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      1 /*
      2  * Copyright (c) 1999-2000 Image Power, Inc. and the University of
      3  *   British Columbia.
      4  * Copyright (c) 2001-2002 Michael David Adams.
      5  * All rights reserved.
      6  */
      7 
      8 /* __START_OF_JASPER_LICENSE__
      9  *
     10  * JasPer License Version 2.0
     11  *
     12  * Copyright (c) 2001-2006 Michael David Adams
     13  * Copyright (c) 1999-2000 Image Power, Inc.
     14  * Copyright (c) 1999-2000 The University of British Columbia
     15  *
     16  * All rights reserved.
     17  *
     18  * Permission is hereby granted, free of charge, to any person (the
     19  * "User") obtaining a copy of this software and associated documentation
     20  * files (the "Software"), to deal in the Software without restriction,
     21  * including without limitation the rights to use, copy, modify, merge,
     22  * publish, distribute, and/or sell copies of the Software, and to permit
     23  * persons to whom the Software is furnished to do so, subject to the
     24  * following conditions:
     25  *
     26  * 1.  The above copyright notices and this permission notice (which
     27  * includes the disclaimer below) shall be included in all copies or
     28  * substantial portions of the Software.
     29  *
     30  * 2.  The name of a copyright holder shall not be used to endorse or
     31  * promote products derived from the Software without specific prior
     32  * written permission.
     33  *
     34  * THIS DISCLAIMER OF WARRANTY CONSTITUTES AN ESSENTIAL PART OF THIS
     35  * LICENSE.  NO USE OF THE SOFTWARE IS AUTHORIZED HEREUNDER EXCEPT UNDER
     36  * THIS DISCLAIMER.  THE SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS
     37  * "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR IMPLIED, INCLUDING
     38  * BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY, FITNESS FOR A
     39  * PARTICULAR PURPOSE AND NONINFRINGEMENT OF THIRD PARTY RIGHTS.  IN NO
     40  * EVENT SHALL THE COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, OR ANY SPECIAL
     41  * INDIRECT OR CONSEQUENTIAL DAMAGES, OR ANY DAMAGES WHATSOEVER RESULTING
     42  * FROM LOSS OF USE, DATA OR PROFITS, WHETHER IN AN ACTION OF CONTRACT,
     43  * NEGLIGENCE OR OTHER TORTIOUS ACTION, ARISING OUT OF OR IN CONNECTION
     44  * WITH THE USE OR PERFORMANCE OF THIS SOFTWARE.  NO ASSURANCES ARE
     45  * PROVIDED BY THE COPYRIGHT HOLDERS THAT THE SOFTWARE DOES NOT INFRINGE
     46  * THE PATENT OR OTHER INTELLECTUAL PROPERTY RIGHTS OF ANY OTHER ENTITY.
     47  * EACH COPYRIGHT HOLDER DISCLAIMS ANY LIABILITY TO THE USER FOR CLAIMS
     48  * BROUGHT BY ANY OTHER ENTITY BASED ON INFRINGEMENT OF INTELLECTUAL
     49  * PROPERTY RIGHTS OR OTHERWISE.  AS A CONDITION TO EXERCISING THE RIGHTS
     50  * GRANTED HEREUNDER, EACH USER HEREBY ASSUMES SOLE RESPONSIBILITY TO SECURE
     51  * ANY OTHER INTELLECTUAL PROPERTY RIGHTS NEEDED, IF ANY.  THE SOFTWARE
     52  * IS NOT FAULT-TOLERANT AND IS NOT INTENDED FOR USE IN MISSION-CRITICAL
     53  * SYSTEMS, SUCH AS THOSE USED IN THE OPERATION OF NUCLEAR FACILITIES,
     54  * AIRCRAFT NAVIGATION OR COMMUNICATION SYSTEMS, AIR TRAFFIC CONTROL
     55  * SYSTEMS, DIRECT LIFE SUPPORT MACHINES, OR WEAPONS SYSTEMS, IN WHICH
     56  * THE FAILURE OF THE SOFTWARE OR SYSTEM COULD LEAD DIRECTLY TO DEATH,
     57  * PERSONAL INJURY, OR SEVERE PHYSICAL OR ENVIRONMENTAL DAMAGE ("HIGH
     58  * RISK ACTIVITIES").  THE COPYRIGHT HOLDERS SPECIFICALLY DISCLAIM ANY
     59  * EXPRESS OR IMPLIED WARRANTY OF FITNESS FOR HIGH RISK ACTIVITIES.
     60  *
     61  * __END_OF_JASPER_LICENSE__
     62  */
     63 
     64 /*
     65  * MQ Arithmetic Encoder
     66  *
     67  * $Id: jpc_mqenc.h,v 1.2 2008-05-26 09:40:52 vp153 Exp $
     68  */
     69 
     70 #ifndef JPC_MQENC_H
     71 #define JPC_MQENC_H
     72 
     73 /******************************************************************************\
     74 * Includes.
     75 \******************************************************************************/
     76 
     77 #include "jasper/jas_types.h"
     78 #include "jasper/jas_stream.h"
     79 
     80 #include "jpc_mqcod.h"
     81 
     82 /******************************************************************************\
     83 * Constants.
     84 \******************************************************************************/
     85 
     86 /*
     87  * Termination modes.
     88  */
     89 
     90 #define	JPC_MQENC_DEFTERM	0	/* default termination */
     91 #define	JPC_MQENC_PTERM		1	/* predictable termination */
     92 
     93 /******************************************************************************\
     94 * Types.
