The chronical dysphony is the result of neural, structural or pathological effects on the vocal cords or larynx and it causes
undesirable changes in the quality of speech. This paper presents a Mixed Excitation Linear Prediction (MELP) based system
that reconstructs normally phonated speech from dysphonic speech, while preserving the individuality of the patient. The proposed
system can be used as speech prosthesis for the patients who have lost the ability to produce voice. To reconstruct normally
phonated speech from dysphonic speech, pitch generation using the perceived pitch relationship with formant frequencies, formant
and voicing modification steps were performed for phonemes. The principle novelty of this study is to modify voiced phonemes’
acoustic features while preserving unvoiced ones. Therefore voiced-unvoiced detection is performed for each phoneme.
The proposed system is composed of three main parts. In the analysis phase the acoustic differences observed between normal
and dysphonic speech are determined. Acoustic parameters of the dysphonic speech’s voiced phonemes are modified in order to
obtain a synthetic speech that is closer to normal speech. Finally, enhanced speech is synthesized by MELP.
Keywords Dysphonic speech enhancement - MELP - Formant modification - Pitch and voicing generation