Update app.py

app.py

@@ -81,7 +81,7 @@ def recommend_glasses_tree(face_shape):
 
 # Preprocess function
 def preprocess_image(image):
-    img = np.array(image)
+    img = np.array(image, dtype=np.uint8)
     img = cv2.cvtColor(img, cv2.COLOR_RGB2BGR)
 
     results = mp_face_detection.process(cv2.cvtColor(img, cv2.COLOR_BGR2RGB))