Performance Comparison of Linear Prediction based Vocoders in Linux Platform
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International Journal of Engineering Trends and Technology (IJETT) |  |
| © 2014 by IJETT Journal | ||
| Volume-10 Number-11 |
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| Year of Publication : 2014 | ||
| Authors : Lani Rachel Mathew , Ancy S. Anselam , Sakuntala S. Pillai |
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 10.14445/22315381/IJETT-V10P310 |
Citation
Lani Rachel Mathew , Ancy S. Anselam , Sakuntala S. Pillai. "Performance Comparison of Linear Prediction based Vocoders in Linux Platform", International Journal of Engineering Trends and Technology (IJETT), V10(11),554-558 April 2014. ISSN:2231-5381. www.ijettjournal.org. published by seventh sense research group
Abstract
Linear predictive coders form an important class of speech coders. This paper describes the software level implementation of linear prediction based vocoders, viz. Code Excited Linear Prediction (CELP), Low-Delay CELP (LD-CELP) and Mixed Excitation Linear Prediction (MELP) at bit rates of 4.8 kb/s, 16 kb/s and 2.4 kb/s respectively. The C programs of the vocoders have been compiled and executed in Linux platform. Subjective testing with the help of Mean Opinion Score test has been performed. Waveform analysis has been done using Praat and Adobe Audition software. The results show that MELP and CELP produce comparable quality while the quality of LD-CELP coder is much higher, at the expense of higher bit rate.
References
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Keywords
Vocoder, linear prediction, code excited, low delay, mixed excitation, CELP, LD-CELP, MELP, Praat, Linux