TDecTop.cpp

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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) 2010-2017, 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.
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 *    this list of conditions and the following disclaimer in the documentation
 *    and/or other materials provided with the distribution.
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 *    be used to endorse or promote products derived from this software without
 *    specific prior written permission.
 *
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 * AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
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 * ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF
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 */

#include "NALread.h"
#include "TDecTop.h"
#include "TDecConformance.h"


TDecTop::TDecTop()
  : m_iMaxRefPicNum(0)
  , m_associatedIRAPType(NAL_UNIT_INVALID)
  , m_pocCRA(0)
  , m_pocRandomAccess(MAX_INT)
  , m_cListPic()
  , m_parameterSetManager()
  , m_apcSlicePilot(NULL)
  , m_SEIs()
  , m_cPrediction()
  , m_cTrQuant()
  , m_cGopDecoder()
  , m_cSliceDecoder()
  , m_cCuDecoder()
  , m_cEntropyDecoder()
  , m_cCavlcDecoder()
  , m_cSbacDecoder()
  , m_cBinCABAC()
  , m_seiReader()
  , m_cLoopFilter()
  , m_cSAO()
  , m_pcPic(NULL)
  , m_prevPOC(MAX_INT)
  , m_prevTid0POC(0)
  , m_bFirstSliceInPicture(true)
  , m_bFirstSliceInSequence(true)
  , m_prevSliceSkipped(false)
  , m_skippedPOC(0)
  , m_bFirstSliceInBitstream(true)
  , m_lastPOCNoOutputPriorPics(-1)
  , m_isNoOutputPriorPics(false)
  , m_craNoRaslOutputFlag(false)
#if O0043_BEST_EFFORT_DECODING
  , m_forceDecodeBitDepth(8)
#endif
  , m_pDecodedSEIOutputStream(NULL)
  , m_warningMessageSkipPicture(false)
#if MCTS_ENC_CHECK
  , m_tmctsCheckEnabled(false)
#endif
  , m_prefixSEINALUs()
{
#if ENC_DEC_TRACE
  if (g_hTrace == NULL)
  {
    g_hTrace = fopen( "TraceDec.txt", "wb" );
  }
  g_bJustDoIt = g_bEncDecTraceDisable;
  g_nSymbolCounter = 0;
#endif
}

TDecTop::~TDecTop()
{
#if ENC_DEC_TRACE
  if (g_hTrace != stdout)
  {
    fclose( g_hTrace );
  }
#endif
  while (!m_prefixSEINALUs.empty())
  {
    delete m_prefixSEINALUs.front();
    m_prefixSEINALUs.pop_front();
  }
}

Void TDecTop::create()
{
  m_cGopDecoder.create();
  m_apcSlicePilot = new TComSlice;
  m_uiSliceIdx = 0;
}

Void TDecTop::destroy()
{
  m_cGopDecoder.destroy();

  delete m_apcSlicePilot;
  m_apcSlicePilot = NULL;

  m_cSliceDecoder.destroy();
}

Void TDecTop::init()
{
  // initialize ROM
  initROM();
  m_cGopDecoder.init( &m_cEntropyDecoder, &m_cSbacDecoder, &m_cBinCABAC, &m_cCavlcDecoder, &m_cSliceDecoder, &m_cLoopFilter, &m_cSAO);
  m_cSliceDecoder.init( &m_cEntropyDecoder, &m_cCuDecoder, &m_conformanceCheck );
#if MCTS_ENC_CHECK
  m_cEntropyDecoder.init(&m_cPrediction, &m_conformanceCheck );
#else
  m_cEntropyDecoder.init(&m_cPrediction);
#endif
}

Void TDecTop::deletePicBuffer ( )
{
  TComList<TComPic*>::iterator  iterPic   = m_cListPic.begin();
  Int iSize = Int( m_cListPic.size() );

  for (Int i = 0; i < iSize; i++ )
  {
    TComPic* pcPic = *(iterPic++);
    pcPic->destroy();

    delete pcPic;
    pcPic = NULL;
  }

  m_cSAO.destroy();

  m_cLoopFilter.        destroy();

  // destroy ROM
  destroyROM();
}

Void TDecTop::xGetNewPicBuffer ( const TComSPS &sps, const TComPPS &pps, TComPic*& rpcPic, const UInt temporalLayer )
{
  m_iMaxRefPicNum = sps.getMaxDecPicBuffering(temporalLayer);     // m_uiMaxDecPicBuffering has the space for the picture currently being decoded
  if (m_cListPic.size() < (UInt)m_iMaxRefPicNum)
  {
    rpcPic = new TComPic();

