As one of the most mature technologies for AI applications, intelligent voice technology is developing rapidly in the fields of smart home, smart vehicle, and smart wearables. In 2022, the scale of the global intelligent voice industry will reach 35.12 billion US dollars, maintaining a high growth rate of 33.1%. Speech synthesis, also known as Text to Speech (TTS) technology, is an important research direction in the field of speech processing, which aims to allow machines to generate natural and beautiful human speech. Speech synthesis technology can be applied to different scenarios alone, or it can be embedded into the overall solution of voice interaction as a tail link. Speech synthesis technology is internally divided into front-end and back-end. The front-end is mainly responsible for language analysis and processing of text, and its processing content mainly includes language, word segmentation, part-of-speech prediction, polyphonic word processing, prosody prediction, emotion, etc.

According to the "Digital Virtual Human Depth Industry Report", by 2030, the overall market size of China's digital virtual human will reach 270 billion. The digital virtual human has the appearance of a human being, and even the fineness of the skin is close to that of a real person. It has human behavior and can be expressed through language, facial expressions or body movements; it has human thoughts and can interact with human beings in real time, which is almost the same as human beings. The mainstream technology-driven routes of virtual digital humans are divided into AI-driven and human-driven digital human. Human-driven digital people are driven by real people. The main principle is that the real person communicates with the user in real time according to the user video sent by the video surveillance system, and at the same time, the expression and action of the real person are presented on the virtual digital human image through the motion capture collection system, so as to interact with the user.