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/** \file     PreProcess.cpp

    \brief    

*/

#include "PreProcess.h"

#include "BitAllocation.h"

//! \ingroup EncoderLib

//! \{

namespace vvenc {

PreProcess::PreProcess( MsgLog& _m )

  : m_encCfg     ( nullptr )

  , m_gopCfg     ( _m )

  , m_lastPoc    ( 0 )

  , m_isHighRes  ( false )

  , m_doSTA      ( false )

  , m_doTempDown ( false )

  , m_doVisAct   ( false )

  , m_doVisActQpa( false )

  , m_cappedCQF  ( false )

{

}

PreProcess::~PreProcess()

{

}

void PreProcess::init( const VVEncCfg& encCfg, bool isFinalPass )

{

  m_gopCfg.initGopList( encCfg.m_DecodingRefreshType, encCfg.m_poc0idr, encCfg.m_IntraPeriod, encCfg.m_GOPSize, encCfg.m_leadFrames, encCfg.m_picReordering, encCfg.m_GOPList, encCfg.m_vvencMCTF, encCfg.m_FirstPassMode, encCfg.m_minIntraDist );

  CHECK( m_gopCfg.getMaxTLayer() != encCfg.m_maxTLayer, "max temporal layer of gop configuration does not match pre-configured value" );

  m_encCfg             = &encCfg;

  m_lastPoc            = std::numeric_limits<int>::min();

  m_isHighRes          = (std::min (m_encCfg->m_SourceWidth, m_encCfg->m_SourceHeight) > 1280);

  m_doSTA              = m_encCfg->m_sliceTypeAdapt > 0;

  m_cappedCQF          = m_encCfg->m_RCNumPasses != 2 && m_encCfg->m_rateCap;

  m_doTempDown         = m_encCfg->m_FirstPassMode == 2 || m_encCfg->m_FirstPassMode == 4;

  m_doVisAct           = m_encCfg->m_usePerceptQPA

                         || (m_encCfg->m_LookAhead && m_encCfg->m_RCTargetBitrate > 0)

                         || (m_encCfg->m_RCNumPasses > 1 && (!isFinalPass));

  m_doVisActQpa        = m_encCfg->m_usePerceptQPA;

}

void PreProcess::initPicture( Picture* pic )

{

}

void PreProcess::processPictures( const PicList& picList, AccessUnitList& auList, PicList& doneList, PicList& freeList )

{

  // continue with next poc

  if( ! picList.empty() && picList.back()->poc > m_lastPoc )

  {

    auto pic = picList.back();

    // set gop entry

    m_gopCfg.getNextGopEntry( pic->m_picShared->m_gopEntry );

    CHECK( pic->m_picShared->m_gopEntry.m_POC != pic->poc, "invalid state" );

    if( ! pic->m_picShared->isLeadTrail() )

    {

      // link previous frames

      xLinkPrevQpaBufs( pic, picList );

      // compute visual activity

      xGetVisualActivity( pic, picList );

      // detect scc

      xDetectScc( pic );

      // scene cuts, where the film grain parameters switch

      if( m_encCfg->m_fga )

      {

        xDetectFgaSceneCut( pic );

      }

      // slice type adaptation

      if( m_doSTA && pic->gopEntry->m_temporalId == 0 )

      {

        // detect scene cut in gop and adapt slice type

        xDetectSTA( pic, picList );

        // disable temporal downsampling for gop with scene cut

        if( m_doTempDown && pic->gopEntry->m_scType == SCT_TL0_SCENE_CUT )

        {

          xDisableTempDown( pic, picList );

        }

      }

      // disable temporal downsampling in lowest 3 temp. layers

      // with one-pass RC and QPA; this stabilizes the RC a bit

      if( m_doTempDown && m_doVisActQpa && pic->gopEntry->m_temporalId <= 2 && m_encCfg->m_LookAhead && m_encCfg->m_RCTargetBitrate > 0 )

      {

        xDisableTempDown( pic, picList, 0 /*for faster - TODO: 2 for fast*/ );

      }

    }

    else if( pic->gopEntry->m_temporalId == 0 )

    {

      xGetVisualActivity( pic, picList );

    }

    // cleanup pic list

    xFreeUnused( pic, picList, doneList, freeList );

    m_lastPoc = picList.back()->poc;

  }

  else if( ! picList.empty() && picList.back()->isFlush  )

  {

    // first flush call, fix start of last gop

    if( ! picList.empty() )

