DecLib.cpp

  // leave when a new picture is found
#if HEVC_DEPENDENT_SLICES
  if (!m_apcSlicePilot->getDependentSliceSegmentFlag() && (m_apcSlicePilot->getSliceCurStartCtuTsAddr() == 0 && !m_bFirstSliceInPicture) )
#else
  if(m_apcSlicePilot->getSliceCurStartCtuTsAddr() == 0 && !m_bFirstSliceInPicture)
#endif
  {
    if (m_prevPOC >= m_pocRandomAccess)
    {
      DTRACE_UPDATE( g_trace_ctx, std::make_pair( "final", 0 ) );
      m_prevPOC = m_apcSlicePilot->getPOC();
      return true;
    }
    m_prevPOC = m_apcSlicePilot->getPOC();
  }
  else
  {
    DTRACE_UPDATE( g_trace_ctx, std::make_pair( "final", 1 ) );
  }

  //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 HEVC_DEPENDENT_SLICES
  if (!m_apcSlicePilot->getDependentSliceSegmentFlag())
  {
#endif
    m_prevPOC = m_apcSlicePilot->getPOC();
#if HEVC_DEPENDENT_SLICES
  }
#endif

  if (m_bFirstSliceInPicture)
  {
    xUpdateRasInit(m_apcSlicePilot);
  }

  // actual decoding starts here
  xActivateParameterSets();

  m_bFirstSliceInSequence = false;
  m_bFirstSliceInBitstream  = false;


  Slice* pcSlice = m_pcPic->slices[m_uiSliceSegmentIdx];
  pcSlice->setPic( m_pcPic );
  m_pcPic->poc         = pcSlice->getPOC();
  m_pcPic->layer       = pcSlice->getTLayer();
  m_pcPic->referenced  = true;
  m_pcPic->layer       = nalu.m_temporalId;

  // 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.
#if HEVC_TILES_WPP
  const TileMap& tileMap = *(m_pcPic->tileMap);
#endif
#if HEVC_DEPENDENT_SLICES
#if HEVC_TILES_WPP
  pcSlice->setSliceSegmentCurStartCtuTsAddr( tileMap.getCtuRsToTsAddrMap(pcSlice->getSliceSegmentCurStartCtuTsAddr()) );
  pcSlice->setSliceSegmentCurEndCtuTsAddr( tileMap.getCtuRsToTsAddrMap(pcSlice->getSliceSegmentCurEndCtuTsAddr()) );
#endif
  if(!pcSlice->getDependentSliceSegmentFlag())
  {
#endif
#if HEVC_TILES_WPP
    pcSlice->setSliceCurStartCtuTsAddr( tileMap.getCtuRsToTsAddrMap(pcSlice->getSliceCurStartCtuTsAddr()) );
    pcSlice->setSliceCurEndCtuTsAddr( tileMap.getCtuRsToTsAddrMap(pcSlice->getSliceCurEndCtuTsAddr()) );
#endif
#if HEVC_DEPENDENT_SLICES
  }
#endif


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

    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();

#if HEVC_DEPENDENT_SLICES
  }
#endif

#if HEVC_USE_SCALING_LISTS
  Quant *quant = m_cTrQuant.getQuant();

  if(pcSlice->getSPS()->getScalingListFlag())
  {
    ScalingList scalingList;
    if(pcSlice->getPPS()->getScalingListPresentFlag())
    {
      scalingList = pcSlice->getPPS()->getScalingList();
    }
    else if (pcSlice->getSPS()->getScalingListPresentFlag())
    {
      scalingList = pcSlice->getSPS()->getScalingList();
    }
    else
    {
      scalingList.setDefaultScalingList();
    }
    quant->setScalingListDec(scalingList);
    quant->setUseScalingList(true);
  }
  else
  {
    quant->setUseScalingList(false);
  }
#endif


