Convert linear prediction coefficients or reflection coefficients to autocorrelation coefficients

Estimation / Linear Prediction

`dsplp`

The LPC/RC to Autocorrelation block either converts linear prediction
coefficients (LPCs) to autocorrelation coefficients (ACs) or reflection
coefficients (RCs) to autocorrelation coefficients (ACs). Set the **Type
of conversion** parameter to `LPC to autocorrelation`

or ```
RC
to autocorrelation
```

to select the domain from which you
want to convert your coefficients. The A port corresponds to LPC coefficients,
and the K port corresponds to the RC coefficients.

The block input can be an *N*-by-*M* matrix
or an unoriented vector. Each column of the matrix is treated as
a channel. When the input is an unoriented vector, the input is treated
as one channel.

Use the **Specify P** parameter to set the
value of the prediction error power. You can set this parameter to
1 by selecting `Assume P=1`

. When you select ```
Via
input port
```

, a P port appears on the block. You can use
this port to input the value of the actual, non-unity prediction error
power for each channel. The length of this vector must equal the number
of channels in the input.

The **If first input value is not 1** parameter
specifies the behavior of the block when the first coefficient of
the LPC coefficient vector is not 1. The following options are available:

`Replace it with 1`

— The block changes the first value of the coefficient vector to 1. The rest of the coefficient values are unchanged.`Normalize`

— The block divides the entire vector of coefficients by the first coefficient so that the first coefficient of the LPC coefficient vector is 1.`Normalize and Warn`

— The block divides the entire vector of coefficients by the first coefficient so that the first coefficient of the LPC coefficient vector is 1. The block displays a warning message telling you that your vector of coefficients has been normalized.`Error`

— The block displays an error telling you that the first coefficient of the LPC coefficient vector is not 1.

**Type of conversion**From the list select

`LPC to autocorrelation`

or`RC to autocorrelation`

to specify the domain from which you want to convert your coefficients.**Specify P**From the list select

`Assume P=1`

or`Via input port`

to specify the value of prediction error power.**If first input value is not 1**Select what you would like the block to do when the first coefficient of the LPC coefficient vector is not 1. You can choose

`Replace it with 1`

,`Normalize`

,`Normalize and Warn`

, and`Error`

.

Orfanidis, S.J. *Optimum Signal Processing*.
New York, McGraw-Hill, 1988.

Makhoul, J. *Linear Prediction: A tutorial review*.
Proc. IEEE. 63, 63, 56 (1975).

Markel, J.D. and A. H. Gray, Jr., *Linear Prediction
of Speech*. New York, Springer-Verlag, 1976.

Double-precision floating point

Single-precision floating point

Levinson-Durbin | DSP System Toolbox |

LPC to LSF/LSP Conversion | DSP System Toolbox |

LSF/LSP to LPC Conversion | DSP System Toolbox |

LPC to/from RC | DSP System Toolbox |

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