    {

      Picture* pic = xGetStartOfLastGop( picList );

      if( pic )

      {

        m_gopCfg.fixStartOfLastGop( pic->m_picShared->m_gopEntry );

        // compute visual activity for start of last GOP

        // this works in combination with xUpdateVAStartOfLastGop()

        xGetVisualActivity( pic, picList );

      }

    }

    // cleanup when flush is set and all pics are done

    for( auto pic : picList )

    {

      freeList.push_back( pic );

    }

  }

}

void PreProcess::xFreeUnused( Picture* pic, const PicList& picList, PicList& doneList, PicList& freeList ) const

{

  // current picture is done

  doneList.push_back( pic );

  // free unused previous frames

  bool foundTl0       = ! m_doSTA; // is sta is off, not need to keep previous tl0 pic

  int idx             = 0;

  Picture* startOfGop = xGetStartOfLastGop( picList );

  for( auto itr = picList.rbegin(); itr != picList.rend(); itr++, idx++ )

  {

    Picture* tp  = *itr;

    bool keepPic = false;

    // keep previous frames for visual activity

    keepPic  |= ( m_doVisAct || m_cappedCQF || m_encCfg->m_GOPQPA ) && idx < NUM_QPA_PREV_FRAMES;

    // keep previous (first) tl0 pic for sta

    keepPic  |= ! foundTl0 && ( tp->gopEntry->m_temporalId == 0 || m_doTempDown );

    foundTl0 |=                 tp->gopEntry->m_temporalId == 0;  // update found tl0

    // keep start of last gop

    keepPic  |= ( tp == startOfGop );

    if( ! keepPic )

    {

      freeList.push_back( tp );

    }

  }

}

void PreProcess::xGetPrevPics( const Picture* pic, const PicList& picList, const Picture* prevPics[ NUM_QPA_PREV_FRAMES ] ) const

{

  std::fill_n( prevPics, NUM_QPA_PREV_FRAMES, nullptr );

  // find previous pics

  int prevPoc = pic->poc;

  int prevIdx = 0;

  for( auto itr = picList.rbegin(); itr != picList.rend() && prevIdx < NUM_QPA_PREV_FRAMES; itr++ )

  {

    Picture* tp = *itr;

    if( tp->poc >= pic->poc )

      continue;

    if( tp->poc != prevPoc - 1 )

      break;

    prevPics[ prevIdx ] = tp;

    prevPoc -= 1;

    prevIdx += 1;

  }

  // if first prev not found, set link to picture itself

  if( prevPics[ 0 ] == nullptr )

  {

    prevPics[ 0 ] = pic;

  }

}

Picture* PreProcess::xGetPrevTL0Pic( const Picture* pic, const PicList& picList ) const

{

  // find previous tl0 picture

  Picture* prevTL0 = nullptr;

  for( auto itr = picList.rbegin(); itr != picList.rend(); itr++ )

  {

    Picture* tp = *itr;

    if( tp == pic )

      continue;

    if( tp->gopEntry->m_temporalId == 0 )

    {

      prevTL0 = tp;

      break;

    }

  }

  return prevTL0;

}

Picture* PreProcess::xGetStartOfLastGop( const PicList& picList ) const

{

  // use only non lead trail pics

  std::vector<Picture*> cnList;

  cnList.reserve( picList.size() );

  for( auto pic : picList )

  {

    if( ! pic->m_picShared->isLeadTrail() )

    {

      cnList.push_back( pic );

    }

  }

  if( cnList.empty() )

  {

    return nullptr;

  }

  // sort pics by coding number

  std::sort( cnList.begin(), cnList.end(), []( auto& a, auto& b ){ return a->gopEntry->m_codingNum < b->gopEntry->m_codingNum; } );

  // find start of current gop

  Picture* pic = cnList.back();

  const int poc0Offset = (m_encCfg->m_poc0idr ? -1 : 0); // place leading poc 0 idr in GOP -1

  const int lastGopNum = pic->gopEntry->m_gopNum + (pic->gopEntry->m_POC == 0 ? poc0Offset : 0);

  for( auto itr = cnList.rbegin(); itr != cnList.rend(); itr++ )

  {

    Picture* tp = *itr;

    const int tpGopNum = tp->gopEntry->m_gopNum + (tp->gopEntry->m_POC == 0 ? poc0Offset : 0);

    if( tpGopNum != lastGopNum )

    {

      return pic;

    }

    pic = tp;

  }

  return pic;

