Phonetic vocoder assessment

Title A phonetic Vocoder for Very-Low-Rate Speech Coding

Phonetic vocoding with speaker adaptation

This paper describes a phonetic vocoding scheme which relies on speaker adaptation to capture important speaker characteristics. These are typically lost in phonetic vocoders which transmit only information about the phones which are recognized, together with some prosodic information. In our scheme, however, additional speaker characteristics are transmitted in vowel regions (average values of...

Towards a segmental vocoder driven by ultrasound and optical images of the tongue and lips

This article presents a framework for a phonetic vocoder driven by ultrasound and optical images of the tongue and lips for a “silent speech interface” application. The system is built around an HMM-based visual phone recognition step which provides target phonetic sequences from a continuous visual observation stream. The phonetic target constrains the search for the optimal sequence of diphon...

Intelligibility of degraded speech from smeared STRAIGHT spectrum

Intelligibility of degraded speech sounds has been investigated based on a new signal processing technique using a high-quality vocoder, STRAIGHT. This enables us to manipulate essential speech parameters for vocal tract filtering and glottal excitation. We report that the effect of spectral smearing on the intelligibility of Japanese fourmora words as an initial study. Results reveal that the ...

Syllable-based pitch encoding for low bit rate speech coding with recognition/synthesis architecture

Current HMM-based low bit rate speech coding systems work with phonetic vocoders. Pitch contour coding (on frame or phoneme level) is usually fairly orthogonal to other speech coding parameters. We make an assumption in our work that the speech signal contains supra-segmental cues. Hence, we present encoding of the pitch on the syllable level, used in the framework of a recognition/synthesis sp...