Performs noise reduction filtering
Syntax
IppStatus ippsFilterNoise_RTA_32f_I(Ipp32f pSrcDst[160], IppsFilterNoiseState_RTA_32f* pNRStateMem);
IppStatus ippsFilterNoise_RTA_32f(const Ipp32f pSrc[160], Ipp32f pDst[160], IppsFilterNoiseState_RTA_32f* pNRStateMem);
IppStatus ippsFilterNoise_EC_32f_I(const Ipp32f pSrcDst[16], IppsNrMode filterMode, IppsFilterNoiseState_EC_32f* pNRStateMem);
IppStatus ippsFilterNoise_EC_32f(const Ipp32f pSrc[16], Ipp32f pDst[16], IppsNrMode filterMode, IppsFilterNoiseState_EC_32f* pNRStateMem);
Parameters
pSrc |
Pointer to the input vector. |
pDst |
Pointer to the output vector. |
pSrcDst |
Pointer to the input and output vector |
filterMode |
Specifies how the filter state structure is updated: ippsNrNon - no update, ippsNrUpdate - signal statistics update, ippsNrUpdateAll - signal and noise statistics update. |
pNRStateMem |
Pointer to the filter state structure. |
Description
The functions ippsFilterNoise are declared in the ippsc.h file. These functions perform noise reduction filtering of the noisy speech signal. The filter state structure must be initialized beforehand using the respective ippsFilterNoiseInit function. The functions ippsFilterNoise use the predefined levels of the noise attenuation. Their default value set during the state structure's initialization can be changed using the function ippsFilterNoiseLevel. The parameter filterMode specified how the filter state structure is updated.
Code Examples show how the function ippsFilterNoise can be used.
Note
The higher noise attenuation level is set, the more undesirable distortions of the speech signal can occur.
Note
When the speech signal has low signal-to-noise ratio (SNR), some degradation may be observed after the noise reduction.
Return Values
ippStsNoErr |
Indicates no error. |
ippStsNullPtrErr |
Indicates an error when one of the specified pointers is NULL. |
IppStsRangeErr |
Indicates an error when filterMode has an invalid value. |