}

void PreProcess::xLinkPrevQpaBufs( Picture* pic, const PicList& picList ) const

{

  PicShared* picShared = pic->m_picShared;

  // find max previous pictures

  if( m_doVisAct )

  {

    const Picture* prevPics[ NUM_QPA_PREV_FRAMES ];

    xGetPrevPics( pic, picList, prevPics );

    for( int i = 0; i < NUM_QPA_PREV_FRAMES; i++ )

    {

      if( prevPics[ i ] )

      {

        picShared->m_prevShared[ i ] = prevPics[ i ]->m_picShared;

      }

    }

  }

}

void PreProcess::xGetVisualActivity( Picture* pic, const PicList& picList ) const

{

  VisAct va[ MAX_NUM_CH ];

  VisAct vaTL0;

  const bool doChroma           = m_cappedCQF && pic->gopEntry->m_isStartOfGop && isChromaEnabled( pic->chromaFormat );

  // for the time being qpa activity done on ctu basis in applyQPAdaptationSlice(), which for now sums up luma activity

  const bool doVisAct           = m_doVisAct && !m_doVisActQpa;

  const bool doSpatAct          = pic->gopEntry->m_isStartOfGop && m_encCfg->m_GOPQPA;

  const bool doVisActStartOfGOP = pic->gopEntry->m_isStartOfGop && m_cappedCQF;

  const bool doVisActTL0        = pic->gopEntry->m_temporalId == 0 && ( m_doSTA || m_cappedCQF || !doVisAct );

  // spatial activity

  if( doSpatAct || doVisAct || doVisActStartOfGOP || doVisActTL0 )

  {

    xGetSpatialActivity( pic, true, doChroma, va );

    // copy luma spatial activity for prev TL0

    if( doVisActTL0 )

    {

      vaTL0 = va[ CH_L ];

    }

  }

  // visual activity to previous pics (luma only)

  if( doVisAct || doVisActStartOfGOP )

  {

    // get temporal activity for picture

    const Picture* prevPics[ NUM_QPA_PREV_FRAMES ];

    xGetPrevPics( pic, picList, prevPics );

    xGetTemporalActivity( pic, prevPics[ 0 ], prevPics[ 1 ], va[ CH_L ] );

    // visual activity for picture

    updateVisAct( va[ CH_L ], m_encCfg->m_internalBitDepth[ CH_L ] );

  }

  // visual activity to previous TL0 pic (luma only)

  const Picture* prevTL0 = xGetPrevTL0Pic( pic, picList );

  if( doVisActTL0 && prevTL0 )

  {

    // get temporal activity for picture

    xGetTemporalActivity( pic, prevTL0, nullptr, vaTL0 );

    // visual activity for picture

    updateVisAct( vaTL0, m_encCfg->m_internalBitDepth[ CH_L ] );

  }

  // store visual activity

  PicShared* picShared               = pic->m_picShared;

  picShared->m_picVA.spatAct[ CH_L ] = ClipBD( (uint16_t)va[ CH_L ].spatAct, 12 );

  picShared->m_picVA.spatAct[ CH_C ] = ClipBD( (uint16_t)va[ CH_C ].spatAct, 12 );

  picShared->m_picVA.visAct          = va[ CH_L ].visAct;

  picShared->m_picVA.visActTL0       = vaTL0.visAct;

  if( prevTL0 )

  {

    picShared->m_picVA.prevTL0spatAct[ CH_L ] = prevTL0->m_picShared->m_picVA.spatAct[ CH_L ];

    picShared->m_picVA.prevTL0spatAct[ CH_C ] = prevTL0->m_picShared->m_picVA.spatAct[ CH_C ];

  }

  // update visual activity in pic, this is needed for STA detection in this stage

  pic->picVA = picShared->m_picVA;

}

void PreProcess::xGetSpatialActivity( Picture* pic, bool doLuma, bool doChroma, VisAct va[ MAX_NUM_CH ] ) const

{

  // luma part

  if( doLuma )

  {

    const int bitDepth = m_encCfg->m_internalBitDepth[ CH_L ];

    CPelBuf origBuf    = pic->getOrigBuf( COMP_Y );

    calcSpatialVisAct( origBuf.buf, origBuf.stride, origBuf.height, origBuf.width, bitDepth, m_isHighRes, va[ CH_L ] );

  }

  // chroma part

  if( doChroma )

