shithub: opus

ref: ec836da27cc2f36435c8dcd7ef57acb26a4d54c6
dir: /libcelt/mfrngcod.h/

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/* (C) 2001-2008 Timothy B. Terriberry
   (C) 2008 Jean-Marc Valin */
/*
   Redistribution and use in source and binary forms, with or without
   modification, are permitted provided that the following conditions
   are met:

   - Redistributions of source code must retain the above copyright
   notice, this list of conditions and the following disclaimer.

   - Redistributions in binary form must reproduce the above copyright
   notice, this list of conditions and the following disclaimer in the
   documentation and/or other materials provided with the distribution.

   - Neither the name of the Xiph.org Foundation nor the names of its
   contributors may be used to endorse or promote products derived from
   this software without specific prior written permission.

   THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
   ``AS IS'' AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
   LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR
   A PARTICULAR PURPOSE ARE DISCLAIMED.  IN NO EVENT SHALL THE FOUNDATION OR
   CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL,
   EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO,
   PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR
   PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF
   LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING
   NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF THIS
   SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
*/

#if !defined(_mfrngcode_H)
# define _mfrngcode_H (1)
# include "entcode.h"

/*Constants used by the entropy encoder/decoder.*/

/*The number of bits to output at a time.*/
# define EC_SYM_BITS   (8)
/*The total number of bits in each of the state registers.*/
# define EC_CODE_BITS  (32)
/*The maximum symbol value.*/
# define EC_SYM_MAX    ((1U<<EC_SYM_BITS)-1)
/*Bits to shift by to move a symbol into the high-order position.*/
# define EC_CODE_SHIFT (EC_CODE_BITS-EC_SYM_BITS-1)
/*Carry bit of the high-order range symbol.*/
# define EC_CODE_TOP   (((ec_uint32)1U)<<EC_CODE_BITS-1)
/*Low-order bit of the high-order range symbol.*/
# define EC_CODE_BOT   (EC_CODE_TOP>>EC_SYM_BITS)
/*Code for which propagating carries are possible.*/
# define EC_CODE_CARRY (((ec_uint32)EC_SYM_MAX)<<EC_CODE_SHIFT)
/*The number of bits available for the last, partial symbol in the code field.*/
# define EC_CODE_EXTRA ((EC_CODE_BITS-2)%EC_SYM_BITS+1)
/*A mask for the bits available in the coding buffer.
  This allows different platforms to use a variable with more bits, if it is
   convenient.
  We will only use EC_CODE_BITS of it.*/
# define EC_CODE_MASK  ((((ec_uint32)1U)<<EC_CODE_BITS-1)-1<<1|1)


/*The non-zero symbol of the second possible reserved ending.
  This must be the high-bit.*/
# define EC_FOF_RSV1      (1<<EC_SYM_BITS-1)
/*A mask for all the other bits.*/
# define EC_FOF_RSV1_MASK (EC_FOF_RSV1-1)

#endif