I use OpenCV's face detector with C++ for dlib's face alignment instead of dlib's detector because of slow speed.  

To use dlib's face alignment, I have to pass the detection rectangle to the face alignment function.  

However, I cannot do that even though dlib's detector is ok.  

Because `std::vector<rectangle> dets`is used in [dlib's sample code](http://dlib.net/face_landmark_detection_ex.cpp.html), I tried to assign as shown below, but I couldn't.  

Note that `detect_rect` is face detection rectangle by OpenCV's detector.  

```
dets[0].l = detect_rect.left;
dets[0].t = detect_rect.top;
dets[0].r = detect_rect.right;
dets[0].b = detect_rect.bottom;

```

Could you tell me any advice?

Thank you.