try to make some Arithmetic Operations to enhance images

Question

I am trying to make some image enhancement using opencv here's my code:

def enhancement(img):
   matrix=np.ones((224,224),dtype='uint8')*50
   img1=cv2.add(img,matrix)
   img2=cv2.subtract(img,matrix)
   return img1,img2

so whenever i try to enhance my image like this

img=cv2.imread(imgpath)
img=cv2.resize(img,(224,224))
img1,img2=enhancement(img)

it gives me this error

cv2.error: OpenCV(4.5.5) D:\a\opencv-python\opencv-python\opencv\modules\core\src\arithm.cpp:650: error: (-209:Sizes of input arguments do not match) The operation is neither 'array op array' (where arrays have the same size and the same number of channels), nor 'array op scalar', nor 'scalar op array' in function 'cv::arithm_op'

So can anyone help me