CABACWriter.cpp

  }
  bool     codeLast = ( maxSymbol > symbol );
  unsigned bins     = 0;
  unsigned numBins  = 0;
  while( symbol-- )
  {
    bins   <<= 1;
    bins   ++;
    numBins++;
  }
  if( codeLast )
  {
    bins  <<= 1;
    numBins++;
  }
  CHECK(!( numBins <= 32 ), "Unspecified error");
  m_BinEncoder.encodeBinsEP( bins, numBins );
}


void CABACWriter::exp_golomb_eqprob( unsigned symbol, unsigned count )
{
  unsigned bins    = 0;
  unsigned numBins = 0;
  while( symbol >= (unsigned)(1<<count) )
  {
    bins <<= 1;
    bins++;
    numBins++;
    symbol -= 1 << count;
    count++;
  }
  bins <<= 1;
  numBins++;
  bins = (bins << count) | symbol;
  numBins += count;
  CHECK(!( numBins <= 32 ), "Unspecified error");
  m_BinEncoder.encodeBinsEP( bins, numBins );
}

void CABACWriter::codeAlfCtuEnableFlags( CodingStructure& cs, ChannelType channel, AlfSliceParam* alfParam)
{
  if( isLuma( channel ) )
  {
    if (alfParam->enabledFlag[COMPONENT_Y])
      codeAlfCtuEnableFlags( cs, COMPONENT_Y, alfParam );
  }
  else
  {
    if (alfParam->enabledFlag[COMPONENT_Cb])
      codeAlfCtuEnableFlags( cs, COMPONENT_Cb, alfParam );
    if (alfParam->enabledFlag[COMPONENT_Cr])
      codeAlfCtuEnableFlags( cs, COMPONENT_Cr, alfParam );
  }
}
void CABACWriter::codeAlfCtuEnableFlags( CodingStructure& cs, ComponentID compID, AlfSliceParam* alfParam)
{
  uint32_t numCTUs = cs.pcv->sizeInCtus;

  for( int ctuIdx = 0; ctuIdx < numCTUs; ctuIdx++ )
  {
    codeAlfCtuEnableFlag( cs, ctuIdx, compID, alfParam );
  }
}

void CABACWriter::codeAlfCtuEnableFlag( CodingStructure& cs, uint32_t ctuRsAddr, const int compIdx, AlfSliceParam* alfParam)
{
  const bool alfComponentEnabled = (alfParam != NULL) ? alfParam->enabledFlag[compIdx] : cs.slice->getTileGroupAlfEnabledFlag((ComponentID)compIdx);

  if( cs.sps->getALFEnabledFlag() && alfComponentEnabled )
  {
    const PreCalcValues& pcv = *cs.pcv;
    int                 frame_width_in_ctus = pcv.widthInCtus;
    int                 ry = ctuRsAddr / frame_width_in_ctus;
    int                 rx = ctuRsAddr - ry * frame_width_in_ctus;
    const Position      pos( rx * cs.pcv->maxCUWidth, ry * cs.pcv->maxCUHeight );
    const uint32_t          curSliceIdx = cs.slice->getIndependentSliceIdx();
    const uint32_t      curTileIdx = cs.picture->brickMap->getBrickIdxRsMap( pos );
    bool                leftAvail = cs.getCURestricted( pos.offset( -(int)pcv.maxCUWidth, 0 ), pos, curSliceIdx, curTileIdx, CH_L ) ? true : false;
    bool                aboveAvail = cs.getCURestricted( pos.offset( 0, -(int)pcv.maxCUHeight ), pos, curSliceIdx, curTileIdx, CH_L ) ? true : false;

    int leftCTUAddr = leftAvail ? ctuRsAddr - 1 : -1;
    int aboveCTUAddr = aboveAvail ? ctuRsAddr - frame_width_in_ctus : -1;

    uint8_t* ctbAlfFlag = cs.slice->getPic()->getAlfCtuEnableFlag( compIdx );
    int ctx = 0;
    ctx += leftCTUAddr > -1 ? ( ctbAlfFlag[leftCTUAddr] ? 1 : 0 ) : 0;
    ctx += aboveCTUAddr > -1 ? ( ctbAlfFlag[aboveCTUAddr] ? 1 : 0 ) : 0;
    m_BinEncoder.encodeBin( ctbAlfFlag[ctuRsAddr], Ctx::ctbAlfFlag( compIdx * 3 + ctx ) );
  }
}

void CABACWriter::code_unary_fixed( unsigned symbol, unsigned ctxId, unsigned unary_max, unsigned fixed )
{
  bool unary = (symbol <= unary_max);
  m_BinEncoder.encodeBin( unary, ctxId );
  if( unary )
  {
    unary_max_eqprob( symbol, unary_max );
  }
  else
  {
    m_BinEncoder.encodeBinsEP( symbol - unary_max - 1, fixed );
  }
}

void CABACWriter::mip_flag( const CodingUnit& cu )
{
  if( !cu.Y().valid() )
  {
    return;
  }
  if( !cu.cs->sps->getUseMIP() )
  {
    return;
  }
  if( cu.lwidth() > MIP_MAX_WIDTH || cu.lheight() > MIP_MAX_HEIGHT )
  {
    return;
  }
  if( !mipModesAvailable( cu.Y() ) )
  {
    return;
  }

  unsigned ctxId = DeriveCtx::CtxMipFlag( cu );
  m_BinEncoder.encodeBin( cu.mipFlag, Ctx::MipFlag( ctxId ) );
  DTRACE( g_trace_ctx, D_SYNTAX, "mip_flag() pos=(%d,%d) mode=%d\n", cu.lumaPos().x, cu.lumaPos().y, cu.mipFlag ? 1 : 0 );
}

void CABACWriter::mip_pred_modes( const CodingUnit& cu )
{
  if( !cu.Y().valid() )
  {
    return;
  }
  for( const auto &pu : CU::traversePUs( cu ) )
  {
    mip_pred_mode( pu );
  }
}

void CABACWriter::mip_pred_mode( const PredictionUnit& pu )
{
  const int numModes = getNumModesMip( pu.Y() ); CHECKD( numModes > MAX_NUM_MIP_MODE, "Error: too many MIP modes" );

