I am trying to record the sound from the MIC and draw a live graph. I am able to record and draw the graph. The problem is the values that are recorded using the code below are not accurate for example ... the image below is what i get when there is no sound at all present. I have seen examples using the fft but I am noot sure if that will be of any help in my case as I am trying to draw a time domain graph and I see no purpose to convert it to frequency domain (for now). Others are using average power, this might be helpful but I am not sure.
Thanks for any help.
bufferSize = AudioRecord.getMinBufferSize(RECORDER_SAMPLERATE,RECORDER_CHANNELS,RECORDER_AUDIO_ENCODING);
recorder = new AudioRecord(MediaRecorder.AudioSource.MIC,
RECORDER_SAMPLERATE, RECORDER_CHANNELS,RECORDER_AUDIO_ENCODING, bufferSize);
short data [] = new short[bufferSize];
while (!Thread.interrupted()) {
recorder.startRecording();
recorder.read(data, 0, bufferSize);
recorder.stop();
for (short s : data)
{
try {
Thread.sleep((long) 300.00);
} catch (InterruptedException e) {
// TODO Auto-generated catch block
e.printStackTrace();
}
postUI (Math.abs(s));
}
}
recorder.release();
For anyone else looking for a way to do this, check out Samsung's fantastic example complete with source code