change calculation

main.py

@@ -53,7 +53,7 @@ async def predict_image(file: UploadFile = File(...)):
         background_element = next((element for element in results if element['label'] == 'background'), None)
         
         if background_element:
-            background_area = calculate_mask_area(background_element['mask'])
+            background_area = calculate_mask_area(background_element['mask'], True)
         else:
             background_area = 0
         

utils/helpers.py

@@ -9,7 +9,10 @@ def image_to_base64(image: Image.Image) -> str:
     image.save(buffered, format="JPEG")
     return base64.b64encode(buffered.getvalue()).decode("utf-8")
 
-def calculate_mask_area(mask: Image.Image) -> int:
+def calculate_mask_area(mask: Image.Image, background=False) -> int:
     mask_array = np.array(mask)
-    non_zero_pixels = np.count_nonzero(mask_array)
+    if background:
+        non_zero_pixels = np.count_nonzero(mask_array == 0)
+    else:
+        non_zero_pixels = np.count_nonzero(mask_array)
     return non_zero_pixels