Welcome to OStack Knowledge Sharing Community for programmer and developer-Open, Learning and Share
Welcome To Ask or Share your Answers For Others

Categories

0 votes
734 views
in Technique[技术] by (71.8m points)

audio - Decibel Sound Meter for Android

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.

See Question&Answers more detail:os

与恶龙缠斗过久,自身亦成为恶龙;凝视深渊过久,深渊将回以凝视…
Welcome To Ask or Share your Answers For Others

1 Answer

0 votes
by (71.8m points)

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


与恶龙缠斗过久,自身亦成为恶龙;凝视深渊过久,深渊将回以凝视…
Welcome to OStack Knowledge Sharing Community for programmer and developer-Open, Learning and Share
Click Here to Ask a Question

...