Buffers the ISP coefficients and previous logarithm energy coefficients.
Syntax
IppStatus ippsEncDTXBuffer_AMRWB_16s(const Ipp16s* pSrcSpch, const Ipp16s* pSrcIsp, Ipp16s* pUpdateIndex, Ipp16s* pSrcDstIspBuffer, Ipp16s* pSrcDstLogEnergyBuffer, IppSpchBitRate mode);
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. It is circularly increased between 0 and 7. |
pSrcDstIspBuffer |
Pointer to the ISP coefficients of the eight most recent 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 the eight most recent frames, of length 8. On output, points to the logarithm energy coefficients of eight most recent frames (including the current frame). |
mode |
Bit rate specifier. Values between IPP_SPCHBR_6600 and IPP_SPCHBR_23850 are valid. |
Description
The function ippsEncDTXBuffer_AMRWB is declared in ippsc.h file. This function buffers the ISP coefficients and previous logarithm energy coefficients. The buffered ISP coefficients and energy coefficients are used for 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:
After computation, the energy is adjusted according to the current encoder mode.
The function ippsEncDTXBuffer_AMRWB behaves similarly to the ippsEncDTXBuffer_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. |
|
ippStsRangeErr |
Indicates an error when mode is not a valid element of the enumerated type IppSpchBitRate. |