Speech Breathing in Virtual Humans: An Interactive Model and Empirical Study

Human speech production requires the dynamic regulation of air through the vocal system. While virtual character systems commonly are capable of speech output, they rarely take breathing during speaking - speech breathing - into account. We believe that integrating dynamic speech breathing systems in virtual characters can significantly contribute to augmenting their realism. Here, we present a novel control architecture aimed at generating speech breathing in virtual characters. This architecture is informed by behavioral, linguistic and anatomical knowledge of human speech breathing. Based on textual input and controlled by a set of low-and high-level parameters, the system produces dynamic signals in real-time that control the virtual character's anatomy (thorax, abdomen, head, nostrils, and mouth) and sound production (speech and breathing). In addition, we perform a study to determine the effects of including breathing-motivated speech movements, such as head tilts and chest expansions during dialogue on a virtual character, as well as breathing sounds. This study includes speech that is generated both from a text-to-speech engine as well as from recorded voice.