mlib_SignalLPC2Cepstral_S1mediaLib Library Fmlib_SignalLPC2Cepstral_S16(3MLIB)NAMEmlib_SignalLPC2Cepstral_S16 - convert linear prediction coefficients to
cepstral coefficients
SYNOPSIS
cc [ flag... ] file... -lmlib [ library... ]
#include <mlib.h>
mlib_status mlib_SignalLPC2Cepstral_S16(mlib_s16 *cepst,
mlib_s32 cscale, const mlib_s16 *lpc, mlib_s32 lscale,
mlib_s16 gain, mlib_s32 gscale, mlib_s32 length,
mlib_s32 order);
DESCRIPTION
The mlib_SignalLPC2Cepstral_S16() function converts linear prediction
coefficients to cepstral coefficients. The user supplied scaling fac‐
tor, cscale, will be used and the output will be saturated if neces‐
sary.
The cepstral coefficients are the coefficients of the Fourier transform
representation of the log magnitude spectrum.
The LPC cepstral coefficients can be derived recursively from the LPC
coefficients as following.
c(0) = log(G)
m-1 k
c(m) = a(m) + SUM --- * c(k) * a(m-k), 1 ≤ m ≤ M
k=1 m
m-1 k
c(m) = SUM --- * c(k) * a(m-k), m > M
k=1 m
See Fundamentals of Speech Recognition by Lawrence Rabiner and Biing-
Hwang Juang, Prentice Hall, 1993.
PARAMETERS
The function takes the following arguments:
cepst The cepstral coefficients.
cscale The scaling factor of the cepstral coefficients, where
actual_data = output_data * 2**(-scaling_factor).
lpc The linear prediction coefficients.
lscale The scaling factor of the linear prediction coefficients,
where actual_data = input_data * 2**(-scaling_factor).
gain The gain of the LPC model.
gscale The scaling factor of the gain of the LPC model, where
actual_data = input_data * 2**(-scaling_factor).
length The length of the cepstral 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 ALSOmlib_SignalLPC2Cepstral_S16(3MLIB), mlib_SignalLPC2Cep‐
stral_S16_Adp(3MLIB), mlib_SignalLPC2Cepstral_F32(3MLIB), attributes(5)SunOS 5.10 2 Mar 2007mlib_SignalLPC2Cepstral_S16(3MLIB)
