/* * 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 * * $Id$ */ #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_least32_t creg; 	/* The A register. */	uint_least32_t areg; 	/* The CT register. */	uint_least32_t ctreg; 	/* The current context. */	const jpc_mqstate_t **curctx; 	/* The per-context information. */	const jpc_mqstate_t **ctxs; 	/* The maximum number of contexts. */	unsigned maxctxs; 	/* The stream from which to read data. */	jas_stream_t *in; 	/* The last character read. */	jas_uchar inbuffer; 	/* The EOF indicator. */	bool eof; } jpc_mqdec_t; /******************************************************************************\* Functions/macros for construction and destruction.\******************************************************************************/ /* Create a MQ decoder. */jpc_mqdec_t *jpc_mqdec_create(unsigned 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. */static inline void jpc_mqdec_setcurctx(jpc_mqdec_t *dec, unsigned ctxno){	dec->curctx = &dec->ctxs[ctxno];} /* Set the state information for all contexts of a MQ decoder. */void jpc_mqdec_setctxs(const jpc_mqdec_t *dec, unsigned numctxs, const jpc_mqctx_t *ctxs); /******************************************************************************\* Functions/macros for decoding bits.\******************************************************************************/ /* Decode a symbol. */#ifdef NDEBUG#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). */#ifdef NDEBUG#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(const jpc_mqdec_t *dec); /******************************************************************************\* 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.\******************************************************************************/ bool jpc_mqdec_mpsexchrenormd(jpc_mqdec_t *dec);bool jpc_mqdec_lpsexchrenormd(jpc_mqdec_t *dec); JAS_FORCE_INLINEstatic bool jpc_mqdec_getbit_macro(jpc_mqdec_t *dec){	const jpc_mqstate_t *const state = *dec->curctx; 	dec->areg -= state->qeval; 	if (dec->creg >= (uint_least32_t)state->qeval << 16) {		dec->creg -= (uint_least32_t)state->qeval << 16;		return dec->areg & 0x8000			? state->mps			: jpc_mqdec_mpsexchrenormd(dec);	} else {		return jpc_mqdec_lpsexchrenormd(dec);	}} JAS_FORCE_INLINEstatic bool jpc_mqdec_mpsexchange(uint_least32_t areg, uint_least32_t delta, const jpc_mqstate_t **curctx){	if (areg < delta) {		const jpc_mqstate_t *state = *curctx;		/* LPS decoded. */		*curctx = state->nlps;		return !state->mps;	} else {		const jpc_mqstate_t *state = *curctx;		/* MPS decoded. */		*curctx = state->nmps;		return state->mps;	}} JAS_FORCE_INLINEstatic bool jpc_mqdec_lpsexchange(uint_least32_t *areg_p, uint_least32_t delta, const jpc_mqstate_t **curctx){	if (*areg_p >= delta) {		const jpc_mqstate_t *state = *curctx;		*areg_p = delta;		*curctx = state->nlps;		return !state->mps;	} else {		const jpc_mqstate_t *state = *curctx;		*areg_p = delta;		*curctx = state->nmps;		return state->mps;	}} bool jpc_mqdec_getbit_func(jpc_mqdec_t *dec); #endif