OpenCV-Android-카메라 띄우기

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https://webnautes.tistory.com/1054?category=704164 

Android NDK + CMake + OpenCV 카메라 예제 및 프로젝트 생성방법(Android Camera Example with NDK, OpenCV, CMake )

https://www.youtube.com/watch?v=oFFnyJAIJp8&list=PLwfJJiO20qkB7EhtRITL3znme8mIgOwID&ab_channel=%EB%A9%88%EC%B6%A4%EB%B3%B4%EB%8B%A8%EC%B2%9C%EC%B2%9C%ED%9E%88%EB%9D%BC%EB%8F%84 

 

다시 정리를 해보면

- 프로젝트 시작

- SDK Manager : Configure -> SDK Manager

  (안드로이드 스튜디오 상에서는 Tools -> SDK Manager 로 들어가면 됨)

- Android 11 설치 ( SDK Platforms)

 

- SDK Tools ( Show Package Details 체크박스)

- SDK Tools ( Android SDK / NDK / CMake )

- opencv sdk 다운로드

 

- opencv-4.5.2-android-sdk.zip

- 다운로드한 파일을 C:\ 로 복사하고 압축해제

- 압축푼 폴더 경로 확인하기 

- 새 프로젝트 시작 -> Native C++

- Import Module ( File -> New -> Import Module... )

- C:\OpenCV-android-sdk\sdk 폴더 Import

- 추가된 폴더

- Project Structure...

- res -> values -> themes -> themes.xml 수정

        <!-- No Title Bar-->
        <item name="windowActionBar">false</item>
        <item name="windowNoTitle">true</item>

- res -> layout -> activity_main.xml 수정 ( 기존내용을 삭제하고 아래 코드를 붙여넣기 )

<?xml version="1.0" encoding="utf-8"?>
<LinearLayout
    xmlns:android="http://schemas.android.com/apk/res/android"
    xmlns:opencv="http://schemas.android.com/apk/res-auto"
    xmlns:tools="http://schemas.android.com/tools"
    android:layout_width="match_parent"
    android:layout_height="match_parent"
    android:orientation="vertical"
    tools:context=".MainActivity">

    <org.opencv.android.JavaCameraView
        android:layout_width="match_parent"
        android:layout_height="match_parent"
        opencv:camera_id="any"
        android:visibility="gone"
        android:id="@+id/activity_surface_view" />

</LinearLayout>

- AndroidManifest.xml

- AndroidManifast.xml 수정 2 : 화면 가로로 바꾸기

        <activity android:name=".MainActivity"
            android:screenOrientation="landscape"
            android:configChanges="keyboardHidden|orientation">

- MainActivity.java (첫 줄을 제외하고 모두 삭제후 붙여넣기 )

import androidx.appcompat.app.AlertDialog;
import androidx.appcompat.app.AppCompatActivity;

import android.content.DialogInterface;
import android.os.Bundle;
import android.annotation.TargetApi;
import android.content.pm.PackageManager;
import android.os.Build;
import android.util.Log;
import android.view.SurfaceView;
import android.view.WindowManager;
import org.opencv.android.BaseLoaderCallback;
import org.opencv.android.CameraBridgeViewBase;
import org.opencv.android.LoaderCallbackInterface;
import org.opencv.android.OpenCVLoader;
import org.opencv.core.Mat;

import java.util.Collections;
import java.util.List;

import static android.Manifest.permission.CAMERA;


public class MainActivity extends AppCompatActivity
        implements CameraBridgeViewBase.CvCameraViewListener2 {

    private static final String TAG = "opencv";
    private Mat matInput;
    private Mat matResult;

    private CameraBridgeViewBase mOpenCvCameraView;

    public native void ConvertRGBtoGray(long matAddrInput, long matAddrResult);


    static {
        System.loadLibrary("opencv_java4");
        System.loadLibrary("native-lib");
    }



    private BaseLoaderCallback mLoaderCallback = new BaseLoaderCallback(this) {
        @Override
        public void onManagerConnected(int status) {
            switch (status) {
                case LoaderCallbackInterface.SUCCESS:
                {
                    mOpenCvCameraView.enableView();
                } break;
                default:
                {
                    super.onManagerConnected(status);
                } break;
            }
        }
    };


