber == noteNum)
return i;
if (e.EventType == EventType.NoteOn && e.Channel == noteCh && e.NoteNumber == noteNum && e.NoteVelocity == 0)
return i;
}
return -1;
}
public MidiEvent[] Events;
public String[] StringTable;
public byte[][] SysExTable;
static void MargeSort<T>(T[] target, Comparison<T> comparer)
{
T[] work = new T[target.Length];
for (int i = 0; ; i++)
{
int n = 1 << i;
int m = n * 2;
for (int j = 0; ; j++)
{
int p = m * j;
int p1 = p, e1 = p1 + n;
int p2 = e1, e2 = Math.Min(p2 + n, target.Length);
int seg = e2 - p1;
if (seg <= n) break;
for (int k = 0; k < seg; k++)
{
if (p2 >= e2) work[k] = target[p1++];
else if (p1 >= e1) work[k] = target[p2++];
else if (comparer(target[p1], target[p2]) <= 0) work[k] = target[p1++];
else work[k] = target[p2++];
}
Array.Copy(work, 0, target, p, seg);
}
if (n >= target.Length) break;
}
}
}
public struct MidiEvent
{
public MidiEvent(int position, EventType type, int data)
{
this.position = position;
this.type = type;
this.data = data;
this.UserData = 0;
if (this.type == EventType.NoteOn && NoteVelocity == 0)
{
this.data ^= 0x10;
this.type = EventType.NoteOff;
}
}
public MidiEvent(int position, EventType type, int first, int second, int third)
{
this.position = position;
this.type = type;
this.data = first | second << 8 | third << 16;
this.UserData = 0;
if (this.type == EventType.NoteOn && NoteVelocity == 0)
{
this.data ^= 0x10;
this.type = EventType.NoteOff;
}
}
int position;
EventType type;
int data;
public int UserData;
public int Position { get { return position; } }
public EventType EventType { get { return type; } }
public int Channel { get { return data & 0x0F; } }
public int NoteNumber { get { return data >> 8 & 0xFF; } }
public int NoteVelocity { get { return data >> 16 & 0xFF; } }
public int ControlNumber { get { return data >> 8 & 0xFF; } }
public int ControlValue { get { return data >> 16 & 0xFF; } }
public int ProgramNumber { get { return data >> 8 & 0xFF; } }
public int PichBend { get { return (data >> 1 & 0x3F80) | (data >> 16 & 0x7F); } }
public int Tempo { get { return data; } }
public double BPM { get { return 60000000.0 / data; } }
public int TimeNum { get { return data >> 24 & 0xFF; } }
public int TimeDenom { get { return data >> 16 & 0xFF; } }
public int TimeBeat { get { return data >> 8 & 0xFF; } }
public int ScaleSharps { get { return data >> 8 & 0xFF; } }
public int ScaleMajor { get { return data & 0xFF; } }
public int SysExIndex { get { return data; } }
public int TextIndex { get { return data; } }
public uint RawData { get { return (uint)data; } }
public override string ToString()
{
string pos = "" + (position / 1920 + 1).ToString("D4") + "." + (position % 1920 / 480 + 1) + "." + (position % 480).ToString("D3") + " > ";
switch (EventType)
{
case EventType.NoteOn: return pos + "NoteOn : Ch." + Channel + " N" + NoteNumber + " V" + NoteVelocity;
case EventType.NoteOff: return pos + "NoteOff : Ch." + Channel + " N" + NoteNumber;
case EventType.ProgramChange: return pos + "ProgChg : Ch." + Channel + " Prog." + ProgramNumber;
case EventType.ControlChange: return pos + "CtrlChg : Ch." + Channel + " CC" + ControlNumber + ">" + ControlValue;
case EventType.PichBend: return pos + "PichBend : Ch." + Channel + " PB." + PichBend;
case EventType.ChannelPress: return pos + "ChannelPress : Ch." + Channel;
case EventType.PolyKeyPress: return pos + "PolyKeyPress : Ch." + Channel + " N" + NoteNumber + " V" + NoteVelocity;
case EventType.SystemExclusive: return pos + "SysEx : " + data;
case EventType.TempoSetting: return pos + "Tempo : " + data + "μs/beat = BPM. " + BPM + ")";
case EventType.TimeSigunature: return pos + "TimeSign : " + TimeNum + " / " + "2^" + TimeDenom;
case EventType.KeySigunature: return pos + "KeySign : Sharps." + ScaleSharps + " " + (ScaleMajor == 1 ? "Major" : "Minor");
case EventType.TextEvent: return pos + "Text : " + data;
case EventType.TrackName: return pos + "TrackName : " + data;
case EventType.CopyrightNotice: return pos + "Copyright : " + data;
case EventType.InstrumentName: return pos + "InstName : " + data;
case EventType.LyricText: return pos + "Lyric : " + data;
case EventType.MarkerText: return pos + "Marker : " + data;
case EventType.CuePoint: return pos + "CuePoint : " + data;
default: return pos + EventType.ToString() + " : " + data;
}
}
}
}