  Expressive text-to-speech (TTS) can synthesize a new speaking style by
imiating prosody and timbre from a reference audio, which faces the following
challenges: (1) The highly dynamic prosody information in the reference audio
is difficult to extract, especially, when the reference audio contains
background noise. (2) The TTS systems should have good generalization for
unseen speaking styles. In this paper, we present a
\textbf{no}ise-\textbf{r}obust \textbf{e}xpressive TTS model (NoreSpeech),
which can robustly transfer speaking style in a noisy reference utterance to
synthesized speech. Specifically, our NoreSpeech includes several components:
(1) a novel DiffStyle module, which leverages powerful probabilistic denoising
diffusion models to learn noise-agnostic speaking style features from a teacher
model by knowledge distillation; (2) a VQ-VAE block, which maps the style
features into a controllable quantized latent space for improving the
generalization of style transfer; and (3) a straight-forward but effective
parameter-free text-style alignment module, which enables NoreSpeech to
transfer style to a textual input from a length-mismatched reference utterance.
Experiments demonstrate that NoreSpeech is more effective than previous
expressive TTS models in noise environments. Audio samples and code are
available at:
\href{http://dongchaoyang.top/NoreSpeech\_demo/}{http://dongchaoyang.top/NoreSpeech\_demo/}
