Android app - Skipped frames in pitch recognition

Question

I'm working on a note recognition software, and, I use a Thread.sleep to ensure a pitch is consistent enough over a period to qualify as a note rather than noise. This seems to be making my app skip frames though, and pretty much breaks the program. How can I avoid this?

package com.example.miguel.guitartab;

import be.tarsos.dsp.AudioDispatcher;
import be.tarsos.dsp.AudioEvent;
import be.tarsos.dsp.io.android.AudioDispatcherFactory;
import be.tarsos.dsp.pitch.PitchDetectionHandler;
import be.tarsos.dsp.pitch.PitchDetectionResult;
import be.tarsos.dsp.pitch.PitchProcessor;
import be.tarsos.dsp.pitch.PitchProcessor.PitchEstimationAlgorithm;

import android.content.res.ColorStateList;
import android.os.Bundle;
import android.support.v4.app.Fragment;
import android.support.v7.app.ActionBarActivity;
import android.view.LayoutInflater;
import android.view.Menu;
import android.view.MenuItem;
import android.view.View;
import android.view.ViewGroup;
import android.widget.TextView;

public class MainActivity extends ActionBarActivity {
    private Song song = new Song();
    private boolean finished = false;

    @Override
    protected void onCreate(Bundle savedInstanceState) {
        super.onCreate(savedInstanceState);
        setContentView(R.layout.activity_tarsos_dsp);
        AudioDispatcher dispatcher = AudioDispatcherFactory
                                        .fromDefaultMicrophone(22050,1024,0);



        dispatcher.addAudioProcessor(new PitchProcessor(PitchEstimationAlgorithm.FFT_YIN, 22050, 1024, new PitchDetectionHandler() {

            @Override
            public void handlePitch(final PitchDetectionResult pitchDetectionResult,
                                    AudioEvent audioEvent) {
                runOnUiThread(new Runnable() {
                    @Override
                    public void run() {
                        final float pitch = pitchDetectionResult.getPitch();
                        TextView text = (TextView) findViewById(R.id.textView1);
                        text.setText("" + pitch);

                        if (pitch>700) {
                            song = new Song();
                            finished = false;
                        } else if (finished){
                            text.setText("Song finished");
                        } else {
                            try{
                                Thread.sleep(80);
                            } catch (InterruptedException e) {
                                e.printStackTrace();
                            }
                            float pitch2 = pitchDetectionResult.getPitch();
                            if (pitch * 0.99 < pitch2 && pitch * 1.01 > pitch2) {
                                if (pitch + 2 > song.notes.get(0) && pitch - 2 < song.notes.get(0)) {
                                    System.out.println("Found pitch: " +song.notes.get(0));
                                    text.setTextColor(0xFF00FF00);
                                    song.notes.remove(0);
                                    if (song.notes.size()==0){
                                        finished = true;
                                        text.setTextColor(0xFFFF0000);
                                    }
                                } else {
                                    if (finished = true){
                                        text.setTextColor(0xFFFF0000);
                                    } else {
                                        text.setTextColor(0xFF00FF00);
                                    }

                                }
                            }
                        }
                    }
                });

            }
        }));
        new Thread(dispatcher,"Audio Dispatcher").start();

    }

    @Override
    public void onBackPressed()
    {
        moveTaskToBack(true);
    }
    @Override
    public boolean onCreateOptionsMenu(Menu menu) {
        // Inflate the menu; this adds items to the action bar if it is present.
        getMenuInflater().inflate(R.menu.tarsos_ds, menu);
        return true;
    }

    @Override
    public boolean onOptionsItemSelected(MenuItem item) {
        // Handle action bar item clicks here. The action bar will
        // automatically handle clicks on the Home/Up button, so long
        // as you specify a parent activity in AndroidManifest.xml.
        int id = item.getItemId();
        if (id == R.id.action_settings) {
            return true;
        }
        return super.onOptionsItemSelected(item);
    }

    /**
     * A placeholder fragment containing a simple view.
     */
    public static class PlaceholderFragment extends Fragment {

        public PlaceholderFragment() {
        }

        @Override
        public View onCreateView(LayoutInflater inflater, ViewGroup container,
                                 Bundle savedInstanceState) {
            View rootView = inflater.inflate(R.layout.fragment_tarsos_ds,
                    container, false);
            return rootView;
        }
    }
}