Automatic measurement of intonation.

If speech intonation is only represented by an unprocessed series of pitch measurements, the interpretation can be hampered by three factors. First, because of the presence of unvoiced parts in an utterance, the continuously perceived pitch contour is disturbed by interruptions. Second, in many cases, speech is characterized by involuntary pitch perturbations that either cannot be heard at all, or do not contribute to the perception of intonation. Third, the perceptual meaning of a pitch movement depends upon its position within the syllable, in many cases with respect to the vowel onset. A correct interpretation of a pitch contour, therefore, requires the position of the vowel onsets to be known, too. These problems can be solved by interpolating the pitch at unvoiced parts from the adjacent pitch measurements, by removing all perceptually irrelevant details from the contour, and by indicating the vowel onsets. Besides presenting the procedures, a system will be presented which performs these tasks in real time, and which is currently used in an evaluation of its usefulness in teaching intonation to deaf persons. The applicability for the use of this intonation meter in training intonation of foreign languages will be indicated. [Work supported by Instituut voor Doven, St.–Michielsgestel, Netherlands.]