Question

首先让我说，如果图像拍摄间隔超过1秒，它就可以了。例如，每2秒拍一张照片就可以了。但每隔一秒拍一张照片有时会抛出java.lang.RuntimeException: takePicture failed。什么可能导致这种行为？

以下是我使用的代码，它位于服务：

@Override
public void onCreate()
{
    super.onCreate();
    prefs = getSharedPreferences("general",Context.MODE_PRIVATE);
    handler = new Handler();

    shotInterval = prefs.getInt(getString(R.string.prefs_int_imageShootingFrequency),1);

    if (!getPackageManager().hasSystemFeature(PackageManager.FEATURE_CAMERA)) {
        Toast.makeText(this, "No camera on this device", Toast.LENGTH_LONG).show();
    } else {
        cameraId = findBackFacingCamera();
        if (cameraId < 0) {
            Toast.makeText(this, "No front facing camera found.",Toast.LENGTH_LONG).show();
        } else {
            camera = Camera.open(cameraId);
        }
    }

    cameraParameters = camera.getParameters();
    cameraParameters.setFocusMode(Camera.Parameters.FOCUS_MODE_CONTINUOUS_PICTURE); //set camera to continuously auto-focus
    camera.setParameters(cameraParameters);

    pictureTaker.run(); // Start looping
}

Runnable pictureTaker = new Runnable() {
    @Override
    public void run() {
        try {
            takePicture();
        } finally {
            // 100% guarantee that this always happens, even if
            // your update method throws an exception
            handler.postDelayed(pictureTaker, shotInterval*1000);
        }
    }
};

private void takePicture(){
    SurfaceView view = new SurfaceView(this);
    try {
        camera.setPreviewDisplay(view.getHolder());
        camera.startPreview();
        camera.takePicture(null, null,new PhotoHandler(getApplicationContext()));
    } catch (IOException e) {
        e.printStackTrace();
    }
}

Answer 1

您应该从onPictureTaken()回调中启动postDelayed()。您可以在调用takePicture()时检查系统定时器并分别减少延迟，以保持1000ms重复，但可能偶尔会有一次，此延迟将达到0。

Android相机每秒都无法拍照

1 个答案: