diff --git a/backend/utils.py b/backend/utils.py
index b50b648..7f3bdfd 100644
--- a/backend/utils.py
+++ b/backend/utils.py
@@ -1,4 +1,5 @@
 from PIL import Image, UnidentifiedImageError
+from fastapi import HTTPException
 from pathlib import Path
 import io
 
@@ -13,13 +14,13 @@ def image_normalize(img: bytes) -> bytes:
         img.save(byte_arr, format='WEBP')
         return byte_arr.getvalue()
     except UnidentifiedImageError:
-        return 0
+        raise HTTPException(status_code=500, detail="Image file cannot be readed!")
+
 
 def save_image(img: bytes, dir: str, name: str) -> int:
     path = asset(dir)
     path.mkdir(exist_ok=True)
     img = image_normalize(img)
-    if img:
-        with open(Path(path, name+'.webp'), "wb") as file:
-            file.write(img)
-    return len(img)
\ No newline at end of file
+    with open(Path(path, name+'.jpg'), "wb") as file:
+        file.write(img)
+    return len(img)