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/** \file     DecLibRecon.cpp

    \brief    decoder class

*/

#include "DecLib.h"

#include "CommonLib/TrQuant.h"

#if ENABLE_SIMD_TCOEFF_OPS

#include "CommonLib/TrQuant_EMT.h"

#endif

#include "CommonLib/InterPrediction.h"

#include "CommonLib/IntraPrediction.h"

#include "CommonLib/Unit.h"

#include "CommonLib/Buffer.h"

#include "CommonLib/UnitTools.h"

#include "CommonLib/dtrace_next.h"

#include "CommonLib/dtrace_buffer.h"

namespace vvdec

{

#ifdef TRACE_ENABLE_ITT

extern __itt_domain*              itt_domain_dec;

extern std::vector<__itt_domain*> itt_domain_decInst;

extern __itt_string_handle* itt_handle_alf;

extern __itt_string_handle* itt_handle_presao;

extern __itt_string_handle* itt_handle_sao;

extern __itt_string_handle* itt_handle_lfl;

extern __itt_string_handle* itt_handle_intra;

extern __itt_string_handle* itt_handle_inter;

extern __itt_string_handle* itt_handle_mider;

extern __itt_string_handle* itt_handle_lfcl;

extern __itt_string_handle* itt_handle_ext;

extern __itt_string_handle* itt_handle_dmvr;

extern __itt_string_handle* itt_handle_rsp;

extern __itt_string_handle* itt_handle_schedTasks;

extern __itt_string_handle* itt_handle_waitTasks;

// create global domain for DecLib

extern __itt_domain* itt_domain_glb;

// create a global counter

extern __itt_counter itt_frame_counter;

#define ITT_TASKSTART( d, t ) __itt_task_begin( ( d ), __itt_null, __itt_null, ( t ) )

#define ITT_TASKEND( d, t )   __itt_task_end  ( ( d ) )

#else

#define ITT_TASKSTART( d, t )

#define ITT_TASKEND( d, t )

#endif

//! \ingroup DecoderLib

//! \{

void CommonTaskParam::reset( CodingStructure& cs, TaskType ctuStartState, int tasksPerLine, bool _doALF )

{

  this->cs = &cs;

  const int heightInCtus = cs.pcv->heightInCtus;

  CHECKD( !ctuStates.empty() && std::any_of( ctuStates.begin(), ctuStates.end(), []( CtuState& s ) { return s != DONE; } ), "some CTUs of previous pic not done" );

  ctuStates = std::vector<CtuState>( heightInCtus * tasksPerLine );

  for( auto& ctu: ctuStates )

  {

    ctu.store( ctuStartState );

  }

  perLineMiHist = std::vector<MotionHist>( heightInCtus );

  doALF         = _doALF;

}

DecLibRecon::DecLibRecon()

{

#if ENABLE_SIMD_OPT_BUFFER

#  if defined( TARGET_SIMD_X86 )

  g_pelBufOP.initPelBufOpsX86();

#  endif

#  if defined( TARGET_SIMD_ARM )

  g_pelBufOP.initPelBufOpsARM();

#  endif

#endif

#if ENABLE_SIMD_TCOEFF_OPS && defined( TARGET_SIMD_X86 )

  g_tCoeffOps.initTCoeffOpsX86();

#endif

}

void DecLibRecon::create( ThreadPool* threadPool, unsigned instanceId, bool upscaleOutputEnabled )

{

  // run constructor again to ensure all variables, especially in DecLibParser have been reset

  this->~DecLibRecon();

  new( this ) DecLibRecon;

#if TRACE_ENABLE_ITT

  if( itt_domain_decInst.size() < instanceId + 1 )

  {

    std::string name( "DecLibRecon " + std::to_string( instanceId ) );

    itt_domain_decInst.push_back( __itt_domain_create( name.c_str() ) );

    itt_domain_decInst.back()->flags = 1;

    CHECK_FATAL( itt_domain_decInst.back() != itt_domain_decInst[instanceId], "current decLibRecon ITT-Domain is not the last in vector. Instances created in the wrong order?" );

  }

  m_itt_decInst = itt_domain_decInst[instanceId];

#endif

  m_decodeThreadPool = threadPool;

  m_numDecThreads    = std::max( 1, threadPool ? threadPool->numThreads() : 1 );

  m_upscaleOutputEnabled = upscaleOutputEnabled;

  m_predBufSize     = 0;

  m_dmvrMvCacheSize = 0;

  m_dmvrMvCache     = nullptr;

  m_num4x4Elements   = 0;

  m_loopFilterParam  = nullptr;

  m_motionInfo       = nullptr;

  m_pcThreadResource    = new PerThreadResource*[m_numDecThreads];

  m_pcThreadResource[0] = new PerThreadResource();

  for( int i = 1; i < m_numDecThreads; i++ )

