An improved 2.4kb/s mixed excitation linear prediction vocoder
Wenyuan Li · Journal of Circuits and Systems · 2007
In this paper,two improvements on 2.4kb/s Mixed-Excitation linear Prediction(MELP) vocoder are presented.The one is a new parameter named Energy to Differential Zero-crossing Rate which is used in adaptation of V/UV decision of transitional segments and low energy level speech segments.The second is a multi-path searching method for multi-stage vector quantization(MSVQ) of line spectral frequency.Subjective tests show that the intelligiblity and naturallity of improved MELP vocoder are preferable to that of the original one.