diff --git a/modules/core/src/matmul.dispatch.cpp b/modules/core/src/matmul.dispatch.cpp
index 35b7ad54c4..c78fcc0b7a 100644
--- a/modules/core/src/matmul.dispatch.cpp
+++ b/modules/core/src/matmul.dispatch.cpp
@@ -696,7 +696,7 @@ void calcCovarMatrix( const Mat* data, int nsamples, Mat& covar, Mat& _mean, int
     Mat mean;
     ctype = std::max(std::max(CV_MAT_DEPTH(ctype >= 0 ? ctype : type), _mean.depth()), CV_32F);
 
-    if( (flags & CV_COVAR_USE_AVG) != 0 )
+    if( (flags & cv::COVAR_USE_AVG) != 0 )
     {
         CV_Assert( _mean.size() == size );
         if( _mean.isContinuous() && _mean.type() == ctype )
@@ -722,8 +722,8 @@ void calcCovarMatrix( const Mat* data, int nsamples, Mat& covar, Mat& _mean, int
         }
     }
 
-    calcCovarMatrix( _data, covar, mean, (flags & ~(CV_COVAR_ROWS|CV_COVAR_COLS)) | CV_COVAR_ROWS, ctype );
-    if( (flags & CV_COVAR_USE_AVG) == 0 )
+    calcCovarMatrix( _data, covar, mean, (flags & ~(cv::COVAR_ROWS|cv::COVAR_COLS)) | cv::COVAR_ROWS, ctype );
+    if( (flags & cv::COVAR_USE_AVG) == 0 )
         _mean = mean.reshape(1, size.height);
 }
 
@@ -754,7 +754,7 @@ void calcCovarMatrix( InputArray _src, OutputArray _covar, InputOutputArray _mea
         }
 
         Mat mean;
-        if( (flags & CV_COVAR_USE_AVG) != 0 )
+        if( (flags & cv::COVAR_USE_AVG) != 0 )
         {
             CV_Assert( _mean.size() == size );
 
@@ -770,9 +770,9 @@ void calcCovarMatrix( InputArray _src, OutputArray _covar, InputOutputArray _mea
             mean = _mean.getMat().reshape(1, 1);
         }
 
-        calcCovarMatrix( _data, _covar, mean, (flags & ~(CV_COVAR_ROWS|CV_COVAR_COLS)) | CV_COVAR_ROWS, ctype );
+        calcCovarMatrix( _data, _covar, mean, (flags & ~(cv::COVAR_ROWS|cv::COVAR_COLS)) | cv::COVAR_ROWS, ctype );
 
-        if( (flags & CV_COVAR_USE_AVG) == 0 )
+        if( (flags & cv::COVAR_USE_AVG) == 0 )
         {
             mean = mean.reshape(1, size.height);
             mean.copyTo(_mean);
@@ -781,14 +781,14 @@ void calcCovarMatrix( InputArray _src, OutputArray _covar, InputOutputArray _mea
     }
 
     Mat data = _src.getMat(), mean;
-    CV_Assert( ((flags & CV_COVAR_ROWS) != 0) ^ ((flags & CV_COVAR_COLS) != 0) );
-    bool takeRows = (flags & CV_COVAR_ROWS) != 0;
+    CV_Assert( ((flags & cv::COVAR_ROWS) != 0) ^ ((flags & cv::COVAR_COLS) != 0) );
+    bool takeRows = (flags & cv::COVAR_ROWS) != 0;
     int type = data.type();
     int nsamples = takeRows ? data.rows : data.cols;
     CV_Assert( nsamples > 0 );
     Size size = takeRows ? Size(data.cols, 1) : Size(1, data.rows);
 
-    if( (flags & CV_COVAR_USE_AVG) != 0 )
+    if( (flags & cv::COVAR_USE_AVG) != 0 )
     {
         mean = _mean.getMat();
         ctype = std::max(std::max(CV_MAT_DEPTH(ctype >= 0 ? ctype : type), mean.depth()), CV_32F);
@@ -808,8 +808,8 @@ void calcCovarMatrix( InputArray _src, OutputArray _covar, InputOutputArray _mea
         mean = _mean.getMat();
     }
 
-    mulTransposed( data, _covar, ((flags & CV_COVAR_NORMAL) == 0) ^ takeRows,
-        mean, (flags & CV_COVAR_SCALE) != 0 ? 1./nsamples : 1, ctype );
+    mulTransposed( data, _covar, ((flags & cv::COVAR_NORMAL) == 0) ^ takeRows,
+        mean, (flags & cv::COVAR_SCALE) != 0 ? 1./nsamples : 1, ctype );
 }
 
 
@@ -1171,7 +1171,7 @@ cvCalcCovarMatrix( const CvArr** vecarr, int count,
     if( avgarr )
         mean = mean0 = cv::cvarrToMat(avgarr);
 
