diff --git a/cfg/encoder_intra_vtm.cfg b/cfg/encoder_intra_vtm.cfg
index 685d9d1ff5d0a8f5d25203532d6f70cca990cb31..bcbc825667b99c97fa8567d5b24595425af38bcc 100644
--- a/cfg/encoder_intra_vtm.cfg
+++ b/cfg/encoder_intra_vtm.cfg
@@ -88,6 +88,7 @@ LMChroma : 1 # use CCLM only
DepQuant : 1
IMV : 1
ALF : 1
+ALFStrength : 1.0
IBC : 0 # turned off in CTC
AllowDisFracMMVD : 1
AffineAmvr : 0
diff --git a/cfg/encoder_lowdelay_P_vtm.cfg b/cfg/encoder_lowdelay_P_vtm.cfg
index 1a78ff8bd9665e68813e1367a7c94a062917f9fa..228b11448597b7f545d326f07e6fe2b9c77fa505 100644
--- a/cfg/encoder_lowdelay_P_vtm.cfg
+++ b/cfg/encoder_lowdelay_P_vtm.cfg
@@ -111,6 +111,7 @@ LMChroma : 1 # use CCLM only
DepQuant : 1
IMV : 1
ALF : 1
+ALFStrength : 1.0
CIIP : 1
IBC : 0 # turned off in CTC
AllowDisFracMMVD : 1
diff --git a/cfg/encoder_lowdelay_vtm.cfg b/cfg/encoder_lowdelay_vtm.cfg
index e8b3e708a0fceb7bd262d2c4b840bc7774fc8d14..7128d34d7704f00ce0ec7c63a9ac763153b5ff19 100644
--- a/cfg/encoder_lowdelay_vtm.cfg
+++ b/cfg/encoder_lowdelay_vtm.cfg
@@ -112,6 +112,7 @@ LMChroma : 1 # use CCLM only
DepQuant : 1
IMV : 1
ALF : 1
+ALFStrength : 1.0
BCW : 1
BcwFast : 1
CIIP : 1
diff --git a/cfg/encoder_randomaccess_vtm.cfg b/cfg/encoder_randomaccess_vtm.cfg
index 0b7a5a0b74b8216763c0cc301adb084f636d6961..7335eb88b4b476c072c585f1de531e933a850e34 100644
--- a/cfg/encoder_randomaccess_vtm.cfg
+++ b/cfg/encoder_randomaccess_vtm.cfg
@@ -140,6 +140,7 @@ LMChroma : 1 # use CCLM only
DepQuant : 1
IMV : 1
ALF : 1
+ALFStrength : 1.0
BCW : 1
BcwFast : 1
BIO : 1
diff --git a/cfg/encoder_randomaccess_vtm_gop16.cfg b/cfg/encoder_randomaccess_vtm_gop16.cfg
index ae60960facf3fe4c196607dd9b05481c0ef43d33..ad36d6b97d06e2e5c29e47fded7445b3a0051275 100644
--- a/cfg/encoder_randomaccess_vtm_gop16.cfg
+++ b/cfg/encoder_randomaccess_vtm_gop16.cfg
@@ -124,6 +124,7 @@ LMChroma : 1 # use CCLM only
DepQuant : 1
IMV : 1
ALF : 1
+ALFStrength : 1.0
BCW : 1
BcwFast : 1
BIO : 1
diff --git a/doc/software-manual.tex b/doc/software-manual.tex
index 21d80063e3c767809c5d561cfc87fd00dad42271..e0b757176f14b2e2ee8baf70c27307ebf68d23db 100644
--- a/doc/software-manual.tex
+++ b/doc/software-manual.tex
@@ -2868,6 +2868,12 @@ switched at CTB level. Set to 1 to disable alternative chroma filters.
Value shall be in the range 1..8.
\\
+\Option{ALFStrength} &
+%\ShortOption{\None} &
+\Default{1.0} &
+Enables control of ALF filter strength. The parameter scales the magnitudes of the ALF filter coefficients for both luma and chroma.
