Speech Watermarking Method Using McAdams Coefficient Based on Random Forest Learning

Entropy (Basel). 2021 Sep 25;23(10):1246. doi: 10.3390/e23101246.

Abstract

Speech watermarking has become a promising solution for protecting the security of speech communication systems. We propose a speech watermarking method that uses the McAdams coefficient, which is commonly used for frequency harmonics adjustment. The embedding process was conducted, using bit-inverse shifting. We also developed a random forest classifier, using features related to frequency harmonics for blind detection. An objective evaluation was conducted to analyze the performance of our method in terms of the inaudibility and robustness requirements. The results indicate that our method satisfies the speech watermarking requirements with a 16 bps payload under normal conditions and numerous non-malicious signal processing operations, e.g., conversion to Ogg or MP4 format.

Keywords: McAdams coefficient; machine learning for watermarking; random forest classifier; speech watermarking.