-    if( (flags & CV_COVAR_COLS) != 0 || (flags & CV_COVAR_ROWS) != 0 )
+    if( (flags & cv::COVAR_COLS) != 0 || (flags & cv::COVAR_ROWS) != 0 )
     {
 
         cv::Mat data = cv::cvarrToMat(vecarr[0]);
diff --git a/modules/core/src/matrix_expressions.cpp b/modules/core/src/matrix_expressions.cpp
index dd39d50a01..86acab9d93 100644
--- a/modules/core/src/matrix_expressions.cpp
+++ b/modules/core/src/matrix_expressions.cpp
@@ -554,7 +554,7 @@ void MatOp::matmul(const MatExpr& e1, const MatExpr& e2, MatExpr& res) const
 
         if( isT(e1) )
         {
-            flags = CV_GEMM_A_T;
+            flags = cv::GEMM_1_T;
             scale = e1.alpha;
             m1 = e1.a;
         }
@@ -568,7 +568,7 @@ void MatOp::matmul(const MatExpr& e1, const MatExpr& e2, MatExpr& res) const
 
         if( isT(e2) )
         {
-            flags |= CV_GEMM_B_T;
+            flags |= cv::GEMM_2_T;
             scale *= e2.alpha;
             m2 = e2.a;
         }
@@ -1574,10 +1574,10 @@ void MatOp_GEMM::add(const MatExpr& e1, const MatExpr& e2, MatExpr& res) const
     double alpha1 = i1 ? 1 : e1.alpha, alpha2 = i2 ? 1 : e2.alpha;
 
     if( isMatProd(e1) && (i2 || isScaled(e2) || isT(e2)) )
-        MatOp_GEMM::makeExpr(res, (e1.flags & ~CV_GEMM_C_T)|(isT(e2) ? CV_GEMM_C_T : 0),
+        MatOp_GEMM::makeExpr(res, (e1.flags & ~cv::GEMM_3_T)|(isT(e2) ? cv::GEMM_3_T : 0),
                              e1.a, e1.b, alpha1, e2.a, alpha2);
     else if( isMatProd(e2) && (i1 || isScaled(e1) || isT(e1)) )
-        MatOp_GEMM::makeExpr(res, (e2.flags & ~CV_GEMM_C_T)|(isT(e1) ? CV_GEMM_C_T : 0),
+        MatOp_GEMM::makeExpr(res, (e2.flags & ~cv::GEMM_3_T)|(isT(e1) ? cv::GEMM_3_T : 0),
                              e2.a, e2.b, alpha2, e1.a, alpha1);
     else if( this == e2.op )
         MatOp::add(e1, e2, res);
@@ -1593,10 +1593,10 @@ void MatOp_GEMM::subtract(const MatExpr& e1, const MatExpr& e2, MatExpr& res) co
     double alpha1 = i1 ? 1 : e1.alpha, alpha2 = i2 ? 1 : e2.alpha;
 
     if( isMatProd(e1) && (i2 || isScaled(e2) || isT(e2)) )
-        MatOp_GEMM::makeExpr(res, (e1.flags & ~CV_GEMM_C_T)|(isT(e2) ? CV_GEMM_C_T : 0),
+        MatOp_GEMM::makeExpr(res, (e1.flags & ~cv::GEMM_3_T)|(isT(e2) ? cv::GEMM_3_T : 0),
                              e1.a, e1.b, alpha1, e2.a, -alpha2);
     else if( isMatProd(e2) && (i1 || isScaled(e1) || isT(e1)) )
-        MatOp_GEMM::makeExpr(res, (e2.flags & ~CV_GEMM_C_T)|(isT(e1) ? CV_GEMM_C_T : 0),
+        MatOp_GEMM::makeExpr(res, (e2.flags & ~cv::GEMM_3_T)|(isT(e1) ? cv::GEMM_3_T : 0),
                             e2.a, e2.b, -alpha2, e1.a, alpha1);
     else if( this == e2.op )
         MatOp::subtract(e1, e2, res);
@@ -1618,9 +1618,9 @@ void MatOp_GEMM::transpose(const MatExpr& e, MatExpr& res) const
     CV_INSTRUMENT_REGION();
 
     res = e;
-    res.flags = (!(e.flags & CV_GEMM_A_T) ? CV_GEMM_B_T : 0) |
-                (!(e.flags & CV_GEMM_B_T) ? CV_GEMM_A_T : 0) |
-                (!(e.flags & CV_GEMM_C_T) ? CV_GEMM_C_T : 0);
+    res.flags = (!(e.flags & cv::GEMM_1_T) ? cv::GEMM_2_T : 0) |
+                (!(e.flags & cv::GEMM_2_T) ? cv::GEMM_1_T : 0) |
+                (!(e.flags & cv::GEMM_3_T) ? cv::GEMM_3_T : 0);
     swap(res.a, res.b);
 }