Abstract: Presently, the researches on the action of human’s mouth shape in the world are
mainly carried out based on English words. However, such research based on Chinese words is
not so much. Connected with our predecessors’ researches, this paper puts forwards a sound
weighting control algorithm with the integration of the changing law of mouth shape and the time
control of Chinese label when doing Chinese pronunciation. We use this algorithm to analyze the
label in a sentence and a paragraph and compose a 3-dimensional model. This model can
synchronize the continuously changing mouth shape with the sounds. A transition sequence of
mouth shapes between two continuous mouth shapes is composed with the help of an interpolation
method using cosine function. Thus, the action of human mouth synchronized with Chinese
phonetics becomes more smooth and fluent.

Key words: Chinese phonetic synchronization, 3D mouth animation, weighted control algorithm