/*
* Copyright (c) 1999-2000 Image Power, Inc. and the University of
* British Columbia.
* Copyright (c) 2001-2003 Michael David Adams.
* All rights reserved.
*/
/* __START_OF_JASPER_LICENSE__
*
* JasPer License Version 2.0
*
* Copyright (c) 2001-2006 Michael David Adams
* Copyright (c) 1999-2000 Image Power, Inc.
* Copyright (c) 1999-2000 The University of British Columbia
*
* All rights reserved.
*
* Permission is hereby granted, free of charge, to any person (the
* "User") obtaining a copy of this software and associated documentation
* files (the "Software"), to deal in the Software without restriction,
* including without limitation the rights to use, copy, modify, merge,
* publish, distribute, and/or sell copies of the Software, and to permit
* persons to whom the Software is furnished to do so, subject to the
* following conditions:
*
* 1. The above copyright notices and this permission notice (which
* includes the disclaimer below) shall be included in all copies or
* substantial portions of the Software.
*
* 2. The name of a copyright holder shall not be used to endorse or
* promote products derived from the Software without specific prior
* written permission.
*
* THIS DISCLAIMER OF WARRANTY CONSTITUTES AN ESSENTIAL PART OF THIS
* LICENSE. NO USE OF THE SOFTWARE IS AUTHORIZED HEREUNDER EXCEPT UNDER
* THIS DISCLAIMER. THE SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS
* "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR IMPLIED, INCLUDING
* BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY, FITNESS FOR A
* PARTICULAR PURPOSE AND NONINFRINGEMENT OF THIRD PARTY RIGHTS. IN NO
* EVENT SHALL THE COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, OR ANY SPECIAL
* INDIRECT OR CONSEQUENTIAL DAMAGES, OR ANY DAMAGES WHATSOEVER RESULTING
* FROM LOSS OF USE, DATA OR PROFITS, WHETHER IN AN ACTION OF CONTRACT,
* NEGLIGENCE OR OTHER TORTIOUS ACTION, ARISING OUT OF OR IN CONNECTION
* WITH THE USE OR PERFORMANCE OF THIS SOFTWARE. NO ASSURANCES ARE
* PROVIDED BY THE COPYRIGHT HOLDERS THAT THE SOFTWARE DOES NOT INFRINGE
* THE PATENT OR OTHER INTELLECTUAL PROPERTY RIGHTS OF ANY OTHER ENTITY.
* EACH COPYRIGHT HOLDER DISCLAIMS ANY LIABILITY TO THE USER FOR CLAIMS
* BROUGHT BY ANY OTHER ENTITY BASED ON INFRINGEMENT OF INTELLECTUAL
* PROPERTY RIGHTS OR OTHERWISE. AS A CONDITION TO EXERCISING THE RIGHTS
* GRANTED HEREUNDER, EACH USER HEREBY ASSUMES SOLE RESPONSIBILITY TO SECURE
* ANY OTHER INTELLECTUAL PROPERTY RIGHTS NEEDED, IF ANY. THE SOFTWARE
* IS NOT FAULT-TOLERANT AND IS NOT INTENDED FOR USE IN MISSION-CRITICAL
* SYSTEMS, SUCH AS THOSE USED IN THE OPERATION OF NUCLEAR FACILITIES,
* AIRCRAFT NAVIGATION OR COMMUNICATION SYSTEMS, AIR TRAFFIC CONTROL
* SYSTEMS, DIRECT LIFE SUPPORT MACHINES, OR WEAPONS SYSTEMS, IN WHICH
* THE FAILURE OF THE SOFTWARE OR SYSTEM COULD LEAD DIRECTLY TO DEATH,
* PERSONAL INJURY, OR SEVERE PHYSICAL OR ENVIRONMENTAL DAMAGE ("HIGH
* RISK ACTIVITIES"). THE COPYRIGHT HOLDERS SPECIFICALLY DISCLAIM ANY
* EXPRESS OR IMPLIED WARRANTY OF FITNESS FOR HIGH RISK ACTIVITIES.
*
* __END_OF_JASPER_LICENSE__
*/
/*
* MQ Arithmetic Decoder
*
* $Id: jpc_mqdec.h,v 1.2 2008-05-26 09:40:52 vp153 Exp $
*/
#ifndef JPC_MQDEC_H
#define JPC_MQDEC_H
/******************************************************************************\
* Includes.
\******************************************************************************/
#include "jasper/jas_types.h"
#include "jasper/jas_stream.h"
#include "jpc_mqcod.h"
/******************************************************************************\
* Types.
\******************************************************************************/
/* MQ arithmetic decoder. */
typedef struct {
/* The C register. */
uint_fast32_t creg;
/* The A register. */
uint_fast32_t areg;
/* The CT register. */
uint_fast32_t ctreg;
/* The current context. */
jpc_mqstate_t **curctx;
/* The per-context information. */
jpc_mqstate_t **ctxs;
/* The maximum number of contexts. */
int maxctxs;
/* The stream from which to read data. */
jas_stream_t *in;
/* The last character read. */
uchar inbuffer;
/* The EOF indicator. */
int eof;
} jpc_mqdec_t;
/******************************************************************************\
* Functions/macros for construction and destruction.
