Android噪音检测系统

Android噪音检测系统是基于手机声音获取接口来获取声音分贝值，通过分贝值画出分贝曲线，这是给一个学姐做的毕设，，先看看效果吧！


分贝曲线图通过移动原理可实现左右移动，效果还可以吧！花一天时间完成的，
下面来看看核心代码吧！

package com.fb.fragment;

import java.util.Timer;

import org.achartengine.GraphicalView;

import android.R.integer;
import android.R.string;
import android.annotation.SuppressLint;
import android.graphics.Color;
import android.os.Handler;
import android.provider.MediaStore.Audio.Media;
import android.util.Log;
import android.view.View;
import android.view.View.OnClickListener;
import android.view.animation.Animation;
import android.view.animation.RotateAnimation;
import android.widget.Button;
import android.widget.ImageView;
import android.widget.LinearLayout;
import android.widget.TextView;
import android.widget.RelativeLayout.LayoutParams;

import com.example.blaudios.R;
import com.fb.activity.MainActivity;
import com.fb.base.BaseFragment;
import com.fb.util.BewriteUtil;
import com.fb.util.FbChartline;
import com.fb.util.MyMediaRecorder;
import com.fb.util.SuggestUtil;
import com.lidroid.xutils.ViewUtils;
import com.lidroid.xutils.view.annotation.ViewInject;
/**
 * 
 * @author 曲线页面
 *
 */
public class CurveFragment extends BaseFragment implements OnClickListener{
    @ViewInject(R.id.left_temperature_curve)
    private LinearLayout left_temperature_curve;
    @ViewInject(R.id.title_textview)
    private TextView title_textview;
    @ViewInject(R.id.text_bewrite)
    private TextView text_bewrite;//环境描述
    @ViewInject(R.id.text_suggest)
    private TextView text_suggest;//对应环境下面的建议
    private GraphicalView  mView;
    private FbChartline mService;
    //private MyAudioRecord audioRecordDemo ;
    private MyMediaRecorder media;
    @ViewInject(R.id.lsschj)
    private TextView lsschj;
    @ViewInject(R.id.text_vip)//噪音等级
    private TextView text_vip;

    @ViewInject(R.id.text_decibel)
    private TextView text_decibel;
    @ViewInject(R.id.needle)
    private ImageView needleView;  //指针图片
    @ViewInject(R.id.bt_start)
    private Button    bt_start;

    private float     degree = 0.0f;  //记录指针旋转
    private boolean   is_start=true;
    @Override
    public void initData() {
        bt_start.setOnClickListener(this);
        //audioRecordDemo =new MyAudioRecord(handler);
        media=new MyMediaRecorder(handler);
    }

    @Override
    public View initView() {
        view=View.inflate(context, R.layout.fragment_main, null);
        ViewUtils.inject(this,view);
        title_textview.setText("噪音测试仪");
        bt_start.setText("开始测试");
        setChartLineView();
        return view;
    }
    @SuppressWarnings("deprecation")
    private void setChartLineView() {
        mService=new FbChartline(context);
        mService.setXYMultipleSeriesDataset("分贝图");
        mService.setXYMultipleSeriesRenderer(100, 100, "分贝图", "时间", "分贝数值",
                Color.BLACK, Color.BLACK, Color.RED, Color.BLACK);
        mView = mService.getGraphicalView();
        left_temperature_curve.addView(mView, new LayoutParams(
                LayoutParams.FILL_PARENT, LayoutParams.MATCH_PARENT));      
    }
    private int t = 0;
    @SuppressLint("HandlerLeak")
    BewriteUtil bewriteUtil=new BewriteUtil();
    SuggestUtil suggestUtil=new SuggestUtil();

    Handler handler=new Handler(){

        @SuppressLint("HandlerLeak")
        public void handleMessage(android.os.Message msg) {
            switch (msg.what) {
            case 0X00:
                if ("-Infinity".equals( msg.obj.toString())) {
                    degree=0f;
                }else {
                    degree =(Float.parseFloat( msg.obj.toString()));//获取到的值
                }

                mService.updateChart(t, degree);
                t+=5;
                Log.i("传递过来的参数", msg.obj.toString());
                //degree =(Float)msg.obj;
                //t+=1;
                String subString="";
                //数据采集格式化
                if (degree>100) {
                    subString=String.valueOf(degree).substring(0, 3);
                }
                if (degree<10) {
                    subString=String.valueOf(degree).substring(0, 1);

