Merge pull request #21268 from pccvlab:tf_Arg

add argmax and argmin parsing for tensorflow

* add argmax and argmin for tf

* remove whitespace

* remove whitespace

* remove static_cast

Signed-off-by: Crayon-new <1349159541@qq.com>

modules/dnn/src/tensorflow/tf_importer.cpp

@@ -599,6 +599,8 @@ private:
     void parseActivation         (tensorflow::GraphDef& net, const tensorflow::NodeDef& layer, LayerParams& layerParams);
     void parseExpandDims         (tensorflow::GraphDef& net, const tensorflow::NodeDef& layer, LayerParams& layerParams);
     void parseSquare             (tensorflow::GraphDef& net, const tensorflow::NodeDef& layer, LayerParams& layerParams);
+    void parseArg                (tensorflow::GraphDef& net, const tensorflow::NodeDef& layer, LayerParams& layerParams);
+
     void parseCustomLayer        (tensorflow::GraphDef& net, const tensorflow::NodeDef& layer, LayerParams& layerParams);
 };
 
@@ -677,6 +679,7 @@ const TFImporter::DispatchMap TFImporter::buildDispatchMap()
             dispatch["Elu"] = dispatch["Exp"] = dispatch["Identity"] = dispatch["Relu6"] = &TFImporter::parseActivation;
     dispatch["ExpandDims"] = &TFImporter::parseExpandDims;
     dispatch["Square"] = &TFImporter::parseSquare;
+    dispatch["ArgMax"] = dispatch["ArgMin"] = &TFImporter::parseArg;
 
     return dispatch;
 }
@@ -2624,6 +2627,22 @@ void TFImporter::parseActivation(tensorflow::GraphDef& net, const tensorflow::No
     connectToAllBlobs(layer_id, dstNet, parsePin(layer.input(0)), id, num_inputs);
 }
 
+void TFImporter::parseArg(tensorflow::GraphDef& net, const tensorflow::NodeDef& layer, LayerParams& layerParams)
+{
+    const std::string& name = layer.name();
+    const std::string& type = layer.op();
+
+    Mat dimension = getTensorContent(getConstBlob(layer, value_id, 1));
+    CV_Assert(dimension.total() == 1 && dimension.type() == CV_32SC1);
+    layerParams.set("axis", *dimension.ptr<int>());
+    layerParams.set("op", type == "ArgMax" ? "max" : "min");
+    layerParams.set("keepdims", false); //tensorflow doesn't have this atrr, the output's dims minus one(default);
+
+    int id = dstNet.addLayer(name, "Arg", layerParams);
+    layer_id[name] = id;
+    connect(layer_id, dstNet, parsePin(layer.input(0)), id, 0);
+}
+
 void TFImporter::parseCustomLayer(tensorflow::GraphDef& net, const tensorflow::NodeDef& layer, LayerParams& layerParams)
 {
     // Importer does not know how to map this TensorFlow's operation onto OpenCV's layer.

modules/dnn/test/test_tf_importer.cpp

@@ -185,6 +185,14 @@ TEST_P(Test_TensorFlow_layers, reduce_sum_channel_keep_dims)
     runTensorFlowNet("reduce_sum_channel", false, 0.0, 0.0, false, "_keep_dims");
 }
 
+TEST_P(Test_TensorFlow_layers, ArgLayer)
+{
+    if (backend != DNN_BACKEND_OPENCV || target != DNN_TARGET_CPU)
+        throw SkipTestException("Only CPU is supported");  // FIXIT use tags
+    runTensorFlowNet("argmax");
+    runTensorFlowNet("argmin");
+}
+
 TEST_P(Test_TensorFlow_layers, conv_single_conv)
 {
     runTensorFlowNet("single_conv");