The confidence score for the primitive. It should be between 0 and 1.
Maximum abscissa of the bounding box (right edge). Must be strictly more than x_min.
Minimum abscissa of the bounding box (left edge). Must be strictly less than x_max.
Maximum ordinate of the bounding box (top edge). Must be strictly more than y_min.
Minimum ordinate of the bounding box (bottom edge). Must be strictly less than y_max.
A plain rectangle