  {

    m_pcThreadResource[i] = new PerThreadResource( m_pcThreadResource[0]->m_cTrQuant );

  }

}

void DecLibRecon::destroy()

{

  m_decodeThreadPool = nullptr;

  if( m_predBuf )

  {

    m_predBuf.reset();

    m_predBufSize = 0;

  }

  if( m_dmvrMvCache )

  {

    free( m_dmvrMvCache );

    m_dmvrMvCache = nullptr;

    m_dmvrMvCacheSize = 0;

  }

  if( m_loopFilterParam )

  {

    free( m_loopFilterParam );

    m_loopFilterParam = nullptr;

  }

  if( m_motionInfo )

  {

    free( m_motionInfo );

    m_motionInfo = nullptr;

  }

  m_num4x4Elements = 0;

  for( int i = 0; i < m_numDecThreads; i++ ) delete m_pcThreadResource[i];

  delete[] m_pcThreadResource; m_pcThreadResource = nullptr;

}

static void getCompatibleBuffer( const CodingStructure& cs, const CPelUnitBuf& srcBuf, PelStorage& destBuf, const UserAllocator* userAllocator )

{

  if( !destBuf.bufs.empty() )

  {

    bool compat = false;

    if( destBuf.chromaFormat == srcBuf.chromaFormat )

    {

      compat = true;

      const uint32_t numCh = getNumberValidComponents( srcBuf.chromaFormat );

      for( uint32_t i = 0; i < numCh; i++ )

      {

        // check this otherwise it would turn out to get very weird

        compat &= destBuf.get( ComponentID( i ) )         == srcBuf.get( ComponentID( i ) );

        compat &= destBuf.get( ComponentID( i ) ).stride  == srcBuf.get( ComponentID( i ) ).stride;

        compat &= destBuf.get( ComponentID( i ) ).width   == srcBuf.get( ComponentID( i ) ).width;

        compat &= destBuf.get( ComponentID( i ) ).height  == srcBuf.get( ComponentID( i ) ).height;

      }

    }

    if( !compat )

    {

      destBuf.destroy();

    }

  }

  if( destBuf.bufs.empty() )

  {

    destBuf.create( cs.picture->chromaFormat, cs.picture->lumaSize(), cs.pcv->maxCUWidth, cs.picture->margin, MEMORY_ALIGN_DEF_SIZE, true, userAllocator );

  }

}

void DecLibRecon::borderExtPic( Picture* pic, const Picture* currPic )

{

  // we block and wait here, so the exceptions from the reference pic don't propagate to the current picture

  pic->waitForAllTasks();

  if( pic->progress < Picture::reconstructed )   // an exception must have happended in the picture, so we need to clean it up

  {

    CHECK_FATAL( pic->progress < Picture::parsing, "Slice parsing should have started, so all structures are there" );

    try

    {

      pic->reconDone.checkAndRethrowException();

      pic->parseDone.checkAndRethrowException();  // when the error happened in the slice parsing tasks, there might not be an exception in recon done, so check parseDone also

    }

    catch( ... )

    {

      pic->error = true;

      pic->reconDone.clearException();

      // TODO: for now we set it on parseDone, so we can handle it outside:

      if( !pic->parseDone.hasException() )

      {

        pic->parseDone.setException( std::current_exception() );

      }

      pic->fillGrey( currPic->cs->sps.get() );

    }

  }

  pic->borderExtStarted = true;

  const bool wrapAround = pic->cs->sps->getUseWrapAround();

  if( wrapAround )

  {

    // copy reconstruction buffer to wrapAround buffer. All other border-extension tasks depend on this task.

    static auto copyTask = []( int, Picture* picture ) {

      ITT_TASKSTART( itt_domain_dec, itt_handle_ext );

      picture->getRecoBuf( true ).copyFrom( picture->getRecoBuf() );

      ITT_TASKEND( itt_domain_dec, itt_handle_ext );

      return true;

    };

    pic->m_copyWrapBufDone.lock();

    m_decodeThreadPool->addBarrierTask<Picture>( TP_TASK_NAME_ARG( "POC:" + std::to_string( currPic->poc ) + " copyTask Ref-POC:" + std::to_string( pic->poc ) )

                                                 copyTask,

                                                 pic,

                                                 &pic->m_borderExtTaskCounter,

                                                 &pic->m_copyWrapBufDone,

                                                 { &pic->reconDone } );

