mlib_SignalLPC2LSP_F32(3MLIB)				    mediaLib Library Functions				     mlib_SignalLPC2LSP_F32(3MLIB)

NAME

       mlib_SignalLPC2LSP_F32 - convert linear prediction coefficients to line spectral pair coefficients

SYNOPSIS

       cc [ flag... ] file... -lmlib [ library... ]
       #include <mlib.h>

       mlib_status mlib_SignalLPC2LSP_F32(mlib_f32 *lsp, const mlib_f32 *lpc,
	    mlib_s32 order);

DESCRIPTION

       The mlib_SignalLPC2LSP_F32() function converts linear prediction coefficients to line spectral pair coefficients.

       The line spectral pair (LPS) coefficients are defined as the roots of the following two polynomials:

			     -(M+1)	-1
	      P(z) = A(z) + z	   * A(z  )

			     -(M+1)	-1
	      Q(z) = A(z) - z	   * A(z  )

       where A(z) is the inverse filter

			 M	    -i
	      A(z) = 1- SUM a(i) * z
			i=1

       Note  that  since P(z) is symmetric and Q(z) is antisymmetric all roots of these polynomials are on the unit circle and they alternate each
       other. P(z) has a root at z = -1 (w = PI) and Q(z) has a root at z = 1 (w = 0).

       The line spectral frequency (LPF) are the angular frequency of the line spectral pair (LPS) coefficients.

	      q = cos(w)

       where q is the LPS and w is the LPF.

       See Fundamentals of Speech Recognition by Lawrence Rabiner and Biing-Hwang Juang, Prentice Hall, 1993.

PARAMETERS

       The function takes the following arguments:

       lsp	The line spectral pair coefficients.

       lpc	The linear prediction coefficients.

       order	The order of the linear prediction filter.

RETURN VALUES

       The function returns MLIB_SUCCESS if successful. Otherwise it returns MLIB_FAILURE.

ATTRIBUTES

       See attributes(5) for descriptions of the following attributes:

       +-----------------------------+-----------------------------+
       |      ATTRIBUTE TYPE	     |	    ATTRIBUTE VALUE	   |
       +-----------------------------+-----------------------------+
       |Interface Stability	     |Committed 		   |
       +-----------------------------+-----------------------------+
       |MT-Level		     |MT-Safe			   |
       +-----------------------------+-----------------------------+

SEE ALSO

       mlib_SignalLSP2LPC_F32(3MLIB), attributes(5)

SunOS 5.11							    2 Mar 2007					     mlib_SignalLPC2LSP_F32(3MLIB)