Android+opencv实时人脸与人眼检测案例分享

软件版本：

Android Studio Electric Eel 2022.1.1 Patch 2

https://sourceforge.net/projects/opencvlibrary/files/4.5.0/opencv-4.5.0-android-sdk.zip/download

创建工程并导入opencv sdk:

导入opencv sdk:
File->New->Import Module

添加工程依赖：File->Project Structure， sdk为opencv sdk.

导入人脸和人眼检测训练模型

haarcascade_eye_tree_eyeglasses.xml
lbpcascade_frontalface_improved.xml

activity_main.xml

<?xml version="1.0" encoding="utf-8"?>

<org.opencv.android.JavaCameraViewandroid:id="@+id/camera_view"android:layout_height="match_parent"android:layout_width="match_parent"android:layout_weight="1"/><Buttonandroid:layout_width="37dp"android:layout_height="37dp"android:layout_margin="10dp"android:layout_gravity="center_vertical"android:background="@mipmap/ic_launcher"android:id="@+id/switchCamera"/>

AndroidManifest.xml

<?xml version="1.0" encoding="utf-8"?>

<applicationandroid:allowBackup="true"android:dataExtractionRules="@xml/data_extraction_rules"android:fullBackupContent="@xml/backup_rules"android:icon="@mipmap/ic_launcher"android:label="@string/app_name"android:supportsRtl="true"android:theme="@style/Theme.Facedetectwithcamera"tools:targetApi="31"><activityandroid:name=".MainActivity"android:exported="true"><intent-filter><action android:name="android.intent.action.MAIN" /><category android:name="android.intent.category.LAUNCHER" /></intent-filter></activity>
</application>

MainActivity

package com.michael.facedetectwithcamera;

import androidx.appcompat.app.AppCompatActivity;
import androidx.core.app.ActivityCompat;
import androidx.core.content.ContextCompat;

import android.Manifest;
import android.app.Activity;
import android.content.Context;
import android.content.pm.ActivityInfo;
import android.content.pm.PackageManager;
import android.graphics.Bitmap;
import android.os.Bundle;
import android.provider.ContactsContract;
import android.util.Log;
import android.view.View;
import android.view.WindowManager;
import android.widget.Button;
import android.widget.Toast;

import org.opencv.android.BaseLoaderCallback;
import org.opencv.android.CameraActivity;
import org.opencv.android.CameraBridgeViewBase;
import org.opencv.android.CameraBridgeViewBase.CvCameraViewListener2;
import org.opencv.android.JavaCameraView;
import org.opencv.android.LoaderCallbackInterface;
import org.opencv.android.OpenCVLoader;
import org.opencv.android.Utils;
import org.opencv.core.Core;
import org.opencv.core.CvType;
import org.opencv.core.Mat;
import org.opencv.core.MatOfRect;
import org.opencv.core.Point;
import org.opencv.core.Rect;
import org.opencv.core.Scalar;
import org.opencv.core.Size;
import org.opencv.imgproc.Imgproc;
import org.opencv.objdetect.CascadeClassifier;

import java.io.File;
import java.io.FileOutputStream;
import java.io.InputStream;
import java.util.ArrayList;
import java.util.List;

public class MainActivity extends CameraActivity implements View.OnClickListener, CvCameraViewListener2 {
//public class MainActivity extends CameraActivity implements View.OnClickListener {
private static final String TAG = “…OpencvCam…”;
private JavaCameraView cameraView;
private Button switchButton;
private boolean isFrontCamera = true;
private Mat mRgba,leftEye_template,rightEye_template;
private CascadeClassifier classifier, classifierEye;
private static final Scalar EYE_RECT_COLOR = new Scalar(0,0,255);
private int mAbsoluteFaceSize = 0;
// private CameraBridgeViewBase.CvCameraViewListener2 cvCameraViewListener2 = new CameraBridgeViewBase.CvCameraViewListener2() {
// @Override
// public void onCameraViewStarted(int width, int height) {
// Log.i(TAG, “onCameraViewStarted width=” + width + “, height=” + height);
// }
//
// @Override
// public void onCameraViewStopped() {
// Log.i(TAG, “onCameraViewStopped”);
// }
//
// @Override
// public Mat onCameraFrame(CameraBridgeViewBase.CvCameraViewFrame inputFrame) {
// System.out.println(“…onCameraFrame…”);
// return inputFrame.rgba();
// }
// };

