5.2.2 Levinson‑Durbin algorithm (all modes)

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The modified auto‑correlations and are used to obtain the direct form LP filter coefficients by solving the set of equations.

(9)

The set of equations in (9) is solved using the Levinson‑Durbin algorithm. This algorithm uses the following recursion:

The final solution is given as .

The LP filter coefficients are converted to the line spectral pair (LSP) representation for quantization and interpolation purposes. The conversions to the LSP domain and back to the LP filter coefficient domain are described in the next clause.