Merge remote-tracking branch 'upstream/3.4' into merge-3.4

samples/cpp/stitching_detailed.cpp

@@ -431,10 +431,11 @@ int main(int argc, char* argv[])
     {
         finder = xfeatures2d::SURF::create();
     }
-    else if (features_type == "sift") {
-        finder = xfeatures2d::SIFT::create();
-    }
 #endif
+    else if (features_type == "sift")
+    {
+        finder = SIFT::create();
+    }
     else
     {
         cout << "Unknown 2D features type: '" << features_type << "'.\n";

samples/cpp/tutorial_code/calib3d/real_time_pose_estimation/src/Utils.cpp

@@ -323,15 +323,8 @@ void createFeatures(const std::string &featureName, int numKeypoints, cv::Ptr<cv
     }
     else if (featureName == "SIFT")
     {
-#if defined (OPENCV_ENABLE_NONFREE) && defined (HAVE_OPENCV_XFEATURES2D)
-        detector = cv::xfeatures2d::SIFT::create();
-        descriptor = cv::xfeatures2d::SIFT::create();
-#else
-        std::cout << "xfeatures2d module is not available or nonfree is not enabled." << std::endl;
-        std::cout << "Default to ORB." << std::endl;
-        detector = cv::ORB::create(numKeypoints);
-        descriptor = cv::ORB::create(numKeypoints);
-#endif
+        detector = cv::SIFT::create();
+        descriptor = cv::SIFT::create();
     }
     else if (featureName == "SURF")
     {

samples/cpp/videocapture_basic.cpp

@@ -25,7 +25,7 @@ int main(int, char**)
     int deviceID = 0;             // 0 = open default camera
     int apiID = cv::CAP_ANY;      // 0 = autodetect default API
     // open selected camera using selected API
-    cap.open(deviceID + apiID);
+    cap.open(deviceID, apiID);
     // check if we succeeded
     if (!cap.isOpened()) {
         cerr << "ERROR! Unable to open camera\n";