// private BaseLoaderCallback baseLoaderCallback = new BaseLoaderCallback(this) {
// @Override
// public void onManagerConnected(int status) {
// Log.i(TAG, “onManagerConnected status=” + status + “, javaCameraView=” + cameraView);
// switch (status) {
// case LoaderCallbackInterface.SUCCESS: {
// if (cameraView != null) {
// cameraView.setCvCameraViewListener(MainActivity.this);
// // 禁用帧率显示
// cameraView.disableFpsMeter();
// cameraView.enableView();
// }
// }
// break;
// default:
// super.onManagerConnected(status);
// break;
// }
// }
// };

//复写父类的 getCameraViewList 方法，把 javaCameraView 送到父 Activity，一旦权限被授予之后，javaCameraView 的 setCameraPermissionGranted 就会自动被调用。
@Override
protected List<? extends CameraBridgeViewBase> getCameraViewList() {Log.i(TAG, "getCameraViewList");List<CameraBridgeViewBase> list = new ArrayList<>();list.add(cameraView);return list;
}@Override
protected void onCreate(Bundle savedInstanceState) {super.onCreate(savedInstanceState);initWindowSettings();setContentView(R.layout.activity_main);initLoadOpenCV();cameraView = (JavaCameraView) findViewById(R.id.camera_view);cameraView.setCvCameraViewListener(this);System.out.println(".........cameraView.setCvCameraViewListener..........");switchButton = (Button) findViewById(R.id.switchCamera);switchButton.setOnClickListener(this);

// if (ContextCompat.checkSelfPermission(this, Manifest.permission.CAMERA)!= PackageManager.PERMISSION_DENIED) {
// ActivityCompat.requestPermissions(this, new String[]{Manifest.permission.CAMERA},1);
// } else {
// cameraView.setCameraPermissionGranted();
// }
boolean havePermission = getPermissionCamera(this);
System.out.println(“…getPermissionCamera…”+havePermission);
initClassifier();
initEyeDetector();
leftEye_template = new Mat();
rightEye_template = new Mat();

    cameraView.setCameraIndex(CameraBridgeViewBase.CAMERA_ID_BACK);isFrontCamera=false;cameraView.enableView();
}/*** 确认camera权限* @param activity* @return*/
public static boolean getPermissionCamera(Activity activity) {int cameraPermissionCheck = ContextCompat.checkSelfPermission(activity, Manifest.permission.CAMERA);int readPermissionCheck = ContextCompat.checkSelfPermission(activity, Manifest.permission.READ_EXTERNAL_STORAGE);int writePermissionCheck = ContextCompat.checkSelfPermission(activity, Manifest.permission.WRITE_EXTERNAL_STORAGE);if (cameraPermissionCheck != PackageManager.PERMISSION_GRANTED|| readPermissionCheck != PackageManager.PERMISSION_GRANTED|| writePermissionCheck != PackageManager.PERMISSION_GRANTED) {String[] permissions = new String[]{Manifest.permission.CAMERA,Manifest.permission.READ_EXTERNAL_STORAGE,Manifest.permission.WRITE_EXTERNAL_STORAGE};ActivityCompat.requestPermissions(activity,permissions,0);return false;} else {return true;}
}
private void initWindowSettings() {getWindow().setFlags(WindowManager.LayoutParams.FLAG_FULLSCREEN,WindowManager.LayoutParams.FLAG_FULLSCREEN);getWindow().addFlags(WindowManager.LayoutParams.FLAG_KEEP_SCREEN_ON);setRequestedOrientation(ActivityInfo.SCREEN_ORIENTATION_LANDSCAPE);
}private void initLoadOpenCV() {boolean success = OpenCVLoader.initDebug();if(success) {Toast.makeText(this, "Loading opencv ......", Toast.LENGTH_SHORT).show();} else {Toast.makeText(this, "Can't load opencv", Toast.LENGTH_SHORT).show();}
}@Override
public void onCameraViewStarted(int width, int height) {System.out.println(".........onCameraViewStarted..........");Toast.makeText(this, "onCameraViewStarted ", Toast.LENGTH_SHORT).show();mRgba = new Mat();
}@Override
public void onCameraViewStopped() {mRgba.release();
}@Override
public Mat onCameraFrame(CameraBridgeViewBase.CvCameraViewFrame inputFrame) {

