Importance

Loading Importance Indicators...

Abstract

A method and system for determining the mouth features, i.e., the lip position and mouth opening, of an animated character. Lip position is the shape and position of the lips of the animated character. Mouth opening is the amount of opening between the lips of the animated character. A time-domain signal corresponding to the speech of the animated character may be digitally sampled. The sampled voice signal is separated into a number of frames of a specific time length. A Hamming window is applied to each frame to de-emphasize the boundary conditions of each frame. A linear predictive coding (LPC) technique is applied to each of the frames, resulting in a gain for each of the frames and a number of k coefficients, or reflection coefficients, including a voiced/nonvoiced coefficient and a pitch coefficient. The reflection coefficients for each frame are mapped to the Cepstral domain resulting in a number of Cepstral coefficients for each frame. The Cepstral coefficients are vector quantized to achieve a vector quantization result representing the character's lip position. For a predetermined number of frames, a local maximum and a local minimum of gain are found. The gain for each of the frames containing a local minimum is set to a fully closed mouth opening and the gain for each of the frames containing a local maximum is set to a fully open mouth opening. The vector quantization result and gain are applied to an empirically derived mapping function to determine the mouth features of the character.

Loading the Abstract Image...

First Claim