title: The effects of digital quantization error on speech intelligibility and perceived speech quality.
abstract: The effects of digital quantization error upon speech intelligibility and perceived speech quality, for normally hearing subjects, were investigated for digitized speech processed to simulate 6-, 8-, 10-, 12-, 14-, and 16-bit integer conversion and 2-, 3-, 4-, 5-, 6-, and 7-bit floating-point conversion. For the integer data, there were no significant differences in speech intelligibility for 8- to 16-bit conversion. Only 6-bit integer conversion at 55 dB SPL resulted in a significant degradation in speech intelligibility. For the floating-point data, there were no significant differences in speech intelligibility for 2- to 7-bit floating-point conversion. However, results of the perceived quality experiment appeared to be more sensitive to differences among the various conditions. Speech processed using 12-, 14-, and 16-bit integer conversion was judged to be superior to speech processed using the 6-, 8-, and 10-bit integer conditions. Speech processed using 5-, 6-, and 7-bit floating-point conversion was judged to be superior to speech processed using 2-, 3-, and 4-bit floating-point conversion.
authors.affiliation: Communication Sciences and Disorders, Brigham Young University.
authors.forename: R W
authors.initials: RW
authors.lastname: Harris
authors.forename: R H
authors.initials: RH
authors.lastname: Brey
authors.forename: Y S
authors.initials: YS
authors.lastname: Chang
authors.forename: B D
authors.initials: BD
authors.lastname: Soria
authors.forename: L M
authors.initials: LM
authors.lastname: Hilton
mesh_terms: D000162:Acoustics; D000703:Analog-Digital Conversion; D000704:Analysis of Variance; D004582:Electronics, Medical; D006310:Hearing Aids; D006801:Humans; D013065:Speech Intelligibility; D014833:Voice Quality