Thiago Brito Bezerra
ABSTRACT
One of the main components of voice over IP technology is voice coding algorithm, known as vocoders. There is a wide variety of vocoders and some have better quality than others. This work aims to evaluate the quality of some open source vocoders, and as starting point the implementation of evaluation procedure defined by ITU-T Recommendation P.834 for thus obtain the parameter of impairment factor at 0% of packet loss (Ie). This parameter, specific to each vocoder, it is used by the E-Model (ITU-T Rec. G.107 [6]) for evaluation of the quality of speech on VoIP calls.
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Digital Library
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