高强度学习训练第二天总结：Opencv+Android+CameraView小demo

前言：网上已经有很多人将Opencv集成进Android项目中了。因此我只给大家看Gradle文件和项目目录。

1、gradle

三个gradle script

// Top-level build file where you can add configuration options common to all sub-projects/modules.

buildscript {
    repositories {
        google()
        jcenter()
        
    }
    dependencies {
        classpath 'com.android.tools.build:gradle:3.5.0'
        
        // NOTE: Do not place your application dependencies here; they belong
        // in the individual module build.gradle files
    }
}

allprojects {
    repositories {
        google()
        jcenter()
        
    }
}

task clean(type: Delete) {
    delete rootProject.buildDir
}

apply plugin: 'com.android.application'

android {
    compileSdkVersion 28
    defaultConfig {
        applicationId "cn.baldorange.myapplication"
        minSdkVersion 22
        targetSdkVersion 28
        versionCode 1
        versionName "1.0"
        testInstrumentationRunner "androidx.test.runner.AndroidJUnitRunner"
    }
    buildTypes {
        release {
            minifyEnabled false
            proguardFiles getDefaultProguardFile('proguard-android-optimize.txt'), 'proguard-rules.pro'
        }
    }
}

dependencies {
    implementation fileTree(dir: 'libs', include: ['*.jar'])
    implementation 'androidx.appcompat:appcompat:1.0.2'
    implementation 'androidx.constraintlayout:constraintlayout:1.1.3'
    testImplementation 'junit:junit:4.12'
    androidTestImplementation 'androidx.test:runner:1.1.1'
    androidTestImplementation 'androidx.test.espresso:espresso-core:3.1.1'
    implementation project(':openCVLibrary347')
    implementation fileTree(dir: "$buildDir/native-libs", include: 'native-libs.jar')
}
task nativeLibsToJar(type: Jar, description: 'create a jar archive of the native libs') {
    destinationDir file("$buildDir/native-libs")
    baseName 'native-libs'
    from fileTree(dir: 'libs', include: '**/*.so')
    into 'lib/'
}
tasks.withType(JavaCompile) {
    compileTask -> compileTask.dependsOn(nativeLibsToJar)
}

apply plugin: 'com.android.library'

android {
    compileSdkVersion 28
    buildToolsVersion "28.0.3"

    defaultConfig {
        minSdkVersion 22
        targetSdkVersion 28
    }

    buildTypes {
        release {
            minifyEnabled false
            proguardFiles getDefaultProguardFile('proguard-android.txt'), 'proguard-rules.txt'
        }
    }
}

二、JNILIB

 三、MainActivity

package cn.baldorange.myapplication;

import androidx.appcompat.app.AppCompatActivity;
import cn.baldorange.myapplication.activities.CameraActivity;

import android.content.Intent;
import android.graphics.Bitmap;
import android.graphics.BitmapFactory;
import android.os.Bundle;
import android.view.View;
import android.widget.Button;
import android.widget.ImageView;
import android.widget.Toast;

import org.opencv.android.OpenCVLoader;
import org.opencv.android.Utils;
import org.opencv.core.Mat;
import org.opencv.imgproc.Imgproc;

public class MainActivity extends AppCompatActivity {

    private ImageView imageView;
    private Button button;
    private Button button2;
    @Override
    protected void onCreate(Bundle savedInstanceState) {
        super.onCreate(savedInstanceState);
        setContentView(R.layout.activity_main);
        initView();
        //初始化
        if (OpenCVLoader.initDebug()) {
            Toast.makeText(this, "OpenCVLoader初始化成功", Toast.LENGTH_SHORT).show();
        }

        //测试灰度
        button.setOnClickListener(new View.OnClickListener() {
            @Override
            public void onClick(View v) {
                convert2Grey();
            }
        });

        button2.setOnClickListener(new View.OnClickListener() {
            @Override
            public void onClick(View v) {
                Intent i = new Intent(MainActivity.this, CameraActivity.class);
                startActivity(i);
            }
        });
    }

    private void convert2Grey() {
        Mat src = new Mat();//Mat是OpenCV的一种图像格式
        Mat temp = new Mat();
        Mat dst = new Mat();
        Bitmap bitmap = BitmapFactory.decodeResource(this.getResources(), R.drawable.powershell);
        Utils.bitmapToMat(bitmap, src);
        Imgproc.cvtColor(src, temp, Imgproc.COLOR_RGB2BGR);
        Imgproc.cvtColor(temp, dst, Imgproc.COLOR_BGR2GRAY);
        Utils.matToBitmap(dst, bitmap);
        imageView.setImageBitmap(bitmap);
        //
        src.release();
        temp.release();
        dst.release();
    }

    private void initView() {
        imageView = (ImageView) findViewById(R.id.imageView);
        button = (Button) findViewById(R.id.button);
        button2 = findViewById(R.id.button2);
    }
}

package cn.baldorange.myapplication.activities;

import androidx.appcompat.app.AppCompatActivity;
import cn.baldorange.myapplication.MainActivity;
import cn.baldorange.myapplication.R;

import android.content.pm.ActivityInfo;
import android.os.Bundle;
import android.os.Environment;
import android.os.Handler;
import android.os.Message;
import android.util.Log;
import android.view.View;
import android.widget.Button;
import android.widget.Toast;

import org.opencv.android.BaseLoaderCallback;
import org.opencv.android.CameraBridgeViewBase;
import org.opencv.android.LoaderCallbackInterface;
import org.opencv.android.OpenCVLoader;
import org.opencv.core.CvType;
import org.opencv.core.Mat;
import org.opencv.imgcodecs.Imgcodecs;
import org.opencv.imgproc.Imgproc;

import java.io.File;
import java.util.Date;

public class CameraActivity extends AppCompatActivity implements CameraBridgeViewBase.CvCameraViewListener2{

    private String TAG = "OpenCV_Test";
    //OpenCV的相机接口
    private CameraBridgeViewBase mCVCamera;
    //缓存相机每帧输入的数据
    private Mat mRgba;
    private Button button;

