Intel Inference Engine deep learning backend (#10608)

* Intel Inference Engine deep learning backend.

* OpenFace network using Inference Engine backend

modules/dnn/src/layers/permute_layer.cpp

@@ -42,6 +42,7 @@
 
 #include "../precomp.hpp"
 #include "layers_common.hpp"
+#include "op_inf_engine.hpp"
 #include <float.h>
 #include <algorithm>
 #include "opencl_kernels_dnn.hpp"
@@ -112,6 +113,12 @@ public:
         checkNeedForPermutation();
     }
 
+    virtual bool supportBackend(int backendId)
+    {
+        return backendId == DNN_BACKEND_DEFAULT ||
+               backendId == DNN_BACKEND_INFERENCE_ENGINE && haveInfEngine();
+    }
+
     bool getMemoryShapes(const std::vector<MatShape> &inputs,
                          const int requiredOutputs,
                          std::vector<MatShape> &outputs,
@@ -370,6 +377,25 @@ public:
         }
     }
 
+    virtual Ptr<BackendNode> initInfEngine(const std::vector<Ptr<BackendWrapper> >&)
+    {
+#ifdef HAVE_INF_ENGINE
+        InferenceEngine::LayerParams lp;
+        lp.name = name;
+        lp.type = "Permute";
+        lp.precision = InferenceEngine::Precision::FP32;
+        std::shared_ptr<InferenceEngine::CNNLayer> ieLayer(new InferenceEngine::CNNLayer(lp));
+
+        CV_Assert(!_order.empty());
+        ieLayer->params["order"] = format("%d", _order[0]);
+        for (int i = 1; i < _order.size(); ++i)
+            ieLayer->params["order"] += format(",%d", _order[i]);
+
+        return Ptr<BackendNode>(new InfEngineBackendNode(ieLayer));
+#endif  // HAVE_INF_ENGINE
+        return Ptr<BackendNode>();
+    }
+
     size_t _count;
     std::vector<size_t> _order;