PostFilter_GSMAMR

Filters the synthesized speech.

Syntax

IppStatus ippsPostFilter_GSMAMR_16s(const Ipp16s* pSrcQLpc, const Ipp16s* pSrcSpch, Ipp16s* pValResultPrevResidual, Ipp16s* pValResultPrevScalingGain, Ipp16s* pSrcDstFormantFIRState, Ipp16s* pSrcDstFormantIIRState, Ipp16s* pDstFltSpch, IppSpchBitRate mode);

Parameters

pSrcQLpc	Pointer to the reconstructed LP coefficients, in the length of 44, in Q3.12.
pSrcSpch	Pointer to the start position of the input speech signal for the current frame, in the length of 160, in Q15.0.
pValResultPrevResidual	On entry, pointer to the last output of the FIR filter of the format filter for previous subframe, in Q15.0. It is the input of the tilt compensation filter. On exit, points to the last output of the FIR filter of the formant filter for this subframe (in Q15.0) and is the output of the tilt compensation filter. This value is initialized to 0 and can only be updated by this function.
pValResultPrevScalingGain	Pointer to the scaling factor b of the last signal for the previous subframe, in Q3.12. On output, points to the scaling factor b of the last signal for this subframe, in Q3.12.
pSrcDstFormantFIRState	Pointer to the state of the FIR part of the formant filter, in the length of 10, in Q15.0. On output, points to the updated state of the FIR part of the formant filter, in the length of 10, in Q15.0.
pSrcDstFormantIIRState	Pointer to the state of the IIR part of the formant filter, in the length of 10, in Q15.0. On output, points to the updated state of the IIR part of the formant filter, in the length of 10, in Q15.0.
pDstFltSpch	Pointer to the filtered speech, in the length of 160, in Q15.0.
mode	Bit rate specifier. Values between IPP_SPCHBR_4750 and IPP_SPCHBR_12200 are valid.

Description

The function ippsPostFilter_GSMAMR is declared in ippsc.h file. This function filters the synthesized speech to enhance reconstruction quality.

Return Values

ippStsNoErr	Indicates no error.
IppStsNullPtrErr	Indicates an error when one of the specified pointers is NULL.
ippStsRangeErr	Indicates an error when the input variable mode is out of range.