/*
* Copyright (c) 2001-2003, David Janssens
* Copyright (c) 2002-2003, Yannick Verschueren
* Copyright (c) 2003-2005, Francois Devaux and Antonin Descampe
* Copyright (c) 2005, Hervé Drolon, FreeImage Team
* Copyright (c) 2002-2005, Communications and remote sensing Laboratory, Universite catholique de Louvain, Belgium
* All rights reserved.
*
* Redistribution and use in source and binary forms, with or without
* modification, are permitted provided that the following conditions
* are met:
* 1. Redistributions of source code must retain the above copyright
* notice, this list of conditions and the following disclaimer.
* 2. Redistributions in binary form must reproduce the above copyright
* notice, this list of conditions and the following disclaimer in the
* documentation and/or other materials provided with the distribution.
*
* THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS `AS IS'
* AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
* IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
* ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT OWNER OR CONTRIBUTORS BE
* LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR
* CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF
* SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS
* INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN
* CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE)
* ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE
* POSSIBILITY OF SUCH DAMAGE.
*/
#ifndef __MQC_H
#define __MQC_H
/**
@file mqc.h
@brief 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.
*/
/** @defgroup MQC MQC - Implementation of an MQ-Coder */
/*@{*/
/**
This struct defines the state of a context.
*/
typedef struct opj_mqc_state {
/** the probability of the Least Probable Symbol (0.75->0x8000, 1.5->0xffff) */
unsigned int qeval;
/** the Most Probable Symbol (0 or 1) */
int mps;
/** next state if the next encoded symbol is the MPS */
struct opj_mqc_state *nmps;
/** next state if the next encoded symbol is the LPS */
struct opj_mqc_state *nlps;
} opj_mqc_state_t;
#define MQC_NUMCTXS 32
/**
MQ coder
*/
typedef struct opj_mqc {
unsigned int c;
unsigned int a;
unsigned int ct;
unsigned char *bp;
unsigned char *start;
unsigned char *end;
opj_mqc_state_t *ctxs[MQC_NUMCTXS];
opj_mqc_state_t **curctx;
} opj_mqc_t;
/** @name Exported functions */
/*@{*/
/* ----------------------------------------------------------------------- */
/**
Create a new MQC handle
@return Returns a new MQC handle if successful, returns NULL otherwise
*/
opj_mqc_t* mqc_create();
/**
Destroy a previously created MQC handle
@param mqc MQC handle to destroy
*/
void mqc_destroy(opj_mqc_t *mqc);
/**
Return the number of bytes written/read since initialisation
@param mqc MQC handle
@return Returns the number of bytes already encoded
*/
int mqc_numbytes(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)
@param mqc MQC handle
*/
void mqc_resetstates(opj_mqc_t *mqc);
/**
Set the state of a particular context
@param mqc MQC handle
@param ctxno Number that identifies the context
@param msb The MSB of the new state of the context
@param prob Number that identifies the probability of the symbols for the new state of the context
*/
void mqc_setstate(opj_mqc_t *mqc, int ctxno, int msb, int prob);
/**
Initialize the encoder
@param mqc MQC handle
@param bp Pointer to the start of the buffer where the bytes will be written
*/
void mqc_init_enc(opj_mqc_t *mqc, unsigned char *bp);
/**
Set the current context used for coding/decoding
@param mqc MQC handle
@param ctxno Number that identifies the context
*/
void mqc_setcurctx(opj_mqc_t *mqc, int ctxno);
/**
Encode a symbol using the MQ-coder
@param mqc MQC handle
@param d The symbol to be encoded (0 or 1)
*/
void mqc_encode(opj_mqc_t *mqc, int d);
/**
Flush the encoder, so that all remaining data is written
@param mqc MQC handle
*/
void mqc_flush(opj_mqc_t *mqc);
/**
BYPASS mode switch, initialization operation.
JPEG 2000 p 505.
<h2>Not fully implemented and tested !!</h2>
@param mqc MQC handle
*/
void mqc_bypass_init_enc(opj_mqc_t *mqc);
/**
BYPASS mode switch, coding operation.
JPEG 2000 p 505.
<h2>Not fully implemented and tested !!</h2>
@param mqc MQC handle
@param d The symbol to be encoded (0 or 1)
*/
void mqc_bypass_enc(opj_mqc_t *mqc, int d);
/**
BYPASS mode switch, flush operation
<h2>Not fully implemented and tested !!</h2>
@param mqc MQC handle
@return Returns 1 (always)
*/
int mqc_bypass_flush_enc(opj_mqc_t *mqc);
/**
RESET mode switch
@param mqc MQC handle
*/
void mqc_reset_enc(opj_mqc_t *mqc);
/**
RESET mode switch
@param mqc MQC handle
*/
void mqc_reset_enc_3(opj_mqc_t *mqc);
/**
RESTART mode switch (TERMALL)
@param mqc MQC handle
@return Returns 1 (always)
*/
int mqc_restart_enc(opj_mqc_t *mqc);
/**
RESTART mode switch (TERMALL) reinitialisation
@param mqc MQC handle
*/
void mqc_restart_init_enc(opj_mqc_t *mqc);
/**
ERTERM mode switch (PTERM)
@param mqc MQC handle
*/
void mqc_erterm_enc(opj_mqc_t *mqc);
/**
SEGMARK mode switch (SEGSYM)
@param mqc MQC handle
*/
void mqc_segmark_enc(opj_mqc_t *mqc);
/**
Initialize the decoder
@param mqc MQC handle
@param bp Pointer to the start of the buffer from which the bytes will be read
@param len Length of the input buffer
*/
void mqc_init_dec(opj_mqc_t *mqc, unsigned char *bp, int len);
/**
Decode a symbol
@param mqc MQC handle
@return Returns the decoded symbol (0 or 1)
*/
int mqc_decode(opj_mqc_t *mqc);
/* ----------------------------------------------------------------------- */
/*@}*/
/*@}*/
#endif /* __MQC_H */