Computes the inverse discrete cosine transform (DCT) of a signal.
Syntax
Ippstatus ippsDCTInv_G722_16s (const Ipp16s* pSrc, Ipp16s* pDst);
IppStatus ippsDCTInv_G7221_16s (const Ipp16s* pSrc, Ipp16s* pDst, int len);
Parameters
pSrc |
Pointer to the source vector. |
pDst |
Pointer to the destination vector. |
len |
Number of elements on the source and destination vectors, possible values: 320, 640. |
Description
The functions ippsDCTInv are declared in ippsc.h file. The function ippsDCTInv_G722 computes the inverse discrete cosine transform (DCT) of the fixed length [320]. The function ippsDCTInv_G7221 computes the inverse DCT of the length len. The calculation is performed according to the following formula:
Return Values
ippStsNoErr |
Indicates no error. |
ippStsNullPtrErr |
Indicates an error when one of the specified pointer is NULL. |
ippStsSizeErr |
Indicates an error when the len has an illegal value. |