Graphing the pitch (frequency) of a sound
- by Coronatus
I want to plot the pitch of a sound into a graph.
Currently I can plot the amplitude. The graph below is created by the data returned by getUnscaledAmplitude():
AudioInputStream audioInputStream = AudioSystem.getAudioInputStream(new BufferedInputStream(new FileInputStream(file)));
byte[] bytes = new byte[(int) (audioInputStream.getFrameLength()) * (audioInputStream.getFormat().getFrameSize())];
audioInputStream.read(bytes);
// Get amplitude values for each audio channel in an array.
graphData = type.getUnscaledAmplitude(bytes, this);
public int[][] getUnscaledAmplitude(byte[] eightBitByteArray, AudioInfo audioInfo)
{
int[][] toReturn = new int[audioInfo.getNumberOfChannels()][eightBitByteArray.length / (2 * audioInfo.
getNumberOfChannels())];
int index = 0;
for (int audioByte = 0; audioByte < eightBitByteArray.length;)
{
for (int channel = 0; channel < audioInfo.getNumberOfChannels(); channel++)
{
// Do the byte to sample conversion.
int low = (int) eightBitByteArray[audioByte];
audioByte++;
int high = (int) eightBitByteArray[audioByte];
audioByte++;
int sample = (high << 8) + (low & 0x00ff);
if (sample < audioInfo.sampleMin)
{
audioInfo.sampleMin = sample;
}
else if (sample > audioInfo.sampleMax)
{
audioInfo.sampleMax = sample;
}
toReturn[channel][index] = sample;
}
index++;
}
return toReturn;
}
But I need to show the audio's pitch, not amplitude. Fast Fourier transform appears to get the pitch, but it needs to know more variables than the raw bytes I have, and is very complex and mathematical.
Is there a way I can do this?