  {

    const int bitDepth = m_encCfg->m_internalBitDepth[ CH_C ];

    const bool isUHD   = m_isHighRes && ( pic->chromaFormat == CHROMA_444 );

    const int numComp  = getNumberValidComponents( pic->chromaFormat );

    // accumulate spatial activity over chroma components

    for( int comp = 1; comp < numComp; comp++ )

    {

      VisAct chVA;

      const ComponentID compID = (ComponentID) comp;

      CPelBuf origBuf          = pic->getOrigBuf( compID );

      calcSpatialVisAct( origBuf.buf, origBuf.stride, origBuf.height, origBuf.width, bitDepth, isUHD, chVA );

      va[ CH_C ].hpSpatAct += chVA.hpSpatAct;

    }

    // mean value over chroma components

    va[ CH_C ].hpSpatAct = va[ CH_C ].hpSpatAct / (double)( numComp - 1 );

    // spatial in 12 bit

    va[ CH_C ].spatAct   = unsigned (0.5 + va[ CH_C ].hpSpatAct * double (bitDepth < 12 ? 1 << (12 - bitDepth) : 1));

  }

}

void PreProcess::xGetTemporalActivity( Picture* curPic, const Picture* refPic1, const Picture* refPic2, VisAct& va ) const

{

  CHECK( curPic == nullptr || refPic1 == nullptr, "no pictures given to compute visual activity" );

  const int bitDepth = m_encCfg->m_internalBitDepth[ CH_L ];

  CPelBuf origBufs[ 3 ];

  origBufs[ 0 ] = curPic->getOrigBuf( COMP_Y );

  origBufs[ 1 ] = refPic1->getOrigBuf( COMP_Y );

  if( refPic2 )

  {

    origBufs[ 2 ] = refPic2->getOrigBuf( COMP_Y );

  }

  calcTemporalVisAct( origBufs[0].buf, origBufs[0].stride, origBufs[0].height, origBufs[0].width,

                      origBufs[1].buf, origBufs[1].stride,

                      origBufs[2].buf, origBufs[2].stride,

                      m_encCfg->m_FrameRate / m_encCfg->m_FrameScale,

                      bitDepth,

                      m_isHighRes,

                      va

                    );

}

void PreProcess::xDetectSTA( Picture* pic, const PicList& picList )

{

  const Picture* prevTL0 = xGetPrevTL0Pic( pic, picList );

  int picMemorySTA  = 0;

  bool isSta        = false;

  bool intraAllowed = m_gopCfg.isSTAallowed( pic->poc );

  if( prevTL0 && prevTL0->picVA.visActTL0 > 0 && intraAllowed )

  {

    const int scThreshold = ( ( pic->isSccStrong ? 6 : ( pic->isSccWeak ? 5 : 4 ) ) * ( m_isHighRes ? 19 : 15 ) ) >> 2;

    if(        pic->picVA.visActTL0 * 11 > prevTL0->picVA.visActTL0 * scThreshold

        || prevTL0->picVA.visActTL0 * 11 > pic->picVA.visActTL0     * ( scThreshold + 1 ) )

    {

      const int dir = pic->picVA.visActTL0 < prevTL0->picVA.visActTL0 ? -1 : 1;

      picMemorySTA  = prevTL0->picVA.visActTL0 * dir;

      isSta         = ( picMemorySTA * prevTL0->picMemorySTA ) >= 0;

    }

  }

  if( isSta )

  {

    PicShared* picShared              = pic->m_picShared;

    pic->picMemorySTA                 = picMemorySTA;

    picShared->m_picMemorySTA         = picMemorySTA;

    picShared->m_gopEntry.m_sliceType = 'I';

    picShared->m_gopEntry.m_scType    = SCT_TL0_SCENE_CUT;

    m_gopCfg.setLastIntraSTA( pic->poc );

    if( m_encCfg->m_sliceTypeAdapt == 2 )

    {

      m_gopCfg.startIntraPeriod( picShared->m_gopEntry );

    }

  }

}

// A picture starts a new scene when its luma histogram (64 bins, every 4th sample of every 4th row) differs from that

// of the picture before it by more than 0.3 (L1 distance of the normalized histograms, 0 to 2) and the next picture's

// stays within a quarter of that of it, so that a single flash frame is no cut. On three minutes of The Beekeeper (4316

// pictures) the distance is 0.014 at the median; the 41 cuts found are the same from thresholds 0.15 to 0.3, and

// no GOP of 32 pictures has two of them. The cut is marked on the picture once the next one is processed, and every

// picture carries the latest cut found before it, so that the film grain analysis of a GOP's first coded picture knows

