Coding effects on changes in formant frequencies in Japanese speech signals
Treść / Zawartość
This paper presents results of research on effects of lossy coding on formant frequencies for japanese speech signals. Additionally changes in pitch of the voice were inspected. For this research four most popular lossy coding standards were chosen, MP3, WMA, AAC and OGG, and compared to original WAVE files. Audio files were created by the author based on ITU-T P.501 recommendation in two sampling frequencies, 16 kHz and 48 kHz, and converted into chosen codecs. To extract the data from audio files, open license software Praat was used. Due to discovered differences in time duration between original and encoded files, that also differed between individual codecs, only OGG and WMA standards were compared directly. MP3 and AAC standards were divided into Japanese syllables, averaged and then compared into also averaged WAVE files. Results were additionally compared to FLAC lossless codec.
Bibliogr. 4 poz., 1 il. kolor., wykr.
- Wroclaw University of Science and Technology, Faculty of Electronics, Department of Acoustics and Multimedia, 50-370 Wroclaw, Wybrzeze Wyspianskiego 27, email@example.com
- Wroclaw University of Science and Technology, Faculty of Electronics, Department of Acoustics and Multimedia, 50-370 Wroclaw, Wybrzeze Wyspianskiego 27, firstname.lastname@example.org
- 1. S. Brachmański, Wybrane zagadnienia oceny jakości transmisji sygnału mowy, Wrocław: Oficyna Wydawnicza Politechniki Wrocławskiej, 2015.
- 2. ITU-T Recommendation P.501, Test signals for use in telephonometry, 2017.
- 3. ITU-T Recommendation P.800, Method for subjective determination of transmission quality, 1996.
- 4. M. Kucharski, Realization of Japanese sentences sets acoustical database for selected coding techniques, Wrocław, BSc Thesis, Wrocław University of Science and Technology, 2017.