GainQuant_AMRWBE

Quantizes the adaptive codebook gains.

Syntax

IppStatus ippsGainQuant_AMRWBE_16s(Ipp16s* pSrcAdptTarget, const Ipp16s * pSrcFltAdptVector, int valFormat, const Ipp16s* pSrcFixedVector, const Ipp16s* pSrcFltFixedVector, int lenSrc, const Ipp16s* pSrcCorr, Ipp16s meanEnergy, Ipp16s* pSrcDstPitchGain, Ipp16s* pDstCorrFactor, Ipp32s* pDstCodeGain, Ipp16s* pDstQGainIndex);

Parameters

pSrcAdptTarget	Pointer to the input target vector x(n).
pSrcFltAdptVector	Pointer to the input filtered adaptive codebook vector y(n).
valFormat	Format of the pSrcAdptTarget and pSrcFltAdptVector vectors.
pSrcFixedVector	Pointer to the input pre-filtered codebook contribution c(n).
pSrcFltFixedVector	Pointer to the input filtered codebook vector z(n).
lenSrc	Length of the input vectors (n).
pSrcCorr	Pointer to the vector of correlations between the pSrcAdptTarget, pSrcFltAdptVector, pSrcFltFixedVector vectors.
meanEnergy	Average energy in the whole frame.
pSrcDstPitchGain	Pointer to the input/output pitch gain.
pDstCorrFactor	Pointer to the correction factor.
pDstCodeGain	Pointer to the output code gain.
pDstQGainIndex	Pointer to the output codebook indexes found.

Description

The function ippsGainQuant_AMRWBE is declared in ippsc.h file. This function quantizes the adaptive codebook gain (pitch gain) and the fixed (algebraic) codebook gain using the same 7-bit codebook that is used in the function ippsGainQuant_AMRWB for modes from 12.6 to 23.8 kbit/s. However, instead of using "moving average" prediction to obtain the predicted gain g_C, it is found directly by quantizing the average energy meanEnergy in the whole frame.

Return Values

ippStsNoErr	Indicates no error.
ippStsNullPtrErr	Indicates an error when one of the specified pointer is NULL.
ippStsSizeErr	Indicates an error when lenSrc is less than or equal to zero.