libbpg/jctvc/TLibCommon/ContextModel.h

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/* The copyright in this software is being made available under the BSD
* License, included below. This software may be subject to other third party
* and contributor rights, including patent rights, and no such rights are
* granted under this license.
*
* Copyright (c) 2010-2014, ITU/ISO/IEC
* All rights reserved.
*
* 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 ITU/ISO/IEC 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 COPYRIGHT HOLDER 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.
*/
/** \file ContextModel.h
\brief context model class (header)
*/
#ifndef __CONTEXTMODEL__
#define __CONTEXTMODEL__
#if _MSC_VER > 1000
#pragma once
#endif // _MSC_VER > 1000
#include "CommonDef.h"
#include "TComRom.h"
//! \ingroup TLibCommon
//! \{
// ====================================================================================================================
// Class definition
// ====================================================================================================================
/// context model class
class ContextModel
{
public:
ContextModel () { m_ucState = 0; m_binsCoded = 0; }
~ContextModel () {}
UChar getState () { return ( m_ucState >> 1 ); } ///< get current state
UChar getMps () { return ( m_ucState & 1 ); } ///< get curret MPS
Void setStateAndMps( UChar ucState, UChar ucMPS) { m_ucState = (ucState << 1) + ucMPS; } ///< set state and MPS
Void init ( Int qp, Int initValue ); ///< initialize state with initial probability
Void updateLPS ()
{
m_ucState = m_aucNextStateLPS[ m_ucState ];
}
Void updateMPS ()
{
m_ucState = m_aucNextStateMPS[ m_ucState ];
}
Int getEntropyBits(Short val) { return m_entropyBits[m_ucState ^ val]; }
#if FAST_BIT_EST
Void update( Int binVal )
{
m_ucState = m_nextState[m_ucState][binVal];
}
static Void buildNextStateTable();
static Int getEntropyBitsTrm( Int val ) { return m_entropyBits[126 ^ val]; }
#endif
Void setBinsCoded(UInt val) { m_binsCoded = val; }
UInt getBinsCoded() { return m_binsCoded; }
private:
UChar m_ucState; ///< internal state variable
static const UInt m_totalStates = (1 << CONTEXT_STATE_BITS) * 2; //*2 for MPS = [0|1]
static const UChar m_aucNextStateMPS[m_totalStates];
static const UChar m_aucNextStateLPS[m_totalStates];
static const Int m_entropyBits [m_totalStates];
#if FAST_BIT_EST
static UChar m_nextState[m_totalStates][2 /*MPS = [0|1]*/];
#endif
UInt m_binsCoded;
};
//! \}
#endif