accent which leads to misidentification of speaker
which ultimately results in performance degrada-
tion of recognizer.
There are various feature extraction techniques
which claims to be robust while performing in such
environmental conditions. As far as pre-processing
stage is concerned, Linear Predictive analysis (LPC)
is assumed to be the first step of feature extraction
and other robust cepstral feature derived from lin-
ear predictive coefficients are then utilized.
Linear Prediction of Speech:
Since speech is produced by the movement of ana-
tomical structures such as vocal cords, vocal tract,
nasal cavity, tongue, and lips. Linear model of
speech is first proposed by Fant in late 1950s where
the glottal pulse, vocal tract, and radiation are indi-
vidually modeled as linear filters. A complete model
of speech production is shown in the figure.
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