+\\
+
\Option{CCALF} &
%\ShortOption{\None} &
\Default{true} &
diff --git a/source/App/EncoderApp/EncApp.cpp b/source/App/EncoderApp/EncApp.cpp
index 86afb73ab8be1dedd06e1e666250a7251870d105..9fde5120b06f16e7dfcd1294260193c8c1fb967f 100644
--- a/source/App/EncoderApp/EncApp.cpp
+++ b/source/App/EncoderApp/EncApp.cpp
@@ -1036,6 +1036,9 @@ void EncApp::xInitLibCfg()
m_cEncLib.setForceSingleSplitThread ( m_forceSplitSequential );
#endif
m_cEncLib.setUseALF ( m_alf );
+#if JVET_T0064
+ m_cEncLib.setALFStrength (m_alfStrength);
+#endif
m_cEncLib.setUseCCALF ( m_ccalf );
m_cEncLib.setCCALFQpThreshold ( m_ccalfQpThreshold );
m_cEncLib.setLmcs ( m_lmcsEnabled );
diff --git a/source/App/EncoderApp/EncAppCfg.cpp b/source/App/EncoderApp/EncAppCfg.cpp
index faea0ed16167c400a79673b7c9a56ddfb8089c9d..e4806a2ce58d9384e6d3d5f4d82f78930064c3b8 100644
--- a/source/App/EncoderApp/EncAppCfg.cpp
+++ b/source/App/EncoderApp/EncAppCfg.cpp
@@ -1375,6 +1375,9 @@ bool EncAppCfg::parseCfg( int argc, char* argv[] )
("DebugCTU", m_debugCTU, -1, "If DebugBitstream is present, load frames up to this POC from this bitstream. Starting with DebugPOC-frame at CTUline containin debug CTU.")
("EnsureWppBitEqual", m_ensureWppBitEqual, false, "Ensure the results are equal to results with WPP-style parallelism, even if WPP is off")
( "ALF", m_alf, true, "Adaptive Loop Filter\n" )
+#if JVET_T0064
+ ("ALFStrength", m_alfStrength, 1.0, "Adaptive Loop Filter strength. The parameter scales the magnitudes of the ALF filter coefficients for both luma and chroma.")
+#endif
( "CCALF", m_ccalf, true, "Cross-component Adaptive Loop Filter" )
( "CCALFQpTh", m_ccalfQpThreshold, 37, "QP threshold above which encoder reduces CCALF usage")
( "RPR", m_rprEnabledFlag, true, "Reference Sample Resolution" )
diff --git a/source/App/EncoderApp/EncAppCfg.h b/source/App/EncoderApp/EncAppCfg.h
index 7f8d114143fcd8d48b52a476efc032c74f59c3fd..25ccd97101dd2158c5ffc845ea720b6d63b06b77 100644
--- a/source/App/EncoderApp/EncAppCfg.h
+++ b/source/App/EncoderApp/EncAppCfg.h
@@ -693,6 +693,9 @@ protected:
bool m_forceDecodeBitstream1;
bool m_alf; ///< Adaptive Loop Filter
+#if JVET_T0064
+ double m_alfStrength;
+#endif
bool m_ccalf;
int m_ccalfQpThreshold;
diff --git a/source/Lib/CommonLib/TypeDef.h b/source/Lib/CommonLib/TypeDef.h
index 933b9db6e30c6385f57f093f4d3e07fb520fb6cb..be47c68b83df324ea05bdf540c9391b412704146 100644
--- a/source/Lib/CommonLib/TypeDef.h
+++ b/source/Lib/CommonLib/TypeDef.h
@@ -55,6 +55,7 @@
#define JVET_S0219_ASPECT1 1 // JVET-S0219 aspect1 : removal non-referred APS parameter set in the non-output layer.
