Merge pull request #18419 from TolyaTalamanov:at/generic-inference

[G-API] Introduce generic version for cv::gapi::infer

* Introduce generic infer

* Move Generic to infer.hpp

* Removew num_outs

* Fix windows warnings

* Fix comments to review

* Fix doxygen

* Add comment

* Fix comments to review

* standoalone ifdef in ginfer.cpp

* Fix test

modules/gapi/src/api/gcall.cpp

@@ -78,3 +78,13 @@ const cv::GCall::Priv& cv::GCall::priv() const
 {
     return *m_priv;
 }
+
+cv::GKernel& cv::GCall::kernel()
+{
+    return m_priv->m_k;
+}
+
+cv::util::any& cv::GCall::params()
+{
+    return m_priv->m_params;
+}

modules/gapi/src/api/gcall_priv.hpp

@@ -42,10 +42,11 @@ class GCall::Priv
 {
 public:
     std::vector<GArg> m_args;
-    const GKernel     m_k;
+    GKernel     m_k;
 
     // TODO: Rename to "constructionNode" or smt to reflect its lifetime
     GNode             m_node;
+    cv::util::any     m_params;
 
     explicit Priv(const GKernel &k);
 };

modules/gapi/src/api/ginfer.cpp

@@ -25,3 +25,33 @@ std::vector<cv::gapi::GBackend> cv::gapi::GNetPackage::backends() const {
     for (const auto &nn : networks) unique_set.insert(nn.backend);
     return std::vector<cv::gapi::GBackend>(unique_set.begin(), unique_set.end());
 }
+
+// FIXME: Inference API is currently only available in full mode
+#if !defined(GAPI_STANDALONE)
+
+cv::GMat& cv::GInferInputs::operator[](const std::string& name) {
+    return in_blobs[name];
+}
+
+const std::unordered_map<std::string, cv::GMat>& cv::GInferInputs::getBlobs() const {
+    return in_blobs;
+}
+
+cv::GInferOutputs::GInferOutputs(std::shared_ptr<cv::GCall> call)
+    : m_call(std::move(call)), m_info(cv::util::any_cast<InOutInfo>(&m_call->params()))
+{
+};
+
+cv::GMat cv::GInferOutputs::at(const std::string& name)
+{
+    auto it = out_blobs.find(name);
+    if (it == out_blobs.end()) {
+        // FIXME: Avoid modifying GKernel
+        m_call->kernel().outShapes.push_back(cv::GShape::GMAT);
+        int out_idx = static_cast<int>(out_blobs.size());
+        it = out_blobs.emplace(name, m_call->yield(out_idx)).first;
+        m_info->out_names.push_back(name);
+    }
+    return it->second;
+};
+#endif // GAPI_STANDALONE