Android：java.lang.RuntimeException：takePicture 失败

我正在尝试在 SurfaceView 的 ontouchevent 中捕获图像。但是，每次触摸屏幕时，应用程序都会崩溃，并出现以下异常：

01-05 21:03:18.500: ERROR/AndroidRuntime(10367): FATAL EXCEPTION: main
        java.lang.RuntimeException: takePicture failed
        at android.hardware.Camera.native_takePicture(Native Method)
        at android.hardware.Camera.takePicture(Camera.java:1126)
        at android.hardware.Camera.takePicture(Camera.java:1071)
        at com.test.MotionDetector.CameraSurfaceView.onTouchEvent(CameraSurfaceView.java:107)
        at android.view.View.dispatchTouchEvent(View.java:7350)
        at android.view.ViewGroup.dispatchTransformedTouchEvent(ViewGroup.java:2470)
        at android.view.ViewGroup.dispatchTouchEvent(ViewGroup.java:2212)
        at android.view.ViewGroup.dispatchTransformedTouchEvent(ViewGroup.java:2470)
        at android.view.ViewGroup.dispatchTouchEvent(ViewGroup.java:2212)
        at android.view.ViewGroup.dispatchTransformedTouchEvent(ViewGroup.java:2470)
        at android.view.ViewGroup.dispatchTouchEvent(ViewGroup.java:2212)
        at com.android.internal.policy.impl.PhoneWindow$DecorView.superDispatchTouchEvent(PhoneWindow.java:2151)
        at com.android.internal.policy.impl.PhoneWindow.superDispatchTouchEvent(PhoneWindow.java:1480)
        at android.app.Activity.dispatchTouchEvent(Activity.java:2469)
        at com.android.internal.policy.impl.PhoneWindow$DecorView.dispatchTouchEvent(PhoneWindow.java:2099)
        at android.view.View.dispatchPointerEvent(View.java:7535)
        at android.view.ViewRootImpl.deliverPointerEvent(ViewRootImpl.java:3492)
        at android.view.ViewRootImpl.deliverInputEvent(ViewRootImpl.java:3424)
        at android.view.ViewRootImpl.doProcessInputEvents(ViewRootImpl.java:4534)
        at android.view.ViewRootImpl.enqueueInputEvent(ViewRootImpl.java:4512)
        at android.view.ViewRootImpl$WindowInputEventReceiver.onInputEvent(ViewRootImpl.java:4616)
        at android.view.InputEventReceiver.dispatchInputEvent(InputEventReceiver.java:171)
        at android.os.MessageQueue.nativePollOnce(Native Method)
        at android.os.MessageQueue.next(MessageQueue.java:125)
        at android.os.Looper.loop(Looper.java:124)
        at android.app.ActivityThread.main(ActivityThread.java:4921)
        at java.lang.reflect.Method.invokeNative(Native Method)
        at java.lang.reflect.Method.invoke(Method.java:511)
        at com.android.internal.os.ZygoteInit$MethodAndArgsCaller.run(ZygoteInit.java:1038)
        at com.android.internal.os.ZygoteInit.main(ZygoteInit.java:805)
        at dalvik.system.NativeStart.main(Native Method)

My code:

package com.nadim.MotionDetector;

import android.content.Context;
import android.hardware.Camera;
import android.os.Environment;
import android.util.Log;
import android.view.MotionEvent;
import android.view.SurfaceHolder;
import android.view.SurfaceView;
import android.widget.Toast;

import java.io.File;
import java.io.FileNotFoundException;
import java.io.FileOutputStream;
import java.io.IOException;
import java.text.SimpleDateFormat;
import java.util.Date;

public class CameraSurfaceView extends SurfaceView implements SurfaceHolder.Callback {

    private SurfaceHolder mHolder;
    private Camera mCamera;
    private Context context;

    public CameraSurfaceView(Context context, Camera camera) {
        super(context);
        this.context = context;
        mCamera = camera;

        // Install a SurfaceHolder.Callback so we get notified when the
        // underlying surface is created and destroyed.
        mHolder = getHolder();
        mHolder.addCallback(this);
        // deprecated setting, but required on Android versions prior to 3.0
        mHolder.setType(SurfaceHolder.SURFACE_TYPE_PUSH_BUFFERS);
    }


    public void surfaceCreated(SurfaceHolder holder) {
        // The Surface has been created, now tell the camera where to draw the preview.
        try {
            mCamera.setPreviewDisplay(holder);
            mCamera.startPreview();
        } catch (IOException e) {
            Log.d("MotionDetector", "Error setting camera preview: " + e.getMessage());
        }


