Relative Energy And Intelligibility Of Transient Speech Information
Sungyub D. Yoo, J.R. Boston, Jessica Durrant, Kristie Kovacyk, S. Karn, Susan Shaiman, A. El-Jaroudi, Ching-Chung Li · 2006
Consonants are recognized to dominate higher frequencies of the speech spectrum and to carry more information than vowels, but both demonstrate quasi-steady state (QSS) and transient components, such as vowel to consonant transitions. Fixed filters somewhat separate these effects, but probably not optimally, given diverse words, speakers, and situations, and we suggest that important speech information is contained in transient speech components. To study the relative intelligibility of transient versus steady-state components, we employed an algorithm based on time-frequency analysis to extract QSS energy from the speech signal, leaving a residual signal of predominantly transient components. Psychometric functions were measured for speech recognition of processed and unprocessed monosyllabic words. The transient components were found to account for approximately 2% of the energy of the original speech, yet were nearly equally intelligible. As hypothesized, the QSS components contained much greater energy while providing significantly less intelligibility.