Figure 8

(Top plot) Audio signal corresponding to the following three Spanish utterances: “ Primero hay que aceptar y después optar ”, “ Pepita pasó esta tarde ”, “ Este atlas no es étnico ”. (Lower four plots) True (dashed line) and estimated (solid line) visual parameters associated with the audio signal, $o_{v_1}$: upper lip vertical movement, $o_{v_2}$: lip stretching, $o_{v_3}$: mouth opening control, and $o_{v_4}:$ lip corner movement.