Implements an inverse LP filter and obtains the residual signal.
Syntax
IppStatus ippsResidualFilter_G729_16s(const Ipp16s* pSrcSpch, const Ipp16s* pSrcLPC, Ipp16s* pDstResidual);
IppStatus ippsResidualFilter_G729E_16s(const Ipp16s* pCoeffs, int order, const Ipp16s* pSrc, Ipp16s* pDst, int len);
Parameters
pSrcSpch |
Pointer to the input speech signal. Elements pSrcSpch[0...39] are the present speech signals, whereas pSrcSpch[-10... -1] are the history to be used. |
pSrcLPC |
Pointer to the LP coefficients vector [11], in Q12. |
pDstResidual |
Pointer to the LP residual. |
pCoeffs |
Pointer to the vector [order +1] of filter coefficients. |
order |
The filter order. |
pSrc |
Pointer to the source vector [len]. Values pSrc [-order,..,-1] must also be supplied. |
pDst |
Pointer to the output filtered residual vector [len]. |
len |
Length of the source and destination vectors. |
Description
The functions ippsResidualFilter_G729 and ippsResidualFilter_G729E are declared in the ippsc.h file.
ippsResidualFilter_G729. This function filters the input speech signal through an inverse LP filter and gets the residual signal as:
n = 0, 1,..., 39 .
ippsResidualFilter_G729E. This function implements the same operation as the previous function, but accepts the variable filter order.
Return Values
ippStsNoErr |
Indicates no error. |
ippStsNullPtrErr |
Indicates an error when one of the specified pointers is NULL. |
ippStsSizeErr |
Indicates an error when order is less than or equal to 0, or when len is less than or equal to 0 and valLPCOrder > len. |