Define format

handler.py

@@ -25,10 +25,13 @@ class EndpointHandler():
                   "height": 768,
                   "width": 768}
 
-        img = self._pipe(**params).images[0]
+        img: Image = self._pipe(**params).images[0]
 
+        stream = BytesIO()
+        img.save(stream, format="jpeg")
         res = {"status": 200,
-               "image": base64.b64encode(img.tobytes()).decode("utf8")}
+               "image": base64.b64encode(stream.getvalue()).decode("utf8")
+               }
         return res
 
 if __name__ == "__main__":