Paavo Alku


Spectral modification for recognition of children’s speech undermismatched conditions
Hemant Kumar Kathania | Sudarsana Reddy Kadiri | Paavo Alku | Mikko Kurimo
Proceedings of the 23rd Nordic Conference on Computational Linguistics (NoDaLiDa)

In this paper, we propose spectral modification by sharpening formants and by reducing the spectral tilt to recognize children’s speech by automatic speech recognition (ASR) systems developed using adult speech. In this type of mismatched condition, the ASR performance is degraded due to the acoustic and linguistic mismatch in the attributes between children and adult speakers. The proposed method is used to improve the speech intelligibility to enhance the children’s speech recognition using an acoustic model trained on adult speech. In the experiments, WSJCAM0 and PFSTAR are used as databases for adults’ and children’s speech, respectively. The proposed technique gives a significant improvement in the context of the DNN-HMM-based ASR. Furthermore, we validate the robustness of the technique by showing that it performs well also in mismatched noise conditions.


Vowel Enhancement in Early Stage Spanish Esophageal Speech Using Natural Glottal Flow Pulse and Vocal Tract Frequency Warping
Rizwan Ishaq | Dhanananjaya Gowda | Paavo Alku | Begonya Garcia Zapirain
Proceedings of SLPAT 2015: 6th Workshop on Speech and Language Processing for Assistive Technologies