Merge branch 'JVET-O0162' into 'master'

JVET-O0162/O0331/O0480/O0574: IBC mvp flag conditioned on MaxNumMergeCand>1

See merge request !653

source/Lib/CommonLib/TypeDef.h

@@ -60,7 +60,7 @@
 
 #define JVET_O0164_REMOVE_AMVP_SPATIAL_SCALING            1 // JVET-O0164/JVET-O0587: remove spatial AMVP candidate scaling
 
-
+#define JVET_O0162_IBC_MVP_FLAG                           1 // JVET-O0162/O0331/O0480/O0574: IBC mvp flag conditioned on MaxNumMergeCand>1
 
 #define JVET_O0055_INT_DMVR_DIS_BDOF                                       1 // integer-distance DMVR cost to disable BDOF and disable BDOF early termination
 

source/Lib/DecoderLib/CABACReader.cpp

@@ -1509,6 +1509,13 @@ void CABACReader::prediction_unit( PredictionUnit& pu, MergeCtx& mrgCtx )
     pu.cu->affine = false;
     pu.refIdx[REF_PIC_LIST_0] = MAX_NUM_REF;
     mvd_coding(pu.mvd[REF_PIC_LIST_0]);
+#if JVET_O0162_IBC_MVP_FLAG
+    if ( pu.cu->slice->getMaxNumMergeCand() == 1 )
+    {
+      pu.mvpIdx[REF_PIC_LIST_0] = 0;
+    }
+    else
+#endif
     mvp_flag(pu, REF_PIC_LIST_0);
   }
   else

source/Lib/DecoderLib/DecCu.cpp

@@ -773,6 +773,12 @@ void DecCu::xDeriveCUMV( CodingUnit &cu )
           {
             mvd.changeIbcPrecAmvr2Internal(pu.cu->imv);
           }
+#if JVET_O0162_IBC_MVP_FLAG
+          if ( pu.cu->slice->getMaxNumMergeCand() == 1 )
+          {
+            CHECK( pu.mvpIdx[REF_PIC_LIST_0], "mvpIdx for IBC mode should be 0" );
+          }
+#endif
           pu.mv[REF_PIC_LIST_0] = amvpInfo.mvCand[pu.mvpIdx[REF_PIC_LIST_0]] + mvd;
           pu.mv[REF_PIC_LIST_0].mvCliptoStorageBitDepth();
         }

source/Lib/EncoderLib/CABACWriter.cpp

@@ -1415,6 +1415,13 @@ void CABACWriter::prediction_unit( const PredictionUnit& pu )
     Mv mvd = pu.mvd[REF_PIC_LIST_0];
     mvd.changeIbcPrecInternal2Amvr(pu.cu->imv);
     mvd_coding(mvd, 0); // already changed to signaling precision
+#if JVET_O0162_IBC_MVP_FLAG
+    if ( pu.cu->slice->getMaxNumMergeCand() == 1 )
+    {
+      CHECK( pu.mvpIdx[REF_PIC_LIST_0], "mvpIdx for IBC mode should be 0" );
+    }
+    else
+#endif
     mvp_flag(pu, REF_PIC_LIST_0);
   }
   else

source/Lib/EncoderLib/InterSearch.cpp

@@ -1431,6 +1431,14 @@ bool InterSearch::predIBCSearch(CodingUnit& cu, Partitioner& partitioner, const
     cMv.setZero();
     Distortion cost = 0;
 
+#if JVET_O0162_IBC_MVP_FLAG
+    if ( pu.cu->slice->getMaxNumMergeCand() == 1 )
+    {
+      iBvpNum = 1;
+      cMvPred[1] = cMvPred[0];
+    }
+#endif
+
     if (m_pcEncCfg->getIBCHashSearch())
     {
       xxIBCHashSearch(pu, cMvPred, iBvpNum, cMv, bvpIdxBest, ibcHashMap);