How do I make my animation smoother Android

Question

I have an app that has a ball running across the screen. When the ball is halfway the application records some audio, computes the FFT and does some extra analysis.

This is handled by Asynctask, however the animation still briefly stutters.

Does anyone have any suggestions on how to make it run smoother?

Thanks

code below:

import com.ben.applicationLayer.GameView;
import dataObjectLayer.Sprite;
import dataObjectLayer.MusicalNote;
import android.media.AudioRecord;
import android.media.MediaRecorder.AudioSource;
import android.media.AudioFormat; 
import android.os.AsyncTask;

public class recorderThread extends AsyncTask<Sprite, Void, Integer> {

short[] audioData;
int bufferSize;    
Sprite ballComp;

@Override
protected Integer doInBackground(Sprite... ball) {

    MusicalNote note = ball[0].expectedNote;
    ballComp = ball[0];
        boolean recorded = false; 
        double frequency;
        int sampleRate = 8192;  
        AudioRecord recorder = instatiateRecorder(sampleRate);
        double[] magnitude = new double[1024];
        double[] audioDataDoubles = new double[2048];

        while (!recorded) {  //loop until recording is running

        if (recorder.getState()==android.media.AudioRecord.STATE_INITIALIZED) 
// check to see if the recorder has initialized yet.
        {
            if (recorder.getRecordingState()==android.media.AudioRecord.RECORDSTATE_STOPPED)
                  recorder.startRecording();  
//check to see if the Recorder has stopped or is not recording, and make it record.                               
            else {             
               double max_index;
               recorder.read(audioData,0,bufferSize);   
//read the PCM audio data into the audioData array

               computeFFT(audioDataDoubles, magnitude);

               max_index = getLargestPeakIndex(magnitude);

               frequency = getFrequencyFromIndex(max_index, sampleRate);

            //checks if correct frequency, assigns number
               int correctNo = correctNumber(frequency, note);

checkIfMultipleNotes(correctNo, max_index, frequency, sampleRate, magnitude, note);

               if (audioDataIsNotEmpty())
                   recorded = true;
               if (correctNo!=1)
                   return correctNo;
              }
        }
        else
        {
            recorded = false;
            recorder = instatiateRecorder(sampleRate);
        }
    }

        if (recorder.getState()==android.media.AudioRecord.RECORDSTATE_RECORDING) 
        {
            killRecorder(recorder);
        }

        return 1;
}


private void killRecorder(AudioRecord recorder) {
    recorder.stop(); //stop the recorder before ending the thread
    recorder.release(); //release the recorders resources
    recorder=null; //set the recorder to be garbage collected
}

@Override
protected void onPostExecute(Integer result) {  
    (result == 2)
        GameView.score++;
    }

private AudioRecord instatiateRecorder(int sampleRate) {    
        bufferSize= AudioRecord.getMinBufferSize(sampleRate,AudioFormat.CHANNEL_CONFIGURATION_MONO,
                AudioFormat.ENCODING_PCM_16BIT)*2;
 //get the buffer size to use with this audio record

AudioRecord recorder = new AudioRecord (AudioSource.MIC,sampleRate, AudioFormat.CHANNEL_CONFIGURATION_MONO, AudioFormat.ENCODING_PCM_16BIT,bufferSize); //instantiate the AudioRecorder

    audioData = new short [bufferSize]; //short array that pcm data is put into.         
        return recorder;
}

}

Answer 1

Using an Asynctask is along the lines of what you want to do. However, I would suggest using a thread-pool. You can then put your animation in as a task, add your audio recording as a task, the FFT as another task, and your additional analysis as a task.

The brief stutter is likely the result of allocating resources for the recording in the animation thread. Using a pool means you won't have to pause while creating the thread to run your audio tasks. Obviously, some code would be handy to fully understand your problem.

Take a look at:

ScheduledThreadPoolExecutor http://docs.oracle.com/javase/6/docs/api/java/util/concurrent/ScheduledThreadPoolExecutor.html

or

ThreadPoolExecutor http://docs.oracle.com/javase/6/docs/api/java/util/concurrent/ThreadPoolExecutor.html

A very simple example of what you might want to do:

In your activity you can define this to start up the tasks

ExecutorService threadPool = new ScheduledThreadPoolExecutor(2);
Recording record = new Recording();
Ball ball = new Ball(threadPool, record);
threadPool.submit(ball);

Ball.java

import java.util.concurrent.ExecutorService;

public class Ball implements Runnable { 
    private final Recording record;
    private final ExecutorService threadPool;

    private boolean condition;  
    private boolean active;

    public Ball(ExecutorService threadPool, Recording record) {
        this.record = record;
        this.threadPool = threadPool;
        this.active = true;
    }

    @Override public void run() {
        while (this.active) {
            moveBall();
            if (isBallHalfway()) {
                threadPool.submit(record);
            }
        }
    }

    private boolean isBallHalfway() {
        return condition; // Condition for determining when ball is halfway
    }

    private void moveBall() {
        // Code to move the ball
    }
}

Recording.java

public class Recording implements Runnable {
    @Override public void run() {
        // Do recording tasks here
    }
}