// System.out.println(“…onCameraFrame…”);
mRgba = inputFrame.rgba();

    if(isFrontCamera) {//Core.rotate(mRgba,mRgba,Core.ROTATE_180);Core.flip(mRgba,mRgba,1);//解决前置镜头上下颠倒}return myfacedetect1(mRgba);
}//初始化人脸级联分类器
private void initClassifier() {try {InputStream is = getResources().openRawResource(R.raw.lbpcascade_frontalface_improved);File cascadeDir = getDir("cascade", Context.MODE_PRIVATE);File cascadeFile = new File(cascadeDir, "lbpcascade_frontalface_improved.xml");FileOutputStream os = new FileOutputStream(cascadeFile);byte[] buffer = new byte[4096];int bytesRead;while ((bytesRead = is.read(buffer)) != -1) {os.write(buffer, 0, bytesRead);}is.close();os.close();classifier = new CascadeClassifier(cascadeFile.getAbsolutePath());cascadeFile.delete();cascadeDir.delete();}   catch (Exception e) {e.printStackTrace();}
}private Mat myfacedetect(Mat srcmat) {Imgproc.cvtColor(srcmat,srcmat,Imgproc.COLOR_BGRA2GRAY);MatOfRect faces = new MatOfRect();classifier.detectMultiScale(srcmat,faces,1.1,1,0,new Size(30,30), new Size());List<Rect> faceList = faces.toList();

// srcmat.copyTo(dstmat3);
if(faceList.size()>0) {
// Toast.makeText(MainActivity.this, “Michael test”, Toast.LENGTH_SHORT).show();
for(Rect rect : faceList) {
Imgproc.rectangle(srcmat,rect.tl(),rect.br(),new Scalar(255,0,255),4,8,0);
}
}
return srcmat;
}

