Package: dsp
Convert linear prediction coefficients to line spectral frequencies
The LPCToLSF
object converts linear prediction
coefficients to line spectral frequencies.
To convert LPC to LSF:
Define and set up your LPC to LSF converter. See Construction.
Call step
to convert LPC according to the properties
of dsp.LPCToLSF
. The behavior of step
is
specific to each object in the toolbox.
Note:
Starting in R2016b, instead of using the 
H = dsp.LPCToLSF
returns
a System object, H
, that converts linear prediction
coefficients (LPCs) to line spectral frequencies (LSFs).
H = dsp.LPCToLSF('
returns
an PropertyName
',PropertyValue
,...)LPC
to LSF
System object, H
,
with each specified property set to the specified value.

Number of coarse subintervals used for finding roots (LSP values) Specify the number of coarse subintervals, 

Value of bisection refinement used for finding roots Specify the root bisection refinement value, $$\frac{1}{(n\cdot {2}^{k})}$$ of
the actual LSP value. Here n is the value of
the 

Produces output with validity status of LSF output Set this property to 

Enable overwriting invalid output with previous output Specify the action that the System object should take for
invalid LSF outputs. When you set this property to 

Source of values for first output when output is invalid Specify the source of values for the first output when the output
is invalid as 

Value of the first output Specify a numeric vector of LSF values for overwriting an invalid
first output. The length of this vector must be one less than the
length of the input LPC vector. For multichannel inputs, you can set
this property to a matrix with the same number of channels as the
input, or one vector that is applied to every channel. The default
is an empty vector. This property applies when you set the 

Action to take when first LPC coefficient is not Specify the action the object takes when the first coefficient
of each channel of the LPC input is not 
clone  Create LPC To LSF object with same property values 
getNumInputs  Number of expected inputs to step method 
getNumOutputs  Number of outputs of step method 
isLocked  Locked status for input attributes and nontunable properties 
release  Allow property value and input characteristics changes 
reset  Reset values for overwriting invalid outputs to their initial values 
step  Convert LPC coefficients to line spectral frequencies 
This object implements the algorithm, inputs, and outputs described on the LPC to LSF/LSP Conversion block reference page. The object properties correspond to the block parameters, except:
There is no object property that corresponds to the Output block parameter. The object only supports LSF outputs in the range (0,$$\prod $$) 