  }

  // start actual border extension tasks

  {

    static auto task = []( int, Picture* picture ) {

      ITT_TASKSTART( itt_domain_dec, itt_handle_ext );

      picture->extendPicBorder( true, false, false, false );

      ITT_TASKEND( itt_domain_dec, itt_handle_ext );

      return true;

    };

    m_decodeThreadPool->addBarrierTask<Picture>( TP_TASK_NAME_ARG( "POC:" + std::to_string(currPic->poc) + " borderExtTask T Ref-POC:" + std::to_string(pic->poc) )

                                                 task,

                                                 pic,

                                                 &pic->m_borderExtTaskCounter,

                                                 nullptr,

                                                 { wrapAround ? &pic->m_copyWrapBufDone : &pic->reconDone } );

  }

  {

    static auto task = []( int, Picture* picture ) {

      ITT_TASKSTART( itt_domain_dec, itt_handle_ext );

      picture->extendPicBorder( false, true, false, false );

      ITT_TASKEND( itt_domain_dec, itt_handle_ext );

      return true;

    };

    m_decodeThreadPool->addBarrierTask<Picture>( TP_TASK_NAME_ARG( "POC:" + std::to_string(currPic->poc) + " borderExtTask B Ref-POC:" + std::to_string(pic->poc) )

                                                 task,

                                                 pic,

                                                 &pic->m_borderExtTaskCounter,

                                                 nullptr,

                                                 { wrapAround ? &pic->m_copyWrapBufDone : &pic->reconDone } );

  }

  {

    static auto task = []( int, Picture* picture ) {

      ITT_TASKSTART( itt_domain_dec, itt_handle_ext );

      picture->extendPicBorder( false, false, true, false, CH_L );

      ITT_TASKEND( itt_domain_dec, itt_handle_ext );

      return true;

    };

    m_decodeThreadPool->addBarrierTask<Picture>( TP_TASK_NAME_ARG( "POC:" + std::to_string(currPic->poc) + " borderExtTask ltT Ref-POC:" + std::to_string(pic->poc) )

                                                 task,

                                                 pic,

                                                 &pic->m_borderExtTaskCounter,

                                                 nullptr,

                                                 { wrapAround ? &pic->m_copyWrapBufDone : &pic->reconDone } );

  }

  {

    static auto task = []( int, Picture* picture ) {

      ITT_TASKSTART( itt_domain_dec, itt_handle_ext );

      picture->extendPicBorder( false, false, false, true, CH_L );

      ITT_TASKEND( itt_domain_dec, itt_handle_ext );

      return true;

    };

    m_decodeThreadPool->addBarrierTask<Picture>( TP_TASK_NAME_ARG( "POC:" + std::to_string(currPic->poc) + " borderExtTask lrB Y Ref-POC:" + std::to_string(pic->poc) )

                                                 task,

                                                 pic,

                                                 &pic->m_borderExtTaskCounter,

                                                 nullptr,

                                                 { wrapAround ? &pic->m_copyWrapBufDone : &pic->reconDone } );

  }

  {

    static auto task = []( int, Picture* picture ) {

      ITT_TASKSTART( itt_domain_dec, itt_handle_ext );

      picture->extendPicBorder( false, false, true, false, CH_C );

      ITT_TASKEND( itt_domain_dec, itt_handle_ext );

      return true;

    };

    m_decodeThreadPool->addBarrierTask<Picture>( TP_TASK_NAME_ARG( "POC:" + std::to_string(currPic->poc) + " borderExtTask lrB UV Ref-POC:" + std::to_string(pic->poc) )

                                                 task,

                                                 pic,

                                                 &pic->m_borderExtTaskCounter,

                                                 nullptr,

                                                 { wrapAround ? &pic->m_copyWrapBufDone : &pic->reconDone } );

  }

  {

    static auto task = []( int, Picture* picture ) {

      ITT_TASKSTART( itt_domain_dec, itt_handle_ext );

      picture->extendPicBorder( false, false, false, true, CH_C );

      ITT_TASKEND( itt_domain_dec, itt_handle_ext );

      return true;

    };

    m_decodeThreadPool->addBarrierTask<Picture>( TP_TASK_NAME_ARG( "POC:" + std::to_string(currPic->poc) + " borderExtTask lrB UV Ref-POC:" + std::to_string(pic->poc) )

                                                 task,

                                                 pic,

                                                 &pic->m_borderExtTaskCounter,

                                                 nullptr,

                                                 { wrapAround ? &pic->m_copyWrapBufDone : &pic->reconDone } );

  }

}

void DecLibRecon::createSubPicRefBufs( Picture* pic, const Picture* currPic )

