public WaveGenerator(IEnumerable <Note> notes)
{
// Init chunks
header = new WaveHeader();
format = new WaveFormatChunk();
data = new WaveDataChunk();
var milliseconds = notes.Select((x) => x.Duration.TotalMilliseconds).Sum();
//var seconds = (uint)(milliseconds / 1000);
// Number of samples = sample rate * channels * bytes per sample
// Multiply first, then divide to avoid rounding errors
uint numSamples = (uint)(((format.dwSamplesPerSec * milliseconds) / 1000) * format.wChannels);
// Initialize the 16-bit array
data.shortArray = new short[numSamples];
int amplitude = 32760; // Max amplitude for 16-bit audio
uint sampleCount = 0;
foreach (var n in notes)
{
// The "angle" used in the function, adjusted for the number of channels and sample rate.
// This value is like the period of the wave.
double t = (Math.PI * 2 * n.Frequency) / (format.dwSamplesPerSec * format.wChannels);
var samplesThisNote = format.dwSamplesPerSec * format.wChannels * n.Duration.TotalSeconds;
// Loop over sampleCount rather than from 0, because you don't want to reset
// the sine wave for repeated notes of the same pitch
for (uint i = sampleCount; i < (samplesThisNote + sampleCount) - 1; i++)
{
// Fill with a simple sine wave at max amplitude
for (int channel = 0; channel < format.wChannels; channel++)
{
data.shortArray[i + channel] = Convert.ToInt16(amplitude * Math.Sin(t * i));
}
}
sampleCount += (uint)samplesThisNote;
}
// Calculate data chunk size in bytes
data.dwChunkSize = (uint)(data.shortArray.Length * (format.wBitsPerSample / 8));
}
/// <summary>
/// Initializes the object and generates a wave.
/// </summary>
/// <param name="type">The type of wave to generate</param>
public WaveGenerator(WaveExampleType type, double freq, uint seconds)
{
// Init chunks
header = new WaveHeader();
format = new WaveFormatChunk();
data = new WaveDataChunk();
// Fill the data array with sample data
switch (type)
{
case WaveExampleType.ExampleSineWave:
// Number of samples = sample rate * channels * bytes per sample
uint numSamples = format.dwSamplesPerSec * format.wChannels * seconds;
// Initialize the 16-bit array
data.shortArray = new short[numSamples];
int amplitude = 32760; // Max amplitude for 16-bit audio
// The "angle" used in the function, adjusted for the number of channels and sample rate.
// This value is like the period of the wave.
double t = (Math.PI * 2 * freq) / (format.dwSamplesPerSec * format.wChannels);
for (uint i = 0; i < numSamples - 1; i++)
{
// Fill with a simple sine wave at max amplitude
for (int channel = 0; channel < format.wChannels; channel++)
{
data.shortArray[i + channel] = Convert.ToInt16(amplitude * Math.Sin(t * i));
}
}
// Calculate data chunk size in bytes
data.dwChunkSize = (uint)(data.shortArray.Length * (format.wBitsPerSample / 8));
break;
}
}
/// <summary>
/// Initializes the object and generates a wave.
/// </summary>
/// <param name="type">The type of wave to generate</param>
public WaveGenerator(WaveExampleType type, double freq, uint seconds)
{
// Init chunks
header = new WaveHeader();
format = new WaveFormatChunk();
data = new WaveDataChunk();
// Fill the data array with sample data
switch (type)
{
case WaveExampleType.ExampleSineWave:
// Number of samples = sample rate * channels * bytes per sample
uint numSamples = format.dwSamplesPerSec * format.wChannels * seconds;
// Initialize the 16-bit array
data.shortArray = new short[numSamples];
int amplitude = 32760; // Max amplitude for 16-bit audio
// The "angle" used in the function, adjusted for the number of channels and sample rate.
// This value is like the period of the wave.
double t = (Math.PI * 2 * freq) / (format.dwSamplesPerSec * format.wChannels);
for (uint i = 0; i < numSamples - 1; i++)
{
// Fill with a simple sine wave at max amplitude
for (int channel = 0; channel < format.wChannels; channel++)
{
data.shortArray[i + channel] = Convert.ToInt16(amplitude * Math.Sin(t * i));
}
}
// Calculate data chunk size in bytes
data.dwChunkSize = (uint)(data.shortArray.Length * (format.wBitsPerSample / 8));
break;
}
}
public WaveGenerator(IEnumerable<Note> notes)
{
// Init chunks
header = new WaveHeader();
format = new WaveFormatChunk();
data = new WaveDataChunk();
var milliseconds = notes.Select((x) => x.Duration.TotalMilliseconds).Sum();
//var seconds = (uint)(milliseconds / 1000);
// Number of samples = sample rate * channels * bytes per sample
// Multiply first, then divide to avoid rounding errors
uint numSamples = (uint)(((format.dwSamplesPerSec * milliseconds) / 1000) * format.wChannels);
// Initialize the 16-bit array
data.shortArray = new short[numSamples];
int amplitude = 32760; // Max amplitude for 16-bit audio
uint sampleCount = 0;
foreach (var n in notes)
{
// The "angle" used in the function, adjusted for the number of channels and sample rate.
// This value is like the period of the wave.
double t = (Math.PI * 2 * n.Frequency) / (format.dwSamplesPerSec * format.wChannels);
var samplesThisNote = format.dwSamplesPerSec * format.wChannels * n.Duration.TotalSeconds;
// Loop over sampleCount rather than from 0, because you don't want to reset
// the sine wave for repeated notes of the same pitch
for (uint i = sampleCount; i < (samplesThisNote + sampleCount) - 1; i++)
{
// Fill with a simple sine wave at max amplitude
for (int channel = 0; channel < format.wChannels; channel++)
{
data.shortArray[i + channel] = Convert.ToInt16(amplitude * Math.Sin(t * i));
}
}
sampleCount += (uint)samplesThisNote;
}
// Calculate data chunk size in bytes
data.dwChunkSize = (uint)(data.shortArray.Length * (format.wBitsPerSample / 8));
}
