Computer Identification of Vowel Types

In a classical study of the vowel sounds of English, G. E. Peterson and H. L. Barney collected a large body of experimental data which related perceived vowel quality to measurements of the first three formant frequencies and the voice pitch. It is difficult for a computer to use this raw data to interpret vowel quality because the vowel types have complicated boundaries in the coordinate system of the physical measurements. This paper describes a coordinate transformation which simplifies these boundaries.