VLCCountEscBits

Calculates the number of bits necessary for encoding in AAC format.

Syntax

IppStatus ippsVLCCountEscBits_AAC_16s32s(const Ipp16s* pInputData, int len, Ipp32s* pCountBits, const IppsVLCEncodeSpec_32s* pVLCSpec);

Parameters

pInputData	Pointer to the array of source values.
len	Size of values array pInputData.
pCountBits	Pointer to calculated length in bits to encode pInputData.
pVLCSpec	Pointer to VLCEncoder specification structure.

Description

The function ippsVLCCountEscBits_AAC is declared in the ippac.h header file. The function calculates the number of bits necessary for encoding source data in pInputData, using the VLCEncoder specification structure built by the function ippsVLCEncodeInit_32s or ippsVLCEncodeInitAlloc_32s from data compression domain. To use the function ippsVLCCountEscBits_AAC, rearrange inputTable before initialization in the same way as described in the description of ippsVLCDecodeEscBlock_AAC with one exception (because the large absolute value is equal to 16):

value = (first_sample_value << 6) + (second_sample_value + 16).

The function ippsVLCCountEscBits_AAC_16s32s is used in the float-point and fixed-point versions of AAC encoder included into IPP Samples. See introduction to this section.

Return Values

ippStsNoErr	Indicates no error.
ippStsNullPtrErr	Indicates an error when one of the specified pointers is NULL.
ippStsContextMatchErr	Indicates an error when pVLCSpec structure does not match the operation.