IVGCVSW-2874 Add DequantizeLayer and no-op factory method

*Add Dequantize layer to the frontend
*Add Serializer and Deserializer for Dequantize

Change-Id: Ide2647b9e0348d599deb97e61ca4bf66e2f17fc0
Signed-off-by: Nattapat Chaimanowong <nattapat.chaimanowong@arm.com>

5 files changed, 65 insertions, 2 deletions

diff --git a/src/armnnSerializer/ArmnnSchema.fbs b/src/armnnSerializer/ArmnnSchema.fbs
index 7ac83598e1..3aa644dbe5 100644
--- a/src/armnnSerializer/ArmnnSchema.fbs
+++ b/src/armnnSerializer/ArmnnSchema.fbs
@@ -117,7 +117,8 @@ enum LayerType : uint {
     Splitter = 32,
     DetectionPostProcess = 33,
     Lstm = 34,
-    Quantize = 35
+    Quantize = 35,
+    Dequantize = 36
 }
 
 // Base layer table to be used as part of other layers
@@ -519,6 +520,10 @@ table LstmLayer {
     inputParams:LstmInputParams;
 }
 
+table DequantizeLayer {
+    base:LayerBase;
+}
+
 union Layer {
     ActivationLayer,
     AdditionLayer,
@@ -555,7 +560,8 @@ union Layer {
     SplitterLayer,
     DetectionPostProcessLayer,
     LstmLayer,
-    QuantizeLayer
+    QuantizeLayer,
+    DequantizeLayer
 }
 
 table AnyLayer {
diff --git a/src/armnnSerializer/Serializer.cpp b/src/armnnSerializer/Serializer.cpp
index 83777c9849..7181f01e6b 100644
--- a/src/armnnSerializer/Serializer.cpp
+++ b/src/armnnSerializer/Serializer.cpp
@@ -289,6 +289,15 @@ void SerializerVisitor::VisitDepthwiseConvolution2dLayer(const armnn::IConnectab
     CreateAnyLayer(flatBufferLayer.o, serializer::Layer::Layer_DepthwiseConvolution2dLayer);
 }
 
+void SerializerVisitor::VisitDequantizeLayer(const armnn::IConnectableLayer* layer,
+                                             const char* name)
+{
+    auto fbDequantizeBaseLayer = CreateLayerBase(layer, serializer::LayerType::LayerType_Dequantize);
+    auto fbDequantizeLayer     = serializer::CreateDequantizeLayer(m_flatBufferBuilder, fbDequantizeBaseLayer);
+
+    CreateAnyLayer(fbDequantizeLayer.o, serializer::Layer::Layer_DequantizeLayer);
+}
+
 void SerializerVisitor::VisitDetectionPostProcessLayer(const armnn::IConnectableLayer* layer,
                                                        const armnn::DetectionPostProcessDescriptor& descriptor,
                                                        const armnn::ConstTensor& anchors,
diff --git a/src/armnnSerializer/Serializer.hpp b/src/armnnSerializer/Serializer.hpp
index 82e19316e9..5c3e48a695 100644
--- a/src/armnnSerializer/Serializer.hpp
+++ b/src/armnnSerializer/Serializer.hpp
@@ -77,6 +77,9 @@ public:
                                           const armnn::Optional<armnn::ConstTensor>& biases,
                                           const char* name = nullptr) override;
 