  // derive modeIdx from true MIP mode
  unsigned mpm[NUM_MPM_MIP];
  PU::getMipMPMs(pu, mpm);

  unsigned mipMode = pu.intraDir[CHANNEL_TYPE_LUMA];
  unsigned mpmIdx   = NUM_MPM_MIP;
  for( auto k = 0; k < NUM_MPM_MIP; k++ )
  {
    if( mipMode == mpm[k] )
    {
      mpmIdx = k;
      break;
    }
  }

  unsigned modeIdx;
  if (mpmIdx < NUM_MPM_MIP)
  {
    modeIdx = mpmIdx;
  }
  else
  {
    std::sort( mpm, mpm + NUM_MPM_MIP);

    modeIdx = mipMode;
    for( auto k = (NUM_MPM_MIP - 1); k >= 0; k-- )
    {
      if( modeIdx > mpm[k] )
      {
        modeIdx--;
      }
    }
    CHECK( modeIdx >= (1<<getNumEpBinsMip( pu.Y() )), "Incorrect mode" );
    modeIdx += NUM_MPM_MIP;
  }

  CHECK( modeIdx >= numModes, "modeIdx out of range" );
  int unaryMax = NUM_MPM_MIP - 1;
  int fixedLength = getNumEpBinsMip( pu.Y() );
  code_unary_fixed( modeIdx, Ctx::MipMode( 0 ), unaryMax, fixedLength );

  DTRACE( g_trace_ctx, D_SYNTAX, "mip_pred_mode() pos=(%d,%d) mode=%d\n", pu.lumaPos().x, pu.lumaPos().y, pu.intraDir[CHANNEL_TYPE_LUMA] );
}

void CABACWriter::codeAlfCtuFilterIndex(CodingStructure& cs, uint32_t ctuRsAddr, bool alfEnableLuma)
{
  if ( (!cs.sps->getALFEnabledFlag()) || (!alfEnableLuma))
  {
    return;
  }

  uint8_t* ctbAlfFlag = cs.slice->getPic()->getAlfCtuEnableFlag(COMPONENT_Y);
  if (!ctbAlfFlag[ctuRsAddr])
  {
    return;
  }

  short* alfCtbFilterIndex = cs.slice->getPic()->getAlfCtbFilterIndex();
  const unsigned filterSetIdx = alfCtbFilterIndex[ctuRsAddr];
  unsigned numAps = cs.slice->getTileGroupNumAps();
  unsigned numAvailableFiltSets = numAps + NUM_FIXED_FILTER_SETS;
  if (numAvailableFiltSets > NUM_FIXED_FILTER_SETS)
  {
    int useLatestFilt = (filterSetIdx == NUM_FIXED_FILTER_SETS) ? 1 : 0;
    m_BinEncoder.encodeBin(useLatestFilt, Ctx::AlfUseLatestFilt());
    if (!useLatestFilt)
    {

      if (numAps == 1)
      {
        CHECK(filterSetIdx >= NUM_FIXED_FILTER_SETS, "fixed set numavail < num_fixed");
        xWriteTruncBinCode(filterSetIdx, NUM_FIXED_FILTER_SETS);
      }
      else
      {
        int useTemporalFilt = (filterSetIdx > NUM_FIXED_FILTER_SETS) ? 1 : 0;
        m_BinEncoder.encodeBin(useTemporalFilt, Ctx::AlfUseTemporalFilt());

        if (useTemporalFilt)
        {
          CHECK((filterSetIdx - (NUM_FIXED_FILTER_SETS + 1)) >= (numAvailableFiltSets - (NUM_FIXED_FILTER_SETS + 1)), "temporal non-latest set");
#if JVET_O0247_ALF_CTB_CODING_REDUNDANCY_REMOVAL
          if (numAps > 2)
          {
#endif
            xWriteTruncBinCode(filterSetIdx - (NUM_FIXED_FILTER_SETS + 1), numAvailableFiltSets - (NUM_FIXED_FILTER_SETS + 1));
#if JVET_O0247_ALF_CTB_CODING_REDUNDANCY_REMOVAL
          }
#endif
        }
        else
        {
          CHECK(filterSetIdx >= NUM_FIXED_FILTER_SETS, "fixed set larger than temporal");
          xWriteTruncBinCode(filterSetIdx, NUM_FIXED_FILTER_SETS);
        }
      }
    }
  }
  else
  {
    CHECK(filterSetIdx >= NUM_FIXED_FILTER_SETS, "fixed set numavail < num_fixed");
    xWriteTruncBinCode(filterSetIdx, NUM_FIXED_FILTER_SETS);
  }
}

//! \}