LtpUpdate

Performs required buffer update in the Long Term Reconstruct (LTP) loop.

Syntax

IppStatus ippsLtpUpdate_AAC_32s(Ipp32s* pSpecVal, Ipp32s* pLtpSaveBuf, int winSequence, int winShape, int preWinShape, Ipp32s* pWorkBuf);

Parameters

pSpecVal	Pointer to spectral value after TNS decoder in LTP loop.
pLtpSaveBuf	Pointer to save buffer for LTP. Buffer length must be 3*frameLength. The value is saved for the next frame.
winSequence	Window type: 0 stands for long, 1 stands for long start, 2 stands for short, 3 stands for long stop.
winShape	KBD or SIN window shape.
preWinShape	Previous window shape.
pWorkBuf	Work buffer for LTP update, length of pWorkBuf should be at least 2048*3 = 6144 words.

Description

This function is declared in the ippac.h file. The function performs required buffer update in the Long Term Reconstruct (LTP) loop. This operation includes IMDCT and updating the save buffer.

Return Values

ippStsNoErr	Indicates no error.
ippStsNullPtrErr	Indicates an error when at least one of the specified pointers is NULL.
ippStsAacWinSeqErr	Indicates an error when winSequence exceeds [0,3].
ippStsAacWinShapeErr	Indicates an error when winShape or preWinShape exceeds [0,1].