#if REDUCED_ENCODER_MEMORY
    rpcPic->create ( sps, pps, false, true);
#else
    rpcPic->create ( sps, pps, true);
#endif

    m_cListPic.pushBack( rpcPic );

    return;
  }

  Bool bBufferIsAvailable = false;
  TComList<TComPic*>::iterator  iterPic   = m_cListPic.begin();
  while (iterPic != m_cListPic.end())
  {
    rpcPic = *(iterPic++);
    if ( rpcPic->getReconMark() == false && rpcPic->getOutputMark() == false)
    {
      rpcPic->setOutputMark(false);
      bBufferIsAvailable = true;
      break;
    }

    if ( rpcPic->getSlice( 0 )->isReferenced() == false  && rpcPic->getOutputMark() == false)
    {
      rpcPic->setOutputMark(false);
      rpcPic->setReconMark( false );
      rpcPic->getPicYuvRec()->setBorderExtension( false );
      bBufferIsAvailable = true;
      break;
    }
  }

  if ( !bBufferIsAvailable )
  {
    //There is no room for this picture, either because of faulty encoder or dropped NAL. Extend the buffer.
    m_iMaxRefPicNum++;
    rpcPic = new TComPic();
    m_cListPic.pushBack( rpcPic );
  }
  rpcPic->destroy();
#if REDUCED_ENCODER_MEMORY
  rpcPic->create ( sps, pps, false, true);
#else
  rpcPic->create ( sps, pps, true);
#endif
}

Void TDecTop::executeLoopFilters(Int& poc, TComList<TComPic*>*& rpcListPic)
{
  if (!m_pcPic)
  {
    /* nothing to deblock */
    return;
  }

  TComPic*   pcPic         = m_pcPic;

  // Execute Deblock + Cleanup

  m_cGopDecoder.filterPicture(pcPic);

  TComSlice::sortPicList( m_cListPic ); // sorting for application output
  poc                 = pcPic->getSlice(m_uiSliceIdx-1)->getPOC();
  rpcListPic          = &m_cListPic;
  m_cCuDecoder.destroy();
  m_bFirstSliceInPicture  = true;

  return;
}

Void TDecTop::checkNoOutputPriorPics (TComList<TComPic*>* pcListPic)
{
  if (!pcListPic || !m_isNoOutputPriorPics)
  {
    return;
  }

  TComList<TComPic*>::iterator  iterPic   = pcListPic->begin();

  while (iterPic != pcListPic->end())
  {
    TComPic* pcPicTmp = *(iterPic++);
    if (m_lastPOCNoOutputPriorPics != pcPicTmp->getPOC())
    {
      pcPicTmp->setOutputMark(false);
    }
  }
}

Void TDecTop::xCreateLostPicture(Int iLostPoc)
{
  printf("\ninserting lost poc : %d\n",iLostPoc);
  TComPic *cFillPic;
  xGetNewPicBuffer(*(m_parameterSetManager.getFirstSPS()), *(m_parameterSetManager.getFirstPPS()), cFillPic, 0);
  cFillPic->getSlice(0)->initSlice();

  TComList<TComPic*>::iterator iterPic = m_cListPic.begin();
  Int closestPoc = 1000000;
  while ( iterPic != m_cListPic.end())
  {
    TComPic * rpcPic = *(iterPic++);
    if(abs(rpcPic->getPicSym()->getSlice(0)->getPOC() -iLostPoc)<closestPoc&&abs(rpcPic->getPicSym()->getSlice(0)->getPOC() -iLostPoc)!=0&&rpcPic->getPicSym()->getSlice(0)->getPOC()!=m_apcSlicePilot->getPOC())
    {
      closestPoc=abs(rpcPic->getPicSym()->getSlice(0)->getPOC() -iLostPoc);
    }
  }
  iterPic = m_cListPic.begin();
  while ( iterPic != m_cListPic.end())
  {
    TComPic *rpcPic = *(iterPic++);
    if(abs(rpcPic->getPicSym()->getSlice(0)->getPOC() -iLostPoc)==closestPoc&&rpcPic->getPicSym()->getSlice(0)->getPOC()!=m_apcSlicePilot->getPOC())
    {
      printf("copying picture %d to %d (%d)\n",rpcPic->getPicSym()->getSlice(0)->getPOC() ,iLostPoc,m_apcSlicePilot->getPOC());
      rpcPic->getPicYuvRec()->copyToPic(cFillPic->getPicYuvRec());
      break;
    }
  }
  cFillPic->setCurrSliceIdx(0);
  for(Int ctuRsAddr=0; ctuRsAddr<cFillPic->getNumberOfCtusInFrame(); ctuRsAddr++)
  {
    cFillPic->getCtu(ctuRsAddr)->initCtu(cFillPic, ctuRsAddr);
  }
  cFillPic->getSlice(0)->setReferenced(true);
  cFillPic->getSlice(0)->setPOC(iLostPoc);
  xUpdatePreviousTid0POC(cFillPic->getSlice(0));
  cFillPic->setReconMark(true);
  cFillPic->setOutputMark(true);
  if(m_pocRandomAccess == MAX_INT)
  {
    m_pocRandomAccess = iLostPoc;
  }
}


Void TDecTop::xActivateParameterSets()
{
  if (m_bFirstSliceInPicture)
  {
    const TComPPS *pps = m_parameterSetManager.getPPS(m_apcSlicePilot->getPPSId()); // this is a temporary PPS object. Do not store this value
    assert (pps != 0);

    const TComSPS *sps = m_parameterSetManager.getSPS(pps->getSPSId());             // this is a temporary SPS object. Do not store this value
    assert (sps != 0);

    m_parameterSetManager.clearSPSChangedFlag(sps->getSPSId());
    m_parameterSetManager.clearPPSChangedFlag(pps->getPPSId());

    if (false == m_parameterSetManager.activatePPS(m_apcSlicePilot->getPPSId(),m_apcSlicePilot->isIRAP()))
    {
      printf ("Parameter set activation failed!");
      assert (0);
    }

    xParsePrefixSEImessages();
#if MCTS_ENC_CHECK
    xAnalysePrefixSEImessages();
#endif

