/** \file     ContextModel.cpp
    \brief    context model class
*/

#include "ContextModel.h"

// ====================================================================================================================
// Public member functions
// ====================================================================================================================

/**
 - initialize context model with respect to QP and initial probability
 .
 \param  iQp         input QP value
 \param  asCtxInit   initial probability table
 */
Void 
ContextModel::init( Int iQp, Short asCtxInit[] )
{
  Int iInitState  = ( ( asCtxInit[ 0 ] * iQp ) >> 4 ) + asCtxInit[ 1 ];
  iInitState      = Min( Max( 1, iInitState ), 126 );
  if( iInitState >= 64 )
  {
    m_ucState     = Min( 62, iInitState - 64 );
    m_ucState    += m_ucState + 1;
  }
  else
  {
    m_ucState     = Min( 62, 63 - iInitState );
    m_ucState    += m_ucState;
  }
}


const UChar 
ContextModel::m_aucNextStateMPS[ 64 ] =
{
  1, 2, 3, 4, 5, 6, 7, 8,   
  9, 10,11,12,13,14,15,16,  
  17,18,19,20,21,22,23,24,
  25,26,27,28,29,30,31,32,  
  33,34,35,36,37,38,39,40,  
  41,42,43,44,45,46,47,48,
  49,50,51,52,53,54,55,56,  
  57,58,59,60,61,62,62,63
};

const UChar 
ContextModel::m_aucNextStateLPS[ 64 ] =
{
  0, 0, 1, 2, 2, 4, 4, 5,   
  6, 7, 8, 9, 9, 11,11,12,  
  13,13,15,15,16,16,18,18,
  19,19,21,21,22,22,23,24,  
  24,25,26,26,27,27,28,29,  
  29,30,30,30,31,32,32,33,
  33,33,34,34,35,35,35,36,  
  36,36,37,37,37,38,38,63
};