def METHOD_NAME(atracks, btracks):
    """
    Compute cost based on IoU
    :type atracks: list[STrack]
    :type btracks: list[STrack]
    :rtype cost_matrix np.ndarray
    """
    if (len(atracks) > 0 and isinstance(atracks[0], np.ndarray)) or (
        len(btracks) > 0 and isinstance(btracks[0], np.ndarray)
    ):
        atlbrs = atracks
        btlbrs = btracks
    else:
        atlbrs = [track.tlbr for track in atracks]
        btlbrs = [track.tlbr for track in btracks]
    _ious = ious(atlbrs, btlbrs)
    cost_matrix = 1 - _ious
    return cost_matrix