Fix spelling typos

backport commit 659ffaddb4

modules/features2d/include/opencv2/features2d.hpp

@@ -385,7 +385,7 @@ code which is distributed under GPL.
 class CV_EXPORTS_W MSER : public Feature2D
 {
 public:
-    /** @brief Full consturctor for %MSER detector
+    /** @brief Full constructor for %MSER detector
 
     @param _delta it compares \f$(size_{i}-size_{i-delta})/size_{i-delta}\f$
     @param _min_area prune the area which smaller than minArea

modules/features2d/src/kaze/nldiffusion_functions.h

@@ -36,7 +36,7 @@ void image_derivatives_scharr(const cv::Mat& src, cv::Mat& dst, int xorder, int
 // Nonlinear diffusion filtering scalar step
 void nld_step_scalar(cv::Mat& Ld, const cv::Mat& c, cv::Mat& Lstep, float stepsize);
 
-// For non-maxima suppresion
+// For non-maxima suppression
 bool check_maximum_neighbourhood(const cv::Mat& img, int dsize, float value, int row, int col, bool same_img);
 
 // Image downsampling

modules/features2d/src/mser.cpp

@@ -983,7 +983,7 @@ extractMSER_8uC3( const Mat& src,
                     double s = (double)(lr->size-lr->sizei)/(lr->dt-lr->di);
                     if ( s < lr->s )
                     {
-                        // skip the first one and check stablity
+                        // skip the first one and check stability
                         if ( i > lr->reinit+1 && MSCRStableCheck( lr, params ) )
                         {
                             if ( lr->tmsr == NULL )