EncodeLoadCodeBlock

Loads a code block and prepares data for entropy encoding.

Syntax

IppStatus ippiEncodeLoadCodeBlock_JPEG2K_32s_C1R(const Ipp32s* pSrc, int srcStep, IppiSize codeBlockSize, IppiEncodeState_JPEG2K* pState, IppiWTSubband subband, int magnBits, IppiMQTermination mqTermType, IppiMQRateAppr mqRateAppr, int codeStyleFlags, int* pSfBits, int* pNOfPasses, int* pNOfTermPasses);

Parameters

pSrc	Pointer to the source code block.
srcStep	Distance in bytes between starts of consecutive lines in the code block.
codeBlockSize	Size of the code block.
pState	Pointer to allocated and initialized encoder state structure.
subband	Wavelet transform subband contained the given code block. Possible values are listed in the Table “Subband Parameter for the JPEG2000 Entropy Coder Functions”.
magnBits	Non-fractional bit count in integer representation.
codeStyleFlags	Specifies the options for encoding procedure. The possible values are listed in the Table “CodeStyleFlag Argument for the JPEG2000 Entropy Coder Functions”.
mqTermType	Termination mode for MQ-coder. Possible values are listed in the Table “MqTermType Argument for the JPEG2000 Entropy Coder Functions”.
mqRateAppr	Specifies the bit rate estimation model. Only one value, ippMQRateApprGood, that sets the non-optimal approximation model is available now.
pSfBits	Pointer to the variable that returns the number of significant bit planes.
pNOfPasses	Pointer to the variable that returns the number of coding passes.
pNOfTermPasses	Pointer to the variable that returns the number of terminated coding passes.

Description

The function ippiEncodeLoadCodeBlock_JPEG2K is declared in the ippj.h file. This function performs the first encoding procedure, that is, loads the specified code block, computes required parameters of the MQ-coder, and prepares data for the second encoding procedure. The wavelet transform subband should be specified in the subband parameter. Possible values are listed in the Table “Subband Parameter for the JPEG2000 Entropy Coder Functions”.

Subband Parameter for the JPEG2000 Entropy Coder Functions
Value	Description
ippWTSubbandLxLy	Subband obtained by low-pass filtering along x and y directions
ippWTSubbandLxHy	Subband obtained by low-pass filtering along x and high-pass filtering along y direction
ippWTSubbandHxLy	Subband obtained by high-pass filtering along x and low-pass filtering along y direction
ippWTSubbandHxHy	Subband obtained by high-pass filtering along x and y directions

CodeStyleFlag Argument for the JPEG2000 Entropy Coder Functions
Value	Description
IPP_JPEG2K_VERTICALLY_CAUSAL_CONTEXT	Sets the creation of vertically causal context
IPP_JPEG2K_SELECTIVE_MQ_BYPASS	Sets the selective MQ encoding bypass, which is raw encoding for some coding passes
IPP_JPEG2K_TERMINATE_ON_EVERY_PASS	Sets the termination of MQ coder after every coding pass
IPP_JPEG2K_RESETCTX_ON_EVERY_PASS	Sets the reset of MQ coder context after each coding pass
IPP_JPEG2K_USE_SEGMENTATION_SYMBOLS	Uses the segmentation symbol sequence for error resilience
IPP_JPEG2K_LOSSLESS_MODE	Indicates that the lossless wavelet transforms are used in the rate-distortion estimation
IPP_JPEG2K_DEC_CONCEAL_ERRORS	Allows the error concealment in the last bit-plane where the errors were detected
IPP_JPEG2K_DEC_DO_NOT_CLEAR_CB	Does not clear the code block data before decoding
IPP_JPEG2K_DEC_DO_NOT_RESET_LOW_BITS	Does not reset low-order bits after decoding
IPP_JPEG2K_DEC_DO_NOT_CLEAR_SFBUFFER	Does not clear the buffer before decoding to keep the previous significance state
IPP_JPEG2K_DEC_CHECK_PRED_TERM	Verifies during decoding if the predictable termination is correct; if not - “damage in codeblock” error code is generated. It should be used in predictable termination mode.

MqTermType Argument for the JPEG2000 Entropy Coder Functions
Value	Description
ippMQTermSimple	Simple termination - some extra bytes are added
ippMQTermNearOptimal	Near optimal termination mode
ippMQTermPredictable	Termination mode for predictable error resilience

The variable sfBits returns the number of significant bit planes only. For example, if all source pixels are non-negative and their maximum value is 0xA (binary 1010), then sfBits should return 4 significant bits. The higher bits are not coded.

Only significant non-fractional bits in integer representation are coded. magnBits specifies the number of non-fractional bits. For example, if magnBits = 11, the 20 (31-11) least significant bits will not be coded.

Negative integers in the code block should be presented in direct code with the sign in the most significant bit (31^st in the zero-based numeration, when the least significant bit has a zero index). This code may be effectively obtained using the specially designed function ippiComplement.

Return Values

ippStsNoErr	Indicates no error.
ippStsNullPtrErr	Indicates an error when any of the specified pointers is `NULL`.
ippStsSizeErr	Indicates an error condition if the width or height of the code block has zero or negative value.
ippStsContextMatchErr	Indicates an error condition if a pointer to an invalid state structure is passed.
ippStsStepErr	Indicates an error condition if srcStep has zero or negative value.