  //  Decode a picture
  m_cSliceDecoder.decompressSlice( pcSlice, &(nalu.getBitstream()) );

  m_bFirstSliceInPicture = false;
  m_uiSliceSegmentIdx++;

  return false;
}

#if HEVC_VPS
void DecLib::xDecodeVPS( InputNALUnit& nalu )
{
  VPS* vps = new VPS();
  m_HLSReader.setBitstream( &nalu.getBitstream() );
  m_HLSReader.parseVPS( vps );
  m_parameterSetManager.storeVPS( vps, nalu.getBitstream().getFifo() );
}
#endif

void DecLib::xDecodeSPS( InputNALUnit& nalu )
{
  SPS* sps = new SPS();
  m_HLSReader.setBitstream( &nalu.getBitstream() );
  m_HLSReader.parseSPS( sps );
  m_parameterSetManager.storeSPS( sps, nalu.getBitstream().getFifo() );

  DTRACE( g_trace_ctx, D_QP_PER_CTU, "CTU Size: %dx%d", sps->getMaxCUWidth(), sps->getMaxCUHeight() );
}

void DecLib::xDecodePPS( InputNALUnit& nalu )
{
  PPS* pps = new PPS();
  m_HLSReader.setBitstream( &nalu.getBitstream() );
  m_HLSReader.parsePPS( pps );
  m_parameterSetManager.storePPS( pps, nalu.getBitstream().getFifo() );
}

bool DecLib::decode(InputNALUnit& nalu, int& iSkipFrame, int& iPOCLastDisplay)
{
  bool ret;
  // ignore all NAL units of layers > 0
  if (nalu.m_nuhLayerId > 0)
  {
    msg( WARNING, "Warning: found NAL unit with nuh_layer_id equal to %d. Ignoring.\n", nalu.m_nuhLayerId);
    return false;
  }

  switch (nalu.m_nalUnitType)
  {
#if HEVC_VPS
    case NAL_UNIT_VPS:
      xDecodeVPS( nalu );
      return false;
#endif

    case NAL_UNIT_SPS:
      xDecodeSPS( nalu );
      return false;

    case NAL_UNIT_PPS:
      xDecodePPS( nalu );
      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->SEIs, nalu.m_nalUnitType, m_parameterSetManager.getActiveSPS(), m_pDecodedSEIOutputStream );
      }
      else
      {
        msg( NOTICE, "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:
      ret = xDecodeSlice(nalu, iSkipFrame, iPOCLastDisplay);
#if JVET_J0090_MEMORY_BANDWITH_MEASURE
      if ( ret )
      {
        m_cacheModel.reportFrame( );
        m_cacheModel.accumulateFrame( );
        m_cacheModel.clear( );
      }
#endif
      return ret;

    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;
        uint32_t picType;
        audReader.parseAccessUnitDelimiter(&(nalu.getBitstream()),picType);
        msg( NOTICE, "Note: found NAL_UNIT_ACCESS_UNIT_DELIMITER\n");
        return false;
      }

    case NAL_UNIT_EOB:
      return false;

    case NAL_UNIT_FILLER_DATA:
      {
        FDReader fdReader;
        uint32_t size;
        fdReader.parseFillerData(&(nalu.getBitstream()),size);
        msg( NOTICE, "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:
#if !HEVC_VPS
    case NAL_UNIT_RESERVED_32:
#endif
      msg( NOTICE, "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:
      msg( NOTICE, "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:
      msg( NOTICE, "Note: found unspecified NAL unit.\n");
      return false;
    default:
      THROW( "Invalid NAL unit type" );
      break;
  }

  return false;
}

/** Function for checking if picture should be skipped because of association with a previous BLA picture
 *  This function skips all TFD pictures that follow a BLA picture in decoding order and precede it in output order.
 */
bool DecLib::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;
}

/** Function for checking if picture should be skipped because of random access. This function checks the skipping of pictures in the case of -s option random access.
 *  All pictures prior to the random access point indicated by the counter iSkipFrame are skipped.
 *  It also checks the type of Nal unit type at the random access point.
 *  If the random access point is CRA/CRANT/BLA/BLANT, TFD pictures with POC less than the POC of the random access point are skipped.
 *  If the random access point is IDR all pictures after the random access point are decoded.
 *  If the random access point is none of the above, a warning is issues, and decoding of pictures with POC
 *  equal to or greater than the random access point POC is attempted. For non IDR/CRA/BLA random
 *  access point there is no guarantee that the decoder will not crash.
 */
bool DecLib::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)
      {
        msg( WARNING, "\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;
}




//! \}