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Diffstat (limited to 'gs/jasper/src/libjasper/jpc/jpc_mqdec.h')
| -rw-r--r-- | gs/jasper/src/libjasper/jpc/jpc_mqdec.h | 260 |
1 files changed, 260 insertions, 0 deletions
diff --git a/gs/jasper/src/libjasper/jpc/jpc_mqdec.h b/gs/jasper/src/libjasper/jpc/jpc_mqdec.h new file mode 100644 index 000000000..d0ee84b9d --- /dev/null +++ b/gs/jasper/src/libjasper/jpc/jpc_mqdec.h @@ -0,0 +1,260 @@ +/* + * 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) 1999-2000 Image Power, Inc. + * Copyright (c) 1999-2000 The University of British Columbia + * Copyright (c) 2001-2003 Michael David Adams + * + * 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_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. */ +#define jpc_mqdec_getbit(dec) \ + jpc_mqdec_getbit_macro(dec) + +/* Decode a symbol (assuming an unskewed probability distribution). */ +#define jpc_mqdec_getbitnoskew(dec) \ + jpc_mqdec_getbit_macro(dec) + +/******************************************************************************\ +* 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_mpsexchrenormd(jpc_mqdec_t *dec); +int jpc_mqdec_lpsexchrenormd(jpc_mqdec_t *dec); + +#endif |