Changed cv::log to std::log

modules/imgproc/src/histogram.cpp

@@ -2335,7 +2335,7 @@ double cv::compareHist( InputArray _H1, InputArray _H2, int method )
                 if(  fabs(q) <= DBL_EPSILON ) {
                     q = 1e-10;
                 }
-                result += p * cv::log( p / q );
+                result += p * std::log( p / q );
             }
         }
         else
@@ -2462,7 +2462,7 @@ double cv::compareHist( const SparseMat& H1, const SparseMat& H2, int method )
             double v2 = PH2->value<float>(node->idx, (size_t*)&node->hashval);
             if( !v2 )
                 v2 = 1e-10;
-            result += v1 * cv::log( v1 / v2 );
+            result += v1 * std::log( v1 / v2 );
         }
     }
     else

modules/imgproc/test/test_histograms.cpp

@@ -1058,7 +1058,7 @@ int CV_CompareHistTest::validate_test_results( int /*test_case_idx*/ )
                 continue;
             if (!v1)
                 v1 = 1e-10;
-            result0[CV_COMP_KL_DIV] += v0 * cv::log( v0 / v1 );
+            result0[CV_COMP_KL_DIV] += v0 * std::log( v0 / v1 );
             }
         }