2 * The copyright in this software is being made available under the 2-clauses
3 * BSD License, included below. This software may be subject to other third
4 * party and contributor rights, including patent rights, and no such rights
5 * are granted under this license.
7 * Copyright (c) 2002-2014, Universite catholique de Louvain (UCL), Belgium
8 * Copyright (c) 2002-2014, Professor Benoit Macq
9 * Copyright (c) 2001-2003, David Janssens
10 * Copyright (c) 2002-2003, Yannick Verschueren
11 * Copyright (c) 2003-2007, Francois-Olivier Devaux
12 * Copyright (c) 2003-2014, Antonin Descampe
13 * Copyright (c) 2005, Herve Drolon, FreeImage Team
14 * Copyright (c) 2008, Jerome Fimes, Communications & Systemes <jerome.fimes@c-s.fr>
15 * All rights reserved.
17 * Redistribution and use in source and binary forms, with or without
18 * modification, are permitted provided that the following conditions
20 * 1. Redistributions of source code must retain the above copyright
21 * notice, this list of conditions and the following disclaimer.
22 * 2. Redistributions in binary form must reproduce the above copyright
23 * notice, this list of conditions and the following disclaimer in the
24 * documentation and/or other materials provided with the distribution.
26 * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS `AS IS'
27 * AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
28 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
29 * ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT OWNER OR CONTRIBUTORS BE
30 * LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR
31 * CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF
32 * SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS
33 * INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN
34 * CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE)
35 * ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE
36 * POSSIBILITY OF SUCH DAMAGE.
42 #include "opj_common.h"
46 @brief Implementation of an MQ-Coder (MQC)
48 The functions in MQC.C have for goal to realize the MQ-coder operations. The functions
49 in MQC.C are used by some function in T1.C.
52 /** @defgroup MQC MQC - Implementation of an MQ-Coder */
56 This struct defines the state of a context.
58 typedef struct opj_mqc_state {
59 /** the probability of the Least Probable Symbol (0.75->0x8000, 1.5->0xffff) */
61 /** the Most Probable Symbol (0 or 1) */
63 /** next state if the next encoded symbol is the MPS */
64 struct opj_mqc_state *nmps;
65 /** next state if the next encoded symbol is the LPS */
66 struct opj_mqc_state *nlps;
69 #define MQC_NUMCTXS 19
74 typedef struct opj_mqc {
75 /** temporary buffer where bits are coded or decoded */
77 /** only used by MQ decoder */
79 /** number of bits already read or free to write */
81 /** pointer to the current position in the buffer */
83 /** pointer to the start of the buffer */
85 /** pointer to the end of the buffer */
87 /** Array of contexts */
88 opj_mqc_state_t *ctxs[MQC_NUMCTXS];
90 opj_mqc_state_t **curctx;
91 /* lut_ctxno_zc shifted by (1 << 9) * bandno */
92 const OPJ_BYTE* lut_ctxno_zc_orient;
93 /** Original value of the 2 bytes at end[0] and end[1] */
94 OPJ_BYTE backup[OPJ_COMMON_CBLK_DATA_EXTRA];
99 /** @name Exported functions */
101 /* ----------------------------------------------------------------------- */
104 Return the number of bytes written/read since initialisation
105 @param mqc MQC handle
106 @return Returns the number of bytes already encoded
108 OPJ_UINT32 opj_mqc_numbytes(opj_mqc_t *mqc);
110 Reset the states of all the context of the coder/decoder
111 (each context is set to a state where 0 and 1 are more or less equiprobable)
112 @param mqc MQC handle
114 void opj_mqc_resetstates(opj_mqc_t *mqc);
116 Set the state of a particular context
117 @param mqc MQC handle
118 @param ctxno Number that identifies the context
119 @param msb The MSB of the new state of the context
120 @param prob Number that identifies the probability of the symbols for the new state of the context
122 void opj_mqc_setstate(opj_mqc_t *mqc, OPJ_UINT32 ctxno, OPJ_UINT32 msb,
125 Initialize the encoder
126 @param mqc MQC handle
127 @param bp Pointer to the start of the buffer where the bytes will be written
129 void opj_mqc_init_enc(opj_mqc_t *mqc, OPJ_BYTE *bp);
131 Set the current context used for coding/decoding
132 @param mqc MQC handle
133 @param ctxno Number that identifies the context
135 #define opj_mqc_setcurctx(mqc, ctxno) (mqc)->curctx = &(mqc)->ctxs[(OPJ_UINT32)(ctxno)]
137 Encode a symbol using the MQ-coder
138 @param mqc MQC handle
139 @param d The symbol to be encoded (0 or 1)
141 void opj_mqc_encode(opj_mqc_t *mqc, OPJ_UINT32 d);
143 Flush the encoder, so that all remaining data is written
144 @param mqc MQC handle
146 void opj_mqc_flush(opj_mqc_t *mqc);
