(numpy.array, numpy.array, int) -> numpy.array, numpy.array, numpy.array Returns 3 lists of matches, unmatched_detections and unmatched_trackers

Computes IUO between two bboxes in the form [x1,y1,x2,y2]

Takes a bounding box in the form [x1,y1,x2,y2] and returns z in the form [x,y,s,r] where x,y is the centre of the box and s is the scale/area

Takes a bounding box in the centre form [x,y,s,r] and returns it in the form [x1,y1,x2,y2] where x1,y1 is the top left and x2,y2 is the botto