Triphone based unit selection for concatenative visual speech synthesis

Concatenative visual speech synthesis selects frames from a large recorded video database of mouth shapes to generate photo-realistic talking head sequences. The synthesized sequence must exhibit precise lip-sound synchronization and smooth articulation. The selection process for finding the best lip shapes has been computationally expensive [1], limiting the speed of the synthesis to far less than real time. In this paper, we propose a rapid unit selection approach based on triphone units. Experiments show that this algorithm can make the synthesis, excluding the rendering, 50 times faster than real-time on a standard desktop PC. We also developed a metric to test the quality of the synthesis objectively, and show that this measurement is consistent with subjective measurement results.