// the cuts among the pictures it covers.

void PreProcess::xDetectFgaSceneCut( Picture* pic )

{

  const CPelBuf y     = pic->getOrigBuf( COMP_Y );

  const int     shift = std::max( 0, m_encCfg->m_internalBitDepth[ CH_L ] - 6 );

  std::vector<int> hist( FGA_HIST_BINS, 0 );

  int numSamples = 0;

  for( int row = 0; row < (int) y.height; row += 4 )

  {

    const Pel* src = y.bufAt( 0, row );

    for( int x = 0; x < (int) y.width; x += 4, numSamples++ )

    {

      hist[ std::min( FGA_HIST_BINS - 1, std::max( 0, src[ x ] >> shift ) ) ]++;

    }

  }

  const bool follows  = pic->poc == m_fgaPrevPoc + 1;

  int        distance = 0;   // in samples: the L1 distance times numSamples

  for( int b = 0; follows && b < FGA_HIST_BINS; b++ )

  {

    distance += std::abs( hist[ b ] - m_fgaPrevHist[ b ] );

  }

  // the previous picture is a cut when it jumped from its predecessor (above 0.3) and this one stays (below 0.075)

  if( follows && m_fgaPrevShared && m_fgaPrevDistance * 10 > 3 * numSamples && distance * 40 < 3 * numSamples )

  {

    m_fgaPrevShared->fgaSceneCut() = true;

    m_fgaLastCutPoc                = m_fgaPrevPoc;

  }

  pic->m_picShared->fgaLastSceneCutPoc() = m_fgaLastCutPoc;

  m_fgaPrevHist     = std::move( hist );

  m_fgaPrevPoc      = pic->poc;

  m_fgaPrevDistance = follows ? distance : 0;

  m_fgaPrevShared   = pic->m_picShared;

}

void PreProcess::xDisableTempDown( Picture* pic, const PicList& picList, const int thresh /*= INT32_MAX*/ )

{

  for( auto itr = picList.rbegin(); itr != picList.rend(); itr++ )

  {

    Picture* tp = *itr;

    if( pic->gopEntry->m_gopNum != tp->gopEntry->m_gopNum )

      break;

    if( tp->gopEntry->m_temporalId <= thresh )

      tp->m_picShared->m_gopEntry.m_skipFirstPass = false;

  }

}

#if FIX_FOR_TEMPORARY_COMPILER_ISSUES_ENABLED && defined( __GNUC__ ) && __GNUC__ == 5

#pragma GCC diagnostic push

#pragma GCC diagnostic ignored "-Wstrict-overflow"

#endif

void PreProcess::xDetectScc( Picture* pic ) const

{

  if( m_encCfg->m_forceScc > 0 )

  {

    pic->isSccStrong = pic->m_picShared->m_isSccStrong = m_encCfg->m_forceScc >= 3;

    pic->isSccWeak   = pic->m_picShared->m_isSccWeak   = m_encCfg->m_forceScc >= 2;

    return;

  }

  CPelBuf yuvOrgBuf = pic->getOrigBuf().Y();

  // blocksize and threshold

  static constexpr int SIZE_BL =  4;

  static constexpr int K_SC    = 23;

  static constexpr int K_noSC  =  8;

  // mean and variance fixed point accuracy

  static constexpr int accM = 4;

  static constexpr int accV = 2;

  static_assert( accM <= 4 && accV <= 4, "Maximum Mean and Variance accuracy of 4 allowed!" );

  static constexpr int shfM = 4 - accM;

  static constexpr int shfV = 4 + accM - accV;

  static constexpr int addM = 1 << shfM >> 1;

  static constexpr int addV = 1 << shfV >> 1;

  static constexpr int SizeS = SIZE_BL << 1;

  const int minLevel = 1 << ( m_encCfg->m_internalBitDepth[CH_L] - ( m_encCfg->m_videoFullRangeFlag ? 6 : 4 ) ); // 1/16th or 1/64th of range

  const Pel*     piSrc    = yuvOrgBuf.buf;

  const uint32_t uiStride = yuvOrgBuf.stride;

  const uint32_t uiWidth  = yuvOrgBuf.width;

  const uint32_t uiHeight = yuvOrgBuf.height;

