OpenCV -如何在Android中设置全屏摄像头视图？

jrcvhitl  于 2022-11-24  发布在  Android
关注(0)|答案(2)|浏览(230)

背景

作为一个软件新手，我目前的目标是将我的相机预览格式设置为全屏，这将与Snapchat上的相机预览相同。现在，我能够以1：1的框格式展示我的相机预览，我能够通过以下this tutorial设置。我在其他问题中遇到的其他潜在解决方案要么拉伸/扭曲预览图像，要么根本没有启动应用程序。我如何能够在保持肖像模式的同时做到这一点？下面提供的代码
其他设备规格包括，我的目标是启动应用程序的设备是一个OnePlus六，其纵横比是19：9。这是我的应用程序上的相机目前看起来像这样。
x1c 0d1x。
我想消除预览上方和下方的黑色边框，让相机占据整个屏幕。

主要活动.java

package com.example.cv;

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

import android.Manifest;
import android.content.pm.PackageManager;
import android.opengl.Matrix;
import android.os.Bundle;
import android.util.Log;
import android.view.SurfaceView;
import android.view.WindowManager;
import android.widget.Toast;

import org.opencv.android.BaseLoaderCallback;
import org.opencv.android.CameraBridgeViewBase;
import org.opencv.android.JavaCameraView;
import org.opencv.android.OpenCVLoader;
import org.opencv.core.Core;
import org.opencv.core.CvType;
import org.opencv.core.Mat;
import org.opencv.imgproc.Imgproc;

public class MainActivity extends AppCompatActivity implements CameraBridgeViewBase.CvCameraViewListener2
{
    private static String TAG = "MainActivity";
    JavaCameraView javaCameraView;
    Mat mRGBA, mRGBAT, dst;

    private static final int MY_CAMERA_REQUEST_CODE = 100;

    BaseLoaderCallback baseLoaderCallback = new BaseLoaderCallback(MainActivity.this) {
        @Override
        public void onManagerConnected(int status)
        {
            if (status == BaseLoaderCallback.SUCCESS) {
                javaCameraView.enableView();
            } else {
                super.onManagerConnected(status);
            }
        }
    };

    static
    {
        if (OpenCVLoader.initDebug())
        {
            Log.d(TAG, "OpenCV is Configured or Connected successfully.");
        }
        else
        {
            Log.d(TAG, "OpenCV not Working or Loaded.");
        }
    }

    @Override
    protected void onCreate(Bundle savedInstanceState)
    {
        super.onCreate(savedInstanceState);
        setContentView(R.layout.activity_main);

        javaCameraView = (JavaCameraView) findViewById(R.id.my_camera_view);


        if (ContextCompat.checkSelfPermission(this, Manifest.permission.CAMERA)
                == PackageManager.PERMISSION_GRANTED)  {
            Log.d(TAG, "Permissions granted");
            javaCameraView.setCameraPermissionGranted();
            javaCameraView.setCameraIndex(CameraBridgeViewBase.CAMERA_ID_BACK);
            javaCameraView.setVisibility(CameraBridgeViewBase.VISIBLE);
            javaCameraView.setCvCameraViewListener(this);
        } else {
            Log.d(TAG, "Permission prompt");
            ActivityCompat.requestPermissions(this, new String[]{Manifest.permission.CAMERA}, MY_CAMERA_REQUEST_CODE);
        }


    }

    @Override
    public void onCameraViewStarted(int width, int height)
    {
        mRGBAT = new Mat();
        dst = new Mat();
    }

    @Override
    public void onCameraViewStopped()
    {
        mRGBA.release();
    }

    @Override
    public Mat onCameraFrame(CameraBridgeViewBase.CvCameraViewFrame inputFrame)
    {
        mRGBA = inputFrame.rgba();
        Core.transpose(mRGBA, mRGBAT);
        Core.flip(mRGBAT, mRGBAT, 1);
        Imgproc.resize(mRGBAT, dst, mRGBA.size());
        mRGBA.release();
        mRGBAT.release();
        return dst;
    }

    @Override
    public void onPointerCaptureChanged(boolean hasCapture) {

    }

    @Override
    protected void onDestroy() {
        super.onDestroy();

        if (javaCameraView != null)
        {
            javaCameraView.disableView();
        }
    }

    @Override
    protected void onPause() {
        super.onPause();

        if (javaCameraView != null)
        {
            javaCameraView.disableView();
        }
    }

