Directly filters a single sample through a FIR filter.
Syntax
Case 1: Not-in-place operation on integer sample
IppStatus ippsFIROne_Direct_16s_Sfs(Ipp16s src, Ipp16s* pDstVal, const Ipp16s* pTapsQ15, int tapsLen, Ipp16s* pDlyLine, int* pDlyLineIndex, int scaleFactor);
IppStatus ippsFIROne32f_Direct_16s_Sfs(Ipp16s src, Ipp16s* pDstVal, const Ipp32f* pTaps, int tapsLen, Ipp16s* pDlyLine, int* pDlyLineIndex, int scaleFactor);
IppStatus ippsFIROne64f_Direct_16s_Sfs(Ipp16s src, Ipp16s* pDstVal, const Ipp64f* pTaps, int tapsLen, Ipp16s* pDlyLine, int* pDlyLineIndex, int scaleFactor);
IppStatus ippsFIROne64f_Direct_32s_Sfs(Ipp32s src, Ipp32s* pDstVal, const Ipp64f* pTaps, int tapsLen, Ipp32s* pDlyLine, int* pDlyLineIndex, int scaleFactor);
IppStatus ippsFIROne32fc_Direct_16sc_Sfs(Ipp16sc src, Ipp16sc* pDstVal, const Ipp32fc* pTaps, int tapsLen, Ipp16sc* pDlyLine, int* pDlyLineIndex, int scaleFactor);
IppStatus ippsFIROne64fc_Direct_16sc_Sfs(Ipp16sc src, Ipp16sc* pDstVal, const Ipp64fc* pTaps, int tapsLen, Ipp16sc* pDlyLine, int* pDlyLineIndex, int scaleFactor);
IppStatus ippsFIROne64fc_Direct_32sc_Sfs(Ipp32sc src, Ipp32sc* pDstVal, const Ipp64fc* pTaps, int tapsLen, Ipp32sc* pDlyLine, int* pDlyLineIndex, int scaleFactor);
IppStatus ippsFIROne32s_Direct_16s_Sfs(Ipp16s src, Ipp16s* pDstVal, const Ipp32s* pTaps, int tapsLen, int tapsFactor, Ipp16s* pDlyLine, int* pDlyLineIndex, int scaleFactor);
IppStatus ippsFIROne32sc_Direct_16sc_Sfs(Ipp16sc src, Ipp16sc* pDstVal, const Ipp32sc* pTaps, int tapsLen, int tapsFactor, Ipp16sc* pDlyLine, int* pDlyLineIndex, int scaleFactor);
Case 2: Not-in-place operation on floating point sample
IppStatus ippsFIROne_Direct_32f(Ipp32f src, Ipp32f* pDstVal, const Ipp32f* pTaps, int tapsLen, Ipp32f* pDlyLine, int* pDlyLineIndex);
IppStatus ippsFIROne_Direct_64f(Ipp64f src, Ipp64f* pDstVal, const Ipp64f* pTaps, int tapsLen, Ipp64f* pDlyLine, int* pDlyLineIndex);
IppStatus ippsFIROne_Direct_32fc(Ipp32fc src, Ipp32fc* pDstVal, const Ipp32fc* pTaps, int tapsLen, Ipp32fc* pDlyLine, int* pDlyLineIndex);
IppStatus ippsFIROne_Direct_64fc(Ipp64fc src, Ipp64fc* pDstVal, const Ipp64fc* pTaps, int tapsLen, Ipp64fc* pDlyLine, int* pDlyLineIndex);
IppStatus ippsFIROne64f_Direct_32f(Ipp32f src, Ipp32f* pDstVal, const Ipp64f* pTaps, int tapsLen, Ipp32f* pDlyLine, int* pDlyLineIndex);
IppStatus ippsFIROne64fc_Direct_32fc(Ipp32fc src, Ipp32fc* pDstVal, const Ipp64fc* pTaps, int tapsLen, Ipp32fc* pDlyLine, int* pDlyLineIndex);
Case 3: In-place operation on integer sample
IppStatus ippsFIROne_Direct_16s_ISfs(Ipp16s* pSrcDstVal, const Ipp16s* pTaps, int tapsLen, Ipp16s* pDlyLine, int* pDlyLineIndex, int scaleFactor);
IppStatus ippsFIROne32f_Direct_16s_ISfs(Ipp16s* pSrcDstVal, const Ipp32f* pTaps, int tapsLen, Ipp16s* pDlyLine, int* pDlyLineIndex, int scaleFactor);
IppStatus ippsFIROne64f_Direct_16s_ISfs(Ipp16s* pSrcDstVal, const Ipp64f* pTaps, int tapsLen, Ipp16s* pDlyLine, int* pDlyLineIndex, int scaleFactor);
IppStatus ippsFIROne64f_Direct_32s_ISfs(Ipp32s* pSrcDstVal, const Ipp64f* pTaps, int tapsLen, Ipp32s* pDlyLine, int* pDlyLineIndex, int scaleFactor);
IppStatus ippsFIROne32fc_Direct_16sc_ISfs(Ipp16sc* pSrcDstVal, const Ipp32fc* pTaps, int tapsLen, Ipp16sc* pDlyLine, int* pDlyLineIndex, int scaleFactor);
IppStatus ippsFIROne64fc_Direct_16sc_ISfs(Ipp16sc* pSrcDstVal, const Ipp64fc* pTaps, int tapsLen, Ipp16sc* pDlyLine, int* pDlyLineIndex, int scaleFactor);