\******************************************************************************/
/* Create a MQ decoder. */
jpc_mqdec_t *jpc_mqdec_create(int maxctxs, jas_stream_t *in);
/* Destroy a MQ decoder. */
void jpc_mqdec_destroy(jpc_mqdec_t *dec);
/******************************************************************************\
* Functions/macros for initialization.
\******************************************************************************/
/* Set the input stream associated with a MQ decoder. */
void jpc_mqdec_setinput(jpc_mqdec_t *dec, jas_stream_t *in);
/* Initialize a MQ decoder. */
void jpc_mqdec_init(jpc_mqdec_t *dec);
/******************************************************************************\
* Functions/macros for manipulating contexts.
\******************************************************************************/
/* Set the current context for a MQ decoder. */
#define jpc_mqdec_setcurctx(dec, ctxno) \
((mqdec)->curctx = &(mqdec)->ctxs[ctxno]);
/* Set the state information for a particular context of a MQ decoder. */
void jpc_mqdec_setctx(jpc_mqdec_t *dec, int ctxno, jpc_mqctx_t *ctx);
/* Set the state information for all contexts of a MQ decoder. */
void jpc_mqdec_setctxs(jpc_mqdec_t *dec, int numctxs, jpc_mqctx_t *ctxs);
/******************************************************************************\
* Functions/macros for decoding bits.
\******************************************************************************/
/* Decode a symbol. */
#if !defined(DEBUG)
#define jpc_mqdec_getbit(dec) \
jpc_mqdec_getbit_macro(dec)
#else
#define jpc_mqdec_getbit(dec) \
jpc_mqdec_getbit_func(dec)
#endif
/* Decode a symbol (assuming an unskewed probability distribution). */
#if !defined(DEBUG)
#define jpc_mqdec_getbitnoskew(dec) \
jpc_mqdec_getbit_macro(dec)
#else
#define jpc_mqdec_getbitnoskew(dec) \
jpc_mqdec_getbit_func(dec)
#endif
/******************************************************************************\
* Functions/macros for debugging.
\******************************************************************************/
/* Dump the MQ decoder state for debugging. */
void jpc_mqdec_dump(jpc_mqdec_t *dec, FILE *out);
/******************************************************************************\
* EVERYTHING BELOW THIS POINT IS IMPLEMENTATION SPECIFIC AND NOT PART OF THE
* APPLICATION INTERFACE. DO NOT RELY ON ANY OF THE INTERNAL FUNCTIONS/MACROS
* GIVEN BELOW.
\******************************************************************************/
#define jpc_mqdec_getbit_macro(dec) \
((((dec)->areg -= (*(dec)->curctx)->qeval), \
(dec)->creg >> 16 >= (*(dec)->curctx)->qeval) ? \
((((dec)->creg -= (*(dec)->curctx)->qeval << 16), \
(dec)->areg & 0x8000) ? (*(dec)->curctx)->mps : \
jpc_mqdec_mpsexchrenormd(dec)) : \
jpc_mqdec_lpsexchrenormd(dec))
#define jpc_mqdec_mpsexchange(areg, delta, curctx, bit) \
{ \
if ((areg) < (delta)) { \
register jpc_mqstate_t *state = *(curctx); \
/* LPS decoded. */ \
(bit) = state->mps ^ 1; \
*(curctx) = state->nlps; \
} else { \
register jpc_mqstate_t *state = *(curctx); \
/* MPS decoded. */ \
(bit) = state->mps; \
*(curctx) = state->nmps; \
} \
}
#define jpc_mqdec_lpsexchange(areg, delta, curctx, bit) \
{ \
if ((areg) >= (delta)) { \
register jpc_mqstate_t *state = *(curctx); \
(areg) = (delta); \
(bit) = state->mps ^ 1; \
*(curctx) = state->nlps; \
} else { \
register jpc_mqstate_t *state = *(curctx); \
(areg) = (delta); \
(bit) = state->mps; \
*(curctx) = state->nmps; \
} \
}
#define jpc_mqdec_renormd(areg, creg, ctreg, in, eof, inbuf) \
{ \
do { \
if (!(ctreg)) { \
jpc_mqdec_bytein2(creg, ctreg, in, eof, inbuf); \
} \
(areg) <<= 1; \
(creg) <<= 1; \
--(ctreg); \
} while (!((areg) & 0x8000)); \
}
#define jpc_mqdec_bytein2(creg, ctreg, in, eof, inbuf) \
{ \
int c; \
unsigned char prevbuf; \
if (!(eof)) { \
if ((c = jas_stream_getc(in)) == EOF) { \
(eof) = 1; \
c = 0xff; \
} \
prevbuf = (inbuf); \
(inbuf) = c; \
if (prevbuf == 0xff) { \
if (c > 0x8f) { \
(creg) += 0xff00; \
(ctreg) = 8; \
} else { \
(creg) += c << 9; \
(ctreg) = 7; \
} \
} else { \
(creg) += c << 8; \
(ctreg) = 8; \
} \
} else { \
(creg) += 0xff00; \
(ctreg) = 8; \
} \
}
int jpc_mqdec_getbit_func(jpc_mqdec_t *dec);
int jpc_mqdec_mpsexchrenormd(jpc_mqdec_t *dec);
int jpc_mqdec_lpsexchrenormd(jpc_mqdec_t *dec);
#endif