SPecXpc

Routine

void SPecXpc (const float ec[], float pc[], int Np)

Purpose

Convert prediction error filter coefficients to predictor coefficients

Description

              ec[0]  = 1 (not used)
     pc[0] = -ec[1]
          ...
  pc[Np-1] = -ec[Np]

Predictor coefficients are usually expressed algebraically as vectors with 1-offset indexing. The correspondence to the 0-offset C-arrays is as follows.

  p(1) <==> pc[0]       predictor coefficient corresponding to lag 1
  p(i) <==> pc[i-1]     1 <= i < Np

Parameters

-> const float ec[]

Prediction error (residual) filter coefficients (Np + 1 values). It is considered an error if ec[0] is not equal to 1.

<- float pc[]

Vector of predictor coefficients (Np values). These are the coefficients of the predictor filter, with pc[0] being the predictor coefficient corresponding to lag 1, and pc[Np-1] corresponding to lag Np.

-> int Np

Number of predictor coefficients

Author / revision

See Also