I am new to Android and looking to write an app for measuring decibel sound level. The idea is that when a sound reaches a certain level the user gets a alert. That's it. Can anyone help me out with this. Can I do this using HTML5/Javascript ? any help will be appreciated.
Taken from Android Media Player Decibel Reading
For native android/java based decibel calculation for a MediaRecorder:
mRecorder = new MediaRecorder();
mRecorder.setAudioSource(MediaRecorder.AudioSource.MIC);
mRecorder.setOutputFormat(MediaRecorder.OutputFormat.THREE_GPP);
mRecorder.setAudioEncoder(MediaRecorder.AudioEncoder.AMR_NB);
mRecorder.setOutputFile("/dev/null");
mRecorder.prepare();
mRecorder.start();
public double getAmplitude() {
if (mRecorder != null)
return (mRecorder.getMaxAmplitude());
else
return 0;
}
To calculate Db value :
powerDb = 20 * log10(getAmplitude() / referenceAmp);
Reference: http://en.wikipedia.org/wiki/Decibel#Field_quantities
Not sure if you could do this in HTML5 on android