    }

    public void surfaceDestroyed(SurfaceHolder holder) {
        // empty. Take care of releasing the Camera preview in your activity.
    }

    public void surfaceChanged(SurfaceHolder holder, int format, int w, int h) {
        // If your preview can change or rotate, take care of those events here.
        // Make sure to stop the preview before resizing or reformatting it.
        if (mHolder.getSurface() == null) {
            // preview surface does not exist
            return;
        }

        // stop preview before making changes
        try {
            mCamera.stopPreview();
        } catch (Exception e) {
            // ignore: tried to stop a non-existent preview
        }

        // set preview size and make any resize, rotate or
        // reformatting changes here

        // start preview with new settings
        try {
            mCamera.setPreviewDisplay(mHolder);
            mCamera.startPreview();

        } catch (Exception e) {
            Log.d("MotionDetector", "Error starting camera preview: " + e.getMessage());
        }
    }

    @Override
    public boolean onTouchEvent(MotionEvent event) {

        Toast.makeText(context, "Picture taken", Toast.LENGTH_SHORT).show();
        //System.gc(); tried this because it was suggested in a stackoverflow question but it didn't help.
        mCamera.takePicture(null, mPicture, mPicture);
        return true; //processed
    }


    private Camera.PictureCallback mPicture = new Camera.PictureCallback() {

        @Override
        public void onPictureTaken(byte[] data, Camera camera) {

            File pictureFile = getOutputMediaFile();
            if (pictureFile == null) {
                return;
            }

            try {
                FileOutputStream fos = new FileOutputStream(pictureFile);
                fos.write(data);
                fos.close();
            } catch (FileNotFoundException e) {
                Log.d("MotionDetector", "File not found: " + e.getMessage());
            } catch (IOException e) {
                Log.d("MotionDetector", "Error accessing file: " + e.getMessage());
            }
        }
    };

    private static File getOutputMediaFile() {
        File mediaStorageDir = new File(Environment.getExternalStorageDirectory(), "motiondetect");
        if (!mediaStorageDir.exists()) {
            if (!mediaStorageDir.mkdirs()) {
                Log.d("MyCameraApp", "failed to create directory");
                return null;
            }
        }
        // Create a media file name
        String timeStamp = new SimpleDateFormat("yyyyMMdd_HHmmss").format(new Date());
        File mediaFile;
        mediaFile = new File(mediaStorageDir, timeStamp + ".jpg");