    @Override
    protected void onCreate(Bundle savedInstanceState) {
        super.onCreate(savedInstanceState);

        getWindow().setFlags(WindowManager.LayoutParams.FLAG_FULLSCREEN,
                WindowManager.LayoutParams.FLAG_FULLSCREEN);
        getWindow().setFlags(WindowManager.LayoutParams.FLAG_KEEP_SCREEN_ON,
                WindowManager.LayoutParams.FLAG_KEEP_SCREEN_ON);

        setContentView(R.layout.activity_main);

        mOpenCvCameraView = (CameraBridgeViewBase)findViewById(R.id.activity_surface_view);
        mOpenCvCameraView.setVisibility(SurfaceView.VISIBLE);
        mOpenCvCameraView.setCvCameraViewListener(this);
        mOpenCvCameraView.setCameraIndex(0); // front-camera(1),  back-camera(0)
    }

    @Override
    public void onPause()
    {
        super.onPause();
        if (mOpenCvCameraView != null)
            mOpenCvCameraView.disableView();
    }

    @Override
    public void onResume()
    {
        super.onResume();

        if (!OpenCVLoader.initDebug()) {
            Log.d(TAG, "onResume :: Internal OpenCV library not found.");
            OpenCVLoader.initAsync(OpenCVLoader.OPENCV_VERSION_3_2_0, this, mLoaderCallback);
        } else {
            Log.d(TAG, "onResum :: OpenCV library found inside package. Using it!");
            mLoaderCallback.onManagerConnected(LoaderCallbackInterface.SUCCESS);
        }
    }


    public void onDestroy() {
        super.onDestroy();

        if (mOpenCvCameraView != null)
            mOpenCvCameraView.disableView();
    }

    @Override
    public void onCameraViewStarted(int width, int height) {

    }

    @Override
    public void onCameraViewStopped() {

    }

    @Override
    public Mat onCameraFrame(CameraBridgeViewBase.CvCameraViewFrame inputFrame) {

        matInput = inputFrame.rgba();

        if ( matResult == null )

            matResult = new Mat(matInput.rows(), matInput.cols(), matInput.type());

        ConvertRGBtoGray(matInput.getNativeObjAddr(), matResult.getNativeObjAddr());

        return matResult;
    }


    protected List<? extends CameraBridgeViewBase> getCameraViewList() {
        return Collections.singletonList(mOpenCvCameraView);
    }


    //여기서부턴 퍼미션 관련 메소드
    private static final int CAMERA_PERMISSION_REQUEST_CODE = 200;


    protected void onCameraPermissionGranted() {
        List<? extends CameraBridgeViewBase> cameraViews = getCameraViewList();
        if (cameraViews == null) {
            return;
        }
        for (CameraBridgeViewBase cameraBridgeViewBase: cameraViews) {
            if (cameraBridgeViewBase != null) {
                cameraBridgeViewBase.setCameraPermissionGranted();
            }
        }
    }

    @Override
    protected void onStart() {
        super.onStart();
        boolean havePermission = true;
        if (Build.VERSION.SDK_INT >= Build.VERSION_CODES.M) {
            if (checkSelfPermission(CAMERA) != PackageManager.PERMISSION_GRANTED) {
                requestPermissions(new String[]{CAMERA}, CAMERA_PERMISSION_REQUEST_CODE);
                havePermission = false;
            }
        }
        if (havePermission) {
            onCameraPermissionGranted();
        }
    }

    @Override
    @TargetApi(Build.VERSION_CODES.M)
    public void onRequestPermissionsResult(int requestCode, String[] permissions, int[] grantResults) {
        if (requestCode == CAMERA_PERMISSION_REQUEST_CODE && grantResults.length > 0
                && grantResults[0] == PackageManager.PERMISSION_GRANTED) {
            onCameraPermissionGranted();
        }else{
            showDialogForPermission("앱을 실행하려면 퍼미션을 허가하셔야합니다.");
        }
        super.onRequestPermissionsResult(requestCode, permissions, grantResults);
    }


