How To Detect The Corners / Center X, Y Coordinates Using Google's Face Api?

Good day all, I am using Google's new Face API (Link here) which works with improved FaceDetection. One of the things you get back is a List of Landmark objects, each of which has

Solution 1:

Coordinates are pixel coordinates of the image.

These coordinates can be negative if the face extends beyond the top and/or the left edges of the image. Even though the head may not be entirely within the photo, the face detector will estimate the bounding box of the face beyond the image bounds based upon what is visible.