{

  pic->subPicExtStarted = true;

  const PPS* pps       = pic->cs->pps.get();

  const SPS* sps       = pic->cs->sps.get();

  const int  numSubPic = pps->getNumSubPics();

  pic->m_subPicRefBufs.resize( numSubPic );

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

  {

    const SubPic& currSubPic = pps->getSubPic( i );

    const Area    subPicArea( currSubPic.getSubPicLeft(),

                              currSubPic.getSubPicTop(),

                              currSubPic.getSubPicWidthInLumaSample(),

                              currSubPic.getSubPicHeightInLumaSample() );

    pic->m_subPicRefBufs[i].create( pic->chromaFormat, Size( subPicArea ), sps->getMaxCUWidth(), pic->margin, MEMORY_ALIGN_DEF_SIZE );

    static auto task = []( int, SubPicExtTask* t ) {

      t->subPicBuf->copyFrom( t->picture->getRecoBuf().subBuf( t->subPicArea ) );

      t->picture->extendPicBorderBuf( *t->subPicBuf );

      return true;

    };

    m_subPicExtTasks.emplace_back( SubPicExtTask{ pic, &pic->m_subPicRefBufs[i], subPicArea } );

    m_decodeThreadPool->addBarrierTask<SubPicExtTask>( TP_TASK_NAME_ARG( "POC:" + std::to_string( currPic->poc ) + " subPicBorderExtTask refPOC:" + std::to_string( pic->poc ) )

                                                       task,

                                                       &m_subPicExtTasks.back(),

                                                       &pic->m_borderExtTaskCounter,

                                                       nullptr,

                                                       { &pic->reconDone } );

  }

}

void DecLibRecon::swapBufs( CodingStructure& cs )

{

  cs.picture->m_bufs[PIC_RECONSTRUCTION].swap( m_fltBuf );

  cs.rebindPicBufs();   // ensure the recon buf in the coding structure points to the correct buffer

}

void DecLibRecon::decompressPicture( Picture* pcPic )

{

  m_currDecompPic = pcPic;

  CodingStructure& cs = *pcPic->cs;

  pcPic->progress = Picture::reconstructing;

#ifdef TRACE_ENABLE_ITT

  // mark start of frame

    pcPic->m_itt_decLibInst = m_itt_decInst;

  __itt_frame_begin_v3( pcPic->m_itt_decLibInst, nullptr );

#endif

  // Initialise the various objects for the new set of settings

  const SPS * sps = cs.sps.get();

  const PPS * pps = cs.pps.get();

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

  {

    if( sps->getUseReshaper() )

    {

      m_pcThreadResource[i]->m_cReshaper.createDec( sps->getBitDepth() );

      m_pcThreadResource[i]->m_cReshaper.initSlice( pcPic->slices[0]->getNalUnitLayerId(), *pcPic->slices[0]->getPicHeader(), pcPic->slices[0]->getVPS_nothrow() );

    }

    m_pcThreadResource[i]->m_cIntraPred.init( sps->getChromaFormatIdc(), sps->getBitDepth() );

    m_pcThreadResource[i]->m_cInterPred.init( &m_cRdCost, sps->getChromaFormatIdc(), sps->getMaxCUHeight() );

    // Recursive structure

    m_pcThreadResource[i]->m_cTrQuant.init( pcPic );

    m_pcThreadResource[i]->m_cCuDecoder.init( &m_pcThreadResource[i]->m_cIntraPred, &m_pcThreadResource[i]->m_cInterPred, &m_pcThreadResource[i]->m_cReshaper, &m_pcThreadResource[i]->m_cTrQuant );

  }

  getCompatibleBuffer( *pcPic->cs, pcPic->cs->getRecoBuf(), m_fltBuf, pcPic->getUserAllocator() );

  const uint32_t  log2SaoOffsetScale = (uint32_t) std::max(0, sps->getBitDepth() - MAX_SAO_TRUNCATED_BITDEPTH);

  const int maxDepth = getLog2(sps->getMaxCUWidth()) - pps->pcv->minCUWidthLog2;

  m_cSAO.create( pps->getPicWidthInLumaSamples(),

                 pps->getPicHeightInLumaSamples(),

                 sps->getChromaFormatIdc(),

                 sps->getMaxCUWidth(),

                 sps->getMaxCUHeight(),

                 maxDepth,

                 log2SaoOffsetScale,

                 m_fltBuf

               );

  if( sps->getUseALF() )

  {

    m_cALF.create( cs.picHeader.get(), sps, pps, m_numDecThreads, m_fltBuf );

  }

  const PreCalcValues* pcv = cs.pcv;