#if RExt__HIGH_BIT_DEPTH_SUPPORT==0
    if (sps->getSpsRangeExtension().getExtendedPrecisionProcessingFlag() || sps->getBitDepth(CHANNEL_TYPE_LUMA)>12 || sps->getBitDepth(CHANNEL_TYPE_CHROMA)>12 )
    {
      printf("High bit depth support must be enabled at compile-time in order to decode this bitstream\n");
      assert (0);
      exit(1);
    }
#endif

    // NOTE: globals were set up here originally. You can now use:
    // g_uiMaxCUDepth = sps->getMaxTotalCUDepth();
    // g_uiAddCUDepth = sps->getMaxTotalCUDepth() - sps->getLog2DiffMaxMinCodingBlockSize()

    //  Get a new picture buffer. This will also set up m_pcPic, and therefore give us a SPS and PPS pointer that we can use.
    xGetNewPicBuffer (*(sps), *(pps), m_pcPic, m_apcSlicePilot->getTLayer());
    m_apcSlicePilot->applyReferencePictureSet(m_cListPic, m_apcSlicePilot->getRPS());

    // make the slice-pilot a real slice, and set up the slice-pilot for the next slice
    assert(m_pcPic->getNumAllocatedSlice() == (m_uiSliceIdx + 1));
    m_apcSlicePilot = m_pcPic->getPicSym()->swapSliceObject(m_apcSlicePilot, m_uiSliceIdx);

    // we now have a real slice:
    TComSlice *pSlice = m_pcPic->getSlice(m_uiSliceIdx);

    // Update the PPS and SPS pointers with the ones of the picture.
    pps=pSlice->getPPS();
    sps=pSlice->getSPS();

    // Initialise the various objects for the new set of settings
    m_cSAO.create( sps->getPicWidthInLumaSamples(), sps->getPicHeightInLumaSamples(), sps->getChromaFormatIdc(), sps->getMaxCUWidth(), sps->getMaxCUHeight(), sps->getMaxTotalCUDepth(), pps->getPpsRangeExtension().getLog2SaoOffsetScale(CHANNEL_TYPE_LUMA), pps->getPpsRangeExtension().getLog2SaoOffsetScale(CHANNEL_TYPE_CHROMA) );
    m_cLoopFilter.create( sps->getMaxTotalCUDepth() );
    m_cPrediction.initTempBuff(sps->getChromaFormatIdc());


    Bool isField = false;
    Bool isTopField = false;

    if(!m_SEIs.empty())
    {
      // Check if any new Picture Timing SEI has arrived
      SEIMessages pictureTimingSEIs = getSeisByType(m_SEIs, SEI::PICTURE_TIMING);
      if (pictureTimingSEIs.size()>0)
      {
        SEIPictureTiming* pictureTiming = (SEIPictureTiming*) *(pictureTimingSEIs.begin());
        isField    = (pictureTiming->m_picStruct == 1) || (pictureTiming->m_picStruct == 2) || (pictureTiming->m_picStruct == 9) || (pictureTiming->m_picStruct == 10) || (pictureTiming->m_picStruct == 11) || (pictureTiming->m_picStruct == 12);
        isTopField = (pictureTiming->m_picStruct == 1) || (pictureTiming->m_picStruct == 9) || (pictureTiming->m_picStruct == 11);
      }
    }

    //Set Field/Frame coding mode
    m_pcPic->setField(isField);
    m_pcPic->setTopField(isTopField);

    // transfer any SEI messages that have been received to the picture
    m_pcPic->setSEIs(m_SEIs);
    m_SEIs.clear();

    // Recursive structure
    m_cCuDecoder.create ( sps->getMaxTotalCUDepth(), sps->getMaxCUWidth(), sps->getMaxCUHeight(), sps->getChromaFormatIdc() );
#if MCTS_ENC_CHECK
    m_cCuDecoder.init   ( &m_cEntropyDecoder, &m_cTrQuant, &m_cPrediction, &m_conformanceCheck );
#else
    m_cCuDecoder.init(&m_cEntropyDecoder, &m_cTrQuant, &m_cPrediction);
#endif
    m_cTrQuant.init     ( sps->getMaxTrSize() );

    m_cSliceDecoder.create();
  }
  else
  {
    // make the slice-pilot a real slice, and set up the slice-pilot for the next slice
    m_pcPic->allocateNewSlice();
    assert(m_pcPic->getNumAllocatedSlice() == (m_uiSliceIdx + 1));
    m_apcSlicePilot = m_pcPic->getPicSym()->swapSliceObject(m_apcSlicePilot, m_uiSliceIdx);

    TComSlice *pSlice = m_pcPic->getSlice(m_uiSliceIdx); // we now have a real slice.

    const TComSPS *sps = pSlice->getSPS();
    const TComPPS *pps = pSlice->getPPS();

