我的安卓应用在一个带有JavaCameraView
的活动中使用opencv for android进行图像处理,这很好用。现在我想在后台做同样的图像处理,而不给用户显示任何预览。我尝试使用安卓服务。
通过以下代码,我可以在服务中成功加载OpenCV:
import org.opencv.android.BaseLoaderCallback;
import org.opencv.android.LoaderCallbackInterface;
import org.opencv.android.OpenCVLoader;
import android.app.Service;
import android.content.Intent;
import android.os.IBinder;
import android.util.Log;
public class CameraService extends Service {
private static final String TAG = "CameraService";
BaseLoaderCallback mLoaderCallback = new BaseLoaderCallback(CameraService.this) {
@Override
public void onManagerConnected(int status) {
switch (status) {
case LoaderCallbackInterface.SUCCESS: {
Log.i("", "OpenCV loaded successfully");
}
break;
default: {
super.onManagerConnected(status);
}
break;
}
}
};
@Override
public int onStartCommand(Intent intent, int flags, int startId) {
if(OpenCVLoader.initAsync(OpenCVLoader.OPENCV_VERSION_2_4_4,
getApplicationContext(), mLoaderCallback)) {
Log.i(TAG, "Loaded OpenCV");
}
else
Log.i(TAG, "Couldn't load OpenCV");
return super.onStartCommand(intent, flags, startId);
}
@Override
public IBinder onBind(Intent intent) {
return null;
}
}
但是我不知道如何像在以前的活动中一样抓取帧,例如
onCameraFrame()
?
在那里,我已经实现了CvCameraViewListener2
,但没有在我的服务中实现,因为它需要一个CameraBridgeViewBase
,而我不想再显示它。
我该如何在后台进行图像处理呢?更新-> 2
我添加了一个runnable来抓取你告诉我的帧。 现在加载OpenCV并连接到摄像头都很好。但在抓取任何帧之前,它会跳过帧并中止,因为应用程序在主线程上做了太多的工作。
这是我的整个相机服务:
public final class MyService extends Service {
private static final String TAG = MyService.class.getSimpleName();
private boolean mStopThread;
private Thread mThread;
private VideoCapture mCamera;
private int mCameraIndex = -1;
BaseLoaderCallback mLoaderCallback = new BaseLoaderCallback(this) {
@Override
public void onManagerConnected(int status) {
switch (status) {
case LoaderCallbackInterface.SUCCESS: {
Log.i("", "OpenCV loaded successfully");
try {
if (!connectCamera(640, 480))
Log.e(TAG, "Could not connect camera");
else
Log.d(TAG, "Camera successfully connected");
} catch (Exception e) {
Log.e(TAG, "MyServer.connectCamera throws an exception: " + e.getMessage());
}
}
break;
default: {
super.onManagerConnected(status);
}
break;
}
}
};
@Override
public int onStartCommand(Intent intent, int flags, int startId) {
if(OpenCVLoader.initAsync(OpenCVLoader.OPENCV_VERSION_2_4_4, getApplicationContext(), mLoaderCallback))
Log.i(TAG, "Loaded OpenCV");
else
Log.i(TAG, "Couldn't load OpenCV");
return super.onStartCommand(intent, flags, startId);
}
public void onDestroy() {
this.disconnectCamera();
Log.d(TAG, "onDestroy");
super.onDestroy();
}
private boolean connectCamera(int width, int height) {
/* First step - initialize camera connection */
if (!initializeCamera(width, height)) {
Log.d(TAG, "initializeCamera failed");
return false;
} else {
Log.d(TAG, "initializeCamera successfully");
/* start update thread */
mThread = new Thread(new CameraWorker());
mThread.start();
return true;
}
}
private boolean initializeCamera(int width, int height) {
synchronized (this) {
if (mCameraIndex == -1)
mCamera = new VideoCapture(Highgui.CV_CAP_ANDROID);
else
mCamera = new VideoCapture(Highgui.CV_CAP_ANDROID + mCameraIndex);
if (mCamera == null)
return false;
if (mCamera.isOpened() == false)
return false;
/* Select the size that fits surface considering maximum size allowed */
Size frameSize = new Size(width, height);
mCamera.set(Highgui.CV_CAP_PROP_FRAME_WIDTH, frameSize.width);
mCamera.set(Highgui.CV_CAP_PROP_FRAME_HEIGHT, frameSize.height);
}
return true;
}
private void releaseCamera() {
synchronized (this) {
if (mCamera != null) {
mCamera.release();
}
}
}
private void disconnectCamera() {
// 1. Stop thread which updating the frames
// 2. Stop camera and release it
try {
mStopThread = true;
mThread.join();
} catch (InterruptedException e) {
e.printStackTrace();
} finally {
mThread = null;
mStopThread = false;
}
releaseCamera();
}
private class CameraWorker implements Runnable {
public void run() {
do {
if (!mCamera.grab()) {
Log.e(TAG, "Camera frame grab failed");
break;
}
Log.e(TAG, "Camera frame grabbed");
// img processing
} while (!mStopThread);
}
}
@Override
public IBinder onBind(Intent intent) {
return null; // Not used
}
}
我的日志:
11-29 12:28:24.370: D/OpenCVManager/Helper(5257): Init finished with status 0
11-29 12:28:24.370: D/OpenCVManager/Helper(5257): Unbind from service
11-29 12:28:24.380: D/OpenCVManager/Helper(5257): Calling using callback
11-29 12:28:24.380: I/(5257): OpenCV loaded successfully
11-29 12:28:24.380: D/OpenCV::camera(5257): CvCapture_Android::CvCapture_Android(0)
11-29 12:28:24.440: D/OpenCV_NativeCamera(5257): Connecting to CameraService v 3D
11-29 12:28:24.670: D/OpenCV_NativeCamera(5257): Instantiated new CameraHandler (0x75e4f29d, 0x71e178b8)
11-29 12:28:24.750: D/OpenCV_NativeCamera(5257): Starting preview
11-29 12:28:25.421: E/OpenCV_NativeCamera(5257): CameraHandler::doCall(void*, size_t): cameraCallback returns false (camera connection will be closed)
11-29 12:28:25.421: E/BufferQueue(5257): [unnamed-5257-0] dequeueBuffer: min undequeued buffer count (2) exceeded (dequeued=11 undequeudCount=0)
11-29 12:28:25.431: E/BufferQueue(5257): [unnamed-5257-0] dequeueBuffer: min undequeued buffer count (2) exceeded (dequeued=10 undequeudCount=1)
11-29 12:28:25.451: D/OpenCV_NativeCamera(5257): Preview started successfully
11-29 12:28:25.451: D/OpenCV_NativeCamera(5257): CameraHandler::setProperty(0, 640.000000)
11-29 12:28:25.451: D/OpenCV_NativeCamera(5257): CameraHandler::setProperty(1, 480.000000)
11-29 12:28:25.451: D/MyService(5257): initializeCamera successfully
11-29 12:28:25.451: D/MyService(5257): Camera successfully connected
11-29 12:28:25.451: I/Choreographer(5257): Skipped 86 frames! The application may be doing too much work on its main thread.
11-29 12:28:25.471: A/libc(5257): @@@ ABORTING: LIBC: HEAP MEMORY CORRUPTION IN tmalloc_small
11-29 12:28:25.471: A/libc(5257): Fatal signal 11 (SIGSEGV) at 0xdeadbaad (code=1), thread 5257 ()
出了什么问题,我现在该怎么办?