  // set reconstruction buffers in CodingStructure

  const ptrdiff_t ctuSampleSizeL = pcv->maxCUHeight * pcv->maxCUWidth;

  const ptrdiff_t ctuSampleSizeC = isChromaEnabled( pcv->chrFormat ) ? ( ctuSampleSizeL >> ( getChannelTypeScaleX( CH_C, pcv->chrFormat ) + getChannelTypeScaleY( CH_C, pcv->chrFormat ) ) ) : 0;

  const ptrdiff_t ctuSampleSize  = ctuSampleSizeL + 2 * ctuSampleSizeC;

  const size_t    predBufSize    = ctuSampleSize * pcv->sizeInCtus;

  if( predBufSize != m_predBufSize )

  {

    m_predBuf.reset( ( Pel* ) xMalloc( Pel, predBufSize ) );

    m_predBufSize = predBufSize;

  }

  pcPic->cs->m_predBuf = m_predBuf.get();

  // for the worst case of all PUs being 8x8 and using DMVR

  const size_t _maxNumDmvrMvs = pcv->num8x8CtuBlks * pcv->sizeInCtus;

  if( _maxNumDmvrMvs != m_dmvrMvCacheSize )

  {

    if( m_dmvrMvCache ) free( m_dmvrMvCache );

    m_dmvrMvCacheSize = _maxNumDmvrMvs;

    m_dmvrMvCache     = ( Mv* ) malloc( sizeof( Mv ) * _maxNumDmvrMvs );

  }

  pcPic->cs->m_dmvrMvCache = m_dmvrMvCache;

  if( m_num4x4Elements != cs.pcv->num4x4CtuBlks * cs.pcv->sizeInCtus )

  {

    if( m_loopFilterParam ) free( m_loopFilterParam );

    if( m_motionInfo      ) free( m_motionInfo );

    m_num4x4Elements = cs.pcv->num4x4CtuBlks * cs.pcv->sizeInCtus;

    m_loopFilterParam = ( LoopFilterParam* ) malloc( sizeof( LoopFilterParam ) * m_num4x4Elements * 2 );

    m_motionInfo      = ( MotionInfo* )      malloc( sizeof( MotionInfo      ) * m_num4x4Elements );

  }

  // finished

  const int widthInCtus  = cs.pcv->widthInCtus;

  const int heightInCtus = cs.pcv->heightInCtus;

  if( sps->getIBCFlag() )

  {

    cs.initVIbcBuf( heightInCtus, sps->getChromaFormatIdc(), sps->getMaxCUHeight() );

  }

  pcPic->startProcessingTimer();

  if( m_decodeThreadPool->numThreads() > 0 )

  {

    ITT_TASKSTART( itt_domain_dec, itt_handle_schedTasks );

  }

  picBarriers.clear();

#if ALLOW_MIDER_LF_DURING_PICEXT

  CBarrierVec  picExtBarriers;

#else

  CBarrierVec &picExtBarriers = picBarriers;

#endif

  const int numSubPic = cs.pps->getNumSubPics();

  if( numSubPic > 1 )

  {

    m_subPicExtTasks.clear();

    m_subPicExtTasks.reserve( pcPic->slices.size() * MAX_NUM_REF_PICS * numSubPic );

  }

  std::vector<Picture*> borderExtRefPics( pcPic->buildAllRefPicsVec() );

  for( Picture* refPic : borderExtRefPics )

  {

    if( !refPic->borderExtStarted )

    {

      // TODO: (GH) Can we bypass this border extension, when all subpics (>1) are treated as pics?

      borderExtPic( refPic, pcPic );

    }

    if( !refPic->subPicExtStarted && numSubPic > 1 && refPic->m_subPicRefBufs.size() != numSubPic )

    {

      CHECK( !refPic->m_subPicRefBufs.empty(), "Wrong number of subpics already present in reference picture" );

      CHECK( cs.sps->getUseWrapAround(), "Wraparound + subpics not implemented" );

      createSubPicRefBufs( refPic, pcPic );

    }

    if( refPic->m_borderExtTaskCounter.isBlocked() &&

        std::find( picExtBarriers.cbegin(), picExtBarriers.cend(), refPic->m_borderExtTaskCounter.donePtr() ) == picExtBarriers.cend() )

    {

      picExtBarriers.push_back( refPic->m_borderExtTaskCounter.donePtr() );

    }

  }

  if( m_decodeThreadPool->numThreads() == 0 && (

       std::any_of( picExtBarriers.cbegin(), picExtBarriers.cend(), []( const Barrier* b ) { return b->isBlocked(); } ) ||

       std::any_of( picBarriers   .cbegin(), picBarriers   .cend(), []( const Barrier* b ) { return b->isBlocked(); } ) ) )