+    void VisitDequantizeLayer(const armnn::IConnectableLayer* layer,
+                              const char* name = nullptr) override;
+
     void VisitDetectionPostProcessLayer(const armnn::IConnectableLayer* layer,
                                         const armnn::DetectionPostProcessDescriptor& descriptor,
                                         const armnn::ConstTensor& anchors,
diff --git a/src/armnnSerializer/SerializerSupport.md b/src/armnnSerializer/SerializerSupport.md
index 7686d5c24c..a3c5852bd2 100644
--- a/src/armnnSerializer/SerializerSupport.md
+++ b/src/armnnSerializer/SerializerSupport.md
@@ -13,6 +13,7 @@ The Arm NN SDK Serializer currently supports the following layers:
 * Constant
 * Convolution2d
 * DepthwiseConvolution2d
+* Dequantize
 * DetectionPostProcess
 * Division
 * Equal
diff --git a/src/armnnSerializer/test/SerializerTests.cpp b/src/armnnSerializer/test/SerializerTests.cpp
index 0345e53bcb..0979076476 100644
--- a/src/armnnSerializer/test/SerializerTests.cpp
+++ b/src/armnnSerializer/test/SerializerTests.cpp
@@ -59,6 +59,9 @@ protected:
             BOOST_TEST(connectedInfo.GetShape() == m_InputTensorInfos[i].GetShape());
             BOOST_TEST(
                 GetDataTypeName(connectedInfo.GetDataType()) == GetDataTypeName(m_InputTensorInfos[i].GetDataType()));
+
+            BOOST_TEST(connectedInfo.GetQuantizationScale() == m_InputTensorInfos[i].GetQuantizationScale());
+            BOOST_TEST(connectedInfo.GetQuantizationOffset() == m_InputTensorInfos[i].GetQuantizationOffset());
         }
 
         for (unsigned int i = 0; i < m_OutputTensorInfos.size(); i++)
@@ -67,6 +70,9 @@ protected:
             BOOST_TEST(outputInfo.GetShape() == m_OutputTensorInfos[i].GetShape());
             BOOST_TEST(
                 GetDataTypeName(outputInfo.GetDataType()) == GetDataTypeName(m_OutputTensorInfos[i].GetDataType()));
+
+            BOOST_TEST(outputInfo.GetQuantizationScale() == m_OutputTensorInfos[i].GetQuantizationScale());
+            BOOST_TEST(outputInfo.GetQuantizationOffset() == m_OutputTensorInfos[i].GetQuantizationOffset());
         }
     }
 
@@ -590,6 +596,44 @@ BOOST_AUTO_TEST_CASE(SerializeDepthwiseConvolution2d)
     deserializedNetwork->Accept(verifier);
 }
 
+BOOST_AUTO_TEST_CASE(SerializeDequantize)
+{
+    class DequantizeLayerVerifier : public LayerVerifierBase
+    {
+    public:
+        DequantizeLayerVerifier(const std::string& layerName,
+                                const std::vector<armnn::TensorInfo>& inputInfos,
+                                const std::vector<armnn::TensorInfo>& outputInfos)
+        : LayerVerifierBase(layerName, inputInfos, outputInfos) {}
+
+        void VisitDequantizeLayer(const armnn::IConnectableLayer* layer, const char* name) override
+        {
+            VerifyNameAndConnections(layer, name);
+        }
+    };
+
+    const std::string layerName("dequantize");
+    const armnn::TensorInfo inputInfo({ 1, 5, 2, 3 }, armnn::DataType::QuantisedAsymm8, 0.5f, 1);
+    const armnn::TensorInfo outputInfo({ 1, 5, 2, 3 }, armnn::DataType::Float32);
+
+    armnn::INetworkPtr network = armnn::INetwork::Create();
+    armnn::IConnectableLayer* const inputLayer = network->AddInputLayer(0);
+    armnn::IConnectableLayer* const dequantizeLayer = network->AddDequantizeLayer(layerName.c_str());
+    armnn::IConnectableLayer* const outputLayer = network->AddOutputLayer(0);
+
+    inputLayer->GetOutputSlot(0).Connect(dequantizeLayer->GetInputSlot(0));
+    dequantizeLayer->GetOutputSlot(0).Connect(outputLayer->GetInputSlot(0));
+
+    inputLayer->GetOutputSlot(0).SetTensorInfo(inputInfo);
+    dequantizeLayer->GetOutputSlot(0).SetTensorInfo(outputInfo);
+
+    armnn::INetworkPtr deserializedNetwork = DeserializeNetwork(SerializeNetwork(*network));
+    BOOST_CHECK(deserializedNetwork);
+
+    DequantizeLayerVerifier verifier(layerName, {inputInfo}, {outputInfo});
+    deserializedNetwork->Accept(verifier);
+}
+
 BOOST_AUTO_TEST_CASE(SerializeDeserializeDetectionPostProcess)
 {
     class DetectionPostProcessLayerVerifier : public LayerVerifierBase