/*Documentation
* Method: read
* Author: Josh Weese
* Purpose: Reads and processes audio capture memory stream
* Parameters:
* Returns:
* Notes: #reads audio capture memory stream
* #converts stream into usable data
* #saves data to txt file if option is checked
* #chunks data, converts it to complex numbers, runs FFT, and determines pitch and frequency
* ChangeLog: Version 1.0...5/3/2011--Documented
*/
public void read()
{
//make sure data reached the fft lenght thresh hold
if (audioSink.AudioData.Length >= Constants.fftLength)
{
//read the entire memory stream
audioSink.AudioData.Seek(seekPosition, SeekOrigin.Begin);
byte[] data = new byte[audioSink.AudioData.Length];
int chunkSize = 4096;
int numBytesToRead = (int)audioSink.AudioData.Length;
int numBytesRead = 0;
while (numBytesToRead > 0)
{
if (chunkSize + numBytesRead > data.Length)
{
chunkSize = data.Length - numBytesRead;
}
int n = audioSink.AudioData.Read(data, numBytesRead, chunkSize);
if (n == 0)
{
break;
}
numBytesRead += n;
numBytesToRead -= n;
}
//kill the buffer once read
audioSink.AudioData.Flush();
audioSink.AudioData.Dispose();
//re-initialize
audioSink.AudioData = new MemoryStream();
if (saveFile)
{
save(data);
}
//length of data
int length;
Int16[] int16Data;
int y = 0;
int z = 0;
//convert raw data to useable numbers
if (audioSink.AudioFormat.BitsPerSample == 16)
{
length = data.Length / 2;
int16Data = new Int16[length];
if (BitConverter.IsLittleEndian)
{
Array.Reverse(data);
}
for (int i = 0; i < length; i += 2)
{
if (!(i > data.Length))
{
int16Data[z] = BitConverter.ToInt16(data, i);
}
else
{
int16Data[z] = 0;
}
z++;
}
}
else
{
length = data.Length;
int16Data = new Int16[length];
for (int i = 0; i < length; i++)
{
int16Data[i] = data[i];
}
}
if (saveFile)
{
save(int16Data);
}
z = 0;
//chunk audio data to feed to FFT and calculate freqency
while (true)
{
//chunk
int max;
if (length > Constants.fftLength)
{
max = Constants.fftLength;
}
else
{
if (IsPowerOfTwo((ulong)length))
{
max = length;
}
else
{
break;
}
}
//convert to complex numbers
ComplexNumber[] complexData1 = new ComplexNumber[max];
y = 0;
while (y < max)
{
complexData1[y] = new ComplexNumber(int16Data[z] / Constants.downsample);
y++;
z++;
}
//run fft
ComplexNumber[] fft1 = ft.FFT(complexData1, FourierTransform.Direction.Forward);
if (saveFile)
{
save(fft1);
}
//retrieve pitch
pitch = frequency.getPitch(fundFreq.fundamentalFreq, pitchList);
//frequency
fundFreq.fundamentalFreq = frequency.calcFundamentalFreq(fft1, audioSink.AudioFormat.SamplesPerSecond);
//cents
fundFreq.cents = frequency.calculateCents(fundFreq.fundamentalFreq, pitch.fundamentalFreq);
//actual note
fundFreq.note = pitch.note;
//accidental
fundFreq.accidental = pitch.accidental;
if ((length -= max) == 0)
{
break;
}
}
}
}
/*Documentation
* Method: manualFrequency
* Author: Josh Weese
* Purpose: Calculates the freqeuncy based on user input
* Parameters:
* Returns:
* Notes:
* #This method is ment for accuracy testing
* #creates a sine wave based on the input frequency and sample count
* #converts to complex numbers
* #runs fft and calculates pitch
* ChangeLog: Version 1.0...5/3/2011--Documented
*/
private void manualFrequency(double freq, int sampleCount, int sampleRate)
{
//create sine wave
double increment = (double)(2 * Math.PI) * freq / sampleRate;
double angle = 0;
double[] samples = new double[sampleCount];
for (int i = 0; i < samples.Length; i++)
{
samples[i] = ((double)Math.Sin(angle));
angle += increment;
}
if ((bool)saveCheck.IsChecked)
{
save(samples);
}
//convert to complex numbers
ComplexNumber[] complexData1 = new ComplexNumber[sampleCount];
int y = 0;
while (y < sampleCount)
{
complexData1[y] = new ComplexNumber(samples[y]);
y++;
}
//run fft
ComplexNumber[] fft1 = ft.FFT(complexData1, FourierTransform.Direction.Forward);
if ((bool)saveCheck.IsChecked)
{
save(fft1);
}
//frequency
fundFreq.fundamentalFreq = frequency.calcFundamentalFreq(fft1, sampleRate);
//get pitch
pitch = frequency.getPitch(fundFreq.fundamentalFreq, pitchList);
//cents
fundFreq.cents = frequency.calculateCents(fundFreq.fundamentalFreq, pitch.fundamentalFreq);
//actual note
fundFreq.note = pitch.note;
//accidental
fundFreq.accidental = pitch.accidental;
}
/*Documentation
* Method: loadPitches
* Author: Josh Weese
* Purpose: Calculates all pitches (sharps and fundamental) from concert pitch
* Parameters: #double concertAfreq...concert pitch to base notes from
* #List<Pitch> pitchList...pitch list to store in
* Returns: List<Pitch> pitchList
* Notes: #B and E have no sharp note
* ChangeLog: Version 1.0...5/3/2011--Documented
*/
public List<Pitch> loadPitches(double concertAfreq, List<Pitch> pitchList)
{
PitchConstants pConstants = new PitchConstants();
pitchList = new List<Pitch>();
int x = 3;
int z = 0;
bool y = true;
for (int i = -33; i < 27; i++)
{
Pitch pitch = new Pitch();
//frequency
pitch.fundamentalFreq = concertAfreq * (Math.Pow(2.0, (i / 12.0)));
//accidentals
if (y)
{
switch (z)
{
case 0:
pitch.accidental = pConstants.natural;
z++;
break;
case 1:
pitch.accidental = pConstants.sharp;
z = 0;
break;
default:
break;
}
}
else
{
pitch.accidental = pConstants.natural;
}
//note
switch (x)
{
case 1:
pitch.note = pConstants.A;
y = true;
break;
case 2:
pitch.note = pConstants.B;
y = false;
break;
case 3:
pitch.note = pConstants.C;
y = true;
break;
case 4:
pitch.note = pConstants.D;
y = true;
break;
case 5:
pitch.note = pConstants.E;
y = false;
break;
case 6:
pitch.note = pConstants.F;
y = true;
break;
case 7:
pitch.note = pConstants.G;
y = true;
break;
default:
x = 1;
break;
}
if (pitch.accidental == pConstants.sharp || !y)
{
x++;
if (x == 8)
{
x = 1;
}
}
pitchList.Add(pitch);
}
return pitchList;
}
