“b7b1bda34f920ef457486fd7a494464c31540a4a”上不存在“paddlespeech/s2t/frontend/featurizer/audio_featurizer.py”
* Rewrite is_empty op to avoid unnecessary data transform. test=develop * Add the implementation of InferShape and InferVarType for is_empty op. test=develop * Rewrite is_empty op to avoid directly inherit OperatorBase. test=develop