    /**通过OpenCV管理Android服务，初始化OpenCV**/
    BaseLoaderCallback mLoaderCallback = new BaseLoaderCallback(this) {
        @Override
        public void onManagerConnected(int status) {
            switch (status) {
                case LoaderCallbackInterface.SUCCESS:
                    Log.i(TAG, "OpenCV loaded successfully");
                    mCVCamera.enableView();
                    break;
                default:break;
            }
        }
    };
    Handler handler = new Handler(){
        @Override
        public void handleMessage(Message msg){
            super.handleMessage(msg);
            if(msg.what == 1){
                button.performClick();
            }
        }
    };
    @Override
    protected void onCreate(Bundle savedInstanceState) {

        super.onCreate(savedInstanceState);
        setContentView(R.layout.activity_camera);
        //初始化并设置预览部件
        mCVCamera = (CameraBridgeViewBase) findViewById(R.id.camera_view);
        mCVCamera.setCvCameraViewListener(this);

        //拍照按键
        button = (Button) findViewById(R.id.deal_btn);

        button.setOnClickListener(new View.OnClickListener() {
            @Override
            public void onClick(View v) {
                if(mRgba != null) {
                    if(!mRgba.empty()) {
                        Mat inter = new Mat(mRgba.width(), mRgba.height(), CvType.CV_8UC4);
                        Log.e("Mat","...............1...............");
                        //将四通道的RGBA转为三通道的BGR，重要！！
                        Imgproc.cvtColor(mRgba, inter, Imgproc.COLOR_RGBA2BGR);
                        Log.e("Mat","...............2...............");
                        File sdDir = null;
                        //判断是否存在机身内存
                        boolean sdCardExist = Environment.getExternalStorageState().equals(Environment.MEDIA_MOUNTED);
                        if(sdCardExist) {
                            //获得机身储存根目录
                            sdDir = Environment.getExternalStorageDirectory();
                            Log.e("Mat","...............3...............");
                        }
                        //将拍摄准确时间作为文件名
                        java.text.SimpleDateFormat sdf = new java.text.SimpleDateFormat("yyyy-MM-dd_HH-mm-ss");
                        String filename = sdf.format(new Date());
                        String savepath=sdDir + "/Pictures/OpenCV/";
                        File f=new File(savepath);
                        if(!f.exists()){
                            f.mkdirs();
                        }
                        String filePath = sdDir + "/Pictures/OpenCV/" + filename + ".png";
                        Log.e("Mat","..............."+filePath+"...............");
                        //将转化后的BGR矩阵内容写入到文件中
                        Imgcodecs.imwrite(filePath, inter);
                        Toast.makeText(CameraActivity.this, "图片保存到: "+ filePath, Toast.LENGTH_SHORT).show();
                    }
                }
            }
        });

        // moveTaskToBack(true);
//        new test().start();
    }
    private class test extends Thread{
        @Override
        public void run() {
            super.run();
            while (true){
                try {
                    Thread.sleep(2000);
                    Log.e("begin","kaishi.........");

                    Message message = new Message();
                    message.what = 1;
                    handler.sendMessage(message);
                }catch (Exception e){
                    Log.e("error",e.getMessage());
                }
            }
        }
    }
    @Override
    protected void onResume() {
        /***强制横屏***/
        if (getRequestedOrientation() != ActivityInfo.SCREEN_ORIENTATION_LANDSCAPE) {
            setRequestedOrientation(ActivityInfo.SCREEN_ORIENTATION_LANDSCAPE);
        } else {
            //横屏后才加载部件，否则会FC
            if(!OpenCVLoader.initDebug()) {
                Log.d(TAG, "OpenCV library not found!");
            } else {
                Log.d(TAG, "OpenCV library found inside package. Using it!");
                mLoaderCallback.onManagerConnected(LoaderCallbackInterface.SUCCESS);
            }
        }
        super.onResume();
    }

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

    //对象实例化及基本属性的设置，包括长度、宽度和图像类型标志
    public void onCameraViewStarted(int width, int height) {
        Log.e("Mat","...............4...............");
        mRgba = new Mat(height, width, CvType.CV_8UC4);
    }

    /**图像处理都写在这里！！！**/
    @Override
    public Mat onCameraFrame(CameraBridgeViewBase.CvCameraViewFrame inputFrame) {
        mRgba = inputFrame.rgba();  //一定要有！！！不然数据保存不进MAT中！！！
        //直接返回输入视频预览图的RGB数据并存放在Mat数据中
        Log.e("Mat","...............5...............");
        return mRgba;
    }

    //结束时释放
    @Override
    public void onCameraViewStopped() {
        Log.e("Mat","...............6...............");
        mRgba.release();
        // mTmp.release();
    }
}

四、运行结果