java - OpenCV 应用程序 - Android 相机在 10 秒后崩溃
问题描述
背景
在这个应用程序中,我能够启动在 Android Studio 中开发的相机预览,旨在将 OpenCV 整合到其中。但是,我面临一个错误;相机预览只持续大约 10 秒,直到它崩溃并且应用程序关闭。有什么办法可以解决这个问题吗?这是我的代码;
MainActivity.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.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;
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)
{
mRGBA = new Mat(height, width, CvType.CV_8UC4);
}
@Override
public void onCameraViewStopped()
{
mRGBA.release();
}
@Override
public Mat onCameraFrame(CameraBridgeViewBase.CvCameraViewFrame inputFrame)
{
mRGBA = inputFrame.rgba();
mRGBAT = mRGBA.t();
Core.flip(mRGBA.t(), mRGBAT, 1);
Imgproc.resize(mRGBAT, mRGBAT, mRGBA.size());
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);
}
}
@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();
}
}
}
AndroidManifest.xml
<?xml version="1.0" encoding="utf-8"?>
<manifest xmlns:android="http://schemas.android.com/apk/res/android"
package="com.example.cv">
<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/AppTheme">
<activity android:name=".MainActivity">
<intent-filter>
<action android:name="android.intent.action.MAIN" />
<category android:name="android.intent.category.LAUNCHER" />
</intent-filter>
</activity>
</application>
</manifest>
activity_main.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>
解决方案
再见,
我对您的问题进行了进一步调查,以下是一些注意事项:
1 - 我已经在上一个答案onCameraFrame()
的评论中建议您在不再需要矩阵时立即释放其中的矩阵。如本答案或此处所述,忘记这一点可能会产生垃圾收集问题。您可以使用该方法显式调用此过程以发生Mat.release()
,就像用户在相同的答案中所做的那样。你试过了吗?从我的测试来看,尽管尚未修复错误
2,但它延长了 10 秒的相机寿命 - 相反,从这个答案中,我们可以理解转置太多次可能会产生其他麻烦。让我们看一下您的代码:
mRGBAT = mRGBA.t();
Core.flip(mRGBA.t(), mRGBAT, 1);
这绝对看起来像我们可以改进的东西。您首先分配给mRGBA.t()
,mRGBAT
但随后您再次要求计算mRGBA
调用时的转置矩阵Core.flip()
。结果已经存储在 中mRGBAT
,因此无需再次执行此类操作。然后你可以像这样解决这个问题:
mRGBAT = mRGBA.t();
Core.flip(mRGBAT, mRGBAT, 1);
3 -和 之间没有真正的区别,Mat.t()
但Core.transpose()
第一个是第二个的包装器,我们可以直接使用后者
将解决您的问题的整个代码段如下:
Mat mRGBA, mRGBAT, dst;
@Override
public void onCameraViewStarted(int width, int height)
{
mRGBAT = new Mat();
dst = new Mat();
}
@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;
}
周末愉快,
安东尼诺
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