title: Joint Dictionary Learning-Based Non-Negative Matrix Factorization for Voice Conversion to Improve Speech Intelligibility After Oral Surgery.
abstract: Objective:This paper focuses on machine learning based voice conversion (VC) techniques for improving the speech intelligibility of surgical patients who have had parts of their articulators removed. Because of the removal of parts of the articulator, a patient's speech may be distorted and difficult to understand. To overcome this problem, VC methods can be applied to convert the distorted speech such that it is clear and more intelligible. To design an effective VC method, two key points must be considered: 1) the amount of training data may be limited (because speaking for a long time is usually difficult for postoperative patients); 2) rapid conversion is desirable (for better communication).Methods:We propose a novel joint dictionary learning based non-negative matrix factorization (JD-NMF) algorithm. Compared to conventional VC techniques, JD-NMF can perform VC efficiently and effectively with only a small amount of training data.Results:The experimental results demonstrate that the proposed JD-NMF method not only achieves notably higher short-time objective intelligibility (STOI) scores (a standardized objective intelligibility evaluation metric) than those obtained using the original unconverted speech but is also significantly more efficient and effective than a conventional exemplar-based NMF VC method.Conclusion:The proposed JD-NMF method may outperform the state-of-the-art exemplar-based NMF VC method in terms of STOI scores under the desired scenario.Significance:We confirmed the advantages of the proposed joint training criterion for the NMF-based VC. Moreover, we verified that the proposed JD-NMF can effectively improve the speech intelligibility scores of oral surgery patients.Objective:This paper focuses on machine learning based voice conversion (VC) techniques for improving the speech intelligibility of surgical patients who have had parts of their articulators removed. Because of the removal of parts of the articulator, a patient's speech may be distorted and difficult to understand. To overcome this problem, VC methods can be applied to convert the distorted speech such that it is clear and more intelligible. To design an effective VC method, two key points must be considered: 1) the amount of training data may be limited (because speaking for a long time is usually difficult for postoperative patients); 2) rapid conversion is desirable (for better communication).Methods:We propose a novel joint dictionary learning based non-negative matrix factorization (JD-NMF) algorithm. Compared to conventional VC techniques, JD-NMF can perform VC efficiently and effectively with only a small amount of training data.Results:The experimental results demonstrate that the proposed JD-NMF method not only achieves notably higher short-time objective intelligibility (STOI) scores (a standardized objective intelligibility evaluation metric) than those obtained using the original unconverted speech but is also significantly more efficient and effective than a conventional exemplar-based NMF VC method.Conclusion:The proposed JD-NMF method may outperform the state-of-the-art exemplar-based NMF VC method in terms of STOI scores under the desired scenario.Significance:We confirmed the advantages of the proposed joint training criterion for the NMF-based VC. Moreover, we verified that the proposed JD-NMF can effectively improve the speech intelligibility scores of oral surgery patients.
authors.affiliation: Department of Computer Science and Information EngineeringNational Taiwan University.
authors.forename: Szu-Wei
authors.initials: SW
authors.lastname: Fu
authors.affiliation: Department of Audiology and Speech Language PathologyMackay Medical College.
authors.forename: Pei-Chun
authors.initials: PC
authors.lastname: Li
authors.affiliation: Department of Electrical EngineeringYuan Ze University.
authors.forename: Ying-Hui
authors.initials: YH
authors.lastname: Lai
authors.affiliation: Mackay Memorial Hospital.
authors.forename: Cheng-Chien
authors.initials: CC
authors.lastname: Yang
authors.affiliation: Mackay Memorial Hospital.
authors.forename: Li-Chun
authors.initials: LC
authors.lastname: Hsieh
authors.affiliation: Research Center for Information Technology Innovation, Academia Sinica, Taipei, Taiwan, R.O.C.
authors.forename: Yu
authors.initials: Y
authors.lastname: Tsao
mesh_terms: D000465:Algorithms; D003143:Communication Devices for People with Disabilities; D006801:Humans; D000069550:Machine Learning; D008297:Male; D019647:Oral Surgical Procedures / Q000009:adverse effects*; D013065:Speech Intelligibility / Q000502:physiology*; D049250:Speech Recognition Software
keywords: Data models; Dictionaries; Spectrogram; Speech; Surgery; Training; Training data