void OpenStream()
{
if (IsStreamActive)
{
throw new InvalidOp("Stream alreadly opened");
}
try
{
_stream = SoundIO.InStream.Create(_device);
if (_stream.IsInvalid)
{
throw new InvalidOp("Stream allocation error");
}
if (_device.Layouts.Length == 0)
{
throw new InvalidOp("No channel layout");
}
// Calculate the best latency.
// TODO: Should we use the target frame rate instead of 1/60?
var bestLatency = Math.Max(1.0 / 60, _device.SoftwareLatencyMin);
// Stream properties
_stream.Format = SoundIO.Format.Float32LE;
_stream.Layout = _device.Layouts[0];
_stream.SoftwareLatency = bestLatency;
_stream.ReadCallback = _readCallback;
_stream.OverflowCallback = _overflowCallback;
_stream.ErrorCallback = _errorCallback;
_stream.UserData = GCHandle.ToIntPtr(_self);
var err = _stream.Open();
if (err != SoundIO.Error.None)
{
throw new InvalidOp($"Stream initialization error ({err})");
}
// We want the buffers to meet the following requirements:
// - Doesn't overflow if the main thread pauses for 4 frames.
// - Doesn't overflow if the callback is invoked 4 times a frame.
var latency = Math.Max(_stream.SoftwareLatency, bestLatency);
var bufferSize = CalculateBufferSize((float)(latency * 4));
// Ring/window buffer allocation
_ring = new RingBuffer(bufferSize);
_window = new byte[bufferSize];
// Start streaming.
_stream.Start();
}
catch
{
// Dispose the stream on an exception.
_stream?.Dispose();
_stream = null;
throw;
}
_audioLevels = new LevelMeter(_stream.Layout.ChannelCount)
{
SampleRate = _stream.SampleRate
};
}
readonly float _bufferingTimeSec = 0.5f; // 0.5[sec]
#endregion
#region Stream initialization
void OpenStream()
{
if (_device is null)
{
throw new InvalidOp("Invalid device");
}
try
{
_stream = SoundIO.InStream.Create(_device);
if (_stream.IsInvalid)
{
throw new InvalidOp("Stream allocation error");
}
if (_device.Layouts.Length == 0)
{
throw new InvalidOp("No channel layout");
}
// Calculate the best latency.
// TODO: Should we use the target frame rate instead of 1/60?
var bestLatency = Math.Max(1.0 / 60, _device.SoftwareLatencyMin);
// Stream properties
_stream.Format = SoundIO.Format.Float32LE;
_stream.Layout = _device.Layouts[0];
_stream.SoftwareLatency = bestLatency;
_stream.ReadCallback = _readCallback;
_stream.OverflowCallback = _overflowCallback;
_stream.ErrorCallback = _errorCallback;
_stream.UserData = GCHandle.ToIntPtr(_self);
var err = _stream.Open();
if (err != SoundIO.Error.None)
{
throw new InvalidOp($"Stream initialization error ({err})");
}
// Calculate buffer size
var ringBufferSize = (int)(_stream.Layout.ChannelCount * _stream.SampleRate * _bufferingTimeSec);
var frameBufferSize = (int)(_frameDurationMs / 1000.0f * _stream.Layout.ChannelCount * _stream.SampleRate);
// Ring/frame buffer allocation
_ring = new RingBuffer <float>(ringBufferSize);
_frameBuffer = new float[frameBufferSize];
// Start streaming.
_stream.Start();
}
catch
{
// Dispose the stream on an exception.
_stream?.Dispose();
_stream = null;
_device?.Dispose();
_device = null;
throw;
}
}