Merge pull request #15234 from alalek:backport

cmake/OpenCVModule.cmake

@@ -850,7 +850,7 @@ macro(ocv_create_module)
     set(the_module_target ${the_module})
   endif()
 
-  if(WINRT)
+  if(WINRT AND BUILD_TESTS)
     # removing APPCONTAINER from modules to run from console
     # in case of usual starting of WinRT test apps output is missing
     # so starting of console version w/o APPCONTAINER is required to get test results

doc/js_tutorials/js_setup/js_setup/js_setup.markdown

@@ -7,6 +7,9 @@ Installing Emscripten
 
 [Emscripten](https://github.com/kripken/emscripten) is an LLVM-to-JavaScript compiler. We will use Emscripten to build OpenCV.js.
 
+@note
+While this describes installation of required tools from scratch, there's a section below also describing an alternative procedure to perform the same build using docker containers which is often easier.
+
 To Install Emscripten, follow instructions of [Emscripten SDK](https://kripken.github.io/emscripten-site/docs/getting_started/downloads.html).
 
 For example:
@@ -103,3 +106,25 @@ Building OpenCV.js from Source
 
     @note
     It requires `node` installed in your development environment.
+
+Building OpenCV.js with Docker
+---------------------------------------
+
+Alternatively, the same build can be can be accomplished using [docker](https://www.docker.com/) containers which is often easier and more reliable, particularly in non linux systems. You only need to install [docker](https://www.docker.com/) on your system and use a popular container that provides a clean well tested environment for emscripten builds like this, that already has latest versions of all the necessary tools installed.
+
+So, make sure [docker](https://www.docker.com/) is installed in your system and running. The following shell script should work in linux and MacOS:
+
+@code{.bash}
+git clone https://github.com/opencv/opencv.git
+cd opencv
+docker run --rm --workdir /code -v "$PWD":/code "trzeci/emscripten:latest" python ./platforms/js/build_js.py build_js
+@endcode
+
+In Windows use the following PowerShell command:
+
+@code{.bash}
+docker run --rm --workdir /code -v "$(get-location):/code" "trzeci/emscripten:latest" python ./platforms/js/build_js.py build_js
+@endcode
+
+@note
+The example uses latest version of [trzeci/emscripten](https://hub.docker.com/r/trzeci/emscripten) docker container. At this time, the latest version works fine and is `trzeci/emscripten:sdk-tag-1.38.32-64bit`

modules/core/src/utils/datafile.cpp

@@ -108,7 +108,7 @@ static cv::String getModuleLocation(const void* addr)
     CV_UNUSED(addr);
 #ifdef _WIN32
     HMODULE m = 0;
-#if _WIN32_WINNT >= 0x0501
+#if _WIN32_WINNT >= 0x0501 && (!defined(WINAPI_FAMILY) || (WINAPI_FAMILY == WINAPI_FAMILY_DESKTOP_APP))
     ::GetModuleHandleEx(GET_MODULE_HANDLE_EX_FLAG_FROM_ADDRESS | GET_MODULE_HANDLE_EX_FLAG_UNCHANGED_REFCOUNT,
         reinterpret_cast<LPCTSTR>(addr),
         &m);

modules/flann/include/opencv2/flann/dist.h

@@ -441,7 +441,7 @@ struct Hamming
             result = vgetq_lane_s32 (vreinterpretq_s32_u64(bitSet2),0);
             result += vgetq_lane_s32 (vreinterpretq_s32_u64(bitSet2),2);
         }
-#elif __GNUC__
+#elif defined(__GNUC__)
         {
             //for portability just use unsigned long -- and use the __builtin_popcountll (see docs for __builtin_popcountll)
             typedef unsigned long long pop_t;

modules/highgui/src/roiSelector.cpp

@@ -106,10 +106,10 @@ class ROISelector
         bool isDrawing;
         Rect2d box;
         Mat image;
+        Point2f startPos;
 
         // parameters for drawing from the center
         bool drawFromCenter;
-        Point2f center;
 
