Implementation of an MQ-Coder (MQC). More...

Data Structures
struct	opj_mqc_state
	This struct defines the state of a context. More...
struct	opj_mqc
	MQ coder. More...

Macros
#define	MQC_NUMCTXS 19

Typedefs
typedef struct opj_mqc_state	opj_mqc_state_t
	This struct defines the state of a context.
typedef struct opj_mqc	opj_mqc_t
	MQ coder.

Exported functions
#define	mqc_setcurctx(mqc, ctxno)
	Set the current context used for coding/decoding.
opj_mqc_t *	mqc_create (void)
	Create a new MQC handle.
void	mqc_destroy (opj_mqc_t *mqc)
	Destroy a previously created MQC handle.
int	mqc_numbytes (opj_mqc_t *mqc)
	Return the number of bytes written/read since initialisation.
void	mqc_resetstates (opj_mqc_t *mqc)
	Reset the states of all the context of the coder/decoder (each context is set to a state where 0 and 1 are more or less equiprobable).
void	mqc_setstate (opj_mqc_t *mqc, int ctxno, int msb, int prob)
	Set the state of a particular context.
void	mqc_init_enc (opj_mqc_t mqc, unsigned char bp)
	Initialize the encoder.
void	mqc_encode (opj_mqc_t *mqc, int d)
	Encode a symbol using the MQ-coder.
void	mqc_flush (opj_mqc_t *mqc)
	Flush the encoder, so that all remaining data is written.
void	mqc_bypass_init_enc (opj_mqc_t *mqc)
	BYPASS mode switch, initialization operation.
void	mqc_bypass_enc (opj_mqc_t *mqc, int d)
	BYPASS mode switch, coding operation.
int	mqc_bypass_flush_enc (opj_mqc_t *mqc)
	BYPASS mode switch, flush operation.
void	mqc_reset_enc (opj_mqc_t *mqc)
	RESET mode switch.
int	mqc_restart_enc (opj_mqc_t *mqc)
	RESTART mode switch (TERMALL).
void	mqc_restart_init_enc (opj_mqc_t *mqc)
	RESTART mode switch (TERMALL) reinitialisation.
void	mqc_erterm_enc (opj_mqc_t *mqc)
	ERTERM mode switch (PTERM).
void	mqc_segmark_enc (opj_mqc_t *mqc)
	SEGMARK mode switch (SEGSYM).
void	mqc_init_dec (opj_mqc_t mqc, unsigned char bp, int len)
	Initialize the decoder.
int	mqc_decode (opj_mqc_t *const mqc)
	Decode a symbol.

Detailed Description

Implementation of an MQ-Coder (MQC).

The functions in MQC.C have for goal to realize the MQ-coder operations. The functions in MQC.C are used by some function in T1.C.

Macro Definition Documentation

◆ MQC_NUMCTXS

#define MQC_NUMCTXS 19

Referenced by mqc_resetstates().

◆ mqc_setcurctx

#define mqc_setcurctx	(		mqc,
			ctxno )

Value:

(mqc)->curctx = &(mqc)->ctxs[(int)(ctxno)]

Set the current context used for coding/decoding.

Parameters

mqc	MQC handle
ctxno	Number that identifies the context

Referenced by mqc_init_dec(), mqc_init_enc(), mqc_restart_init_enc(), mqc_segmark_enc(), t1_dec_clnpass(), t1_dec_clnpass_step(), t1_dec_clnpass_step_partial(), t1_dec_clnpass_step_vsc(), t1_dec_refpass_step_mqc(), t1_dec_refpass_step_mqc_vsc(), t1_dec_sigpass_step_mqc(), t1_dec_sigpass_step_mqc_vsc(), t1_enc_clnpass(), t1_enc_clnpass_step(), t1_enc_refpass_step(), and t1_enc_sigpass_step().

Typedef Documentation

◆ opj_mqc_state_t

typedef struct opj_mqc_state opj_mqc_state_t

This struct defines the state of a context.

◆ opj_mqc_t

typedef struct opj_mqc opj_mqc_t

MQ coder.

