build: fix/eliminate MSVC warnings

modules/calib3d/test/test_cameracalibration.cpp

@@ -1793,8 +1793,8 @@ double CV_StereoCalibrationTest_CPP::calibrateStereoCamera( const vector<vector<
 
     for (size_t i = 0; i < numImgs; i++)
     {
-        perViewErrors1[i] = perViewErrorsMat.at<double>(i, 0);
-        perViewErrors2[i] = perViewErrorsMat.at<double>(i, 1);
+        perViewErrors1[i] = perViewErrorsMat.at<double>((int)i, 0);
+        perViewErrors2[i] = perViewErrorsMat.at<double>((int)i, 1);
     }
 
     if (rotationMatrices.size() != numImgs)

modules/calib3d/test/test_fisheye.cpp

@@ -906,7 +906,7 @@ TEST_F(fisheyeTest, stereoCalibrateWithPerViewTransformations)
 
     std::vector<cv::Point2d> reprojectedImgPts[2] = {std::vector<cv::Point2d>(n_images), std::vector<cv::Point2d>(n_images)};
     size_t totalPoints = 0;
-    float totalMSError[2] = { 0, 0 }, viewMSError[2];
+    double totalMSError[2] = { 0, 0 };
     for( size_t i = 0; i < n_images; i++ )
     {
         cv::Matx33d viewRotMat1, viewRotMat2;
@@ -929,8 +929,10 @@ TEST_F(fisheyeTest, stereoCalibrateWithPerViewTransformations)
         cv::fisheye::projectPoints(objectPoints[i], reprojectedImgPts[0], viewRotVec1, viewT1, K1, D1, alpha1);
         cv::fisheye::projectPoints(objectPoints[i], reprojectedImgPts[1], viewRotVec2, viewT2, K2, D2, alpha2);
 
-        viewMSError[0] = cv::norm(leftPoints[i], reprojectedImgPts[0], cv::NORM_L2SQR);
-        viewMSError[1] = cv::norm(rightPoints[i], reprojectedImgPts[1], cv::NORM_L2SQR);
+        double viewMSError[2] = {
+            cv::norm(leftPoints[i], reprojectedImgPts[0], cv::NORM_L2SQR),
+            cv::norm(rightPoints[i], reprojectedImgPts[1], cv::NORM_L2SQR)
+        };
 
         size_t n = objectPoints[i].size();
         totalMSError[0] += viewMSError[0];

modules/core/include/opencv2/core/types.hpp

@@ -57,6 +57,11 @@
 #include "opencv2/core/cvstd.hpp"
 #include "opencv2/core/matx.hpp"
 
+#ifdef _MSC_VER
+#pragma warning(push)
+#pragma warning(disable: 4459)  // declaration of '...' hides global declaration
+#endif
+
 namespace cv
 {
 
@@ -2445,4 +2450,8 @@ TermCriteria::TermCriteria(int _type, int _maxCount, double _epsilon)
 
 } // cv
 
+#ifdef _MSC_VER
+#pragma warning(pop)
+#endif
+
 #endif //OPENCV_CORE_TYPES_HPP

modules/core/test/test_intrin_utils.hpp

@@ -1081,7 +1081,7 @@ template<typename R> struct TheTest
         typedef typename VTraits<uint_reg>::lane_type uint_type;
 
         Data<R> dataA, dataB(0), dataC, dataD(1), dataE(2);
-        dataA[0] = std::numeric_limits<int_type>::max();
+        dataA[0] = (LaneType)std::numeric_limits<int_type>::max();
         dataA[1] *= (LaneType)-1;
         union
         {

modules/gapi/include/opencv2/gapi/ocl/goclkernel.hpp

@@ -153,6 +153,10 @@ struct tracked_cv_umat{
     }
 };
 