private Mat myfacedetect1(Mat mRgba) {float mRelativefaceSize = 0.2f;if (mAbsoluteFaceSize == 0) {int height = mRgba.rows();if (Math.round(height * mRelativefaceSize) > 0) {mAbsoluteFaceSize = Math.round(height*mRelativefaceSize);}}MatOfRect faces = new MatOfRect();if(classifier != null) {classifier.detectMultiScale(mRgba,faces,1.1,2,2,new Size(mAbsoluteFaceSize,mAbsoluteFaceSize), new Size());}Rect[] facesArray = faces.toArray();Scalar faceRectColor = new Scalar(0,255,0,255);for (int i = 0; i<facesArray.length;i++) {Imgproc.rectangle(mRgba,facesArray[i].tl(),facesArray[i].br(),faceRectColor,2);selectEyesArea(facesArray[i],mRgba);}return mRgba;
}//选定眼睛区域
private void selectEyesArea(Rect faceROI, Mat frame) {int offy = (int) (faceROI.height * 0.15f);int offx = (int) (faceROI.width * 0.12f);int sh = (int) (faceROI.height * 0.35f);int sw = (int) (faceROI.width * 0.3f);int gap = (int) (faceROI.width * 0.25f);Point lp_eye = new Point(faceROI.tl().x+offx,faceROI.tl().y+offy);Point lp_end = new Point(lp_eye.x+sw,lp_eye.y+sh);Imgproc.rectangle(frame,lp_eye,lp_end,EYE_RECT_COLOR,2);int right_offx = (int) (faceROI.width * 0.08f);Point rp_eye = new Point(faceROI.x+faceROI.width/2+right_offx,faceROI.tl().y+offy);Point rp_end = new Point(rp_eye.x+sw,rp_eye.y+sh);Imgproc.rectangle(frame,rp_eye,rp_end,EYE_RECT_COLOR,2);//使用级联分类器检测眼睛MatOfRect eyes = new MatOfRect();Rect left_eye_roi = new Rect();left_eye_roi.x = (int) lp_eye.x;left_eye_roi.y = (int) lp_eye.y;left_eye_roi.width = (int) (lp_end.x - lp_eye.x);left_eye_roi.height = (int) (lp_end.y - lp_eye.y);Rect right_eye_roi = new Rect();right_eye_roi.x = (int) rp_eye.x;right_eye_roi.y = (int) rp_eye.y;right_eye_roi.width = (int) (rp_end.x - rp_eye.x);right_eye_roi.height = (int) (rp_end.y - rp_eye.y);//级联分类器Mat leftEye = frame.submat(left_eye_roi);Mat rightEye = frame.submat(right_eye_roi);classifierEye.detectMultiScale(mRgba.submat(left_eye_roi),eyes,1.15,2,0,new Size(30,30),new Size());Rect[] eyesArray = eyes.toArray();for(int i=0; i<eyesArray.length;i++){Log.i(TAG, "Found left Eyes... ");leftEye.submat(eyesArray[i]).copyTo(leftEye_template);}if(eyesArray.length==0){Rect left_roi = matchEyeTemplate(leftEye,true);if(left_roi != null) {Imgproc.rectangle(leftEye,left_roi.tl(),left_roi.br(),EYE_RECT_COLOR,2);}}eyes.release();eyes = new MatOfRect();classifierEye.detectMultiScale(mRgba.submat(right_eye_roi),eyes,1.15,2,0,new Size(30,30),new Size());eyesArray = eyes.toArray();for(int i=0; i<eyesArray.length;i++){Log.i(TAG, "Found right Eyes... ");rightEye.submat(eyesArray[i]).copyTo(rightEye_template);}if(eyesArray.length==0){Rect right_roi = matchEyeTemplate(rightEye,true);if(right_roi != null) {Imgproc.rectangle(rightEye,right_roi.tl(),right_roi.br(),EYE_RECT_COLOR,2);}}
}private Rect matchEyeTemplate(Mat src, Boolean left){Mat tpl = left ? leftEye_template : rightEye_template;if(tpl.cols() ==0 || tpl.rows() == 0) {return null;}int height = src.rows() - tpl.rows()+1;int width = src.cols() - tpl.cols()+1;if(height<1 || width <1){return null;}Mat result = new Mat(height,width, CvType.CV_32FC1);//模板匹配int method = Imgproc.TM_CCOEFF_NORMED;Imgproc.matchTemplate(src, tpl, result,method);Core.MinMaxLocResult minMaxLocResult = Core.minMaxLoc(result);Point maxloc = minMaxLocResult.maxLoc;//ROIRect rect = new Rect();rect.x = (int) (maxloc.x);rect.y = (int) (maxloc.y);rect.width = tpl.cols();rect.height = tpl.rows();result.release();return rect;
}private void initEyeDetector() {try {InputStream is = getResources().openRawResource(R.raw.haarcascade_eye_tree_eyeglasses);File cascadeDir = getDir("cascade", Context.MODE_PRIVATE);File cascadeFile = new File(cascadeDir, "haarcascade_eye_tree_eyeglasses.xml");FileOutputStream os = new FileOutputStream(cascadeFile);byte[] buffer = new byte[4096];int bytesRead;while ((bytesRead = is.read(buffer)) != -1) {os.write(buffer, 0, bytesRead);}is.close();os.close();classifierEye = new CascadeClassifier(cascadeFile.getAbsolutePath());cascadeFile.delete();cascadeDir.delete();}   catch (Exception e) {e.printStackTrace();}
}@Override
public void onClick(View view) {switch (view.getId()){case R.id.switchCamera:if(isFrontCamera) {cameraView.setCameraIndex(CameraBridgeViewBase.CAMERA_ID_BACK);isFrontCamera=false;System.out.println("isFrontCamera=false");} else {cameraView.setCameraIndex(CameraBridgeViewBase.CAMERA_ID_FRONT);isFrontCamera=true;System.out.println("isFrontCamera=true");}}if(cameraView != null) {cameraView.disableView();}cameraView.enableView();System.out.println("..........onClick enableView............");

// Toast.makeText(this, "…enableView… ", Toast.LENGTH_SHORT).show();
}

@Override
protected void onDestroy() {super.onDestroy();if(cameraView != null) {cameraView.disableView();}
}

}

结果：

在这里插入图片描述