Preemphasize

Computes pre-emphasis of a speech signal.

Syntax

IppStatus ippsPreemphasize_AMRWB_16s_ISfs (Ipp16s gamma, Ipp16s* pSrcDst, int len, int scaleFactor, Ipp16s* pMem);

Parameters

gamma	Filter coefficient.
pSrcDst	Pointer to the input/output vector.
scaleFactor	Scale factor for the result.
len	Length of the input/output vector.
pMem	Pointer to the filter memory of length 1.

Description

This function is declared in ippsc.h file. It computes pre-emphasis of the input speech according to the difference signal pre-emphasis equation:

H(z) = 1 - γ*z^-1

The memory value pMem[0] is updated by pSrcDst[n-1]. For proper use of this function in AMR WB codec, the memory value must be initialized to zero in the user program.

Return Values

ippStsNoErr	Indicates no error.
ippStsNullPtrErr	Indicates an error when the pSrcDst or pMem pointer is NULL.
ippStsSizeErr	Indicates an error when len is less than or equal to zero.
ippStsScaleRangeErr	Indicates an error when scaleFactor < 0 or scaleFactor > 15.