Android Camera Preview在预览中拉伸，而不是在拍照后

我有一个应用程序，它以人像模式拍摄照片，并且一切正常，除了预览的大小与拍照后的图像大小不同。预览似乎失真且模糊，但充满了整个屏幕。拍照后，图像清晰，但比设备高度短或宽度更小（取决于所使用的设备）。

下面是一些图像示例和一些我正在使用的代码。

拍照之前：

拍照后：

相机预览代码以纵向显示：

protected int getRotationDegrees() {
    android.hardware.Camera.CameraInfo info = new android.hardware.Camera.CameraInfo();
    android.hardware.Camera.getCameraInfo(0, info);
    int rotation = ((WindowManager) mContext
            .getSystemService(Context.WINDOW_SERVICE)).getDefaultDisplay()
            .getRotation();
    int degrees = 0;

    switch (rotation) {
        case Surface.ROTATION_0:
            degrees = 0;
            break;
        case Surface.ROTATION_90:
            degrees = 90;
            break;
        case Surface.ROTATION_180:
            degrees = 180;
            break;
        case Surface.ROTATION_270:
            degrees = 270;
            break;
    }

    int result = (info.orientation - degrees + 360) % 360;
    return result;
}

拍照后旋转图像的代码：

Camera.PictureCallback mPictureCallback = new Camera.PictureCallback() {

    @Override
    public void onPictureTaken(byte[] data, Camera camera) {
        Bitmap pictureBitmap = null;

        pictureBitmap = BitmapFactory.decodeByteArray(data, 0, data.length);

        int rotationDegrees = mCameraPreview.getRotationDegrees();
        //mRotation = setCameraDisplayOrientation(MainActivity.this, Camera.CameraInfo.CAMERA_FACING_BACK, mCamera);
        Matrix matrix = new Matrix();
        matrix.postRotate(rotationDegrees);

        //Bitmap scaledBitmap = Bitmap.createScaledBitmap(pictureBitmap ,previewWidth ,previewHeight ,true);
        //Bitmap rotatedBitmap = Bitmap.createBitmap(scaledBitmap , 0, 0, scaledBitmap.getWidth(), scaledBitmap.getHeight(), matrix, true);
        Bitmap rotatedBitmap = Bitmap.createBitmap(pictureBitmap , 0, 0, pictureBitmap.getWidth(), pictureBitmap.getHeight(), matrix, true);

        //rotatedBitmap = BitmapFactory.decodeByteArray(data, 0, data.length);
        ImageView previewImage = (ImageView) findViewById(R.id.preview_image);
        previewImage.setImageBitmap(rotatedBitmap);
        mCameraPreview.setVisibility(View.INVISIBLE);
        mButtonCapture.setVisibility(View.INVISIBLE);
        //flCameraPreview.setVisibility(View.INVISIBLE);
    }
};

有人遇到过这个问题吗？我仍在尝试了解相机API。提前致谢！

编辑：我用来选择预览和图片大小的代码。

private Camera.Size getOptimalSize(List<Camera.Size> sizes, int h, int w) {
    final double ASPECT_TOLERANCE = 0.05;
    double targetRatio = (double) w/h;

    if (sizes == null) {
        return null;
    }

    Camera.Size optimalSize = null;

     double minDiff = Double.MAX_VALUE;

    int targetHeight = h;

    for (Camera.Size size : sizes) {
        double ratio = (double) size.width / size.height;
        if (Math.abs(ratio - targetRatio) > ASPECT_TOLERANCE) continue;
        if (Math.abs(size.height - targetHeight) < minDiff) {
            optimalSize = size;
            minDiff = Math.abs(size.height - targetHeight);
        }
    }

    if (optimalSize == null) {
        minDiff = Double.MAX_VALUE;
        for (Camera.Size size : sizes) {
            if (Math.abs(size.height - targetHeight) < minDiff) {
                optimalSize = size;
                minDiff = Math.abs(size.height - targetHeight);
            }
        }
    }

    return optimalSize;
}