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

        if (OpenCVLoader.initDebug())
        {
            Log.d(TAG, "OpenCV is Configured or Connected successfully.");
            baseLoaderCallback.onManagerConnected(BaseLoaderCallback.SUCCESS);
        }
        else
        {
            Log.d(TAG, "OpenCV not Working or Loaded.");
            OpenCVLoader.initAsync(OpenCVLoader.OPENCV_VERSION, this, baseLoaderCallback);
        }
    }

    @Override
    public void onRequestPermissionsResult(int requestCode, @NonNull String[] permissions, @NonNull int[] grantResults) {
        super.onRequestPermissionsResult(requestCode, permissions, grantResults);
        if (requestCode == MY_CAMERA_REQUEST_CODE) {
            // camera can be turned on
            Toast.makeText(this, "camera permission granted", Toast.LENGTH_LONG).show();
            javaCameraView.setCameraPermissionGranted();
            javaCameraView.setCameraIndex(CameraBridgeViewBase.CAMERA_ID_FRONT);
            javaCameraView.setVisibility(CameraBridgeViewBase.VISIBLE);
            javaCameraView.setCvCameraViewListener(this);
        } else {
            //camera will stay off
            Toast.makeText(this, "camera permission denied", Toast.LENGTH_LONG).show();
        }
    }
}

活动主文件.xml

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

    <org.opencv.android.JavaCameraView
        android:id="@+id/my_camera_view"
        android:layout_width="fill_parent"
        android:layout_height="fill_parent"
        />

</RelativeLayout>

安卓清单.xml

<?xml version="1.0" encoding="utf-8"?>
<manifest xmlns:android="http://schemas.android.com/apk/res/android"
    package="com.example.cv">

    <supports-screens android:resizeable="true"
        android:smallScreens="true"
        android:normalScreens="true"
        android:largeScreens="true"
        android:anyDensity="true" />

    <uses-permission android:name="android.permission.CAMERA"/>
    <uses-feature android:name="android.hardware.camera"/>
    <uses-feature android:name="android.hardware.camera.autofocus"/>
    <uses-feature android:name="android.hardware.camera.front"/>
    <uses-feature android:name="android.hardware.camera.front.autofocus"/>

    <application
        android:allowBackup="true"
        android:icon="@mipmap/ic_launcher"
        android:label="@string/app_name"
        android:roundIcon="@mipmap/ic_launcher_round"
        android:supportsRtl="true"
        android:theme="@style/Theme.AppCompat.Light.NoActionBar">
        <activity android:name=".MainActivity"
            android:screenOrientation="portrait"
            android:configChanges="keyboardHidden|orientation">
            <intent-filter>
                <action android:name="android.intent.action.MAIN" />

                <category android:name="android.intent.category.LAUNCHER" />
            </intent-filter>
        </activity>
    </application>

</manifest>

更新：我遇到过一些解决方案，目的是改变方向和/或消除操作栏。应用setMaxFrameSize()除了拉伸CameraPreview的分辨率外不起作用。我看到的另一个答案是getWindow().addFlags(WindowManager.LayoutParams.FLAG_KEEP_SCREEN_ON);，它不再有效，因为FLAG_KEEP_SCREEN_ON已经被弃用。如果有人能提供一点点解决方案，我可以解决这个问题，我会感激不尽的。
更新2：我曾尝试在我的activity_main.xml文件中修改layout_height，结果却让它将预览进一步向下推到屏幕上，同时它仍然保持其1：1框格式。此外，我还考虑在我的MainActivity中实现javaCameraView.getLayoutParams().height=，结果却让它扭曲/拉伸相机预览，而不是实现我的预期愿望。

opencv

2条答案

按热度按时间
wfveoks0

wfveoks01#

简短回答

在代码解释之后，我将在最后给出MainActivity类的完整解决方案-包括后置和前置摄像头

完整详细信息

我在这个网站上加入了一些答案，并修改了onCameraFrame()。现在我可以在人像模式下打开应用程序，作为原生Android相机或Snapchat视图
这个解决方案非常轻量级，我没有像在这个网站上的其他答案中那样更改任何OpenCV文件[例如this one]。根据您要使用的activeCamera [即背面或正面的]，需要在onCameraFrame()内部进行一些修改，我将在下面列出

