An LP-based blind model for restoring bone-conducted speech

Due to the stability against the external noise, bone-conducted (BC) speech seems better to be used instead of noisy air-conducted speech in an extremely noisy environment. However the quality of bone-conducted speech is very low and restoring bone-conducted speech is a challenged topic in speech signal processing field. As the main issue to improve the BC speech, many studies try to model and resolve the degradation when the signal is conducted through bone transduction. In previous study, we proposed a linear prediction (LP) based blind-restoration model. In this paper, we therefore completely evaluated the proposed model in comparison with other models to find out whether our proposed model could adequately improve voice quality and the intelligibility of BC speech, using objective measures (LSD, MCD, and LCD) and carrying out Japanese word-intelligibility tests (JWITs), Vietnamese word-intelligibility tests (VWITs) and Modified Rhyme Tests (MRTs) for English. The results of experiments on different languages, i.e. Japanese, English and Vietnamese proved the practicability of blind-BC restoration.