ocl: add support for initialization from user-provided OpenCL handles

modules/ocl/CMakeLists.txt

@@ -5,4 +5,7 @@ endif()
 
 set(the_description "OpenCL-accelerated Computer Vision")
 ocv_define_module(ocl opencv_core opencv_imgproc opencv_features2d opencv_objdetect opencv_video opencv_calib3d opencv_ml "${OPENCL_LIBRARIES}")
+if(TARGET opencv_test_ocl)
+  target_link_libraries(opencv_test_ocl "${OPENCL_LIBRARIES}")
+endif()
 ocv_warnings_disable(CMAKE_CXX_FLAGS -Wshadow)

modules/ocl/doc/structures_and_utility_functions.rst

@@ -25,12 +25,26 @@ Returns the list of devices
 
 ocl::setDevice
 --------------
-Returns void
+Initialize OpenCL computation context
 
 .. ocv:function:: void ocl::setDevice( const DeviceInfo* info )
 
     :param info: device info
 
+ocl::initializeContext
+--------------------------------
+Alternative way to initialize OpenCL computation context.
+
+.. ocv:function:: void ocl::initializeContext(void* pClPlatform, void* pClContext, void* pClDevice)
+
+    :param pClPlatform: selected ``platform_id`` (via pointer, parameter type is ``cl_platform_id*``)
+
+    :param pClContext: selected ``cl_context`` (via pointer, parameter type is ``cl_context*``)
+
+    :param pClDevice: selected ``cl_device_id`` (via pointer, parameter type is ``cl_device_id*``)
+
+This function can be used for context initialization with D3D/OpenGL interoperability.
+
 ocl::setBinaryPath
 ------------------
 Returns void

modules/ocl/include/opencv2/ocl/ocl.hpp

@@ -118,6 +118,7 @@ namespace cv
             const PlatformInfo* platform;
 
             DeviceInfo();
+            ~DeviceInfo();
         };
 
         struct PlatformInfo
@@ -136,6 +137,7 @@ namespace cv
             std::vector<const DeviceInfo*> devices;
 
             PlatformInfo();
+            ~PlatformInfo();
         };
 
         //////////////////////////////// Initialization & Info ////////////////////////
@@ -151,6 +153,10 @@ namespace cv
         // set device you want to use
         CV_EXPORTS void setDevice(const DeviceInfo* info);
 
+        // Initialize from OpenCL handles directly.
+        // Argument types is (pointers): cl_platform_id*, cl_context*, cl_device_id*
+        CV_EXPORTS void initializeContext(void* pClPlatform, void* pClContext, void* pClDevice);
+
         //////////////////////////////// Error handling ////////////////////////
         CV_EXPORTS void error(const char *error_string, const char *file, const int line, const char *func);
 

modules/ocl/test/test_api.cpp

@@ -40,7 +40,7 @@
 //M*/
 
 #include "test_precomp.hpp"
-#include "opencv2/ocl/cl_runtime/cl_runtime.hpp" // for OpenCL types: cl_mem
+#include "opencv2/ocl/cl_runtime/cl_runtime.hpp" // for OpenCL types & functions
 
 TEST(TestAPI, openCLExecuteKernelInterop)
 {
@@ -78,3 +78,87 @@ TEST(TestAPI, openCLExecuteKernelInterop)
 
     EXPECT_LE(checkNorm(cpuMat, dst), 1e-3);
 }
+
+// This test must be DISABLED by default!
+// (We can't restore original context for other tests)
+TEST(TestAPI, DISABLED_InitializationFromHandles)
+{
+#define MAX_PLATFORMS 16
+    cl_platform_id platforms[MAX_PLATFORMS] = { NULL };
+    cl_uint numPlatforms = 0;
+    cl_int status = ::clGetPlatformIDs(MAX_PLATFORMS, &platforms[0], &numPlatforms);
+    ASSERT_EQ(CL_SUCCESS, status) << "clGetPlatformIDs";
+    ASSERT_NE(0, (int)numPlatforms);
+
+    int selectedPlatform = 0;
+    cl_platform_id platform = platforms[selectedPlatform];
+
+    ASSERT_NE((void*)NULL, platform);
+
+    cl_device_id device = NULL;
+    status = ::clGetDeviceIDs(platform, CL_DEVICE_TYPE_ALL, 1, &device, NULL);
+    ASSERT_EQ(CL_SUCCESS, status) << "clGetDeviceIDs";
+    ASSERT_NE((void*)NULL, device);
+
+    cl_context_properties cps[3] = { CL_CONTEXT_PLATFORM, (cl_context_properties)(platform), 0 };
+    cl_context context = ::clCreateContext(cps, 1, &device, NULL, NULL, &status);
+    ASSERT_EQ(CL_SUCCESS, status) << "clCreateContext";
+    ASSERT_NE((void*)NULL, context);
+
+    ASSERT_NO_THROW(cv::ocl::initializeContext(&platform, &context, &device));
+
+    status = ::clReleaseContext(context);
+    ASSERT_EQ(CL_SUCCESS, status) << "clReleaseContext";
+
+#ifdef CL_VERSION_1_2
+#if 1
+    {
+        cv::ocl::Context* ctx = cv::ocl::Context::getContext();
+        ASSERT_NE((void*)NULL, ctx);
+        if (ctx->supportsFeature(cv::ocl::FEATURE_CL_VER_1_2)) // device supports OpenCL 1.2+
+        {
+            status = ::clReleaseDevice(device);
+            ASSERT_EQ(CL_SUCCESS, status) << "clReleaseDevice";
+        }
+    }
+#else // code below doesn't work on Linux (SEGFAULTs on 1.1- devices are not handled via exceptions)
+    try
+    {
+        status = ::clReleaseDevice(device); // NOTE This works only with !DEVICES! that supports OpenCL 1.2
+        (void)status; // no check
+    }
+    catch (...)
+    {
+        // nothing, there is no problem
+    }
+#endif
+#endif
+
+    // print the name of current device
+    cv::ocl::Context* ctx = cv::ocl::Context::getContext();
+    ASSERT_NE((void*)NULL, ctx);
+    const cv::ocl::DeviceInfo& deviceInfo = ctx->getDeviceInfo();
+    std::cout << "Device name: " << deviceInfo.deviceName << std::endl;
+    std::cout << "Platform name: " << deviceInfo.platform->platformName << std::endl;
+
+    ASSERT_EQ(context, *(cl_context*)ctx->getOpenCLContextPtr());
+    ASSERT_EQ(device, *(cl_device_id*)ctx->getOpenCLDeviceIDPtr());
+
+    // do some calculations and check results
+    cv::RNG rng;
+    Size sz(100, 100);
+    cv::Mat srcMat = cvtest::randomMat(rng, sz, CV_32FC4, -10, 10, false);
+    cv::Mat dstMat;
+
+    cv::ocl::oclMat srcGpuMat(srcMat);
+    cv::ocl::oclMat dstGpuMat;
+
+    cv::Scalar v = cv::Scalar::all(1);
+    cv::add(srcMat, v, dstMat);
+    cv::ocl::add(srcGpuMat, v, dstGpuMat);
+
+    cv::Mat dstGpuMatMap;
+    dstGpuMat.download(dstGpuMatMap);
+
+    EXPECT_LE(checkNorm(dstMat, dstGpuMatMap), 1e-3);
+}