  CHECK( ( uiWidth & 7 ) != 0 || ( uiHeight & 7 ) != 0, "Width and height have to be multiples of 8!" );

  const int amountBlock = ( uiWidth >> 2 ) * ( uiHeight >> 2 );

  int sR[4] = { 0, 0, 0, 0 }; // strong SCC data

  int zR[4] = { 0, 0, 0, 0 }; // zero input data

  // sums and absolute deviations of the 4x4 blocks of the two block rows of an 8x8 block row

  static_assert( SIZE_BL == 4 && accM == 4, "blockStats4x4 computes 4x4 block sums and deviations from 16 * sample" );

  const int numBlocks = uiWidth / SIZE_BL;

  std::vector<int> blkSum[2] = { std::vector<int>( numBlocks ), std::vector<int>( numBlocks ) };

  std::vector<int> blkDev[2] = { std::vector<int>( numBlocks ), std::vector<int>( numBlocks ) };

  const int bitDepth = m_encCfg->m_internalBitDepth[CH_L];

  for( int hh = 0; hh < uiHeight; hh += SizeS )

  {

    for( int r = 0; r < 2; r++ )

    {

      g_pelBufOP.blockStats4x4( &piSrc[( hh + r * SIZE_BL ) * uiStride], uiStride, numBlocks, bitDepth, blkSum[r].data(), blkDev[r].data() );

    }

    for( int ww = 0; ww < uiWidth; ww += SizeS )

    {

      int Rx = ww >= ( uiWidth  >> 1 ) ? 1 : 0;

      int Ry = hh >= ( uiHeight >> 1 ) ? 2 : 0;

      Ry = Ry | Rx;

      int n = 0;

      int Var[4];

      for( int j = 0; j < 2; j++ )

      {

        for( int i = ( ww / SIZE_BL ); i < ( ww / SIZE_BL ) + 2; i++ )

        {

          const int Mit = ( blkSum[j][i] + addM ) >> shfM;

          const int V   = blkDev[j][i];

          // if variance is lower than 1 and mean is lower/equal to minLevel

          if( V < ( 1 << ( accM + 4 ) ) && Mit <= ( minLevel << accM ) )

          {

            Var[n] = -1;

          }

          else

          {

            Var[n] = ( V + addV ) >> shfV;

          }

          n++;

        }

      }

      for( int i = 0; i < 2; i++ )

      {

        const int var0 = Var[ i];

        const int var1 = Var[ i + 2];

        const int var2 = Var[ i << 1];

        const int var3 = Var[(i << 1) + 1];

        if( var0 < 0 && var1 < 0 && zR[Ry] * 20 < amountBlock )

        {

          zR[Ry]++;

        }

        else if( var0 == var1 )

        {

          sR[Ry]++;

        }

        if( var2 < 0 && var3 < 0 && zR[Ry] * 20 < amountBlock )

        {

          zR[Ry]++;

        }

        else if( var2 == var3 )

        {

          sR[Ry]++;

        }

      }

    }

  }

  bool isSccWeak     = false;

  bool isSccStrong   = false;

  bool isNoSccStrong = false;

  int numAll   = 0;

  int numMin   = amountBlock, numMax = 0;

  int numBelow = 0;

  for( int r = 0; r < 4; r++ )

  {

    numAll   += sR[r];

    numMax    = std::max( numMax, sR[r] );

    numMin    = std::min( numMin, sR[r] );

    numBelow += sR[r] * 100 <= K_SC * ( amountBlock >> 2 ) ? 1 : 0;

  }

  // lowest quarter is above K_SC threshold

  isSccStrong   = numMin * 100 >  K_SC *   ( amountBlock >> 2 );

  // lowest quarter is below K_noSC threshold and theres more than one quarter below K_SC threshold

  isNoSccStrong = numMin * 100 <= K_noSC * ( amountBlock >> 2 ) && numBelow > 1;

  // overall is above K_SC threshold

  isSccWeak     = numAll * 100 >  K_SC *     amountBlock;

  // peak quarter is above 2.15*K_SC threshold

  isSccStrong  |= isSccWeak && !isNoSccStrong && numMax * 186 > K_SC * amountBlock;

  PicShared* picShared     = pic->m_picShared;

  pic->isSccWeak           = isSccWeak;

  pic->isSccStrong         = isSccStrong;

  picShared->m_isSccWeak   = isSccWeak;

  picShared->m_isSccStrong = isSccStrong;

}

#if FIX_FOR_TEMPORARY_COMPILER_ISSUES_ENABLED && defined( __GNUC__ ) && __GNUC__ == 5

#pragma GCC diagnostic pop

#endif

} // namespace vvenc

//! \}