共同基准

所以我首先按照this answer中的4个步骤进行操作，它们完全按照那里所展示的那样，它们真的让我走上了正确的轨道。值得注意的是，通过这些改变，你会立即获得一个好看的横向视图，但只要你把手机放在纵向位置，上下黑带就会回来。将步骤3中的行更改为：

android:screenOrientation="portrait"

我没有解决。此外，如果你想去全屏你需要删除标题栏，为了做到这一点，我纳入了this answer太多。这意味着你将需要修改这一行也在AndroidManifest.xml从前面的步骤2

android:theme="@style/Theme.AppCompat.Light.NoActionBar.FullScreen"

由于您在两个位置初始化摄像头，并且需要更改它[当前代码片段适用于前置摄像头，您需要后置摄像头]，因此您可以清理代码并开始定义感兴趣的摄像头，以便仅在一个位置修改输入源：

public class MainActivity extends AppCompatActivity implements
        CameraBridgeViewBase.CvCameraViewListener2
{
    ...
    // back camera
    int activeCamera = CameraBridgeViewBase.CAMERA_ID_BACK;
    // front camera
    // int activeCamera = CameraBridgeViewBase.CAMERA_ID_FRONT;

然后将其传递给新的initializeCamera()方法

private void initializeCamera(JavaCameraView javaCameraView, int activeCamera){
    javaCameraView.setCameraPermissionGranted();
    javaCameraView.setCameraIndex(activeCamera);
    javaCameraView.setVisibility(CameraBridgeViewBase.VISIBLE);
    javaCameraView.setCvCameraViewListener(this);
}

只要Android检测到用户已授予CAMERA权限，您就必须调用该函数：

if (ContextCompat.checkSelfPermission(this, Manifest.permission.CAMERA)
            == PackageManager.PERMISSION_GRANTED) {
        Log.d(TAG, "Permissions granted");
        initializeCamera(javaCameraView, activeCamera);

以及：

if (requestCode == MY_CAMERA_REQUEST_CODE) {
        if (grantResults[0] == PackageManager.PERMISSION_GRANTED) {
            Toast.makeText(this, "Camera Permission granted", Toast.LENGTH_LONG).show();
            initializeCamera(javaCameraView, activeCamera);

现在是区分前置和后置摄像头的时候了
"后置摄像头"
在这种情况下，您根本不需要操作帧，代码如下所示：

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

@Override
public Mat onCameraFrame(CameraBridgeViewBase.CvCameraViewFrame inputFrame)
{
    mRGBA = inputFrame.rgba();
    return mRGBA;
}

前置摄像头

在这种情况下，你需要稍微操纵框架翻转他们，否则你的肖像模式将显示颠倒

@Override
public void onCameraViewStarted(int width, int height)
{
    mRGBAT = new Mat();
} 

@Override
public Mat onCameraFrame(CameraBridgeViewBase.CvCameraViewFrame inputFrame)
{
    mRGBA = inputFrame.rgba();
    // flipping to show portrait mode properly
    Core.flip(mRGBA, mRGBAT, 1);
    // releasing what's not anymore needed
    mRGBA.release();
    return mRGBAT;
}

最后，确保你添加到代码中的帧操作是真正需要的。它们的处理时间会降低性能，甚至会给你带来不必要的麻烦。我没有准确地检查，但我很肯定，在onCameraFrame()中转置矩阵是失真的根本原因

后置摄像头的主活动

package com.change.package.name;

import android.Manifest;
import android.content.pm.PackageManager;
import android.os.Bundle;
import android.util.Log;
import android.view.WindowManager;
import android.widget.Toast;

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

import org.opencv.android.BaseLoaderCallback;
import org.opencv.android.CameraBridgeViewBase;
import org.opencv.android.JavaCameraView;
import org.opencv.android.OpenCVLoader;
import org.opencv.core.Core;
import org.opencv.core.Mat;

public class MainActivity extends AppCompatActivity implements
        CameraBridgeViewBase.CvCameraViewListener2
{
    private static String TAG = "MainActivity";
    JavaCameraView javaCameraView;
    Mat mRGBA;
    private static final int MY_CAMERA_REQUEST_CODE = 100;
    int activeCamera = CameraBridgeViewBase.CAMERA_ID_BACK;

