VLCDecodeUTupleEscBlock

Parses the bitstream and decodes variable length code for AAC using unsigned multi-tupled VLC tables.

Syntax

IppStatus ippsVLCDecodeUTupleEscBlock_AAC_1u16s(Ipp8u **ppBitStream, int *pBitOffset, Ipp16s *pData, int len, const IppsVLCDecodeUTupleSpec_32s *pVLCSpec);

Parameters

ppBitStream	Pointer to pointer to the current byte in the bitstream buffer. ppBitStream is updated by the function.
pBitOffset	Pointer to the bit position in the byte pointed by ppBitStream. Valid within the range 0 to 7. pBitOffset is updated by the function.
pData	Pointer to the array of decoded values.
len	Number of samples to decode into pDataarray.
pVLCSpec	Pointer to VLCDecoder specification structure.

Description

The function ippsVLCDecodeUTupleEscBlock_AACis declared in the ippac.h header file. The function parses the bitstream and decodes variable length code using the VLCDecoder specification structure built by the function ippsVLCDecodeUTupleInit_32s or ippsVLCDecodeUTupleInitAlloc_32s from data compression domain, and resets the pointers to new positions. The pointer pBitStream points to the 8-bit value and the bit offset may vary from one to 32. After processing, the pointer and bit offset are changed and their new values are returned. To use the function ippsVLCDecodeUTupleEscBlock_AAC, rearrange inputTable before initialization as a 2-tuple table.

Return Values

ippStsNoErr	Indicates no error.
ippStsNullPtrErr	Indicates an error when one of the specified pointers is NULL.
ippStsBitOffsetErr	Indicates an error when pBitOffset is less than 0 or more than 7.
ippStsContextMatchErr	Indicates an error when pVLCSpec structure does not match the operation.
ippStsVLCInputDataErr	Indicates an error when incorrect input is used. For decode functions, it can indicate that the bitstream contains code that is not specified inside the table used.
ippStsVLCAACEscCodeLengthErr	Indicates an error when the bitstream contains AAC-Esc code with the length exceeding 21.