    // check that the current active PPS has not changed...
    if (m_parameterSetManager.getSPSChangedFlag(sps->getSPSId()) )
    {
      printf("Error - a new SPS has been decoded while processing a picture\n");
      exit(1);
    }
    if (m_parameterSetManager.getPPSChangedFlag(pps->getPPSId()) )
    {
      printf("Error - a new PPS has been decoded while processing a picture\n");
      exit(1);
    }

    xParsePrefixSEImessages();
#if MCTS_ENC_CHECK
    xAnalysePrefixSEImessages();
#endif
    // Check if any new SEI has arrived
     if(!m_SEIs.empty())
     {
       // Currently only decoding Unit SEI message occurring between VCL NALUs copied
       SEIMessages &picSEI = m_pcPic->getSEIs();
       SEIMessages decodingUnitInfos = extractSeisByType (m_SEIs, SEI::DECODING_UNIT_INFO);
       picSEI.insert(picSEI.end(), decodingUnitInfos.begin(), decodingUnitInfos.end());
       deleteSEIs(m_SEIs);
     }
  }
}


Void TDecTop::xParsePrefixSEIsForUnknownVCLNal()
{
  while (!m_prefixSEINALUs.empty())
  {
    // do nothing?
    printf("Discarding Prefix SEI associated with unknown VCL NAL unit.\n");
    delete m_prefixSEINALUs.front();
  }
  // TODO: discard following suffix SEIs as well?
}


Void TDecTop::xParsePrefixSEImessages()
{
  while (!m_prefixSEINALUs.empty())
  {
    InputNALUnit &nalu=*m_prefixSEINALUs.front();
    m_seiReader.parseSEImessage( &(nalu.getBitstream()), m_SEIs, nalu.m_nalUnitType, m_parameterSetManager.getActiveSPS(), m_pDecodedSEIOutputStream );
    delete m_prefixSEINALUs.front();
    m_prefixSEINALUs.pop_front();
  }
}

#if MCTS_ENC_CHECK
Void TDecTop::xAnalysePrefixSEImessages()
{
  if (m_tmctsCheckEnabled)
  {
    SEIMessages mctsSEIs = getSeisByType(m_SEIs, SEI::TEMP_MOTION_CONSTRAINED_TILE_SETS);
    for (SEIMessages::iterator it = mctsSEIs.begin(); it != mctsSEIs.end(); it++)
    {
      SEITempMotionConstrainedTileSets *mcts = (SEITempMotionConstrainedTileSets*)(*it);
      if (!mcts->m_each_tile_one_tile_set_flag)
      {
        printf("cannot (yet) check Temporal constrained MCTS if each_tile_one_tile_set_flag is not enabled\n");
        exit(1);
      }
      else
      {
        printf("MCTS check enabled!\n");
        m_conformanceCheck.enableTMctsCheck(true);
      }
    }
  }
}
#endif

Bool TDecTop::xDecodeSlice(InputNALUnit &nalu, Int &iSkipFrame, Int iPOCLastDisplay )
{
  m_apcSlicePilot->initSlice(); // the slice pilot is an object to prepare for a new slice
                                // it is not associated with picture, sps or pps structures.

  if (m_bFirstSliceInPicture)
  {
    m_uiSliceIdx = 0;
  }
  else
  {
    m_apcSlicePilot->copySliceInfo( m_pcPic->getPicSym()->getSlice(m_uiSliceIdx-1) );
  }
  m_apcSlicePilot->setSliceIdx(m_uiSliceIdx);

  m_apcSlicePilot->setNalUnitType(nalu.m_nalUnitType);
  Bool nonReferenceFlag = (m_apcSlicePilot->getNalUnitType() == NAL_UNIT_CODED_SLICE_TRAIL_N ||
                           m_apcSlicePilot->getNalUnitType() == NAL_UNIT_CODED_SLICE_TSA_N   ||
                           m_apcSlicePilot->getNalUnitType() == NAL_UNIT_CODED_SLICE_STSA_N  ||
                           m_apcSlicePilot->getNalUnitType() == NAL_UNIT_CODED_SLICE_RADL_N  ||
                           m_apcSlicePilot->getNalUnitType() == NAL_UNIT_CODED_SLICE_RASL_N);
  m_apcSlicePilot->setTemporalLayerNonReferenceFlag(nonReferenceFlag);
  m_apcSlicePilot->setReferenced(true); // Putting this as true ensures that picture is referenced the first time it is in an RPS
  m_apcSlicePilot->setTLayerInfo(nalu.m_temporalId);

#if ENC_DEC_TRACE
  const UInt64 originalSymbolCount = g_nSymbolCounter;
#endif

  m_cEntropyDecoder.decodeSliceHeader (m_apcSlicePilot, &m_parameterSetManager, m_prevTid0POC);

  // set POC for dependent slices in skipped pictures
  if(m_apcSlicePilot->getDependentSliceSegmentFlag() && m_prevSliceSkipped)
  {
    m_apcSlicePilot->setPOC(m_skippedPOC);
  }

  xUpdatePreviousTid0POC(m_apcSlicePilot);

  m_apcSlicePilot->setAssociatedIRAPPOC(m_pocCRA);
  m_apcSlicePilot->setAssociatedIRAPType(m_associatedIRAPType);