    BaseLoaderCallback baseLoaderCallback = new BaseLoaderCallback(MainActivity.this) {
        @Override
        public void onManagerConnected(int status)
        {
            if (status == BaseLoaderCallback.SUCCESS) {
                javaCameraView.enableView();
            } else {
                super.onManagerConnected(status);
            }
        }
    };

    static
    {
        if (OpenCVLoader.initDebug())
        {
            Log.d(TAG, "OpenCV is Configured or Connected successfully.");
        }
        else
        {
            Log.d(TAG, "OpenCV not Working or Loaded.");
        }
    }

    @Override
    protected void onCreate(Bundle savedInstanceState)
    {
        super.onCreate(savedInstanceState);
        setContentView(R.layout.activity_main);

        javaCameraView = (JavaCameraView) findViewById(R.id.my_camera_view);
        getWindow().addFlags(WindowManager.LayoutParams.FLAG_KEEP_SCREEN_ON);

        if (ContextCompat.checkSelfPermission(this, Manifest.permission.CAMERA)
                == PackageManager.PERMISSION_GRANTED) {
            Log.d(TAG, "Permissions granted");
            initializeCamera(javaCameraView, activeCamera);
        } else {
            Log.d(TAG, "Troubles");
            ActivityCompat.requestPermissions(this, new String[]{Manifest.permission.CAMERA}, MY_CAMERA_REQUEST_CODE);
            }
    }

    @Override
    public void onRequestPermissionsResult(int requestCode, @NonNull String[] permissions, @NonNull int[] grantResults) {
        super.onRequestPermissionsResult(requestCode, permissions, grantResults);
        if (requestCode == MY_CAMERA_REQUEST_CODE) {
            if (grantResults[0] == PackageManager.PERMISSION_GRANTED) {
                Toast.makeText(this, "Camera Permission granted", Toast.LENGTH_LONG).show();  
                initializeCamera(javaCameraView, activeCamera);
            } else {
                Toast.makeText(this, "Camera Permission denied", Toast.LENGTH_LONG).show();
            }
        }
    }

    private void initializeCamera(JavaCameraView javaCameraView, int activeCamera){
        javaCameraView.setCameraPermissionGranted();
        javaCameraView.setCameraIndex(activeCamera);

        javaCameraView.setVisibility(CameraBridgeViewBase.VISIBLE);
        javaCameraView.setCvCameraViewListener(this);
    }

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

    @Override
    public void onCameraViewStopped()
    {
        mRGBA.release();
    }

    @Override
    public Mat onCameraFrame(CameraBridgeViewBase.CvCameraViewFrame inputFrame)
    {
        // code for the back camera
        mRGBA = inputFrame.rgba();
        return mRGBA;
    }

    @Override
    public void onPointerCaptureChanged(boolean hasCapture) {

    }    

    @Override
    protected void onDestroy() {
        super.onDestroy();

        if (javaCameraView != null)
        {
            javaCameraView.disableView();
        }
    }

    @Override
    protected void onPause() {
        super.onPause();

        if (javaCameraView != null)
        {
            javaCameraView.disableView();
        }
    }    

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

        if (OpenCVLoader.initDebug())
        {
            Log.d(TAG, "OpenCV is Configured or Connected successfully.");
            baseLoaderCallback.onManagerConnected(BaseLoaderCallback.SUCCESS);
        }
        else
        {
            Log.d(TAG, "OpenCV not Working or Loaded.");
            OpenCVLoader.initAsync(OpenCVLoader.OPENCV_VERSION, this, baseLoaderCallback);
        }
    }
}

前置摄像头的主活动

package com.change.package.name;

import android.Manifest;
import android.content.pm.PackageManager;
import android.os.Bundle;
import android.util.Log;
import android.view.WindowManager;
import android.widget.Toast;

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

import org.opencv.android.BaseLoaderCallback;
import org.opencv.android.CameraBridgeViewBase;
import org.opencv.android.JavaCameraView;
import org.opencv.android.OpenCVLoader;
import org.opencv.core.Core;
import org.opencv.core.Mat;

public class MainActivity extends AppCompatActivity implements
        CameraBridgeViewBase.CvCameraViewListener2
{
    private static String TAG = "MainActivity";
    JavaCameraView javaCameraView;
    Mat mRGBA, mRGBAT;
    private static final int MY_CAMERA_REQUEST_CODE = 100;
    int activeCamera = CameraBridgeViewBase.CAMERA_ID_FRONT;

