public static byte[] CreateTone(MusicNote note, TimeSpan duration, PCMModifiers mods)
{
mods.Init();
using (MemoryStream stream = new MemoryStream()) {
BinaryWriter writer = new BinaryWriter(stream);
WriteNote(writer,
new MidiNote()
{
Note = note,
Duration = duration,
}, mods);
return(stream.ToArray());
}
}
public static byte[] ConvertMidi(Sequence sequence, PCMModifiers mods)
{
mods.Init();
var notes = GetNotes(sequence);
int length = (int)Math.Round(notes.LastOrDefault().End.TotalSeconds *mods.SampleRate);
byte[] data = new byte[length];
using (MemoryStream stream = new MemoryStream(data)) {
BinaryWriter writer = new BinaryWriter(stream);
foreach (MidiNote note in notes)
{
WriteNote(writer, note, mods);
}
return(stream.ToArray());
}
}
private static void WriteNote(BinaryWriter writer, MidiNote note, PCMModifiers mods)
{
// Square wave
MusicNote musicNote = note.Note;
musicNote.Octave += mods.OctaveOffset;
musicNote.Octave = Math.Max(mods.MaxOctave, musicNote.Octave);
int max = (int)Math.Round(sbyte.MaxValue * note.Note.Volume * mods.Volume);
int min = (int)Math.Round(sbyte.MinValue * note.Note.Volume * mods.Volume);
int range = max - min;
//int halfRange = range / 2;
float freq = note.Note.Frequency;
float period = mods.SampleRate / freq;
int start = (int)Math.Round(note.Start.TotalSeconds * mods.SampleRate);
int length = (int)Math.Round(note.Duration.TotalSeconds * mods.SampleRate);
writer.BaseStream.Position = start;
bool up = true;
int inc = (int)Math.Round(period / 2);
int next = inc;
for (int i = 0; i < length; i++)
{
int sample;
float dif = next - i;
if (dif <= 0)
{
up = !up;
next += inc;
//dif++;
dif++;
}
if (dif >= 1)
{
if (up)
{
sample = max;
}
else
{
sample = min;
}
}
else
{
if (up != (dif >= 0.5f))
{
sample = max;
}
else
{
sample = min;
}
/*if (up)
* sample = (int) (max - range * dif);
* else
* sample = (int) (min + range * dif);*/
}
writer.Write(unchecked ((byte)(sample & 0xFF)));
}
}
public static byte[] ConvertMidi(string file, PCMModifiers mods)
{
Sequence sequence = new Sequence(file);
return(ConvertMidi(sequence, mods));
}