        return mediaFile;
    }
}

使用的权限和功能：

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

我不知道为什么会发生崩溃。许多其他主题建议首先调用 Camera.startPreview。我正在这样做，但这并不能解决问题。

拍照前的LogCat：

01-05 21:45:57.667: WARN/ActivityManager(754): No content provider found for permission revoke: file:///data/local/tmp/com.test.MotionDetector
01-05 21:45:57.667: WARN/ActivityManager(754): No content provider found for permission revoke: file:///data/local/tmp/com.test.MotionDetector
01-05 21:45:57.687: INFO/ActivityManager(754): Force stopping com.test.MotionDetector appid=10103 user=-1: uninstall pkg
01-05 21:45:57.687: INFO/ActivityManager(754): Killing 4264:com.test.MotionDetector/u0a103 (adj 7): stop com.test.MotionDetector
01-05 21:45:57.687: INFO/ActivityManager(754): Force finishing activity ActivityRecord{437a6678 u0 com.test.MotionDetector/.MotionDetectActivity t144}
01-05 21:45:57.697: WARN/InputDispatcher(754): channel '42adff40 com.test.MotionDetector/com.test.MotionDetector.MotionDetectActivity (server)' ~ Consumer closed input channel or an error occurred.  events=0x9
01-05 21:45:57.697: ERROR/InputDispatcher(754): channel '42adff40 com.test.MotionDetector/com.test.MotionDetector.MotionDetectActivity (server)' ~ Channel is unrecoverably broken and will be disposed!
01-05 21:45:57.697: WARN/InputDispatcher(754): Attempted to unregister already unregistered input channel '42adff40 com.test.MotionDetector/com.test.MotionDetector.MotionDetectActivity (server)'
01-05 21:45:57.697: INFO/WindowState(754): WIN DEATH: Window{42adff40 u0 com.test.MotionDetector/com.test.MotionDetector.MotionDetectActivity}
01-05 21:45:57.757: INFO/PackageManager(754): Running dexopt on: com.test.MotionDetector
01-05 21:45:57.757: INFO/PackageManager(754): Package com.test.MotionDetector codePath changed from /data/app/com.test.MotionDetector-1.apk to /data/app/com.test.MotionDetector-2.apk; Retaining data and using new
01-05 21:45:57.807: INFO/ActivityManager(754): Force stopping com.test.MotionDetector appid=10103 user=-1: update pkg
01-05 21:45:57.807: WARN/PackageManager(754): Code path for pkg : com.test.MotionDetector changing from /data/app/com.test.MotionDetector-1.apk to /data/app/com.test.MotionDetector-2.apk
01-05 21:45:57.807: WARN/PackageManager(754): Resource path for pkg : com.test.MotionDetector changing from /data/app/com.test.MotionDetector-1.apk to /data/app/com.test.MotionDetector-2.apk
01-05 21:45:57.937: INFO/ActivityManager(754): Force stopping com.test.MotionDetector appid=10103 user=0: pkg removed
01-05 21:45:57.987: DEBUG/BackupManagerService(754): Received broadcast Intent { act=android.intent.action.PACKAGE_REMOVED dat=package:com.test.MotionDetector flg=0x4000010 (has extras) }
01-05 21:45:58.047: DEBUG/BackupManagerService(754): Received broadcast Intent { act=android.intent.action.PACKAGE_ADDED dat=package:com.test.MotionDetector flg=0x4000010 (has extras) }
01-05 21:45:58.567: INFO/Icing.InternalIcingCorporaProvider(12750): Updating corpora: A: com.test.MotionDetector, C: MAYBE
01-05 21:45:58.647: DEBUG/PackageAddedReceiver(1086): package added com.test.MotionDetector
01-05 21:45:58.737: INFO/ActivityManager(754): START u0 {flg=0x10000000 cmp=com.test.MotionDetector/.MotionDetectActivity} from pid 4578
01-05 21:45:58.777: INFO/ActivityManager(754): Start proc com.test.MotionDetector for activity com.test.MotionDetector/.MotionDetectActivity: pid=4630 uid=10103 gids={50103, 1028, 1015}
01-05 21:45:59.627: INFO/ActivityManager(754): Displayed com.test.MotionDetector/.MotionDetectActivity: +861ms (total +972ms)
01-05 21:45:59.657: INFO/WindowManager(754): Screen frozen for +869ms due to Window{43cb77a8 u0 com.test.MotionDetector/com.test.MotionDetector.MotionDetectActivity}

假设您希望保存 jpeg，则不需要原始回调，因此 更改对 takePicture() 的调用：

mCamera.takePicture(null, mPicture, mPicture);

to

mCamera.takePicture(null, null, mPicture);

在你的 onTouchEvent() 中。这将使用 jpeg 图片回调。

调用 takePicture() 也会导致预览停止，因此如果您想拍摄更多照片或重新启动预览，您可能需要在 onPictureTaken() 回调中再次调用 startPreview()。

另外，在 onTouchEvent() 中，您可能会收到多个事件，因此请筛选出适合您的事件：

@Override
public boolean onTouchEvent(MotionEvent event) {
    Toast.makeText(context, "Picture taken", Toast.LENGTH_SHORT).show();
    //System.gc(); tried this because it was suggested in a stackoverflow question but it didn't help.

    switch(event.getAction()) {
        case MotionEvent.ACTION_DOWN:
            // A pressed gesture has started, the motion contains the initial starting location
            break;

        case MotionEvent.ACTION_UP:
            // A pressed gesture has finished, the motion contains the final release location 
            // as well as any intermediate points since the last down or move event.

            mCamera.takePicture(null, mPicture, mPicture);

            break;

        default:
            break;
    }

    return true; //processed
}

如果你把 takePicture() 放在 ACTION_DOWN 中，当你触摸屏幕时它就会被调用，而当你放在 ACTION_UP 中时，它会在你移开手指时发生。看看哪一个适合您。