LSPQuant_GSMAMR

Quantizes the LSP coefficient vector.

Syntax

IppStatus ippsLSPQuant_GSMAMR_16s(const Ipp16s* pSrcLsp, Ipp16s* pSrcDstPrevQLsfResidual, Ipp16s* pDstQLsp, Ipp16s* pDstQLspIndex, IppSpchBitRate mode);

Parameters

pSrcLsp	Pointer to the unquantized 20-element LSP vector, represented using Q0.15. For 12.2 kbps frames, the first LSP set is contained in vector elements 0 ~ 9, and the second LSP set is contained in vector elements 10 ~ 19. For all other bit rates, only elements 0 to 9 are valid and used for the quantization.
pSrcDstPrevQLsfResidual	Pointer to the ten-element quantized LSF residual from the previous frame, represented using Q0.15. On output, points to the ten-element quantized LSF residual for the current frame, represented using Q0.15.
pDstQLsp	Pointer to the 20-element quantized LSP vector, represented using Q0.15. For 12.2 kbps frames, elements 0 to 9 contain the first quantized LSP set, and elements 10 to 19 contain the second quantized LSP set. For all other bit rates there is only one LSP set contained in elements 0 to 9.
pDstQLspIndex	Pointer to the five-element vector of quantized LSP indices. For 12.2Kbps frames, all five elements contain valid data; for all other bit rates, only the first three elements contain valid indices (see the following discussion of SMQ and SVQ for the various modes).
mode	Bit rate specifier. The enumerated values of IPP_SPCHBR_4750 to IPP_SPCHBR_12200 are valid.

Description

The function ippsLSPQuant_GSMAMR is declared in ippsc.h file. This function quantizes the LSP coefficient vector, then obtains quantized LSP codebook indices.

Return Values

ippStsNoErr	Indicates no error.
IppStsNullPtrErr	Indicates an error when one of the specified pointers is NULL.
ippStsRangeErr	Indicates an error when mode is not a valid element of the enumerated type IppSpchBitRate.