Buffers the ISF coefficients and previous logarithm energy coefficients.
Syntax
IppStatus ippsDecDTXBuffer_AMRWB_16s(const Ipp16s* pSrcSpch, const Ipp16s* pSrcIsf, Ipp16s* pUpdateIndex, Ipp16s* pSrcDstIsfBuffer, Ipp16s* pSrcDstLogEnergyBuffer);
Parameters
pSrcSpch |
Pointer to the input speech signal of length 256 . |
pSrcIsp |
Pointer to the ISP for this frame, of length 16. |
pUpdateIndex |
Holds the previous memory update index. On output, it contains the current memory update index. Circularly increased between 0 and 7. |
pSrcDstIspBuffer |
Pointer to the ISP coefficients of eight previous frames,of length 128. On output, points to the ISP coefficients of eight most recent frames (including the current frame). |
pSrcDstLogEnergyBuffer |
Pointer to the logarithm energy coefficients of eight previous frames, of length 8. On output, points to the logarithm energy coefficients of eight most recent frames (including the current frame). |
Description
The function ippsDecDTXBuffer_AMRWB is declared in ippsc.h file. This function buffers the ISF coefficients and previous logarithm energy coefficients. The buffered ISF coefficients and energy coefficients are used by the SID frame to extract necessary parameters. The memory update index indicates which part of the buffer will be updated and thus saves the cost of some memory copy operation. The logarithm energy is computed as follows:
The function ippsDecDTXBuffer_AMRWB behaves similarly to the ippsDecDTXBuffer_GSMAMR function of the GSM-AMR codec.
Return Values
ippStsNoErr |
Indicates no error. |
ippStsNullPtrErr |
Indicates an error when one of the specified pointers is NULL. |