Added dnnBackend option for the dnn-based detectors

Author: Nuzhny007

CMakeLists.txt

@@ -35,4 +35,3 @@ option(BUILD_CARS_COUNTING "Should compiled Cars counting example?" OFF)
 if (BUILD_CARS_COUNTING)
     add_subdirectory(cars_counting)
 endif(BUILD_CARS_COUNTING)
-                                  

example/VideoExample.h

@@ -375,6 +375,8 @@ class SSDMobileNetExample : public VideoExample
         config["confidenceThreshold"] = "0.5";
         config["maxCropRatio"] = "3.0";
         config["dnnTarget"] = "DNN_TARGET_OPENCL_FP16";
+        config["dnnBackend"] = "DNN_BACKEND_INFERENCE_ENGINE";
+
         m_detector = std::unique_ptr<BaseDetector>(CreateDetector(tracking::Detectors::SSD_MobileNet, config, m_useLocalTracking, frame));
         if (!m_detector.get())
         {
@@ -489,6 +491,7 @@ class YoloExample : public VideoExample
         config["confidenceThreshold"] = "0.1";
         config["maxCropRatio"] = "2.0";
         config["dnnTarget"] = "DNN_TARGET_OPENCL";
+        config["dnnBackend"] = "DNN_BACKEND_INFERENCE_ENGINE";
 
         m_detector = std::unique_ptr<BaseDetector>(CreateDetector(tracking::Detectors::Yolo, config, m_useLocalTracking, frame));
         if (!m_detector.get())

src/Detector/SSDMobileNetDetector.cpp

@@ -61,8 +61,26 @@ bool SSDMobileNetDetector::Init(const config_t& config)
         {
             m_net.setPreferableTarget(target->second);
         }
+    }
 
+#if (CV_VERSION_MAJOR >= 4)
+    auto dnnBackend = config.find("dnnBackend");
+    if (dnnBackend != config.end())
+    {
+        std::map<std::string, cv::dnn::Backend> backends;
+        backends["DNN_BACKEND_DEFAULT"] = cv::dnn::DNN_BACKEND_DEFAULT;
+        backends["DNN_BACKEND_HALIDE"] = cv::dnn::DNN_BACKEND_HALIDE;
+        backends["DNN_BACKEND_INFERENCE_ENGINE"] = cv::dnn::DNN_BACKEND_INFERENCE_ENGINE;
+        backends["DNN_BACKEND_OPENCV"] = cv::dnn::DNN_BACKEND_OPENCV;
+        backends["DNN_BACKEND_VKCOM"] = cv::dnn::DNN_BACKEND_VKCOM;
+
+        auto backend = backends.find(dnnTarget->second);
+        if (backend != std::end(backends))
+        {
+            m_net.setPreferableBackend(backend->second);
+        }
     }
+#endif
 
     auto confidenceThreshold = config.find("confidenceThreshold");
     if (confidenceThreshold != config.end())

src/Detector/YoloDetector.cpp

@@ -63,6 +63,25 @@ bool YoloDetector::Init(const config_t& config)
         }
     }
 
+#if (CV_VERSION_MAJOR >= 4)
+    auto dnnBackend = config.find("dnnBackend");
+    if (dnnBackend != config.end())
+    {
+        std::map<std::string, cv::dnn::Backend> backends;
+        backends["DNN_BACKEND_DEFAULT"] = cv::dnn::DNN_BACKEND_DEFAULT;
+        backends["DNN_BACKEND_HALIDE"] = cv::dnn::DNN_BACKEND_HALIDE;
+        backends["DNN_BACKEND_INFERENCE_ENGINE"] = cv::dnn::DNN_BACKEND_INFERENCE_ENGINE;
+        backends["DNN_BACKEND_OPENCV"] = cv::dnn::DNN_BACKEND_OPENCV;
+        backends["DNN_BACKEND_VKCOM"] = cv::dnn::DNN_BACKEND_VKCOM;
+
+        auto backend = backends.find(dnnTarget->second);
+        if (backend != std::end(backends))
+        {
+            m_net.setPreferableBackend(backend->second);
+        }
+    }
+#endif
+
     auto classNames = config.find("classNames");
     if (classNames != config.end())
     {