  {

    m_decodeThreadPool->processTasksOnMainThread();

  }

  const bool isIntra = std::all_of( pcPic->slices.begin(), pcPic->slices.end(), []( const Slice* pcSlice ) { return pcSlice->isIntra(); } );

  const int numColPerTask = std::max( std::min( widthInCtus, ( widthInCtus / std::max( m_numDecThreads * ( isIntra ? 2 : 1 ), 1 ) ) + ( isIntra ? 0 : 1 ) ), 1 );

  const int numTasksPerLine = widthInCtus / numColPerTask + !!( widthInCtus % numColPerTask );

#if ALLOW_MIDER_LF_DURING_PICEXT

  pcPic->refPicExtDepBarriers = std::move( picExtBarriers );

#endif

#if !RECO_WHILE_PARSE

  picBarriers.push_back( &cs.picture->parseDone );

#endif

  const TaskType ctuStartState = MIDER;

  const bool     doALF         = cs.sps->getUseALF() && !AdaptiveLoopFilter::getAlfSkipPic( cs );

  commonTaskParam.reset( cs, ctuStartState, numTasksPerLine, doALF );

  tasksFinishMotion = std::vector<LineTaskParam>( heightInCtus, LineTaskParam{ commonTaskParam, -1 } );

  tasksCtu          = std::vector<CtuTaskParam >( heightInCtus * numTasksPerLine, CtuTaskParam{ commonTaskParam, -1, -1, {} } );

  pcPic->reconDone.lock();

#if 0

  // schedule in raster scan order

  for( int line = 0; line < heightInCtus; ++line )

  {

    for( int col = 0; col < widthInCtus;  ++col )

    {

#else

  // schedule in zig-zag scan order

  for( int i = 0; i < numTasksPerLine + heightInCtus; ++i )

  {

    int line = 0;

    for( int col = i; col >= 0; --col, ++line )

    {

#endif

      if( line < heightInCtus && col < numTasksPerLine )

      {

        CBarrierVec ctuBarriesrs = picBarriers;

        const int   ctuStart     = col * numColPerTask;

        const int   ctuEnd       = std::min( ctuStart + numColPerTask, widthInCtus );

#if RECO_WHILE_PARSE

        // wait for the last CTU in the current line to be parsed

        ctuBarriesrs.push_back( &pcPic->ctuParsedBarrier[( line + 1 ) * widthInCtus - 1] );

#endif

        CtuTaskParam* param    = &tasksCtu[line * numTasksPerLine + col];

        param->taskLine        = line;

        param->taskCol         = col;

        param->ctuEnd          = ctuEnd;

        param->ctuStart        = ctuStart;

        param->numColPerTask   = numColPerTask;

        param->numTasksPerLine = numTasksPerLine;

        m_decodeThreadPool->addBarrierTask<CtuTaskParam>( TP_TASK_NAME_ARG( "POC:" + std::to_string(pcPic->poc) + " ctuTask:" + std::to_string( col ) + "," + std::to_string( line ) )

                                                          ctuTask<false>,

                                                          param,

                                                          &pcPic->m_ctuTaskCounter,

                                                          nullptr,

                                                          std::move( ctuBarriesrs ),

                                                          ctuTask<true> );

      }

    }

  }

  {

    static auto finishReconTask = []( int, FinishPicTaskParam* param )

    {

      CodingStructure& cs = *param->pic->cs;

      if( cs.sps->getUseALF() && !AdaptiveLoopFilter::getAlfSkipPic( cs ) )

      {

        param->decLib->swapBufs( cs );

      }

      cs.deallocTempInternals();

#ifdef TRACE_ENABLE_ITT

      // mark end of frame

      __itt_frame_end_v3( param->pic->m_itt_decLibInst, nullptr );

#endif

      param->pic->stopProcessingTimer();

      param->pic->progress = Picture::reconstructed;

      return true;

    };

    taskFinishPic = FinishPicTaskParam( this, pcPic );

    m_decodeThreadPool->addBarrierTask<FinishPicTaskParam>( TP_TASK_NAME_ARG( "POC:" + std::to_string( pcPic->poc ) + " finishPicTask" )

                                                            finishReconTask,

                                                            &taskFinishPic,

                                                            &pcPic->m_divTasksCounter,

                                                            &pcPic->reconDone,

                                                            { pcPic->m_ctuTaskCounter.donePtr() } );

  }

  if( m_decodeThreadPool->numThreads() == 0 )

  {

  }

  else

  {

    ITT_TASKEND( itt_domain_dec, itt_handle_schedTasks );

