DCTInvGetBufSize

Determines the size of work buffer that can be used by the inverse DCT function.

Syntax

IppStatus ippiDCTInvGetBufSize_32f (IppiDCTInvSpec_32f* pDCTSpec, int* pBufferSize);

Parameters

pDCTSpec	Pointer to the previously initialized inverse DCT context structure.
pBufferSize	Pointer to the size of the external work buffer to be used by the inverse DCT function.

Description

The function ippiDCTInvGetBufSize is declared in the ippi.h file. This function determines the size in bytes of an external memory buffer that can be used by the inverse DCT function with context pDCTSpec as a workspace during calculations.

If you want to use external buffering, call this function after pDCTSpec initialization. Use the computed pBufferSize value as the size in bytes of an external buffer to be allocated by means of the functions ippMalloc or ippsMalloc_8u. Note that the allocated memory can be freed only by the functions ippFree or ippsFree respectively. Refer to the “Support Functions” in the Intel IPP Reference Manual, vol.1 for more details about the memory allocation functions.

Return Values

ippStsNoErr	Indicates no error. Any other value indicates an error or a warning.
ippStsNullPtrErr	Indicates an error condition if pDCTSpec pointer is `NULL`.
ippStsContextMatchErr	Indicates an error condition if a pointer to an invalid pDCTSpec structure is passed.