M4Global.h

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// Copyright Epic Games, Inc. All Rights Reserved.
#pragma once
 
#include "vdecmpeg4_Types.h"
 
namespace vdecmpeg4
{
 
// --------------------------------------------------------------------------------
 
enum M4_MBMODE
{
    M4_MBMODE_INTER             = 0,
    M4_MBMODE_INTER_Q           = 1,
    M4_MBMODE_INTER4V           = 2,
    M4_MBMODE_INTRA             = 3,
    M4_MBMODE_INTRA_Q           = 4,
    M4_MBMODE_STUFFING          = 7,
    M4_MBMODE_NOT_CODED_PVOP    = 16,
    M4_MBMODE_NOT_CODED_SVOP    = 17
};
 
enum M4_MBFLAGS
{
    M4_MBFLAG_MVTYPE_DIRECT          = 0,       // 00
    M4_MBFLAG_MVTYPE_INTERPOLATE     = 1,       // 01
    M4_MBFLAG_MVTYPE_BACKWARD        = 2,       // 10
    M4_MBFLAG_MVTYPE_FORWARD         = 3,       // 11
    M4_MBFLAG_MVTYPE_MASK            = 0x03,
 
    M4_MBFLAG_FIELD_DCT_BIT          = 0x04,
    M4_MBFLAG_FIELD_PREDICTION_BIT   = 0x08,
 
    M4_MBFLAG_FIELD_REF_FWD_MASK     = 0x30,    // we use 2 bits storing the latest ref_field_top/bottom
    M4_MBFLAG_HAS_MOTION_VECTOR      = 0x80
};
 
#ifndef M4MAX
#define M4MAX(A,B)      ((A)>(B)?(A):(B))
#endif
 
#ifndef M4MIN
#define M4MIN(A,B)      ((A)<(B)?(A):(B))
#endif
 
#define M4_MBPRED_SIZE  15
 
 
 
struct M4BitstreamCacheEntry
{
/*  4*/ uint32  mState;                     
/* 12*/ uint16  mDcScaler[6];               
/*768*/ int16   mDctFromBitstream[6*64];    
};
 
enum MV_PREDICTION
{
    MV_PREDICTION_NONE,
    MV_PREDICTION_P_FORWARD,
    MV_PREDICTION_B_FORWARD,
    MV_PREDICTION_B_BACKWARD
};
 
struct M4_VECTOR
{
    int32 x;
    int32 y;
};
 
 
// ------------------------------------------------------------------------------
// Macroblock structure
//
// There a sizeof check somewhere - dont enlarge this struct too much
//
// Currently, it 256 bytes. Having a 1920x1088p frame means
//
//  !!  120 macroblocks per row x 68 rows = 8160 macroblocks !!
//  !!  and this yields around 2 MB of macroblock only data  !!
// ------------------------------------------------------------------------------
 
struct M4_MB
{
    uint8           mMode      : 7;                                 // 0
    uint8           mModeIntra : 1;
 
    uint8           mQuant      : 5;                                // 1
    uint8           mMvResidual : 1;
    uint8           _free       : 2;
 
    uint8           mACPredDirections[6];                           // 2 + 6
    M4_VECTOR       mFMv[4];        
    int16           mPredictedValues[6][M4_MBPRED_SIZE];            // 40
    uint8           mFlags;
    uint8           mCbp;
    M4_VECTOR       mBMv[4];        
};
 
 
}