  }

}

Picture* DecLibRecon::waitForPrevDecompressedPic()

{

  if( !m_currDecompPic )

    return nullptr;

  ITT_TASKSTART( itt_domain_dec, itt_handle_waitTasks );

  if( m_decodeThreadPool->numThreads() == 0 )

  {

    m_decodeThreadPool->processTasksOnMainThread();

    CHECK_FATAL( m_currDecompPic->reconDone.isBlocked(), "can't make progress. some dependecy has not been finished" );

  }

  try

  {

    m_currDecompPic->reconDone.wait();

  }

  catch( ... )

  {

    m_currDecompPic->error = true;

  }

  // also check error flag, which can have been set earlier (e.g., when trying to use the picture as reference)

  if( m_currDecompPic->error || m_currDecompPic->reconDone.hasException() )

  {

    // ensure all tasks are cleared from declibRecon

    cleanupOnException( std::current_exception() );

  }

  ITT_TASKEND( itt_domain_dec, itt_handle_waitTasks );

  return std::exchange( m_currDecompPic, nullptr );

}

void DecLibRecon::cleanupOnException( std::exception_ptr exception )

{

  // there was an exception anywhere in m_currDecompPic

  // => we need to wait for all tasks to be cleared from the thread pool

  m_currDecompPic->waitForAllTasks();

  commonTaskParam.ctuStates.clear();

}

template<bool onlyCheckReadyState>

bool DecLibRecon::ctuTask( int tid, CtuTaskParam* param )

{

  const int       taskCol      = param->taskCol;

  const int       line         = param->taskLine;

  const int       col          = taskCol;

  auto&           cs           = *param->common.cs;

  auto&           decLib       = param->common.decLib;

  const int       tasksPerLine = param->numTasksPerLine;

  const int       heightInCtus = cs.pcv->heightInCtus;

  CtuState&       thisCtuState =  param->common.ctuStates[line * tasksPerLine + taskCol];

  const CtuState* thisLine     = &param->common.ctuStates[line * tasksPerLine];

  const CtuState* lineAbove    = thisLine - tasksPerLine;

  const CtuState* lineBelow    = thisLine + tasksPerLine;

  const int       ctuStart     = param->ctuStart;

  const int       ctuEnd       = param->ctuEnd;

  try

  {

    if( cs.picture->m_ctuTaskCounter.hasException() )

    {

      std::rethrow_exception( cs.picture->m_ctuTaskCounter.getException() );

    }

    switch( thisCtuState.load() )

    {

      // all case statements fall through to continue with next task, unless they return false due to unsatisfied preconditions

    case MIDER:

    {

      if( col > 0 && thisLine[col - 1] <= MIDER_cont )

        return false;

      if( line > 0 )

      {

        if( col + 1 < tasksPerLine )

        {

          if( lineAbove[col + 1] <= MIDER )

            return false;

        }

        else

        {

          if( lineAbove[col] <= MIDER_cont )

            return false;

        }

      }

      if( onlyCheckReadyState )

        return true;

      ITT_TASKSTART( itt_domain_dec, itt_handle_mider );

      for( int ctu = ctuStart; ctu < ctuEnd; ctu++ )

      {

        const int ctuRsAddr = ctu + line * cs.pcv->widthInCtus;

        CtuData& ctuData    = cs.getCtuData( ctuRsAddr );

        ctuData.motion      = &decLib.m_motionInfo[cs.pcv->num4x4CtuBlks * ctuRsAddr];

        if( !ctuData.slice->isIntra() || cs.sps->getIBCFlag() )

        {

          const UnitArea ctuArea = getCtuArea( cs, ctu, line, true );

          decLib.m_pcThreadResource[tid]->m_cCuDecoder.TaskDeriveCtuMotionInfo( cs, ctuRsAddr, ctuArea, param->common.perLineMiHist[line] );

        }

        else

        {

          memset( NO_WARNING_class_memaccess( ctuData.motion ), MI_NOT_VALID, sizeof( MotionInfo ) * cs.pcv->num4x4CtuBlks );

        }

        thisCtuState = MIDER_cont;

      }

      thisCtuState = LF_INIT;

      ITT_TASKEND( itt_domain_dec, itt_handle_mider );

    }

    case LF_INIT:

    {

      if( onlyCheckReadyState )

        return true;

      ITT_TASKSTART( itt_domain_dec, itt_handle_lfcl );

      for( int ctu = ctuStart; ctu < ctuEnd; ctu++ )

      {

        const int ctuRsAddr = ctu + line * cs.pcv->widthInCtus;