         // initializer list
         handlerT() : isDrawing(false), drawFromCenter(true){};
@@ -136,19 +136,31 @@ class ROISelector
             {
                 if (selectorParams.drawFromCenter)
                 {
-                    selectorParams.box.width = 2 * (x - selectorParams.center.x);
-                    selectorParams.box.height = 2 * (y - selectorParams.center.y);
-                    selectorParams.box.x = std::min(
-                                std::max(selectorParams.center.x - selectorParams.box.width / 2.0, 0.), (double)imageSize.width);
-                    selectorParams.box.y = std::min(
-                                std::max(selectorParams.center.y - selectorParams.box.height / 2.0, 0.), (double)imageSize.height);
+                    // limit half extends to imageSize
+                    float halfWidth = std::min(std::min(
+                            std::abs(x - selectorParams.startPos.x),
+                            selectorParams.startPos.x),
+                            imageSize.width - selectorParams.startPos.x);
+                    float halfHeight = std::min(std::min(
+                            std::abs(y - selectorParams.startPos.y),
+                            selectorParams.startPos.y),
+                            imageSize.height - selectorParams.startPos.y);
+
+                    selectorParams.box.width = halfWidth * 2;
+                    selectorParams.box.height = halfHeight * 2;
+                    selectorParams.box.x = selectorParams.startPos.x - halfWidth;
+                    selectorParams.box.y = selectorParams.startPos.y - halfHeight;
+
                 }
                 else
                 {
-                    selectorParams.box.width = std::max(
-                                std::min(x - selectorParams.box.x, (double)imageSize.width - selectorParams.box.x), - selectorParams.box.x);
-                    selectorParams.box.height = std::max(
-                                std::min(y - selectorParams.box.y, (double)imageSize.height - selectorParams.box.y), - selectorParams.box.y);
+                    // limit x and y to imageSize
+                    int lx = std::min(std::max(x, 0), imageSize.width);
+                    int by = std::min(std::max(y, 0), imageSize.height);
+                    selectorParams.box.width = std::abs(lx - selectorParams.startPos.x);
+                    selectorParams.box.height = std::abs(by - selectorParams.startPos.y);
+                    selectorParams.box.x = std::min((float)lx, selectorParams.startPos.x);
+                    selectorParams.box.y = std::min((float)by, selectorParams.startPos.y);
                 }
             }
             break;
@@ -157,7 +169,7 @@ class ROISelector
         case EVENT_LBUTTONDOWN:
             selectorParams.isDrawing = true;
             selectorParams.box = Rect2d(x, y, 0, 0);
-            selectorParams.center = Point2f((float)x, (float)y);
+            selectorParams.startPos = Point2f((float)x, (float)y);
             break;
 
         // cleaning up the selected bounding box

modules/videoio/src/cap_ffmpeg.cpp

@@ -80,7 +80,7 @@ static cv::Mutex _icvInitFFMPEG_mutex;
 static const HMODULE cv_GetCurrentModule()
 {
     HMODULE h = 0;
-#if _WIN32_WINNT >= 0x0501
+#if _WIN32_WINNT >= 0x0501 && (!defined(WINAPI_FAMILY) || (WINAPI_FAMILY == WINAPI_FAMILY_DESKTOP_APP))
     ::GetModuleHandleEx(GET_MODULE_HANDLE_EX_FLAG_FROM_ADDRESS | GET_MODULE_HANDLE_EX_FLAG_UNCHANGED_REFCOUNT,
         reinterpret_cast<LPCTSTR>(cv_GetCurrentModule),
         &h);

modules/videoio/src/cap_winrt/CaptureFrameGrabber.cpp

@@ -94,7 +94,7 @@ Media::CaptureFrameGrabber::~CaptureFrameGrabber()
 
 void Media::CaptureFrameGrabber::ShowCameraSettings()
 {
-#if WINAPI_FAMILY!=WINAPI_FAMILY_PHONE_APP
+#if (WINAPI_FAMILY != WINAPI_FAMILY_PHONE_APP) && (WINAPI_FAMILY != WINAPI_FAMILY_PC_APP)
     if (_state == State::Started)
     {
         CameraOptionsUI::Show(_capture.Get());