  //For inference of NoOutputOfPriorPicsFlag
  if (m_apcSlicePilot->getRapPicFlag())
  {
    if ((m_apcSlicePilot->getNalUnitType() >= NAL_UNIT_CODED_SLICE_BLA_W_LP && m_apcSlicePilot->getNalUnitType() <= NAL_UNIT_CODED_SLICE_IDR_N_LP) || 
        (m_apcSlicePilot->getNalUnitType() == NAL_UNIT_CODED_SLICE_CRA && m_bFirstSliceInSequence) ||
        (m_apcSlicePilot->getNalUnitType() == NAL_UNIT_CODED_SLICE_CRA && m_apcSlicePilot->getHandleCraAsBlaFlag()))
    {
      m_apcSlicePilot->setNoRaslOutputFlag(true);
    }
    //the inference for NoOutputPriorPicsFlag
    if (!m_bFirstSliceInBitstream && m_apcSlicePilot->getRapPicFlag() && m_apcSlicePilot->getNoRaslOutputFlag())
    {
      if (m_apcSlicePilot->getNalUnitType() == NAL_UNIT_CODED_SLICE_CRA)
      {
        m_apcSlicePilot->setNoOutputPriorPicsFlag(true);
      }
    }
    else
    {
      m_apcSlicePilot->setNoOutputPriorPicsFlag(false);
    }

    if(m_apcSlicePilot->getNalUnitType() == NAL_UNIT_CODED_SLICE_CRA)
    {
      m_craNoRaslOutputFlag = m_apcSlicePilot->getNoRaslOutputFlag();
    }
  }
  if (m_apcSlicePilot->getRapPicFlag() && m_apcSlicePilot->getNoOutputPriorPicsFlag())
  {
    m_lastPOCNoOutputPriorPics = m_apcSlicePilot->getPOC();
    m_isNoOutputPriorPics = true;
  }
  else
  {
    m_isNoOutputPriorPics = false;
  }

  //For inference of PicOutputFlag
  if (m_apcSlicePilot->getNalUnitType() == NAL_UNIT_CODED_SLICE_RASL_N || m_apcSlicePilot->getNalUnitType() == NAL_UNIT_CODED_SLICE_RASL_R)
  {
    if ( m_craNoRaslOutputFlag )
    {
      m_apcSlicePilot->setPicOutputFlag(false);
    }
  }

  if (m_apcSlicePilot->getNalUnitType() == NAL_UNIT_CODED_SLICE_CRA && m_craNoRaslOutputFlag) //Reset POC MSB when CRA has NoRaslOutputFlag equal to 1
  {
    TComPPS *pps = m_parameterSetManager.getPPS(m_apcSlicePilot->getPPSId());
    assert (pps != 0);
    TComSPS *sps = m_parameterSetManager.getSPS(pps->getSPSId());
    assert (sps != 0);
    Int iMaxPOClsb = 1 << sps->getBitsForPOC();
    m_apcSlicePilot->setPOC( m_apcSlicePilot->getPOC() & (iMaxPOClsb - 1) );
    xUpdatePreviousTid0POC(m_apcSlicePilot);
  }

  // Skip pictures due to random access

  if (isRandomAccessSkipPicture(iSkipFrame, iPOCLastDisplay))
  {
    m_prevSliceSkipped = true;
    m_skippedPOC = m_apcSlicePilot->getPOC();
    return false;
  }
  // Skip TFD pictures associated with BLA/BLANT pictures
  if (isSkipPictureForBLA(iPOCLastDisplay))
  {
    m_prevSliceSkipped = true;
    m_skippedPOC = m_apcSlicePilot->getPOC();
    return false;
  }

  // clear previous slice skipped flag
  m_prevSliceSkipped = false;

  //we should only get a different poc for a new picture (with CTU address==0)
  if (!m_apcSlicePilot->getDependentSliceSegmentFlag() && m_apcSlicePilot->getPOC()!=m_prevPOC && !m_bFirstSliceInSequence && (m_apcSlicePilot->getSliceCurStartCtuTsAddr() != 0))
  {
    printf ("Warning, the first slice of a picture might have been lost!\n");
  }

  // exit when a new picture is found
  if (!m_apcSlicePilot->getDependentSliceSegmentFlag() && (m_apcSlicePilot->getSliceCurStartCtuTsAddr() == 0 && !m_bFirstSliceInPicture) )
  {
    if (m_prevPOC >= m_pocRandomAccess)
    {
      m_prevPOC = m_apcSlicePilot->getPOC();
#if ENC_DEC_TRACE
      //rewind the trace counter since we didn't actually decode the slice
      g_nSymbolCounter = originalSymbolCount;
#endif
      return true;
    }
    m_prevPOC = m_apcSlicePilot->getPOC();
  }

  //detect lost reference picture and insert copy of earlier frame.
  {
    Int lostPoc;
    while((lostPoc=m_apcSlicePilot->checkThatAllRefPicsAreAvailable(m_cListPic, m_apcSlicePilot->getRPS(), true, m_pocRandomAccess)) > 0)
    {
      xCreateLostPicture(lostPoc-1);
    }
  }

  if (!m_apcSlicePilot->getDependentSliceSegmentFlag())
  {
    m_prevPOC = m_apcSlicePilot->getPOC();
  }