+#ifdef _MSC_VER
+#pragma warning(push)
+#pragma warning(disable: 4702)  // unreachable code
+#endif
 template<typename... Outputs>
 void postprocess_ocl(Outputs&... outs)
 {
@@ -166,6 +170,9 @@ void postprocess_ocl(Outputs&... outs)
     int dummy[] = { 0, (validate(&outs), 0)... };
     cv::util::suppress_unused_warning(dummy);
 }
+#ifdef _MSC_VER
+#pragma warning(pop)
+#endif
 
 template<class T> struct ocl_get_out;
 template<> struct ocl_get_out<cv::GMat>

modules/gapi/src/streaming/onevpl/default.cpp

@@ -41,7 +41,6 @@ namespace onevpl {
 std::shared_ptr<IDeviceSelector> getDefaultDeviceSelector(const std::vector<CfgParam>&) {
     std::cerr << "Cannot utilize getDefaultVPLDeviceAndCtx without HAVE_ONEVPL enabled" << std::endl;
     util::throw_error(std::logic_error("Cannot utilize getDefaultVPLDeviceAndCtx without HAVE_ONEVPL enabled"));
-    return nullptr;
 }
 
 } // namespace onevpl

modules/objdetect/src/qrcode.cpp

@@ -2294,8 +2294,8 @@ static inline std::pair<int, int> matchPatternPoints(const vector<Point> &finder
             const float tmp = normL2Sqr<float>(Point2f(finderPattern[i]) - cornerPointsQR[j]);
             if (tmp < distanceToOrig) {
                 distanceToOrig = tmp;
-                closestFinderPatternV = i;
-                closetOriginalV = j;
+                closestFinderPatternV = (int)i;
+                closetOriginalV = (int)j;
             }
         }
     }
@@ -2550,15 +2550,15 @@ bool QRDecode::versionDefinition()
 
     if (useCode) {
         CV_LOG_INFO(NULL, "Version type: useCode");
-        version = versionByCode;
+        version = (uint8_t)versionByCode;
     }
     else if (useFinderPattern ) {
         CV_LOG_INFO(NULL, "Version type: useFinderPattern");
-        version = cvRound(versionByFinderPattern);
+        version = (uint8_t)cvRound(versionByFinderPattern);
     }
     else {
         CV_LOG_INFO(NULL, "Version type: useTransition");
-        version = versionByTransition;
+        version = (uint8_t)versionByTransition;
     }
     version_size = 21 + (version - 1) * 4;
     if ( !(0 < version && version <= 40) ) { return false; }

modules/video/src/tracking/tracker_nano.cpp

@@ -148,7 +148,7 @@ void TrackerNanoImpl::generateGrids()
 
     for (int i = 0; i < sz; i++)
     {
-        x1Vec[i] = i - sz2;
+        x1Vec[i] = (float)(i - sz2);
     }
 
     Mat x1M(1, sz, CV_32FC1, x1Vec.data());
@@ -202,9 +202,9 @@ void TrackerNanoImpl::getSubwindow(Mat& dstCrop, Mat& srcImg, int originalSz, in
     Size imgSz = srcImg.size();
     int c = (originalSz + 1) / 2;
 
-    int context_xmin = targetPos[0] - c;
+    int context_xmin = (int)(targetPos[0]) - c;
     int context_xmax = context_xmin + originalSz - 1;
-    int context_ymin = targetPos[1] - c;
+    int context_ymin = (int)(targetPos[1]) - c;
     int context_ymax = context_ymin + originalSz - 1;
 
     int left_pad = std::max(0, -context_xmin);
@@ -236,7 +236,7 @@ void TrackerNanoImpl::getSubwindow(Mat& dstCrop, Mat& srcImg, int originalSz, in
 bool TrackerNanoImpl::update(InputArray image_, Rect &boundingBoxRes)
 {
     image = image_.getMat().clone();
-    int targetSzSum = targetSz[0] + targetSz[1];
+    int targetSzSum = (int)(targetSz[0] + targetSz[1]);
 
     float wc = targetSz[0] + trackState.contextAmount * targetSzSum;
     float hc = targetSz[1] + trackState.contextAmount * targetSzSum;