public double Update(double sample)
{
var takeAway = queue[head];
queue[head] = sample;
head++;
if (head >= sampleCount)
{
head = 0;
}
sum -= takeAway;
sum += sample;
var sampleDb = Utils.Gain2Db(sample);
var takeAwayDb = Utils.Gain2Db(takeAway);
if (sampleDb < -150)
{
sampleDb = -150;
}
if (takeAwayDb < -150)
{
takeAwayDb = -150;
}
dbDecayPerSample = (sampleDb - takeAwayDb) / sampleCount;
return(sum / sampleCount);
}
public void Run()
{
/*var pm = new PlotModel();
* var xs = Enumerable.Range(0, 1000).Select(x => x / 1000.0).Select(x => -100 + x * 100).ToArray();
* var ys1 = xs.Select(x => Compress(x, ThresholdDb, UpperSlope, 3, true)).ToArray();
* var ys2 = xs.Select(x => Compress(x, ThresholdDb + 6, LowerSlope, 3, true)).ToArray();
*
* pm.AddLine(xs, ys1);
* pm.AddLine(xs, ys2);
* pm.Show();
*/
var pm = new PlotModel();
pm.Axes.Add(new LinearAxis {
Position = AxisPosition.Left, Key = "L"
});
pm.Axes.Add(new LinearAxis {
Position = AxisPosition.Right, Key = "R"
});
var follower = new EnvelopeFollower(48000, 20);
var expander = new Expander();
var slewLimiter = new SlewLimiter(48000);
follower.SetRelease(ReleaseMs);
slewLimiter.UpdateDb60(2.0, ReleaseMs);
expander.Update(ThresholdDb, ReductionDb, UpperSlope);
var signalValues = new List <double>();
var followerValues = new List <double>();
var gainValues = new List <double>();
var rand = new Random();
Func <double> random = () => 2 * rand.NextDouble() - 1;
double decay = 1.0;
for (int i = 0; i < 20000; i++)
{
var x = (Math.Sin(i / fs * 2 * Math.PI * 300) + random() * 0.4) * decay;
decay *= 0.9998;
if (i < 1000)
{
x = random() * 0.001;
}
else if (i > 12000)
{
x = random() * 0.001;
}
signalValues.Add(x);
follower.ProcessEnvelope(x);
var env = follower.GetOutput();
followerValues.Add(env);
expander.Expand(Utils.Gain2Db(env));
var gainDb = expander.GetOutput();
gainDb = slewLimiter.Process(gainDb);
var gain = Utils.Db2Gain(gainDb);
gainValues.Add(gain);
}
var signalLine = pm.AddLine(signalValues);
signalLine.Title = "Signal";
signalLine.YAxisKey = "R";
//pm.AddLine(followerValues.Select(Utils.Gain2Db)).Title = "followerValues";
pm.AddLine(gainValues.Select(Utils.Gain2Db)).Title = "gainValues";
pm.Show();
}