  // actual decoding starts here
  xActivateParameterSets();


  TComSlice* pcSlice = m_pcPic->getPicSym()->getSlice(m_uiSliceIdx);

  if (TDecConformanceCheck::doChecking())
  {
    m_conformanceCheck.checkSliceActivation(*pcSlice, nalu, *m_pcPic, m_bFirstSliceInBitstream, m_bFirstSliceInSequence, m_bFirstSliceInPicture);
  }

  m_bFirstSliceInSequence = false;
  m_bFirstSliceInBitstream  = false;

  // When decoding the slice header, the stored start and end addresses were actually RS addresses, not TS addresses.
  // Now, having set up the maps, convert them to the correct form.
  pcSlice->setSliceSegmentCurStartCtuTsAddr( m_pcPic->getPicSym()->getCtuRsToTsAddrMap(pcSlice->getSliceSegmentCurStartCtuTsAddr()) );
  pcSlice->setSliceSegmentCurEndCtuTsAddr( m_pcPic->getPicSym()->getCtuRsToTsAddrMap(pcSlice->getSliceSegmentCurEndCtuTsAddr()) );
  if(!pcSlice->getDependentSliceSegmentFlag())
  {
    pcSlice->setSliceCurStartCtuTsAddr(m_pcPic->getPicSym()->getCtuRsToTsAddrMap(pcSlice->getSliceCurStartCtuTsAddr()));
    pcSlice->setSliceCurEndCtuTsAddr(m_pcPic->getPicSym()->getCtuRsToTsAddrMap(pcSlice->getSliceCurEndCtuTsAddr()));
  }

  m_pcPic->setTLayer(nalu.m_temporalId);

  if (!pcSlice->getDependentSliceSegmentFlag())
  {
    pcSlice->checkCRA(pcSlice->getRPS(), m_pocCRA, m_associatedIRAPType, m_cListPic );
    // Set reference list
    pcSlice->setRefPicList( m_cListPic, true );

    // For generalized B
    // note: maybe not existed case (always L0 is copied to L1 if L1 is empty)
    if (pcSlice->isInterB() && pcSlice->getNumRefIdx(REF_PIC_LIST_1) == 0)
    {
      Int iNumRefIdx = pcSlice->getNumRefIdx(REF_PIC_LIST_0);
      pcSlice->setNumRefIdx        ( REF_PIC_LIST_1, iNumRefIdx );

      for (Int iRefIdx = 0; iRefIdx < iNumRefIdx; iRefIdx++)
      {
        pcSlice->setRefPic(pcSlice->getRefPic(REF_PIC_LIST_0, iRefIdx), REF_PIC_LIST_1, iRefIdx);
      }
    }
    if (!pcSlice->isIntra())
    {
      Bool bLowDelay = true;
      Int  iCurrPOC  = pcSlice->getPOC();
      Int iRefIdx = 0;

      for (iRefIdx = 0; iRefIdx < pcSlice->getNumRefIdx(REF_PIC_LIST_0) && bLowDelay; iRefIdx++)
      {
        if ( pcSlice->getRefPic(REF_PIC_LIST_0, iRefIdx)->getPOC() > iCurrPOC )
        {
          bLowDelay = false;
        }
      }
      if (pcSlice->isInterB())
      {
        for (iRefIdx = 0; iRefIdx < pcSlice->getNumRefIdx(REF_PIC_LIST_1) && bLowDelay; iRefIdx++)
        {
          if ( pcSlice->getRefPic(REF_PIC_LIST_1, iRefIdx)->getPOC() > iCurrPOC )
          {
            bLowDelay = false;
          }
        }
      }

      pcSlice->setCheckLDC(bLowDelay);
    }

    //---------------
    pcSlice->setRefPOCList();
  }

  m_pcPic->setCurrSliceIdx(m_uiSliceIdx);
  if(pcSlice->getSPS()->getScalingListFlag())
  {
    TComScalingList scalingList;
    if(pcSlice->getPPS()->getScalingListPresentFlag())
    {
      scalingList = pcSlice->getPPS()->getScalingList();
    }
    else if (pcSlice->getSPS()->getScalingListPresentFlag())
    {
      scalingList = pcSlice->getSPS()->getScalingList();
    }
    else
    {
      scalingList.setDefaultScalingList();
    }
    m_cTrQuant.setScalingListDec(scalingList);
    m_cTrQuant.setUseScalingList(true);
  }
  else
  {
    const Int maxLog2TrDynamicRange[MAX_NUM_CHANNEL_TYPE] =
    {
        pcSlice->getSPS()->getMaxLog2TrDynamicRange(CHANNEL_TYPE_LUMA),
        pcSlice->getSPS()->getMaxLog2TrDynamicRange(CHANNEL_TYPE_CHROMA)
    };
    m_cTrQuant.setFlatScalingList(maxLog2TrDynamicRange, pcSlice->getSPS()->getBitDepths());
    m_cTrQuant.setUseScalingList(false);
  }