IppStatus ippsFIROne64fc_Direct_32sc_ISfs(Ipp32sc* pSrcDstVal, const Ipp64fc* pTaps, int tapsLen, Ipp32sc* pDlyLine, int* pDlyLineIndex, int scaleFactor);
IppStatus ippsFIROne32s_Direct_16s_ISfs(Ipp16s* pSrcDstVal, const Ipp32s* pTaps, int tapsLen, int tapsFactor, Ipp16s* pDlyLine, int* pDlyLineIndex, int scaleFactor);
IppStatus ippsFIROne32sc_Direct_16sc_ISfs(Ipp16sc* pSrcDstVal, const Ipp32sc* pTaps, int tapsLen, int tapsFactor, Ipp16sc* pDlyLine, int* pDlyLineIndex, int scaleFactor);
Case 4: In-place operation on floating point sample
IppStatus ippsFIROne_Direct_32f_I(Ipp32f* pSrcDstVal, const Ipp32f* pTaps, int tapsLen, Ipp32f* pDlyLine, int* pDlyLineIndex);
IppStatus ippsFIROne_Direct_64f_I(Ipp64f* pSrcDstVal, const Ipp64f* pTaps, int tapsLen, Ipp64f* pDlyLine, int* pDlyLineIndex);
IppStatus ippsFIROne_Direct_32fc_I(Ipp32fc* pSrcDstVal, const Ipp32fc* pTaps, int tapsLen, Ipp32fc* pDlyLine, int* pDlyLineIndex);
IppStatus ippsFIROne_Direct_64fc_I(Ipp64fc* pSrcDstVal, const Ipp64fc* pTaps, int tapsLen, Ipp64fc* pDlyLine, int* pDlyLineIndex);
IppStatus ippsFIROne64f_Direct_32f_I(Ipp32f* pSrcDstVal, const Ipp64f* pTaps, int tapsLen, Ipp32f* pDlyLine, int* pDlyLineIndex);
IppStatus ippsFIROne64fc_Direct_32fc_I(Ipp32fc* pSrcDstVal, const Ipp64fc* pTaps, int tapsLen, Ipp32fc* pDlyLine, int* pDlyLineIndex);
Parameters
src |
Input sample. |
pDstVal |
Pointer to the output sample. |
pSrcDstVal |
Pointer to the input and output sample for in-place operation. |
pTaps |
Pointer to the array containing the tap values. The number of elements in the array is tapsLen. |
pTapsQ15 |
Pointer to the array containing the tap values, represented in Q0.15 format. The number of elements in the array is tapsLen. |
tapsLen |
Number of elements in the array containing the tap values. |
tapsFactor |
Scale factor for the integer taps. |
pDlyLine |
Pointer to the array containing the delay line values. The number of elements in the array is 2*tapsLen. Note that the delay line length is different than that for FIR filters using state structure. |
pDlyLineIndex |
Pointer to the current delay line index. |
scaleFactor |
Scale factor, refer to Integer Scaling. |
Description
The function ippsFIROne_Direct is declared in the ipps.h file. This function directly filters a single sample src or pSrcDstVal through a single-rate filter and stores the result in pDstVal or pSrcDstVal. The values of filter coefficients (taps) are specified in the tapsLen-length array pTaps. To scale integer taps, the tapsFactor value is used. The set of tapsLen input samples is copied twice to the 2*tapsLen-length array pDlyLine. Double length of the delay line in direct FIR filters is used to improve filter performance by decreasing the number of sample copyings. The current delay line index is specified in the pDlyLineIndex. The output of the integer sample is scaled according to scaleFactor and can be saturated. In the following definition of the FIR filter, the sample to be filtered is denoted x(n) and the taps are denoted h(i).
The return value y(n) is defined by the formula for a single-rate filter:
Return Values
ippStsNoErr |
Indicates no error. |
ippStsNullPtrErr |
Indicates an error when one of the specified pointers is NULL. |
ippStsFIRLenErr |
Indicates an error when tapsLen is less than or equal to 0. |