static private WaveChunk MakeSquareWave(WaveAttributes waveAttributes)
{
WaveChunk wave = MakeSineWave(waveAttributes);
uint nSamples = wave.NumSamples;
for (uint i = 0; i < nSamples; i++)
{
wave[i] = Math.Sign(wave[i]);
}
return(wave);
}
static private WaveChunk MakeWhiteNoise(WaveAttributes waveAttr)
{
WaveChunk wave = new WaveChunk(waveAttr.WaveSampleRate, waveAttr.Runtime);
uint numSamples = wave.NumSamples;
Random random = new Random();
for (uint i = 0; i < numSamples; i++)
{
wave[i] = (float)(2 * random.NextDouble() - 1);
}
return(wave);
}
static private WaveChunk MakeSineWave(WaveAttributes waveAttributes)
{
WaveChunk wave = new WaveChunk(waveAttributes.WaveSampleRate, waveAttributes.Runtime);
uint numSamples = wave.NumSamples;
double t = (Math.PI * 2 * waveAttributes.TargetFrequency) / (uint)waveAttributes.WaveSampleRate;
for (uint i = 0; i < numSamples; i++)
{
wave[i] = (float)Math.Sin(t * i);
}
return(wave);
}
private static WaveChunk MakeTriangle(WaveAttributes waveAttr)
{
WaveChunk wave = new WaveChunk(waveAttr.WaveSampleRate, waveAttr.Runtime);
uint numSamples = wave.NumSamples;
float step = (float)(1 / (double)waveAttr.WaveSampleRate * 4 * waveAttr.TargetFrequency);
wave[0] = 0.0f;
for (uint i = 1; i < numSamples; i++)
{
var next = wave[i - 1] + step;
if (Math.Abs(next) > 1.0f)
{
step = -step;
}
wave[i] = wave[i - 1] + step;
}
return(wave);
}
private static WaveChunk MakeSawtooth(WaveAttributes waveAttr)
{
WaveChunk wave = new WaveChunk(waveAttr.WaveSampleRate, waveAttr.Runtime);
uint numSamples = wave.NumSamples;
var step = 1 / (double)waveAttr.WaveSampleRate * 2 * waveAttr.TargetFrequency;
wave[0] = 0.0f;
for (uint i = 1; i < numSamples; i++)
{
var next = wave[i - 1] + (float)step;
if (next > 1.0f)
{
wave[i] = -1.0f;
}
else
{
wave[i] = next;
}
}
return(wave);
}
/// <summary>
/// Creates basic audio waves
/// </summary>
/// <param name="waveType"></param>
/// <param name="waveAttributes"></param>
/// <returns></returns>
static public WaveChunk MakeWave(WaveTypes waveType, WaveAttributes waveAttributes)
{
switch (waveType)
{
case WaveTypes.SineWave:
return(MakeSineWave(waveAttributes));
case WaveTypes.Square:
return(MakeSquareWave(waveAttributes));
case WaveTypes.Sawtooth:
return(MakeSawtooth(waveAttributes));
case WaveTypes.Triangle:
return(MakeTriangle(waveAttributes));
case WaveTypes.WhiteNoise:
return(MakeWhiteNoise(waveAttributes));
default:
throw new ArgumentException("Not a valid wave type");
}
}