     95 \******************************************************************************/
     96 
     97 /* MQ arithmetic encoder class. */
     98 
     99 typedef struct {
    100 
    101     /* The C register. */
    102     uint_fast32_t creg;
    103 
    104     /* The A register. */
    105     uint_fast32_t areg;
    106 
    107     /* The CT register. */
    108     uint_fast32_t ctreg;
    109 
    110     /* The maximum number of contexts. */
    111     int maxctxs;
    112 
    113     /* The per-context information. */
    114     jpc_mqstate_t **ctxs;
    115 
    116     /* The current context. */
    117     jpc_mqstate_t **curctx;
    118 
    119     /* The stream for encoder output. */
    120     jas_stream_t *out;
    121 
    122     /* The byte buffer (i.e., the B variable in the standard). */
    123     int_fast16_t outbuf;
    124 
    125     /* The last byte output. */
    126     int_fast16_t lastbyte;
    127 
    128     /* The error indicator. */
    129     int err;
    130 
    131 } jpc_mqenc_t;
    132 
    133 /* MQ arithmetic encoder state information. */
    134 
    135 typedef struct {
    136 
    137     /* The A register. */
    138     unsigned areg;
    139 
    140     /* The C register. */
    141     unsigned creg;
    142 
    143     /* The CT register. */
    144     unsigned ctreg;
    145 
    146     /* The last byte output by the encoder. */
    147     int lastbyte;
    148 
    149 } jpc_mqencstate_t;
    150 
    151 /******************************************************************************\
    152 * Functions/macros for construction and destruction.
    153 \******************************************************************************/
    154 
    155 /* Create a MQ encoder. */
    156 jpc_mqenc_t *jpc_mqenc_create(int maxctxs, jas_stream_t *out);
    157 
    158 /* Destroy a MQ encoder. */
    159 void jpc_mqenc_destroy(jpc_mqenc_t *enc);
    160 
    161 /******************************************************************************\
    162 * Functions/macros for initialization.
    163 \******************************************************************************/
    164 
    165 /* Initialize a MQ encoder. */
    166 void jpc_mqenc_init(jpc_mqenc_t *enc);
    167 
    168 /******************************************************************************\
    169 * Functions/macros for context manipulation.
    170 \******************************************************************************/
    171 
    172 /* Set the current context. */
    173 #define	jpc_mqenc_setcurctx(enc, ctxno) \
    174         ((enc)->curctx = &(enc)->ctxs[ctxno]);
    175 
    176 /* Set the state information for a particular context. */
    177 void jpc_mqenc_setctx(jpc_mqenc_t *enc, int ctxno, jpc_mqctx_t *ctx);
    178 
    179 /* Set the state information for multiple contexts. */
    180 void jpc_mqenc_setctxs(jpc_mqenc_t *enc, int numctxs, jpc_mqctx_t *ctxs);
    181 
    182 /******************************************************************************\
    183 * Miscellaneous functions/macros.
    184 \******************************************************************************/
    185 
    186 /* Get the error state of a MQ encoder. */
    187 #define	jpc_mqenc_error(enc) \
    188     ((enc)->err)
    189 
    190 /* Get the current encoder state. */
    191 void jpc_mqenc_getstate(jpc_mqenc_t *enc, jpc_mqencstate_t *state);
    192 
    193 /* Terminate the code. */
    194 int jpc_mqenc_flush(jpc_mqenc_t *enc, int termmode);
    195 
    196 /******************************************************************************\
    197 * Functions/macros for encoding bits.
    198 \******************************************************************************/
    199 
    200 /* Encode a bit. */
    201 #if !defined(DEBUG)
    202 #define	jpc_mqenc_putbit(enc, bit)	jpc_mqenc_putbit_macro(enc, bit)
    203 #else
    204 #define	jpc_mqenc_putbit(enc, bit)	jpc_mqenc_putbit_func(enc, bit)
    205 #endif
    206 
    207 /******************************************************************************\
    208 * Functions/macros for debugging.
    209 \******************************************************************************/
    210 
    211 int jpc_mqenc_dump(jpc_mqenc_t *mqenc, FILE *out);
    212 
    213 /******************************************************************************\
    214 * Implementation-specific details.
    215 \******************************************************************************/
    216 
    217 /* Note: This macro is included only to satisfy the needs of
    218   the mqenc_putbit macro. */
    219 #define	jpc_mqenc_putbit_macro(enc, bit) \
    220     (((*((enc)->curctx))->mps == (bit)) ? \
    221       (((enc)->areg -= (*(enc)->curctx)->qeval), \
    222       ((!((enc)->areg & 0x8000)) ? (jpc_mqenc_codemps2(enc)) : \
    223       ((enc)->creg += (*(enc)->curctx)->qeval))) : \
    224       jpc_mqenc_codelps(enc))
    225 
    226 /* Note: These function prototypes are included only to satisfy the
    227   needs of the mqenc_putbit_macro macro.  Do not call any of these
    228   functions directly. */
    229 int jpc_mqenc_codemps2(jpc_mqenc_t *enc);
    230 int jpc_mqenc_codelps(jpc_mqenc_t *enc);
    231 
    232 /* Note: This function prototype is included only to satisfy the needs of
    233   the mqenc_putbit macro. */
    234 int jpc_mqenc_putbit_func(jpc_mqenc_t *enc, int bit);
    235 
    236 #endif
    237