Fast Pitch Modelling for Cs-acelp Coder Using Fermat Number Tranforms
نویسندگان
چکیده
This paper presents a double improvements to reduce the speech coding complexity of the pitch prediction in a CodeExcited Linear Prediction (CELP ) coder. First, the pitch analysis structure is modified. A new fast Pitch Modelling by linear-Filtering (PMF ) procedure will determine the adaptive and stochastic codebook contributions of the excitation signal. Afterwards, an e cient implementation of the PMF CELP coding is proposed by using Number Theoretic Transforms which can significantly reduce the algorithm computation complexity.
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