/// <summary>
/// Method implements simple phaser effect
/// </summary>
/// <param name="signal"></param>
/// <param name="filteringOptions"></param>
/// <returns></returns>
public DiscreteSignal ApplyTo(DiscreteSignal signal,
FilteringOptions filteringOptions = FilteringOptions.Auto)
{
var x = signal.Samples;
var samplingRateInverted = 1.0 / signal.SamplingRate;
var lfo = new TriangleWaveBuilder()
.SetParameter("lo", MinFrequency)
.SetParameter("hi", MaxFrequency)
.SetParameter("freq", LfoFrequency)
.OfLength(signal.Length)
.SampledAt(signal.SamplingRate)
.Build();
var y = new float[x.Length];
for (var i = 2; i < signal.Length; i++)
{
var filter = new NotchFilter((float)(lfo[i] * samplingRateInverted), Q);
var b = filter.Tf.Numerator;
var a = filter.Tf.Denominator;
y[i] = (float)(b[0] * x[i] + b[1] * x[i - 1] + b[2] * x[i - 2] - (a[1] * y[i - 1] + a[2] * y[i - 2]));
}
return(new DiscreteSignal(signal.SamplingRate, y));
}
private void btnAddFilter_Click(object sender, RoutedEventArgs e)
{
Filter filter = null;
switch ((sender as FrameworkElement).Name)
{
case "btnAddLPF": filter = new LowPassFilter(Filter.DefaultN, (double)globalSampleRate / 4); break;
case "btnAddHPF": filter = new HighPassFilter(Filter.DefaultN, (double)globalSampleRate / 4); break;
case "btnAddBPF": filter = new BandPassFilter(Filter.DefaultN, (double)globalSampleRate / 8, (double)globalSampleRate * 3 / 8); break;
case "btnAddBSF": filter = new BandStopFilter(Filter.DefaultN, (double)globalSampleRate / 8, (double)globalSampleRate * 3 / 8); break;
case "btnAddMF": filter = new AverageFilter(Filter.DefaultN); break;
case "btnAddZPass": filter = new ZFilterPass(ZFilterPass.DefaultR, (double)globalSampleRate / 4); break;
case "btnAddZPass1": filter = new ZFilterPass1(ZFilterPass1.DefaultR, (double)globalSampleRate / 4); break;
case "btnAddNotch": filter = new NotchFilter(NotchFilter.DefaultR1, NotchFilter.DefaultR2, (double)globalSampleRate / 4); break;
default: return;
}
filter.PropertyChanged += new PropertyChangedEventHandler(Filter_PropertyChanged);
filters.Add(filter);
filtersList.SelectedIndex = filters.IndexOf(filter);
updateResult();
}
public Demodulator NotchFilter(NotchFilter filter)
{
_radio.Check(_api.SetNotchFilter(_radio.GetHandle(), _ddc2.Channel(), filter.Active));
_radio.Check(_api.SetNotchFilterBandwidth(_radio.GetHandle(), _ddc2.Channel(), filter.Bandwidth));
_radio.Check(_api.SetNotchFilterFrequency(_radio.GetHandle(), _ddc2.Channel(), filter.Frequency));
return(this);
}
/// <summary>
/// Constructor
/// </summary>
/// <param name="samplingRate"></param>
/// <param name="lfo"></param>
/// <param name="q"></param>
public PhaserEffect(int samplingRate, SignalBuilder lfo, float q = 0.5f)
{
_fs = samplingRate;
Q = q;
Lfo = lfo;
_filter = new NotchFilter(Lfo.NextSample() / _fs, Q);
}
public bool TryNotchFilter(NotchFilter filter)
{
var res = _api.SetNotchFilter(_radio.GetHandle(), _ddc2.Channel(), filter.Active);
res &= _api.SetNotchFilterBandwidth(_radio.GetHandle(), _ddc2.Channel(), filter.Bandwidth);
res &= _api.SetNotchFilterFrequency(_radio.GetHandle(), _ddc2.Channel(), filter.Frequency);
return(res);
}
/// <summary>
/// Constructor
/// </summary>
/// <param name="samplingRate"></param>
/// <param name="q"></param>
/// <param name="lfoFrequency"></param>
/// <param name="minFrequency"></param>
/// <param name="maxFrequency"></param>
public PhaserEffect(int samplingRate,
float lfoFrequency = 1.0f,
float minFrequency = 300,
float maxFrequency = 3000,
float q = 0.5f)
{
_fs = samplingRate;
Lfo = new TriangleWaveBuilder().SampledAt(samplingRate);
LfoFrequency = lfoFrequency;
MinFrequency = minFrequency;
MaxFrequency = maxFrequency;
Q = q;
_filter = new NotchFilter(Lfo.NextSample() / _fs, Q);
}
/// <summary>
/// Function for configuring the IF notch filter.
/// </summary>
/// <param name="notchFilter"><see cref="Devices.NotchFilter"/> Notch parameters</param>
/// <returns>Returns <see cref="G313Demodulator"/></returns>
public G313Demodulator NotchFilter(NotchFilter notchFilter)
{
var result = TryNotchFilter(notchFilter);
return(CheckFluent(result, "failed to set notch filter"));
}
/// <summary>
/// Function for configuring the IF notch filter.
/// </summary>
/// <param name="notchFilter"><see cref="Devices.NotchFilter"/> filter parameters</param>
/// <returns>Returns true if Notch filter parameters are set.</returns>
public bool TryNotchFilter(NotchFilter notchFilter)
{
return(G313DemodulatorApi.SetNotchFilter(GetHandle(), notchFilter.Active, notchFilter.Frequency, notchFilter.Bandwidth));
}
