android - 使用 android camera2 API 显示相机提要

Question

我正在尝试创建一个非常简单的应用程序，它会在显示屏上显示从相机接收到的图片。我正在使用 camera2 API，因为我是新手，所以我尝试使用最新的技术。

我到达了调用 createCaptureSession() 的位置，然后 onConfigureFailed()接到电话，但我不知道问题出在哪里或如何找到它。

这是我的来源:

SurfaceView mSurfaceView;

@Override
protected void onCreate(Bundle savedInstanceState) {
    super.onCreate(savedInstanceState);

    Log.d(TAG, "onCreate() start");

    setContentView(R.layout.activity_main);

    mSurfaceView = (SurfaceView) findViewById(R.id.surfaceView);

}

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

    Log.d(TAG, "onResume() start");

    initCamera();
}

private void initCamera() {
    Log.d(TAG, "initCamera() start");
    CameraManager cameraManager = (CameraManager) getSystemService(Context.CAMERA_SERVICE);
    Log.d(TAG, "acquired cameraManager: " + cameraManager);

    String[] cameraIdList;
    try {
        cameraIdList = cameraManager.getCameraIdList();
    } catch (CameraAccessException e) {
        Log.e(TAG, "couldn't get camera list", e);
        return;
    }
    Log.d(TAG, "acquired cameraIdList: length: " + cameraIdList.length);

    if (cameraIdList.length == 0) {
        Log.w(TAG, "couldn't detect a camera");
        return;
    }

    String camera0Id = cameraIdList[0];

    Log.d(TAG, "chosen camera: " + camera0Id);

    try {
        cameraManager.openCamera(camera0Id, deviceCallback, null);
    } catch (CameraAccessException e) {
        Log.e(TAG, "couldn't open camera", e);
    }
    Log.d(TAG, "called cameraManager.openCamera()");
}

CameraDevice.StateCallback deviceCallback = new CameraDevice.StateCallback() {

    @Override
    public void onOpened(CameraDevice camera) {
        Log.d(TAG, "deviceCallback.onOpened() start");

        Surface surface = mSurfaceView.getHolder().getSurface();
        Log.d(TAG, "surface: " + surface);

        List<Surface> surfaceList = Collections.singletonList(surface);

        try {
            camera.createCaptureSession(surfaceList, sessionCallback, null);
        } catch (CameraAccessException e) {
            Log.e(TAG, "couldn't create capture session for camera: " + camera.getId(), e);
            return;
        }

    }

    @Override
    public void onDisconnected(CameraDevice camera) {
        Log.d(TAG, "deviceCallback.onDisconnected() start");
    }

    @Override
    public void onError(CameraDevice camera, int error) {
        Log.d(TAG, "deviceCallback.onError() start");
    }

};

CameraCaptureSession.StateCallback sessionCallback = new CameraCaptureSession.StateCallback() {
    @Override
    public void onConfigured(CameraCaptureSession session) {
        Log.i(TAG, "capture session configured: " + session);
    }

    @Override
    public void onConfigureFailed(CameraCaptureSession session) {
        Log.e(TAG, "capture session configure failed: " + session);
    }
};

输出是:

...﹕ onCreate() start
...﹕ onResume() start
...﹕ initCamera() start
...﹕ acquired cameraManager: android.hardware.camera2.CameraManager@5d68786
...﹕ acquired cameraIdList: length: 2
...﹕ chosen camera: 0
...﹕ called cameraManager.openCamera()
...﹕ deviceCallback.onOpened() start
...﹕ surface: Surface(name=null)/@0x52c91e3
...﹕ capture session configure failed: android.hardware.camera2.impl.CameraCaptureSessionImpl@1a8c7a99

以下内容在我的 AndroidManifest.xml 中:

<uses-permission android:name="android.permission.CAMERA" />
<uses-feature android:name="android.hardware.camera" />
<uses-feature android:name="android.hardware.camera2" />

Answer 1

你应该设置预览的大小

mSurfaceView.getHolder().setFixedSize(previewSize.getWidth(), previewSize.getHeight());