Hilbert
Hilbert
MODIFIED API.
Computes an analytic signal using the Hilbert transform.
Syntax
IppStatus ippsHilbert_32f32fc(const Ipp32f*
pSrc
, Ipp32fc*
pDst
, IppsHilbertSpec*
pSpec
, Ipp8u*
pBuffer
);
IppStatus ippsHilbert_64f64fc(const Ipp64f*
pSrc
, Ipp64fc*
pDst
, IppsHilbertSpec*
pSpec
, Ipp8u*
pBuffer
);
Include Files
ipps.h
Domain Dependencies
Headers:
ippcore.h
,
ippvm.h
Libraries:
ippcore.lib
,
ippvm.lib
Parameters
- pSpec
- Pointer to the Hilbert specification structure.
- pSrc
- Pointer to the vector containing original real data.
- pDst
- Pointer to the output array containing complex data.
- pBuffer
- Pointer to the work buffer.
Description
The API of this function has been modified in Intel IPP 9.0 release.
The
ippsHilbert
function computes a complex analytic signal
pDst
, which contains the original real signal
pSrc
as its real part and computed Hilbert transform as its imaginary part. The Hilbert transform is performed according to the
pSpec
specification parameters: the number of samples
len
, and the specific code
hint
. The input data is zero-padded or truncated to the size of
len
as appropriate.
Before using this function, you need to compute the size of the work buffer and specification structure using the
HilbertGetSize
function and initialize the structure using
HilbertInit
.
Return Values
- ippStsNoErr
- Indicates no error.
- ippStsNullPtrErr
- Indicates an error when one of the specified pointers isNULL.
- ippStsContextMatchErr
- Indicates an error when the specification identifierpSpecis incorrect.
Example
The example below shows how to initialize the specification structure and use the function
ippsHilbert_32f32fc
.IppStatus hilbert( ) { Ipp32f x[10]; Ipp32fc y[10]; int n; IppStatus status; IppsHilbertSpec* pSpec; Ipp8u* pBuffer; int sizeSpec, sizeBuf; status = ippsHilbertGetSize_32f32fc(10, ippAlgHintNone, &sizeSpec, &sizeBuf); pSpec = (IppsHilbertSpec*)ippMalloc(sizeSpec); pBuffer = (Ipp8u*)ippMalloc(sizeBuf); status = ippsHilbertInit_32f32fc(10, ippAlgHintNone, pSpec, pBuffer); for (n = 0; n < 10; n ++) { x[n] = (Ipp32f)cos(IPP_2PI * n * 2 / 9); } status = ippsHilbert_32f32fc(x, y, pSpec, pBuffer); ippsMagnitude_32fc((Ipp32fc*)y, x, 5); ippFree(pSpec); ippFree(pBuffer); printf_32f("hilbert magn =", x, 5, status); return status; }
Output:
hilbert magn = 1.0944 1.1214 1.0413 0.9707 0.9839 Matlab* Analog: >> n=0:9; x=cos(2*pi*n*2/9); y=abs(hilbert(x)); y(1:5)