Editing Hidden Markov Models in Speech Synthesis (section)

=== Emotion and Intonation Synthesis ===
Integrating emotion and intonation information into the HMM model to achieve more rich and vivid speech synthesis, allowing synthesized speech to convey a broader range of emotional nuances and expressions. Key innovations in emotion and intonation synthesis in the domain of speech synthesis with HMMs primarily focus on model structure, feature extraction, and the use of emotion-annotated data. These innovations aim to make synthesized speech more emotionally expressive and closer to natural speech. These innovations have significantly improved HMM models in emotion and intonation synthesis, providing important insights and methods for achieving more rich and natural speech synthesis.

==== Emotional Modeling ====
# Emotion-Driven HMM Model: Designing an emotion-driven HMM model that takes emotion tags as input features, enabling the model to adjust synthetic speech characteristics based on emotional information for emotional synthesis. [Mills et al., 2012]<ref>Mills, G., & Schuller, B. W. (2012). [https://ieeexplore.ieee.org/document/6267902/ HMM-based synthesis of emotional speech with multi-formant filter representation]. In Proceedings of the 4th International Workshop on Emotion Corpora and Recognition (pp. 9-14).</ref>
# Modeling Emotion in a Multidimensional Space: Treating emotion as a multi-dimensional space and synthesizing different emotions by modeling speech feature distribution in this space. [Schuller et al., 2003]<ref>Schuller, B., Batliner, A., Seppi, D., Steidl, S., Vogt, T., Wagner, J., ... & Devillers, L. (2003). [https://ieeexplore.ieee.org/document/1234102/ The relevance of feature type for the automatic classification of emotional user states: Low level descriptors and functionals]. In European Conference on Speech Communication and Technology.</ref>

==== Intonation Modeling ====
# Intonation Modeling Based on Prosodic Patterns: Introducing prosodic pattern modeling to simulate intonation by adjusting pitch and volume. [Hunt and Black, 1996]<ref>Hunt, A., & Black, A. (1996). [https://ieeexplore.ieee.org/document/547974/ Unit selection in a concatenative speech synthesis system using a large speech database]. In Proceedings of the IEEE International Conference on Acoustics, Speech and Signal Processing (pp. 373-376).</ref>
# F0 Profile Modeling: Controlling intonation in speech synthesis by modeling the F0 (fundamental frequency) profile, representing pitch changes in sound. [Tóth and Bánhalmi, 2011]<ref>Tóth, L., & Bánhalmi, A. (2011). [https://ieeexplore.ieee.org/document/6118115/ HMM-based synthesis of F0 contours for TTS]. In Proceedings of the Annual Conference of the International Speech Communication Association (INTERSPEECH) (pp. 749-752).</ref>