@ptrblck， i check the code which is the same as what in pytorch about the data pre-procession. And i found there are two ways to transform pytorch model to torch script, which is trace and annotation. And i use trace to do that. The official said that the trace would limit the control flow such as “if else”, which several exist in my code. i wonder is real the control flow was limited that the trace-torch script can’t get the same accuracy as pytorch did?