        CtuData& ctuData    = cs.getCtuData( ctuRsAddr );

        ctuData.lfParam[0]  = &decLib.m_loopFilterParam[cs.pcv->num4x4CtuBlks * ( 2 * ctuRsAddr + 0 )];

        ctuData.lfParam[1]  = &decLib.m_loopFilterParam[cs.pcv->num4x4CtuBlks * ( 2 * ctuRsAddr + 1 )];

        memset( ctuData.lfParam[0], 0, sizeof( LoopFilterParam ) * 2 * cs.pcv->num4x4CtuBlks );

        decLib.m_cLoopFilter.calcFilterStrengthsCTU( cs, ctuRsAddr );

      }

      thisCtuState = INTER;

      ITT_TASKEND( itt_domain_dec, itt_handle_lfcl );

    }

    case INTER:

    {

      if( std::all_of( cs.picture->slices.begin(), cs.picture->slices.end(), []( const Slice* pcSlice ) { return pcSlice->isIntra(); } ) )

Unexecuted instantiation: vvdec::DecLibRecon::ctuTask<false>(int, vvdec::CtuTaskParam*)::{lambda(vvdec::Slice const*)#1}::operator()(vvdec::Slice const*) const

Unexecuted instantiation: vvdec::DecLibRecon::ctuTask<true>(int, vvdec::CtuTaskParam*)::{lambda(vvdec::Slice const*)#1}::operator()(vvdec::Slice const*) const

      {

        // not really necessary, but only for optimizing the wave-fronts

        if( col > 1 && thisLine[col - 2] <= INTER )

          return false;

        if( line > 0 && lineAbove[col] <= INTER )

          return false;

      }

      if( std::any_of( cs.picture->refPicExtDepBarriers.cbegin(), cs.picture->refPicExtDepBarriers.cend(), []( const Barrier* b ) { return b->isBlocked(); } ) )

Unexecuted instantiation: vvdec::DecLibRecon::ctuTask<false>(int, vvdec::CtuTaskParam*)::{lambda(vvdec::Barrier const*)#1}::operator()(vvdec::Barrier const*) const

Unexecuted instantiation: vvdec::DecLibRecon::ctuTask<true>(int, vvdec::CtuTaskParam*)::{lambda(vvdec::Barrier const*)#1}::operator()(vvdec::Barrier const*) const

      {

        return false;

      }

      if( onlyCheckReadyState )

        return true;

      ITT_TASKSTART( itt_domain_dec, itt_handle_inter );

      for( int ctu = ctuStart; ctu < ctuEnd; ctu++ )

      {

        const int ctuRsAddr    = ctu + line * cs.pcv->widthInCtus;

        const UnitArea ctuArea = getCtuArea( cs, ctu, line, true );

        const CtuData& ctuData = cs.getCtuData( ctuRsAddr );

        decLib.m_pcThreadResource[tid]->m_cCuDecoder.TaskTrafoCtu( cs, ctuRsAddr, ctuArea );

        if( !ctuData.slice->isIntra() )

        {

          decLib.m_pcThreadResource[tid]->m_cCuDecoder.TaskInterCtu( cs, ctuRsAddr, ctuArea );

          if( cs.picture->stillReferenced )

          {

            decLib.m_pcThreadResource[tid]->m_cCuDecoder.TaskFinishMotionInfo( cs, ctuRsAddr, ctu, line );

          }

        }

      }

      thisCtuState = INTRA;

      ITT_TASKEND( itt_domain_dec, itt_handle_inter );

    }

    case INTRA:

    {

      if( col > 0 && thisLine[col - 1] <= INTRA_cont )

        return false;

      if( line > 0 )

      {

        if( col + 1 < tasksPerLine )

        {

          if( lineAbove[col + 1] <= INTRA )

            return false;

        }

        else

        {

          if( lineAbove[col] <= INTRA_cont )

            return false;

        }

      }

      if( onlyCheckReadyState )

        return true;

      ITT_TASKSTART( itt_domain_dec, itt_handle_intra );

      for( int ctu = ctuStart; ctu < ctuEnd; ctu++ )

      {

        const int ctuRsAddr    = ctu + line * cs.pcv->widthInCtus;

        const UnitArea ctuArea = getCtuArea( cs, ctu, line, true );

        decLib.m_pcThreadResource[tid]->m_cCuDecoder.TaskCriticalIntraKernel( cs, ctuRsAddr, ctuArea );

        thisCtuState = INTRA_cont;

      }

      thisCtuState = RSP;

      ITT_TASKEND( itt_domain_dec, itt_handle_intra );

    }

    case RSP:

    {

      // RIRZIIIII

      // IIIIIXXXX