diff --git a/issuu2epub.py b/issuu2epub.py
index a5ac0cc..db68174 100644
--- a/issuu2epub.py
+++ b/issuu2epub.py
@@ -86,9 +86,9 @@ def convert_image(image_path: Path) -> io.BytesIO:
         img.thumbnail(max_image_size, Image.Resampling.LANCZOS)
         img_byte_arr = io.BytesIO()
         img.save(img_byte_arr, format="JPEG", optimize=True, quality=target_quality)
-        img_byte_arr.seek(0)
+        img_byte_arr = img_byte_arr.getvalue()  # type: ignore[assignment]
 
-    return img_byte_arr
+    return img_byte_arr  # type: ignore[return-value]
 
 
 def generate_epub(