  //  Decode a picture
  m_cGopDecoder.decompressSlice(&(nalu.getBitstream()), m_pcPic);

  m_bFirstSliceInPicture = false;
  m_uiSliceIdx++;

  return false;
}

Void TDecTop::xDecodeVPS(const std::vector<UChar> &naluData)
{
  TComVPS* vps = new TComVPS();

  m_cEntropyDecoder.decodeVPS( vps );
  m_parameterSetManager.storeVPS(vps, naluData);
}

Void TDecTop::xDecodeSPS(const std::vector<UChar> &naluData)
{
  TComSPS* sps = new TComSPS();
#if O0043_BEST_EFFORT_DECODING
  sps->setForceDecodeBitDepth(m_forceDecodeBitDepth);
#endif
  m_cEntropyDecoder.decodeSPS( sps );
  m_parameterSetManager.storeSPS(sps, naluData);
}

Void TDecTop::xDecodePPS(const std::vector<UChar> &naluData)
{
  TComPPS* pps = new TComPPS();
  m_cEntropyDecoder.decodePPS( pps );
  m_parameterSetManager.storePPS( pps, naluData);
}

Bool TDecTop::decode(InputNALUnit& nalu, Int& iSkipFrame, Int& iPOCLastDisplay)
{
  // ignore all NAL units of layers > 0
  if (nalu.m_nuhLayerId > 0)
  {
    fprintf (stderr, "Warning: found NAL unit with nuh_layer_id equal to %d. Ignoring.\n", nalu.m_nuhLayerId);
    return false;
  }
  // Initialize entropy decoder
  m_cEntropyDecoder.setEntropyDecoder (&m_cCavlcDecoder);
  m_cEntropyDecoder.setBitstream      (&(nalu.getBitstream()));

  switch (nalu.m_nalUnitType)
  {
    case NAL_UNIT_VPS:
      xDecodeVPS(nalu.getBitstream().getFifo());
      return false;

    case NAL_UNIT_SPS:
      xDecodeSPS(nalu.getBitstream().getFifo());
      return false;

    case NAL_UNIT_PPS:
      xDecodePPS(nalu.getBitstream().getFifo());
      return false;

    case NAL_UNIT_PREFIX_SEI:
      // Buffer up prefix SEI messages until SPS of associated VCL is known.
      m_prefixSEINALUs.push_back(new InputNALUnit(nalu));
      return false;

    case NAL_UNIT_SUFFIX_SEI:
      if (m_pcPic)
      {
        m_seiReader.parseSEImessage( &(nalu.getBitstream()), m_pcPic->getSEIs(), nalu.m_nalUnitType, m_parameterSetManager.getActiveSPS(), m_pDecodedSEIOutputStream );
      }
      else
      {
        printf ("Note: received suffix SEI but no picture currently active.\n");
      }
      return false;

    case NAL_UNIT_CODED_SLICE_TRAIL_R:
    case NAL_UNIT_CODED_SLICE_TRAIL_N:
    case NAL_UNIT_CODED_SLICE_TSA_R:
    case NAL_UNIT_CODED_SLICE_TSA_N:
    case NAL_UNIT_CODED_SLICE_STSA_R:
    case NAL_UNIT_CODED_SLICE_STSA_N:
    case NAL_UNIT_CODED_SLICE_BLA_W_LP:
    case NAL_UNIT_CODED_SLICE_BLA_W_RADL:
    case NAL_UNIT_CODED_SLICE_BLA_N_LP:
    case NAL_UNIT_CODED_SLICE_IDR_W_RADL:
    case NAL_UNIT_CODED_SLICE_IDR_N_LP:
    case NAL_UNIT_CODED_SLICE_CRA:
    case NAL_UNIT_CODED_SLICE_RADL_N:
    case NAL_UNIT_CODED_SLICE_RADL_R:
    case NAL_UNIT_CODED_SLICE_RASL_N:
    case NAL_UNIT_CODED_SLICE_RASL_R:
      return xDecodeSlice(nalu, iSkipFrame, iPOCLastDisplay);
      break;

    case NAL_UNIT_EOS:
      m_associatedIRAPType = NAL_UNIT_INVALID;
      m_pocCRA = 0;
      m_pocRandomAccess = MAX_INT;
      m_prevPOC = MAX_INT;
      m_prevSliceSkipped = false;
      m_skippedPOC = 0;
      return false;

    case NAL_UNIT_ACCESS_UNIT_DELIMITER:
      {
        AUDReader audReader;
        UInt picType;
        audReader.parseAccessUnitDelimiter(&(nalu.getBitstream()),picType);
        printf ("Note: found NAL_UNIT_ACCESS_UNIT_DELIMITER\n");
        return false;
      }

    case NAL_UNIT_EOB:
      return false;

    case NAL_UNIT_FILLER_DATA:
      {
        FDReader fdReader;
        UInt size;
        fdReader.parseFillerData(&(nalu.getBitstream()),size);
        printf ("Note: found NAL_UNIT_FILLER_DATA with %u bytes payload.\n", size);
        return false;
      }

    case NAL_UNIT_RESERVED_VCL_N10:
    case NAL_UNIT_RESERVED_VCL_R11:
    case NAL_UNIT_RESERVED_VCL_N12:
    case NAL_UNIT_RESERVED_VCL_R13:
    case NAL_UNIT_RESERVED_VCL_N14:
    case NAL_UNIT_RESERVED_VCL_R15:

    case NAL_UNIT_RESERVED_IRAP_VCL22:
    case NAL_UNIT_RESERVED_IRAP_VCL23:

    case NAL_UNIT_RESERVED_VCL24:
    case NAL_UNIT_RESERVED_VCL25:
    case NAL_UNIT_RESERVED_VCL26:
    case NAL_UNIT_RESERVED_VCL27:
    case NAL_UNIT_RESERVED_VCL28:
    case NAL_UNIT_RESERVED_VCL29:
    case NAL_UNIT_RESERVED_VCL30:
    case NAL_UNIT_RESERVED_VCL31:
      printf ("Note: found reserved VCL NAL unit.\n");
      xParsePrefixSEIsForUnknownVCLNal();
      return false;

    case NAL_UNIT_RESERVED_NVCL41:
    case NAL_UNIT_RESERVED_NVCL42:
    case NAL_UNIT_RESERVED_NVCL43:
    case NAL_UNIT_RESERVED_NVCL44:
    case NAL_UNIT_RESERVED_NVCL45:
    case NAL_UNIT_RESERVED_NVCL46:
    case NAL_UNIT_RESERVED_NVCL47:
      printf ("Note: found reserved NAL unit.\n");
      return false;
    case NAL_UNIT_UNSPECIFIED_48:
    case NAL_UNIT_UNSPECIFIED_49:
    case NAL_UNIT_UNSPECIFIED_50:
    case NAL_UNIT_UNSPECIFIED_51:
    case NAL_UNIT_UNSPECIFIED_52:
    case NAL_UNIT_UNSPECIFIED_53:
    case NAL_UNIT_UNSPECIFIED_54:
    case NAL_UNIT_UNSPECIFIED_55:
    case NAL_UNIT_UNSPECIFIED_56:
    case NAL_UNIT_UNSPECIFIED_57:
    case NAL_UNIT_UNSPECIFIED_58:
    case NAL_UNIT_UNSPECIFIED_59:
    case NAL_UNIT_UNSPECIFIED_60:
    case NAL_UNIT_UNSPECIFIED_61:
    case NAL_UNIT_UNSPECIFIED_62:
    case NAL_UNIT_UNSPECIFIED_63:
      printf ("Note: found unspecified NAL unit.\n");
      return false;
    default:
      assert (0);
      break;
  }

  return false;
}

Bool TDecTop::isSkipPictureForBLA(Int& iPOCLastDisplay)
{
  if ((m_associatedIRAPType == NAL_UNIT_CODED_SLICE_BLA_N_LP || m_associatedIRAPType == NAL_UNIT_CODED_SLICE_BLA_W_LP || m_associatedIRAPType == NAL_UNIT_CODED_SLICE_BLA_W_RADL) &&
       m_apcSlicePilot->getPOC() < m_pocCRA && (m_apcSlicePilot->getNalUnitType() == NAL_UNIT_CODED_SLICE_RASL_R || m_apcSlicePilot->getNalUnitType() == NAL_UNIT_CODED_SLICE_RASL_N))
  {
    iPOCLastDisplay++;
    return true;
  }
  return false;
}

Bool TDecTop::isRandomAccessSkipPicture(Int& iSkipFrame,  Int& iPOCLastDisplay)
{
  if (iSkipFrame)
  {
    iSkipFrame--;   // decrement the counter
    return true;
  }
  else if (m_pocRandomAccess == MAX_INT) // start of random access point, m_pocRandomAccess has not been set yet.
  {
    if (   m_apcSlicePilot->getNalUnitType() == NAL_UNIT_CODED_SLICE_CRA
        || m_apcSlicePilot->getNalUnitType() == NAL_UNIT_CODED_SLICE_BLA_W_LP
        || m_apcSlicePilot->getNalUnitType() == NAL_UNIT_CODED_SLICE_BLA_N_LP
        || m_apcSlicePilot->getNalUnitType() == NAL_UNIT_CODED_SLICE_BLA_W_RADL )
    {
      // set the POC random access since we need to skip the reordered pictures in the case of CRA/CRANT/BLA/BLANT.
      m_pocRandomAccess = m_apcSlicePilot->getPOC();
    }
    else if ( m_apcSlicePilot->getNalUnitType() == NAL_UNIT_CODED_SLICE_IDR_W_RADL || m_apcSlicePilot->getNalUnitType() == NAL_UNIT_CODED_SLICE_IDR_N_LP )
    {
      m_pocRandomAccess = -MAX_INT; // no need to skip the reordered pictures in IDR, they are decodable.
    }
    else
    {
      if(!m_warningMessageSkipPicture)
      {
        printf("\nWarning: this is not a valid random access point and the data is discarded until the first CRA picture");
        m_warningMessageSkipPicture = true;
      }
      return true;
    }
  }
  // skip the reordered pictures, if necessary
  else if (m_apcSlicePilot->getPOC() < m_pocRandomAccess && (m_apcSlicePilot->getNalUnitType() == NAL_UNIT_CODED_SLICE_RASL_R || m_apcSlicePilot->getNalUnitType() == NAL_UNIT_CODED_SLICE_RASL_N))
  {
    iPOCLastDisplay++;
    return true;
  }
  // if we reach here, then the picture is not skipped.
  return false;
}