关于安卓visualizer的用法

看别人显示播放wav文件显示频谱写的代码都是断断续续的，在这里我贴了完整的代码，给有需要的人做参考，显示频谱还没有完成，不知道怎么弄，已经可以得到byte[] fft数据了，参考别人的写法也可以开方取模了，但是就是耗在了byte[]转doule[]上了，因为我用achartEngine画图的，所以现在还没有解决办法，有谁知道的，请在给我留言，谢谢。下面上代码，布局文件就不贴了，很简单的就是两个按钮

package com.example.visualizer;

import android.app.Activity;
import android.media.MediaPlayer;
import android.media.audiofx.Visualizer;
import android.net.Uri;
import android.os.Bundle;
import android.os.Environment;
import android.view.Menu;
import android.view.MenuItem;
import android.view.View;
import android.widget.Button;

public class MainActivity extends Activity {
	private MediaPlayer mediaPlayer;
	private Visualizer visualizer;
	Button playButton, stopButton;
	Uri pathUri;

	@Override
	protected void onCreate(Bundle savedInstanceState) {
		super.onCreate(savedInstanceState);
		setContentView(R.layout.activity_main);
		playButton = (Button) findViewById(R.id.button1);
		stopButton = (Button) findViewById(R.id.button2);
		playButton.setOnClickListener(listener);
		stopButton.setOnClickListener(listener);
		pathUri = Uri.parse(Environment.getExternalStorageDirectory().getPath()
				+ "/heartBit.wav");
		System.out.println(pathUri);
		mediaPlayer = MediaPlayer.create(this, pathUri);
		visualizer = new Visualizer(mediaPlayer.getAudioSessionId());
		visualizer.setCaptureSize(Visualizer.getCaptureSizeRange()[1]);
		System.out.println(Visualizer.getCaptureSizeRange()[1]);
		visualizer.setDataCaptureListener(
				new Visualizer.OnDataCaptureListener() {

					@Override
					public void onWaveFormDataCapture(Visualizer arg0,
							byte[] arg1, int arg2) {
						// TODO Auto-generated method stub

					}

					@Override
					public void onFftDataCapture(Visualizer arg0, byte[] fft,
							int arg2) {//返回的经过FFT处理后的数据
						// TODO Auto-generated method stub
						try {
							System.out.println(DataFix.getHexString(fft));
						} catch (Exception e) {
							// TODO Auto-generated catch block
							e.printStackTrace();
						}
					}
				}, Visualizer.getMaxCaptureRate() / 2, false, true);
		visualizer.setEnabled(true);//这步不能忘记
		mediaPlayer
				.setOnCompletionListener(new MediaPlayer.OnCompletionListener() {//监听器

					@Override
					public void onCompletion(MediaPlayer arg0) {
						// TODO Auto-generated method stub
						visualizer.setEnabled(false);
					}
				});
	}

	View.OnClickListener listener = new View.OnClickListener() {

		@Override
		public void onClick(View arg0) {
			// TODO Auto-generated method stub
			switch (arg0.getId()) {
			case R.id.button1:
				mediaPlayer.start();

				break;
			case R.id.button2:
				mediaPlayer.pause();

				break;
			default:
				break;
			}
		}
	};

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

开方取模的处理方法，参考别人的代码：

byte[] model = new byte[fft.length / 2 + 1];

		model[0] = (byte) Math.abs(fft[0]);
		for (int i = 2, j = 1; j < mSpectrumNum;) {
			model[j] = (byte) Math.hypot(fft[i], fft[i + 1]);
			i += 2;
			j++;
		}

到这里返回的还是byte[]数组，话说java下的转型相当麻烦，还不知道怎么解决！