LPC Speech Examples

A common and popular use of LPC is for speech analysis, synthesis, and compression. The reason for this is that the voice can be viewed as a source-filter model, where a spectrally rich input (pulses from the vocal folds or noise from turbulence) excites a filter (the resonances of the vocal tract). LPC is another form of vocoder (voice coder) as discussed in Chapter 7, but since LPC filters are not fixed in frequency or shape, fewer bands are needed to dynamically model the changing speech spectral shape. 

LPC speech analysis/coding involves processing the signal in blocks and computing a set of filter coefficients for each block. Based on the slowly varying nature of speech sounds (the speech articulators can only move so fast), the coefficients are relatively stable for milliseconds at a time (typically 

LPC can be used for cross-synthesis, as described in Chapter 7, by keeping the time-varying filter coefficients and replacing the residual with some other 

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