    @TargetApi(Build.VERSION_CODES.M)
    private void showDialogForPermission(String msg) {

        AlertDialog.Builder builder = new AlertDialog.Builder( MainActivity.this);
        builder.setTitle("알림");
        builder.setMessage(msg);
        builder.setCancelable(false);
        builder.setPositiveButton("예", new DialogInterface.OnClickListener() {
            public void onClick(DialogInterface dialog, int id){
                requestPermissions(new String[]{CAMERA}, CAMERA_PERMISSION_REQUEST_CODE);
            }
        });
        builder.setNegativeButton("아니오", new DialogInterface.OnClickListener() {
            public void onClick(DialogInterface arg0, int arg1) {
                finish();
            }
        });
        builder.create().show();
    }


}

- ConvertRGBtoGray( ) 수정

 

- native-lib.cpp 내용 삭제

- 빨간 사각형 부분 추가

  : 빨간 줄 및 에러는 다음 단계에서 해결됨

#include <jni.h>
#include <opencv2/opencv.hpp>
using namespace cv;

extern "C"
JNIEXPORT void JNICALL
Java_com_example_myopencvapp_MainActivity_ConvertRGBtoGray(JNIEnv *env, jobject thiz,
                                                           jlong mat_addr_input,
                                                           jlong mat_addr_result) {
    // TODO: implement ConvertRGBtoGray()
    Mat &matInput = *(Mat *)mat_addr_input;
    Mat &matResult = *(Mat *)mat_addr_result;

    cvtColor(matInput, matResult, COLOR_RGBA2GRAY);
}

- CMakeLists.txt 수정

 현재 프로젝트가 생성된 위치를 찾아 경로 확인해서 붙여 넣으면 됨 ( \ -> / 로 바꾸면 됨)

 프로젝트 경로 C:\Users\w\AndroidStudioProjects\MyOpenCvApp 

 -> C:/Users/w/AndroidStudioProjects/MyOpenCvApp

# For more information about using CMake with Android Studio, read the
# documentation: https://d.android.com/studio/projects/add-native-code.html

# Sets the minimum version of CMake required to build the native library.

cmake_minimum_required(VERSION 3.4.1)

set(pathPROJECT C:/Users/w/AndroidStudioProjects/MyOpenCvApp) # 수정필요
set(pathOPENCV ${pathPROJECT}/sdk) # 수정 필요
set(pathLIBOPENCV_JAVA ${pathOPENCV}/native/libs/${ANDROID_ABI}/libopencv_java4.so)

set(CMAKE_VERBOSE_MAKEFILE on)
set(CMAKE_CXX_FLAGS "${CMAKE_CXX_FLAGS} -std=gnu++11")

include_directories(${pathOPENCV}/native/jni/include)


# Creates and names a library, sets it as either STATIC
# or SHARED, and provides the relative paths to its source code.
# You can define multiple libraries, and CMake builds them for you.
# Gradle automatically packages shared libraries with your APK.

add_library( # Sets the name of the library.
        native-lib

        # Sets the library as a shared library.
        SHARED

        # Provides a relative path to your source file(s).
        ${pathPROJECT}/app/src/main/cpp/native-lib.cpp )



add_library( lib_opencv SHARED IMPORTED )

set_target_properties(lib_opencv PROPERTIES IMPORTED_LOCATION ${pathLIBOPENCV_JAVA})


# Searches for a specified prebuilt library and stores the path as a
# variable. Because CMake includes system libraries in the search path by
# default, you only need to specify the name of the public NDK library
# you want to add. CMake verifies that the library exists before
# completing its build.

find_library( # Sets the name of the path variable.
        log-lib

        # Specifies the name of the NDK library that
        # you want CMake to locate.
        log )

# Specifies libraries CMake should link to your target library. You
# can link multiple libraries, such as libraries you define in this
# build script, prebuilt third-party libraries, or system libraries.

target_link_libraries( # Specifies the target library.
        native-lib

        lib_opencv

        # Links the target library to the log library
        # included in the NDK.
        ${log-lib} )

- 장치에 연결 동작

하고 Run 하면 됨