多次resize操作+python

def resize(image, size_num):
    delm=max( image.shape[1], image.shape[0])
    if delm>size_num:
       multiple = delm/size_num
       ss=1
       hh_big=image.shape[1]
       ww_big=image.shape[0]
       while ss<=multiple and multiple>1.0:
             ss=ss+0.5
             image=cv2.resize(image, (int(hh_big/ss),  int(ww_big/ss)), interpolation=cv2.INTER_AREA)
    else:
       multiple = size_num/delm
       ss=1
       hh_big=image.shape[1]
       ww_big=image.shape[0]
       while ss<=multiple and multiple>1.0:
             ss=ss+0.5
             image=cv2.resize(image, (int(hh_big*ss),  int(ww_big*ss)), interpolation=cv2.INTER_CUBIC)
    image=cv2.resize(image, (size_num,  size_num-50), interpolation=cv2.INTER_CUBIC)
    return image