Set the size of the annotation boxes and add aiming crosshair lines

[chaohong100]

I want to train YOLO to recognize the direction of objects. For that, I need to annotate prominent corners and the line connecting two annotated boxes will indicate the direction. It would be helpful if the corner is positioned at the center of the annotated box, and if a cross is displayed at the center of the box. Additionally, the annotated box needs to be of a fixed size.