Evaluates variance and mean of 8X8 block.
Syntax
IppStatus ippiVarMean8x8_8u32s_C1R(const Ipp8u* pSrc, Ipp32s srcStep, Ipp32s* pVar, Ipp32s* pMean);
IppStatus ippiVarMean8x8_16s32s_C1R(const Ipp16s* pSrc, Ipp32s srcStep, Ipp32s* pVar, Ipp32s* pMean);
Parameters
pSrc |
Pointer to the input block 8x8. |
srcStep |
Input block step. |
pVar |
Pointer to the variance. |
pMean |
Pointer to the mean value. |
Description
This function is declared in the ippvc.h header file. The function evaluates the mean and variance of an 8x8 block of unsigned char values (ippiVarMean8x8_8u32s_C1R) or short integer values (ippiVarMean8x8_16s32s_C1R).
Mean is evaluated by the following formula:
The actual value of the M is sum rather than mean yet this designation is preserved for convenience.
Variance is evaluated by the following formula:
This function is used in the MPEG-2 encoder included into Intel IPP Samples. See introduction to this section.
Return Values
ippStsNoErr |
Indicates no error. |
ippStsNullPtrErr |
Indicates an error when at least one input pointer is NULL. |