OpenVX calls updated to use single common OpenVX context per thread

modules/core/include/opencv2/core/openvx/ovx_defs.hpp

@@ -20,6 +20,12 @@
 #define IVX_USE_OPENCV
 #include "ivx.hpp"
 
+namespace cv{
+namespace ovx{
+// Get common thread local OpenVX context
+CV_EXPORTS_W ivx::Context& getOpenVXContext();
+}}
+
 #define CV_OVX_RUN(condition, func, ...)          \
     if (cv::useOpenVX() && (condition) && func)   \
     {                                             \

modules/core/src/convert.cpp

@@ -4673,7 +4673,7 @@ static bool _openvx_cvt(const T* src, size_t sstep,
 
     try
     {
-        Context context = Context::create();
+        Context context = ovx::getOpenVXContext();
 
         // Other conversions are marked as "experimental"
         if(context.vendorID() == VX_ID_KHRONOS &&
@@ -5406,7 +5406,7 @@ static bool openvx_LUT(Mat src, Mat dst, Mat _lut)
 
     try
     {
-        ivx::Context ctx = ivx::Context::create();
+        ivx::Context ctx = ovx::getOpenVXContext();
 
         ivx::Image
             ia = ivx::Image::createFromHandle(ctx, VX_DF_IMAGE_U8,

modules/core/src/ovx.cpp

@@ -14,6 +14,38 @@
 namespace cv
 {
 
+namespace ovx
+{
+#ifdef HAVE_OPENVX
+
+// Simple TLSData<ivx::Context> doesn't work, because default constructor doesn't create any OpenVX context.
+struct OpenVXTLSData
+{
+    OpenVXTLSData() : ctx(ivx::Context::create()) {}
+    ivx::Context ctx;
+};
+
+static TLSData<OpenVXTLSData>& getOpenVXTLSData()
+{
+    CV_SINGLETON_LAZY_INIT_REF(TLSData<OpenVXTLSData>, new TLSData<OpenVXTLSData>())
+}
+
+struct OpenVXCleanupFunctor
+{
+    ~OpenVXCleanupFunctor() { getOpenVXTLSData().cleanup(); }
+};
+static OpenVXCleanupFunctor g_openvx_cleanup_functor;
+
+ivx::Context& getOpenVXContext()
+{
+    return getOpenVXTLSData().get()->ctx;
+}
+
+#endif
+
+} // namespace
+
+
 bool haveOpenVX()
 {
 #ifdef HAVE_OPENVX
@@ -22,7 +54,7 @@ bool haveOpenVX()
     {
         try
         {
-        ivx::Context context = ivx::Context::create();
+        ivx::Context context = ovx::getOpenVXContext();
         vx_uint16 vComp = ivx::compiledWithVersion();
         vx_uint16 vCurr = context.version();
         g_haveOpenVX =

modules/core/src/stat.cpp

@@ -1665,7 +1665,7 @@ namespace cv
 
         try
         {
-            ivx::Context ctx = ivx::Context::create();
+            ivx::Context ctx = ovx::getOpenVXContext();
 #ifndef VX_VERSION_1_1
             if (ctx.vendorID() == VX_ID_KHRONOS)
                 return false; // Do not use OpenVX meanStdDev estimation for sample 1.0.1 implementation due to lack of accuracy
@@ -2312,7 +2312,7 @@ static bool openvx_minMaxIdx(Mat &src, double* minVal, double* maxVal, int* minI
 
     try
     {
-        ivx::Context ctx = ivx::Context::create();
+        ivx::Context ctx = ovx::getOpenVXContext();
         ivx::Image
             ia = ivx::Image::createFromHandle(ctx, stype == CV_8UC1 ? VX_DF_IMAGE_U8 : VX_DF_IMAGE_S16,
                 ivx::Image::createAddressing(cols, rows, stype == CV_8UC1 ? 1 : 2, (vx_int32)(src.step[0])), src.ptr());