/// <summary>
/// Reads an event from the reader's underlying stream.
/// </summary>
/// <param name="reader">Reader to read an event.</param>
/// <param name="settings">Settings according to which an event must be read.</param>
/// <param name="channelEventStatusByte">Current channel event status byte used as running status.</param>
/// <returns>Instance of the <see cref="MidiEvent"/> representing a MIDI event.</returns>
/// <exception cref="ObjectDisposedException">Method was called after the writer's underlying stream
/// was disposed.</exception>
/// <exception cref="IOException">An I/O error occurred on the writer's underlying stream.</exception>
/// <exception cref="UnexpectedRunningStatusException">Unexpected running status is encountered.</exception>
/// <exception cref="UnknownChannelEventException">Reader has encountered an unknown channel event.</exception>
/// <exception cref="NotEnoughBytesException">Not enough bytes to read an event.</exception>
/// <exception cref="InvalidChannelEventParameterValueException">Value of a channel event's parameter just
/// read is invalid.</exception>
private MidiEvent ReadEvent(MidiReader reader, ReadingSettings settings, ref byte?channelEventStatusByte)
{
var deltaTime = reader.ReadVlqLongNumber();
if (deltaTime < 0)
{
deltaTime = 0;
}
//
var statusByte = reader.ReadByte();
if (statusByte <= SevenBitNumber.MaxValue)
{
if (channelEventStatusByte == null)
{
throw new UnexpectedRunningStatusException();
}
statusByte = channelEventStatusByte.Value;
reader.Position--;
}
//
var eventReader = EventReaderFactory.GetReader(statusByte, smfOnly: true);
var midiEvent = eventReader.Read(reader, settings, statusByte);
//
if (settings.SilentNoteOnPolicy == SilentNoteOnPolicy.NoteOff)
{
var noteOnEvent = midiEvent as NoteOnEvent;
if (noteOnEvent?.Velocity == 0)
{
midiEvent = new NoteOffEvent
{
DeltaTime = noteOnEvent.DeltaTime,
Channel = noteOnEvent.Channel,
NoteNumber = noteOnEvent.NoteNumber
};
}
}
//
if (midiEvent is ChannelEvent)
{
channelEventStatusByte = statusByte;
}
//
midiEvent.DeltaTime = deltaTime;
return(midiEvent);
}
// TODO: improve performance
/// <summary>
/// Converts the specified status byte and data bytes to an instance of the <see cref="MidiEvent"/>.
/// </summary>
/// <param name="statusByte">The status byte of MIDI event.</param>
/// <param name="dataBytes">Data bytes of MIDI event (bytes except status byte). Can be null
/// if MIDI event has no data bytes.</param>
/// <returns><see cref="MidiEvent"/> read from <paramref name="statusByte"/> and <paramref name="dataBytes"/>.</returns>
public MidiEvent Convert(byte statusByte, byte[] dataBytes)
{
_dataBytesStream.Seek(0, SeekOrigin.Begin);
if (dataBytes != null)
{
_dataBytesStream.Write(dataBytes, 0, dataBytes.Length);
}
_dataBytesStream.Seek(0, SeekOrigin.Begin);
var eventReader = EventReaderFactory.GetReader(statusByte, smfOnly: false);
return(eventReader.Read(_midiReader, ReadingSettings, statusByte));
}
private MidiEvent ReadEvent(MidiReader reader, ReadingSettings settings, ref byte?channelEventStatusByte, out long deltaTime)
{
// LOGREAD: e a
// LOGREAD: dt a
deltaTime = reader.ReadVlqLongNumber();
if (deltaTime < 0)
{
deltaTime = 0;
}
// LOGREAD: dt z <{deltaTime}>
// LOGREAD: m a
var statusByte = reader.ReadByte();
if (statusByte <= SevenBitNumber.MaxValue)
{
if (channelEventStatusByte == null)
{
throw new UnexpectedRunningStatusException();
}
statusByte = channelEventStatusByte.Value;
reader.Position--;
}
//
var eventReader = EventReaderFactory.GetReader(statusByte, smfOnly: true);
var midiEvent = eventReader.Read(reader, settings, statusByte);
//
if (midiEvent is ChannelEvent)
{
channelEventStatusByte = statusByte;
}
//
if (midiEvent != null)
{
midiEvent._deltaTime = deltaTime;
}
// LOGREAD: m z
// LOGREAD: e z <{midiEvent}>
return(midiEvent);
}