    BaseLoaderCallback baseLoaderCallback = new BaseLoaderCallback(MainActivity.this) {
        @Override
        public void onManagerConnected(int status)
        {
            if (status == BaseLoaderCallback.SUCCESS) {
                javaCameraView.enableView();
            } else {
                super.onManagerConnected(status);
            }
        }
    };

    static
    {
        if (OpenCVLoader.initDebug())
        {
            Log.d(TAG, "OpenCV is Configured or Connected successfully.");
        }
        else
        {
            Log.d(TAG, "OpenCV not Working or Loaded.");
        }
    }

    @Override
    protected void onCreate(Bundle savedInstanceState)
    {
        super.onCreate(savedInstanceState);
        setContentView(R.layout.activity_main);

        javaCameraView = (JavaCameraView) findViewById(R.id.my_camera_view);
        getWindow().addFlags(WindowManager.LayoutParams.FLAG_KEEP_SCREEN_ON);

        if (ContextCompat.checkSelfPermission(this, Manifest.permission.CAMERA)
                == PackageManager.PERMISSION_GRANTED) {
            Log.d(TAG, "Permissions granted");
            initializeCamera(javaCameraView, activeCamera);
        } else {
            Log.d(TAG, "Troubles");
            ActivityCompat.requestPermissions(this, new String[]{Manifest.permission.CAMERA}, MY_CAMERA_REQUEST_CODE);
            }
    }

    @Override
    public void onRequestPermissionsResult(int requestCode, @NonNull String[] permissions, @NonNull int[] grantResults) {
        super.onRequestPermissionsResult(requestCode, permissions, grantResults);
        if (requestCode == MY_CAMERA_REQUEST_CODE) {
            if (grantResults[0] == PackageManager.PERMISSION_GRANTED) {
                Toast.makeText(this, "Camera Permission granted", Toast.LENGTH_LONG).show();
                initializeCamera(javaCameraView, activeCamera);
            } else {
                Toast.makeText(this, "Camera Permission denied", Toast.LENGTH_LONG).show();
            }
        }
    }

    private void initializeCamera(JavaCameraView javaCameraView, int activeCamera){
        javaCameraView.setCameraPermissionGranted();
        javaCameraView.setCameraIndex(activeCamera);   
        javaCameraView.setVisibility(CameraBridgeViewBase.VISIBLE);
        javaCameraView.setCvCameraViewListener(this);
    }

    @Override
    public void onCameraViewStarted(int width, int height)
    {
        mRGBAT = new Mat();
    }

    @Override
    public void onCameraViewStopped()
    {
        mRGBA.release();
    }

    @Override
    public Mat onCameraFrame(CameraBridgeViewBase.CvCameraViewFrame inputFrame)
    {
        // code for the front camera
        mRGBA = inputFrame.rgba();
        // flipping to show portrait mode properly
        Core.flip(mRGBA, mRGBAT, 1);
        mRGBA.release();
        return mRGBAT;
    }

    @Override
    public void onPointerCaptureChanged(boolean hasCapture) {

    }    

    @Override
    protected void onDestroy() {
        super.onDestroy();

        if (javaCameraView != null)
        {
            javaCameraView.disableView();
        }
    }

    @Override
    protected void onPause() {
        super.onPause();

        if (javaCameraView != null)
        {
            javaCameraView.disableView();
        }
    }    

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

        if (OpenCVLoader.initDebug())
        {
            Log.d(TAG, "OpenCV is Configured or Connected successfully.");
            baseLoaderCallback.onManagerConnected(BaseLoaderCallback.SUCCESS);
        }
        else
        {
            Log.d(TAG, "OpenCV not Working or Loaded.");
            OpenCVLoader.initAsync(OpenCVLoader.OPENCV_VERSION, this, baseLoaderCallback);
        }
    }
}
赞(0）分享  回复(0）举报  2022-11-24
pvabu6sv

pvabu6sv2#

请尝试将其添加到MainActivity.java

@Override
    public void onPreviewFrame(byte[] data, Camera camera) {
        try {
            Data = data;
            if(flag == true) {
                fheight = camera.getParameters().getPreviewSize().height;
                fwidth = camera.getParameters().getPreviewSize().width;
                flag = false;
            }
        } catch (Exception e) {
        }
    }
赞(0）分享  回复(0）举报  2022-11-24
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