Fix windows build warnings

modules/core/test/test_operations.cpp

@@ -774,7 +774,7 @@ bool CV_OperationsTest::TestTemplateMat()
             Mat m2 = Mat::zeros(10, 10, CV_8UC3);
             m1.copyTo(m2.row(1));
         }
-        catch(const Exception& e)
+        catch(const Exception&)
         {
             badarg_catched = true;
         }

modules/gpu/perf/perf_imgproc.cpp

@@ -1739,7 +1739,7 @@ PERF_TEST_P(Method_Sz, ImgProc_GeneralizedHough, Combine(
     for (int i = 0; i < objCount; ++i)
     {
         double scale = rng.uniform(0.7, 1.3);
-        bool rotate = rng.uniform(0, 2);
+        bool rotate = 1 == rng.uniform(0, 2);
 
         cv::Mat obj;
         cv::resize(templ, obj, cv::Size(), scale, scale);

modules/imgproc/test/test_imgwarp_strict.cpp

@@ -433,7 +433,7 @@ void CV_Resize_Test::run_reference_func()
 
 double CV_Resize_Test::getWeight(double a, double b, int x)
 {
-    float w = std::min(static_cast<double>(x + 1), b) - std::max(static_cast<double>(x), a);
+    double w = std::min(static_cast<double>(x + 1), b) - std::max(static_cast<double>(x), a);
     CV_Assert(w >= 0);
     return w;
 }
@@ -514,7 +514,7 @@ void CV_Resize_Test::resize_1d(const Mat& _src, Mat& _dst, int dy, const dim& _d
     else if (interpolation == INTER_LINEAR || interpolation == INTER_CUBIC || interpolation == INTER_LANCZOS4)
     {
         internal::interpolate_method inter_func = internal::inter_array[interpolation - (interpolation == INTER_LANCZOS4 ? 2 : 1)];
-        int elemsize = _src.elemSize();
+        size_t elemsize = _src.elemSize();
         
         int ofs = 0, ksize = 2;
         if (interpolation == INTER_CUBIC)
@@ -557,10 +557,10 @@ void CV_Resize_Test::resize_1d(const Mat& _src, Mat& _dst, int dy, const dim& _d
 
 void CV_Resize_Test::generate_buffer(double scale, dim& _dim)
 {
-    int length = _dim.size();
-    for (int dx = 0; dx < length; ++dx)
+    size_t length = _dim.size();
+    for (size_t dx = 0; dx < length; ++dx)
     {            
-        double fsx = scale * (dx + 0.5f) - 0.5f;
+        double fsx = scale * (dx + 0.5) - 0.5;
         int isx = cvFloor(fsx);
         _dim[dx] = std::make_pair(isx, fsx - isx);
     }

samples/cpp/pca.cpp

@@ -176,7 +176,7 @@ int main(int argc, char** argv)
     // display until user presses q
     imshow(winName, reconstruction);
 
-    char key = 0;
+    int key = 0;
     while(key != 'q')
         key = waitKey();
 

samples/cpp/simpleflow_demo.cpp

@@ -86,7 +86,7 @@ static void run(int argc, char** argv) {
 
   Mat flow;
 
-  float start = getTickCount();
+  float start = (float)getTickCount();
   calcOpticalFlowSF(frame1, frame2, 
                     flow,
                     3, 2, 4, 4.1, 25.5, 18, 55.0, 25.5, 0.35, 18, 55.0, 25.5, 10);
@@ -156,7 +156,7 @@ static float calc_rmse(Mat flow1, Mat flow2) {
       }
     }
   }
-  return sqrt(sum / (1e-9 + counter));
+  return (float)sqrt(sum / (1e-9 + counter));
 }
 
 static void eval(int argc, char** argv) {