Function Documentation

◆ mqc_bypass_enc()

void mqc_bypass_enc	(	opj_mqc_t *	mqc,
		int	d )

BYPASS mode switch, coding operation.

JPEG 2000 p 505.

Not fully implemented and tested !!

Parameters

mqc	MQC handle
d	The symbol to be encoded (0 or 1)

References opj_mqc::bp, opj_mqc::c, and opj_mqc::ct.

Referenced by t1_enc_refpass_step(), and t1_enc_sigpass_step().

◆ mqc_bypass_flush_enc()

int mqc_bypass_flush_enc ( opj_mqc_t * mqc )

BYPASS mode switch, flush operation.

Not fully implemented and tested !!

Parameters

mqc	MQC handle

Returns: Returns 1 (always)

References opj_mqc::bp, opj_mqc::c, and opj_mqc::ct.

◆ mqc_bypass_init_enc()

void mqc_bypass_init_enc ( opj_mqc_t * mqc )

BYPASS mode switch, initialization operation.

JPEG 2000 p 505.

Not fully implemented and tested !!

Parameters

mqc	MQC handle

References opj_mqc::c, and opj_mqc::ct.

Referenced by t1_encode_cblk().

◆ mqc_create()

opj_mqc_t * mqc_create ( void )

Create a new MQC handle.

Returns: Returns a new MQC handle if successful, returns NULL otherwise

References opj_malloc.

Referenced by t1_create().

◆ mqc_decode()

int mqc_decode ( opj_mqc_t *const mqc )

Decode a symbol.

Parameters

mqc	MQC handle

Returns: Returns the decoded symbol (0 or 1)

References opj_mqc::a, opj_mqc::c, opj_mqc::curctx, mqc_lpsexchange(), mqc_mpsexchange(), and mqc_renormd().

Referenced by t1_dec_clnpass(), t1_dec_clnpass_step(), t1_dec_clnpass_step_partial(), t1_dec_clnpass_step_vsc(), t1_dec_refpass_step_mqc(), t1_dec_refpass_step_mqc_vsc(), t1_dec_sigpass_step_mqc(), and t1_dec_sigpass_step_mqc_vsc().

◆ mqc_destroy()

void mqc_destroy ( opj_mqc_t * mqc )

Destroy a previously created MQC handle.

Parameters

mqc	MQC handle to destroy

References opj_free.

Referenced by t1_destroy().

◆ mqc_encode()

void mqc_encode	(	opj_mqc_t *	mqc,
		int	d )

Encode a symbol using the MQ-coder.

Parameters

mqc	MQC handle
d	The symbol to be encoded (0 or 1)

References opj_mqc::curctx, mqc_codelps(), and mqc_codemps().

Referenced by mqc_segmark_enc(), t1_enc_clnpass(), t1_enc_clnpass_step(), t1_enc_refpass_step(), and t1_enc_sigpass_step().

◆ mqc_erterm_enc()

void mqc_erterm_enc ( opj_mqc_t * mqc )

ERTERM mode switch (PTERM).

Parameters

mqc	MQC handle

References opj_mqc::bp, opj_mqc::c, opj_mqc::ct, and mqc_byteout().

Referenced by t1_encode_cblk().

◆ mqc_flush()

void mqc_flush ( opj_mqc_t * mqc )

Flush the encoder, so that all remaining data is written.

Parameters

mqc	MQC handle

References opj_mqc::bp, opj_mqc::c, opj_mqc::ct, mqc_byteout(), and mqc_setbits().

Referenced by t1_encode_cblk().

◆ mqc_init_dec()

void mqc_init_dec	(	opj_mqc_t *	mqc,
		unsigned char *	bp,
		int	len )

Initialize the decoder.

Parameters

mqc	MQC handle
bp	Pointer to the start of the buffer from which the bytes will be read
len	Length of the input buffer

References opj_mqc::a, opj_mqc::bp, opj_mqc::c, opj_mqc::ct, opj_mqc::end, mqc_bytein(), mqc_setcurctx, opj_realloc, and opj_mqc::start.

