//private static void Reader_FrameArrived(object sender, AudioBeamFrameArrivedEventArgs e) {
//}
private static void UpdateAudio()
{
audioFrameAvailable = false;
if (audioReader != null)
{
IList <AudioBeamFrame> frames = audioReader.AcquireLatestBeamFrames();
for (int i = 0; i < frames.Count; i++)
{
AudioBeamFrame frame = frames[i];
if (frame != null)
{
audioFrameAvailable = true;
IList <AudioBeamSubFrame> subframes = frame.SubFrames;
for (int j = 0; j < subframes.Count; j++)
{
AudioBeamSubFrame subframe = subframes[j];
if (subframe != null)
{
beamAngle = subframe.BeamAngle;
ProcessAudio(subframe);
subframe.Dispose();
}
}
frame.Dispose();
}
}
}
}
private static void ProcessAudio(AudioBeamSubFrame subFrame)
{
// Process audio buffer
subFrame.CopyFrameDataToArray(audioBuffer);
for (int i = 0; i < audioBuffer.Length; i += BytesPerSample)
{
// Extract the 32-bit IEEE float sample from the byte array
float audioSample = BitConverter.ToSingle(audioBuffer, i);
accumulatedSquareSum += audioSample * audioSample;
++accumulatedSampleCount;
if (accumulatedSampleCount < SamplesPerColumn)
{
continue;
}
float meanSquare = accumulatedSquareSum / SamplesPerColumn;
if (meanSquare > 1.0f)
{
// A loud audio source right next to the sensor may result in mean square values
// greater than 1.0. Cap it at 1.0f for display purposes.
meanSquare = 1.0f;
}
// Calculate energy in dB, in the range [MinEnergy, 0], where MinEnergy < 0
energyAmount = MinEnergy;
if (meanSquare > 0)
{
energyAmount = (float)(10.0 * Math.Log10(meanSquare));
}
lock (energyLock) {
// Normalize values to the range [0, 1] for display
energy[energyIndex] = (MinEnergy - energyAmount) / MinEnergy;
energyIndex = (energyIndex + 1) % energy.Length;
++newEnergyAvailable;
}
accumulatedSquareSum = 0;
accumulatedSampleCount = 0;
}
}
