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* Copyright (c) 2002-2007, Communications and Remote Sensing Laboratory, Universite catholique de Louvain (UCL), Belgium
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* Copyright (c) 2002-2007, Professor Benoit Macq
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* Copyright (c) 2001-2003, David Janssens
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* Copyright (c) 2002-2003, Yannick Verschueren
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* Copyright (c) 2003-2007, Francois-Olivier Devaux and Antonin Descampe
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* Copyright (c) 2005, Herve Drolon, FreeImage Team
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* Redistribution and use in source and binary forms, with or without
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* modification, are permitted provided that the following conditions
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* 1. Redistributions of source code must retain the above copyright
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* notice, this list of conditions and the following disclaimer.
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* 2. Redistributions in binary form must reproduce the above copyright
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* notice, this list of conditions and the following disclaimer in the
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* documentation and/or other materials provided with the distribution.
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* THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS `AS IS'
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* AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
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* IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
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* ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT OWNER OR CONTRIBUTORS BE
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* LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR
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* CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF
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* SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS
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* INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN
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* CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE)
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* ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE
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* POSSIBILITY OF SUCH DAMAGE.
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@brief Implementation of an MQ-Coder (MQC)
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The functions in MQC.C have for goal to realize the MQ-coder operations. The functions
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in MQC.C are used by some function in T1.C.
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/** @defgroup MQC MQC - Implementation of an MQ-Coder */
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This struct defines the state of a context.
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typedef struct opj_mqc_state {
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/** the probability of the Least Probable Symbol (0.75->0x8000, 1.5->0xffff) */
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/** the Most Probable Symbol (0 or 1) */
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/** next state if the next encoded symbol is the MPS */
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struct opj_mqc_state *nmps;
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/** next state if the next encoded symbol is the LPS */
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struct opj_mqc_state *nlps;
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#define MQC_NUMCTXS 19
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typedef struct opj_mqc {
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opj_mqc_state_t *ctxs[MQC_NUMCTXS];
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opj_mqc_state_t **curctx;
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unsigned char *buffer;
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/** @name Exported functions */
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/* ----------------------------------------------------------------------- */
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Create a new MQC handle
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@return Returns a new MQC handle if successful, returns NULL otherwise
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opj_mqc_t* mqc_create(void);
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Destroy a previously created MQC handle
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@param mqc MQC handle to destroy
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void mqc_destroy(opj_mqc_t *mqc);
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Return the number of bytes written/read since initialisation
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@return Returns the number of bytes already encoded
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int mqc_numbytes(opj_mqc_t *mqc);
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Reset the states of all the context of the coder/decoder
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(each context is set to a state where 0 and 1 are more or less equiprobable)
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@param mqc MQC handle
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void mqc_resetstates(opj_mqc_t *mqc);
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Set the state of a particular context
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@param mqc MQC handle
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@param ctxno Number that identifies the context
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@param msb The MSB of the new state of the context
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@param prob Number that identifies the probability of the symbols for the new state of the context
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void mqc_setstate(opj_mqc_t *mqc, int ctxno, int msb, int prob);
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Initialize the encoder
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@param mqc MQC handle
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@param bp Pointer to the start of the buffer where the bytes will be written
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void mqc_init_enc(opj_mqc_t *mqc, unsigned char *bp);
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Set the current context used for coding/decoding
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@param mqc MQC handle
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@param ctxno Number that identifies the context
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#define mqc_setcurctx(mqc, ctxno) (mqc)->curctx = &(mqc)->ctxs[(int)(ctxno)]
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Encode a symbol using the MQ-coder
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@param mqc MQC handle
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@param d The symbol to be encoded (0 or 1)
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void mqc_encode(opj_mqc_t *mqc, int d);
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Flush the encoder, so that all remaining data is written
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@param mqc MQC handle
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void mqc_flush(opj_mqc_t *mqc);
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BYPASS mode switch, initialization operation.
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<h2>Not fully implemented and tested !!</h2>
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@param mqc MQC handle
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void mqc_bypass_init_enc(opj_mqc_t *mqc);
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BYPASS mode switch, coding operation.
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<h2>Not fully implemented and tested !!</h2>
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@param mqc MQC handle
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@param d The symbol to be encoded (0 or 1)
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void mqc_bypass_enc(opj_mqc_t *mqc, int d);
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BYPASS mode switch, flush operation
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<h2>Not fully implemented and tested !!</h2>
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@param mqc MQC handle
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@return Returns 1 (always)
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int mqc_bypass_flush_enc(opj_mqc_t *mqc);
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@param mqc MQC handle
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void mqc_reset_enc(opj_mqc_t *mqc);
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RESTART mode switch (TERMALL)
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@param mqc MQC handle
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@return Returns 1 (always)
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int mqc_restart_enc(opj_mqc_t *mqc);
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RESTART mode switch (TERMALL) reinitialisation
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@param mqc MQC handle
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void mqc_restart_init_enc(opj_mqc_t *mqc);
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ERTERM mode switch (PTERM)
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@param mqc MQC handle
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void mqc_erterm_enc(opj_mqc_t *mqc);
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SEGMARK mode switch (SEGSYM)
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@param mqc MQC handle
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void mqc_segmark_enc(opj_mqc_t *mqc);
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Initialize the decoder
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@param mqc MQC handle
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@param bp Pointer to the start of the buffer from which the bytes will be read
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@param len Length of the input buffer
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void mqc_init_dec(opj_mqc_t *mqc, unsigned char *bp, int len);
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@param mqc MQC handle
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@return Returns the decoded symbol (0 or 1)
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int mqc_decode(opj_mqc_t *const mqc);
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/* ----------------------------------------------------------------------- */