[...,1:2]

def yolo_boxes_to_corners(box_xy, box_wh):
    """Convert YOLO box predictions to bounding box corners."""
    box_mins = box_xy - (box_wh / 2.)
    box_maxes = box_xy + (box_wh / 2.)
    qq=box_mins[..., 1:2]  ### ###[...,1:2]只有最后一个维度会变，取第1列
    q=box_mins[..., 0:1]    ###只有最后一个维度会变，取第0列
    qqq=np.concatenate([qq,q],axis=3)
    return np.concatenate([
        box_mins[..., 1:2],  # y_min 
        box_mins[..., 0:1],  # x_min
        box_maxes[..., 1:2],  # y_max
        box_maxes[..., 0:1]  # x_max
    ])
    
a=np.random.randint(5,size=(19, 19, 5, 2))
b=np.random.randint(5,size=(19, 19, 5, 2))
c=yolo_boxes_to_corners(a,b)