P2Mark: Plug-and-play Parameter-intrinsic Watermarking for Neural Speech Generation

Recently, a large number of advanced neural speech generation methods have emerged in the open-source community. Although this has facilitated the application and development of technology, it has also increased the difficulty of preventing the abuse of generated speech and protecting copyrights. Audio watermarking technology is an effective method for proactively protecting generated speech, but when the source codes and model weights of the neural speech generation methods are open-sourced, audio watermarks based on previous watermarking methods can be easily removed or manipulated. This paper proposes a Plug-and-play Parameter-intrinsic WaterMarking (P2Mark) method for neural speech generation system protection. The main advantage of P2Mark is that the watermark information is flexibly integrated into the neural speech generation model in the form of parameters by training a watermark adapter rather than injecting the watermark into the model in the form of features. After the watermark adapter with the watermark embedding is merged with the pre-trained generation model, the watermark information cannot be easily removed or manipulated. Therefore, P2Mark will be a reliable choice for proactively tracing and protecting the copyrights of neural speech generation models in open-source white-box scenarios. We validated P2Mark on two main types of decoders in neural speech generation: vocoder and codec. Experimental results show that P2Mark achieves performance comparable to state-of-the-art audio watermarking methods that cannot be used for open-source white-box protection scenarios in terms of watermark extraction accuracy, watermark imperceptibility, and robustness.