148 BYPASS mode switch, initialization operation.
150 @param mqc MQC handle
152 void opj_mqc_bypass_init_enc(opj_mqc_t *mqc);
154 /** Return number of extra bytes to add to opj_mqc_numbytes() for theĀ²
155 size of a non-terminating BYPASS pass
156 @param mqc MQC handle
157 @param erterm 1 if ERTERM is enabled, 0 otherwise
159 OPJ_UINT32 opj_mqc_bypass_get_extra_bytes(opj_mqc_t *mqc, OPJ_BOOL erterm);
162 BYPASS mode switch, coding operation.
164 @param mqc MQC handle
165 @param d The symbol to be encoded (0 or 1)
167 void opj_mqc_bypass_enc(opj_mqc_t *mqc, OPJ_UINT32 d);
169 BYPASS mode switch, flush operation
170 @param mqc MQC handle
171 @param erterm 1 if ERTERM is enabled, 0 otherwise
173 void opj_mqc_bypass_flush_enc(opj_mqc_t *mqc, OPJ_BOOL erterm);
176 @param mqc MQC handle
178 void opj_mqc_reset_enc(opj_mqc_t *mqc);
182 RESTART mode switch (TERMALL)
183 @param mqc MQC handle
184 @return Returns 1 (always)
186 OPJ_UINT32 opj_mqc_restart_enc(opj_mqc_t *mqc);
190 RESTART mode switch (TERMALL) reinitialisation
191 @param mqc MQC handle
193 void opj_mqc_restart_init_enc(opj_mqc_t *mqc);
195 ERTERM mode switch (PTERM)
196 @param mqc MQC handle
198 void opj_mqc_erterm_enc(opj_mqc_t *mqc);
200 SEGMARK mode switch (SEGSYM)
201 @param mqc MQC handle
203 void opj_mqc_segmark_enc(opj_mqc_t *mqc);
206 Initialize the decoder for MQ decoding.
208 opj_mqc_finish_dec() must be absolutely called after finishing the decoding
209 passes, so as to restore the bytes temporarily overwritten.
211 @param mqc MQC handle
212 @param bp Pointer to the start of the buffer from which the bytes will be read
213 Note that OPJ_COMMON_CBLK_DATA_EXTRA bytes at the end of the buffer
214 will be temporarily overwritten with an artificial 0xFF 0xFF marker.
215 (they will be backuped in the mqc structure to be restored later)
216 So bp must be at least len + OPJ_COMMON_CBLK_DATA_EXTRA large, and
218 @param len Length of the input buffer
219 @param extra_writable_bytes Indicate how many bytes after len are writable.
220 This is to indicate your consent that bp must be
223 void opj_mqc_init_dec(opj_mqc_t *mqc, OPJ_BYTE *bp, OPJ_UINT32 len,
224 OPJ_UINT32 extra_writable_bytes);
227 Initialize the decoder for RAW decoding.
229 opj_mqc_finish_dec() must be absolutely called after finishing the decoding
230 passes, so as to restore the bytes temporarily overwritten.
232 @param mqc MQC handle
233 @param bp Pointer to the start of the buffer from which the bytes will be read
234 Note that OPJ_COMMON_CBLK_DATA_EXTRA bytes at the end of the buffer
235 will be temporarily overwritten with an artificial 0xFF 0xFF marker.
236 (they will be backuped in the mqc structure to be restored later)
237 So bp must be at least len + OPJ_COMMON_CBLK_DATA_EXTRA large, and
239 @param len Length of the input buffer
240 @param extra_writable_bytes Indicate how many bytes after len are writable.
241 This is to indicate your consent that bp must be
244 void opj_mqc_raw_init_dec(opj_mqc_t *mqc, OPJ_BYTE *bp, OPJ_UINT32 len,
245 OPJ_UINT32 extra_writable_bytes);
249 Terminate RAW/MQC decoding
251 This restores the bytes temporarily overwritten by opj_mqc_init_dec()/
252 opj_mqc_raw_init_dec()
254 @param mqc MQC handle
256 void opq_mqc_finish_dec(opj_mqc_t *mqc);
260 @param mqc MQC handle
261 @return Returns the decoded symbol (0 or 1)
263 /*static INLINE OPJ_UINT32 opj_mqc_decode(opj_mqc_t * const mqc);*/
264 /* ----------------------------------------------------------------------- */