Referenced by t1_decode_cblk().

◆ mqc_init_enc()

void mqc_init_enc	(	opj_mqc_t *	mqc,
		unsigned char *	bp )

Initialize the encoder.

Parameters

mqc	MQC handle
bp	Pointer to the start of the buffer where the bytes will be written

References opj_mqc::a, opj_mqc::bp, opj_mqc::c, opj_mqc::ct, mqc_setcurctx, and opj_mqc::start.

Referenced by t1_encode_cblk().

◆ mqc_numbytes()

int mqc_numbytes ( opj_mqc_t * mqc )

Return the number of bytes written/read since initialisation.

Parameters

mqc	MQC handle

Returns: Returns the number of bytes already encoded

References opj_mqc::bp, and opj_mqc::start.

Referenced by t1_encode_cblk().

◆ mqc_reset_enc()

void mqc_reset_enc ( opj_mqc_t * mqc )

RESET mode switch.

Parameters

mqc	MQC handle

References mqc_resetstates(), mqc_setstate(), T1_CTXNO_AGG, T1_CTXNO_UNI, and T1_CTXNO_ZC.

Referenced by t1_encode_cblk().

◆ mqc_resetstates()

void mqc_resetstates ( opj_mqc_t * mqc )

Reset the states of all the context of the coder/decoder (each context is set to a state where 0 and 1 are more or less equiprobable).

Parameters

mqc	MQC handle

References opj_mqc::ctxs, MQC_NUMCTXS, and mqc_states.

Referenced by mqc_reset_enc(), t1_decode_cblk(), and t1_encode_cblk().

◆ mqc_restart_enc()

int mqc_restart_enc ( opj_mqc_t * mqc )

RESTART mode switch (TERMALL).

Parameters

mqc	MQC handle

Returns: Returns 1 (always)

References opj_mqc::c, opj_mqc::ct, and mqc_byteout().

◆ mqc_restart_init_enc()

void mqc_restart_init_enc ( opj_mqc_t * mqc )

RESTART mode switch (TERMALL) reinitialisation.

Parameters

mqc	MQC handle

References opj_mqc::a, opj_mqc::bp, opj_mqc::c, opj_mqc::ct, and mqc_setcurctx.

Referenced by t1_encode_cblk().

◆ mqc_segmark_enc()

void mqc_segmark_enc ( opj_mqc_t * mqc )

SEGMARK mode switch (SEGSYM).

Parameters

mqc	MQC handle

References mqc_encode(), and mqc_setcurctx.

Referenced by t1_encode_cblk().

◆ mqc_setstate()

void mqc_setstate	(	opj_mqc_t *	mqc,
		int	ctxno,
		int	msb,
		int	prob )

Set the state of a particular context.

Parameters

mqc	MQC handle
ctxno	Number that identifies the context
msb	The MSB of the new state of the context
prob	Number that identifies the probability of the symbols for the new state of the context

References opj_mqc::ctxs, and mqc_states.

Referenced by mqc_reset_enc(), t1_decode_cblk(), and t1_encode_cblk().

Data Structures

Macros

Typedefs

Exported functions

Detailed Description

Macro Definition Documentation

◆ MQC_NUMCTXS

◆ mqc_setcurctx

Typedef Documentation

◆ opj_mqc_state_t

◆ opj_mqc_t

Function Documentation

◆ mqc_bypass_enc()

Not fully implemented and tested !!

◆ mqc_bypass_flush_enc()

Not fully implemented and tested !!

◆ mqc_bypass_init_enc()

Not fully implemented and tested !!

◆ mqc_create()

◆ mqc_decode()

◆ mqc_destroy()

◆ mqc_encode()

◆ mqc_erterm_enc()

◆ mqc_flush()

◆ mqc_init_dec()

◆ mqc_init_enc()

◆ mqc_numbytes()

◆ mqc_reset_enc()

◆ mqc_resetstates()

◆ mqc_restart_enc()

◆ mqc_restart_init_enc()

◆ mqc_segmark_enc()

◆ mqc_setstate()