Merge remote-tracking branch 'upstream/master'

Conflicts:
	modules/calib3d/doc/camera_calibration_and_3d_reconstruction.rst

samples/cpp/tutorial_code/calib3d/camera_calibration/camera_calibration.cpp

@@ -7,6 +7,8 @@
 #include <opencv2/core/utility.hpp>
 #include <opencv2/imgproc.hpp>
 #include <opencv2/calib3d.hpp>
+#include <opencv2/imgcodecs.hpp>
+#include <opencv2/videoio.hpp>
 #include <opencv2/highgui.hpp>
 
 #ifndef _CRT_SECURE_NO_WARNINGS

samples/cpp/tutorial_code/calib3d/stereoBM/SBM_Sample.cpp

@@ -8,6 +8,7 @@
 #include <iostream>
 #include "opencv2/calib3d/calib3d.hpp"
 #include "opencv2/core/core.hpp"
+#include "opencv2/imgcodecs.hpp"
 #include "opencv2/highgui/highgui.hpp"
 
 using namespace cv;