2021-05-03

**

利用android自带的人脸识别进行识别，标记出眼睛和人脸位置。点击button后进行人脸识别，完毕后显示到imageview上。

**package org.yanzi.testfacedetect;

import org.yanzi.util.ImageUtil;
import org.yanzi.util.MyToast;

import android.app.Activity;
import android.graphics.Bitmap;
import android.graphics.Bitmap.Config;
import android.graphics.BitmapFactory;
import android.graphics.Canvas;
import android.graphics.Color;
import android.graphics.Paint;
import android.graphics.Point;
import android.graphics.PointF;
import android.graphics.Rect;
import android.media.FaceDetector;
import android.media.FaceDetector.Face;
import android.os.Bundle;
import android.os.Handler;
import android.os.Message;
import android.util.DisplayMetrics;
import android.util.Log;
import android.view.Menu;
import android.view.View;
import android.view.View.OnClickListener;
import android.view.ViewGroup;
import android.view.ViewGroup.LayoutParams;
import android.widget.Button;
import android.widget.ImageView;
import android.widget.ProgressBar;
import android.widget.RelativeLayout;

public class MainActivity extends Activity {
static final String tag = “yan”;
ImageView imgView = null;
FaceDetector faceDetector = null;
FaceDetector.Face[] face;
Button detectFaceBtn = null;
final int N_MAX = 2;
ProgressBar progressBar = null;

Bitmap srcImg = null;
Bitmap srcFace = null;
Thread checkFaceThread = new Thread(){

    @Override
    public void run() {
        // TODO Auto-generated method stub
        Bitmap faceBitmap = detectFace();
        mainHandler.sendEmptyMessage(2);
        Message m = new Message();
        m.what = 0;
        m.obj = faceBitmap;
        mainHandler.sendMessage(m);
        
    }

};
 Handler mainHandler = new Handler(){

    @Override
    public void handleMessage(Message msg) {
        // TODO Auto-generated method stub
        //super.handleMessage(msg);
        switch (msg.what){
        case 0:
            Bitmap b = (Bitmap) msg.obj;
            imgView.setImageBitmap(b);
            MyToast.showToast(getApplicationContext(), "检测完毕");
            break;
        case 1:
            showProcessBar();
            break;
        case 2:
            progressBar.setVisibility(View.GONE);
            detectFaceBtn.setClickable(false);
            break;
        default:
            break;
        }
    }

};
@Override
protected void onCreate(Bundle savedInstanceState) {
    super.onCreate(savedInstanceState);
    setContentView(R.layout.activity_main);
    initUI(); 
    initFaceDetect();
    detectFaceBtn.setOnClickListener(new OnClickListener() {

        @Override
        public void onClick(View v) {
            // TODO Auto-generated method stub
            mainHandler.sendEmptyMessage(1);
            checkFaceThread.start();
            
        }
    });



}

@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;
}
public void initUI(){

    detectFaceBtn = (Button)findViewById(R.id.btn_detect_face);
    imgView = (ImageView)findViewById(R.id.imgview);
    LayoutParams params = imgView.getLayoutParams();
    DisplayMetrics dm = getResources().getDisplayMetrics();
    int w_screen = dm.widthPixels;
    //        int h = dm.heightPixels;

    srcImg = BitmapFactory.decodeResource(getResources(), R.drawable.kunlong);
    int h = srcImg.getHeight();
    int w = srcImg.getWidth();
    float r = (float)h/(float)w;
    params.width = w_screen;
    params.height = (int)(params.width * r);
    imgView.setLayoutParams(params);
    imgView.setImageBitmap(srcImg);
}

public void initFaceDetect(){
    this.srcFace = srcImg.copy(Config.RGB_565, true);
    int w = srcFace.getWidth();
    int h = srcFace.getHeight();
    Log.i(tag, "待检测图像: w = " + w + "h = " + h);
    faceDetector = new FaceDetector(w, h, N_MAX);
    face = new FaceDetector.Face[N_MAX];
}
public boolean checkFace(Rect rect){
    int w = rect.width();
    int h = rect.height();
    int s = w*h;
    Log.i(tag, "人脸 宽w = " + w + "高h = " + h + "人脸面积 s = " + s);
    if(s < 10000){
        Log.i(tag, "无效人脸，舍弃.");
        return false;
    }
    else{
        Log.i(tag, "有效人脸，保存.");
        return true;    
    }
}
public Bitmap detectFace(){
    //        Drawable d = getResources().getDrawable(R.drawable.face_2);
    //        Log.i(tag, "Drawable尺寸 w = " + d.getIntrinsicWidth() + "h = " + d.getIntrinsicHeight());
    //        BitmapDrawable bd = (BitmapDrawable)d;
    //        Bitmap srcFace = bd.getBitmap();

    int nFace = faceDetector.findFaces(srcFace, face);
    Log.i(tag, "检测到人脸：n = " + nFace);
    for(int i=0; i

}