Update app.py

app.py

@@ -15,7 +15,9 @@ examples=["teeth_01.png","teeth_02.png","teeth_03.png","teeth_04.png"]
 
 def load_image(image_file):
 	img = Image.open(image_file)
-	return img
+	img_gray = img.convert('L')
+	img_np = np.array(img_gray)
+	return img_np
 
 def convert_one_channel(img):
     #some images have 3 channels , although they are grayscale image