Short‐Term Autocorrelation Analysis and Correlatograms of Spoken Digits Available to Purchase

Autocorrelation techniques provide a method of displaying speech sounds in a form which differs significantly from conventional sound spectrograms. The autocorrelation function ψ₁₁(τ), of a signal I(t) is defined by . Delay τ introduced in the speech signal appears as ordinate in these displays, time t as abscissa, and magnitude of the resulting correlation function ψ₁₁(τ) is shown by the density of the pattern. Characteristic features of the displays are discussed and evaluated in terms of the mechanism of the correlation process. Data considered are limited to the ten spoken digits one, two, ⋯ nine, “oh.”