mbc_s.h

/**
    Copyright (C) powturbo 2013-2022
    GPL v3 License

    This program is free software; you can redistribute it and/or modify
    it under the terms of the GNU General Public License as published by
    the Free Software Foundation; either version 3 of the License, or
    (at your option) any later version.

    This program is distributed in the hope that it will be useful,
    but WITHOUT ANY WARRANTY; without even the implied warranty of
    MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
    GNU General Public License for more details.

    You should have received a copy of the GNU General Public License along
    with this program; if not, write to the Free Software Foundation, Inc.,
    51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA.

    - homepage : https://sites.google.com/site/powturbo/
    - github   : https://github.com/powturbo
    - twitter  : https://twitter.com/powturbo
    - email    : powturbo [_AT_] gmail [_DOT_] com
**/
// TurboRC: Range Coder - simple predictor (16 bits counter)
#define RC_PRDID 1
#define RC_PRD   s

  #ifdef RC_MACROS
#define mbu unsigned short
#define mbu_p(_mb_,_prm0_) (*(_mb_))
  #else
typedef unsigned short mbu;
static inline int mbu_p(mbu *mb, int _prm0_) { return (*mb); } // get probability 
  #endif

#define mbu_probinit()      (1<<(RC_BITS-1))       // initial probability 0.5
#define mbu_init(_m_, _p0_) { *(_m_) = _p0_; }     // predictor init

  #ifdef RATE_S // rate (=_prm0_) as parameter
#define RCPRM  //,unsigned RCPRM0
#define RCPRMC //,RCPRM0
#define mbu_update( _mb_, _mbp_, _prm0_, _prm1_, _bit_) *(_mb_) = (_mbp_) - ((((_mbp_) - (-_bit_ & (1<<RC_BITS))) >> _prm0_) + _bit_)
#define mbu_update0(_mb_, _mbp_, _prm0_, _prm1_) mbu_update( _mb_, _mbp_, _prm0_, _prm1_, 0)
#define mbu_update1(_mb_, _mbp_, _prm0_, _prm1_) mbu_update( _mb_, _mbp_, _prm0_, _prm1_, 1)
  #else
#define RCPRM
#define RCPRMC
    #if 0
#define mbu_update1(_mb_, _mbp_, _prm0_, _prm1_) (*(_mb_) = (_mbp_) + (((1u<<RC_BITS)- (_mbp_)) >> 5))  // Predictor update for bit 0
#define mbu_update0(_mb_, _mbp_, _prm0_, _prm1_) (*(_mb_) = (_mbp_) - ((_mbp_) >> 5))                   // Predictor update for bit 1
#define mbu_update( _mb_, _mbp_, _prm0_, _prm1_, _bit_) (_bit_)?mbu_update1(_mb_, _mbp_, _prm0_, _prm1_):mbu_update0(_mb_, _mbp_, _prm0_, _prm1_)
    #else
#define mbu_update0(_mb_, _mbp_, _prm0_, _prm1_)        *(_mb_) = (_mbp_) - ((_mbp_) >> 5)
#define mbu_update1(_mb_, _mbp_, _prm0_, _prm1_)        *(_mb_) = (_mbp_) - ( (((_mbp_) - (1<<RC_BITS)) >> 5) + 1)
#define mbu_update( _mb_, _mbp_, _prm0_, _prm1_, _bit_) *(_mb_) = (_mbp_) - ((((_mbp_) - (-_bit_ & (1<<RC_BITS))) >> 5) + _bit_)
    #endif
  #endif

#include "mbc.h"