#define JVET_R0193 1 // JVET-R0193: signalling of the number of maximum sublayers used for inter-layer prediction for each layer
#define JVET_R0193_S0141 1 // JVET-S0141 item 47 : item 47: In the general sub-bitstream extraction process, specify the conditions under which an output sub-bitstream is required to be a conforming bitstream such that the value of tIdTarget is specified to be in the range of 0 to vps_ptl_max_tid[ vps_ols_ptl_idx[ targetOlsIdx ] ], inclusive (instead of 0 to 6 inclusive). (JVET-S0158 aspect 1)
+#define JVET_T0064 1 // JVET-T0064: control of filter strength for ALF
//########### place macros to be be kept below this line ###############
#define JVET_S0257_DUMP_360SEI_MESSAGE 1 // Software support of 360 SEI messages
diff --git a/source/Lib/EncoderLib/EncAdaptiveLoopFilter.cpp b/source/Lib/EncoderLib/EncAdaptiveLoopFilter.cpp
index f034b57d93aed18c21efd4f6a6713e9c70660a35..5aa96f3d0d14d543ab7ddd39bac1ea10900b1f19 100644
--- a/source/Lib/EncoderLib/EncAdaptiveLoopFilter.cpp
+++ b/source/Lib/EncoderLib/EncAdaptiveLoopFilter.cpp
@@ -1834,7 +1834,12 @@ double EncAdaptiveLoopFilter::deriveCoeffQuant( int *filterClipp, int *filterCoe
filterCoeffQuant[numCoeff - 1] = 0;
int modified=1;
-
+#if JVET_T0064
+ if( m_encCfg->getALFStrength() != 1.0 )
+ {
+ modified = 0;
+ }
+#endif
double errRef=cov.calcErrorForCoeffs( filterClipp, filterCoeffQuant, numCoeff, bitDepth );
while( modified )
{
@@ -1878,7 +1883,11 @@ void EncAdaptiveLoopFilter::roundFiltCoeff( int *filterCoeffQuant, double *filte
for( int i = 0; i < numCoeff; i++ )
{
int sign = filterCoeff[i] > 0 ? 1 : -1;
+#if JVET_T0064
+ filterCoeffQuant[i] = int((filterCoeff[i] * m_encCfg->getALFStrength()) * sign * factor + 0.5) * sign;
+#else
filterCoeffQuant[i] = int( filterCoeff[i] * sign * factor + 0.5 ) * sign;
+#endif
}
}
@@ -2721,7 +2730,16 @@ void EncAdaptiveLoopFilter::alfEncoderCtb(CodingStructure& cs, AlfParam& alfPar
double costOn = MAX_DOUBLE;
ctxTempStart = AlfCtx(m_CABACEstimator->getCtx());
int iBestFilterSetIdx = 0;
+#if JVET_T0064
+ int firstFilterSetIdx = 0;
+ if (m_encCfg->getALFStrength() != 1.0)
+ {
+ firstFilterSetIdx = NUM_FIXED_FILTER_SETS;
+ }
+ for (int filterSetIdx = firstFilterSetIdx; filterSetIdx < numFilterSet; filterSetIdx++)
+#else
for (int filterSetIdx = 0; filterSetIdx < numFilterSet; filterSetIdx++)
+#endif
{
//rate
m_CABACEstimator->getCtx() = AlfCtx(ctxTempStart);
diff --git a/source/Lib/EncoderLib/EncCfg.h b/source/Lib/EncoderLib/EncCfg.h
index 1f15e503e1b5343ca95726ac46d23228304a6df2..ddd1aa4d6f325f5e1ce53cbcf5f74f43c850ecd5 100644
--- a/source/Lib/EncoderLib/EncCfg.h
+++ b/source/Lib/EncoderLib/EncCfg.h
@@ -732,6 +732,9 @@ protected:
#endif
bool m_alf; ///< Adaptive Loop Filter
+#if JVET_T0064
+ double m_alfStrength;
+#endif
bool m_ccalf;
int m_ccalfQpThreshold;
#if JVET_O0756_CALCULATE_HDRMETRICS
@@ -1903,6 +1906,10 @@ public:
#endif
void setUseALF( bool b ) { m_alf = b; }
bool getUseALF() const { return m_alf; }
+#if JVET_T0064
+ void setALFStrength( double s) { m_alfStrength = s; }
+ double getALFStrength() const { return m_alfStrength; }
+#endif
void setUseCCALF( bool b ) { m_ccalf = b; }
bool getUseCCALF() const { return m_ccalf; }
void setCCALFQpThreshold( int b ) { m_ccalfQpThreshold = b; }