                }if (degree>10&°ree<100) {
                    subString=String.valueOf(degree).substring(0, 2);
                } 
                if (degree<0) {
                    subString="0";
                }
                text_decibel.setText(subString+" dB");
                if (degree>60) {
                    text_decibel.setTextColor(Color.RED);
                    text_bewrite.setTextColor(Color.RED);
                    text_suggest.setTextColor(Color.RED);
                }else {
                    text_suggest.setTextColor(Color.BLACK);
                    text_bewrite.setTextColor(Color.BLACK);
                    text_decibel.setTextColor(Color.WHITE);
                }

                Integer integer=Integer.parseInt(subString);

                String bweString=bewriteUtil.goBewrite(integer);
                int vip=bewriteUtil.getVip(integer);
                text_vip.setText("噪音:"+vip+"等级");
                String suggString= suggestUtil.getSuggsetByDb(integer);
            text_suggest.setText(suggString);
                text_bewrite.setText(bweString);
                RotateAnimation animation = new RotateAnimation(degree, 
                        degree, Animation.RELATIVE_TO_SELF, 0.5f,
                        Animation.RELATIVE_TO_SELF, 0.5f);
                animation.setDuration(1000);
                animation.setFillAfter(true);
                needleView.startAnimation(animation);
                break;
            default:
                break;
            }
        }
    };

    @Override
    public  void onClick(View v) {
        switch (v.getId()) {
        case R.id.bt_start:
            if (is_start) {
                bt_start.setText("停止测试");

                media.startRecord();
                is_start=false;
            }else {
                bt_start.setText("开始测试");
                media.stopRecord();
            is_start=true;
            }
            break;

        default: 
            break;
        }
    }
}

获取分贝值得方法：

package com.fb.util;


import java.io.File;
import java.io.IOException;


import android.media.MediaRecorder;
import android.os.Handler;
import android.os.Message;
import android.util.Log;



public class MyMediaRecorder {
  private final String TAG = "MediaRecord";
  private MediaRecorder mMediaRecorder;
  public static final int MAX_LENGTH = 1000 * 60 * 10;// 最大录音时长1000*60*10;
  private String filePath;
  private Handler handler = new Handler();
  public MyMediaRecorder(Handler handler){
    this.filePath = "/dev/null";
    this.handler=handler;
  }
  public MyMediaRecorder(File file) {
    this.filePath = file.getAbsolutePath();
  }
  private long startTime;
  private long endTime;
  public void startRecord() {
    if (mMediaRecorder == null)
      mMediaRecorder = new MediaRecorder();
    try {
      mMediaRecorder.setAudioSource(MediaRecorder.AudioSource.MIC);
      mMediaRecorder.setOutputFormat(MediaRecorder.OutputFormat.DEFAULT);
      mMediaRecorder.setAudioEncoder(MediaRecorder.AudioEncoder.AMR_NB);
       mMediaRecorder.setOutputFile(filePath);
      mMediaRecorder.setMaxDuration(MAX_LENGTH);
      mMediaRecorder.prepare();
      mMediaRecorder.start();
      startTime = System.currentTimeMillis();
      updateMicStatus();
    } catch (IllegalStateException e) {

    } catch (IOException e) {

    }
  }

  /**
   * 停止录音
   *
   */
  public long stopRecord() {
    if (mMediaRecorder == null)
      return 0L;
    endTime = System.currentTimeMillis();
    Log.i("ACTION_END", "endTime" + endTime);
    mMediaRecorder.stop();
    mMediaRecorder.reset();
    mMediaRecorder.release();
    mMediaRecorder = null;
    Log.i("ACTION_LENGTH", "Time" + (endTime - startTime));
    return endTime - startTime;
  }


  private Runnable mUpdateMicStatusTimer = new Runnable() {
    public void run() {
      updateMicStatus();
    }
  };

  /**
   * 更新话筒状态
   *
   */
  private int BASE = 1;
  private int SPACE = 100;// 间隔取样时间

  private void updateMicStatus() {
    if (mMediaRecorder != null) {
      double ratio = (double)mMediaRecorder.getMaxAmplitude() /BASE;
      double db = 0;// 分贝
      if (ratio > 1)
        db = (20 * Math.log10(ratio))*0.7;
      Message message =Message.obtain();
      message.what=0X00;
      message.obj=db;
      handler.sendMessage(message);
      Log.d(TAG,"分贝值："+db);
      handler.postDelayed(mUpdateMicStatusTimer, SPACE);
    }
  }
}

原理其实很简单，需要源码的小伙伴留下邮箱