IVGCVSW-3260 Add serialization support for SpaceToDepth

Signed-off-by: Aron Virginas-Tar <Aron.Virginas-Tar@arm.com>
Change-Id: Ie0d9561437ff5da8fa4db81fee1e70bd18c47034
diff --git a/src/armnnSerializer/ArmnnSchema.fbs b/src/armnnSerializer/ArmnnSchema.fbs
index 5a001de..1204ad8 100644
--- a/src/armnnSerializer/ArmnnSchema.fbs
+++ b/src/armnnSerializer/ArmnnSchema.fbs
@@ -121,7 +121,8 @@
     Dequantize = 36,
     Merge = 37,
     Switch = 38,
-    Concat = 39
+    Concat = 39,
+    SpaceToDepth = 40
 }
 
 // Base layer table to be used as part of other layers
@@ -338,6 +339,16 @@
     dataLayout:DataLayout;
 }
 
+table SpaceToDepthLayer {
+    base:LayerBase;
+    descriptor:SpaceToDepthDescriptor;
+}
+
+table SpaceToDepthDescriptor {
+    blockSize:uint;
+    dataLayout:DataLayout;
+}
+
 table SubtractionLayer {
     base:LayerBase;
 }
@@ -584,7 +595,8 @@
     DequantizeLayer,
     MergeLayer,
     SwitchLayer,
-    ConcatLayer
+    ConcatLayer,
+    SpaceToDepthLayer
 }
 
 table AnyLayer {
diff --git a/src/armnnSerializer/Serializer.cpp b/src/armnnSerializer/Serializer.cpp
index 676d10c..131bb95 100644
--- a/src/armnnSerializer/Serializer.cpp
+++ b/src/armnnSerializer/Serializer.cpp
@@ -788,7 +788,17 @@
                                                const armnn::SpaceToDepthDescriptor& spaceToDepthDescriptor,
                                                const char* name)
 {
-    throw armnn::Exception("SerializerVisitor::VisitSpaceToDepthLayer is not yet implemented");
+    auto flatBufferBaseLayer  = CreateLayerBase(layer, serializer::LayerType::LayerType_SpaceToDepth);
+    auto flatBufferDescriptor =
+        CreateSpaceToDepthDescriptor(m_flatBufferBuilder,
+                                     spaceToDepthDescriptor.m_BlockSize,
+                                     GetFlatBufferDataLayout(spaceToDepthDescriptor.m_DataLayout));
+
+    auto flatBufferLayer = serializer::CreateSpaceToDepthLayer(m_flatBufferBuilder,
+                                                               flatBufferBaseLayer,
+                                                               flatBufferDescriptor);
+
+    CreateAnyLayer(flatBufferLayer.o, serializer::Layer::Layer_SpaceToDepthLayer);
 }
 
 // Build FlatBuffer for Splitter Layer
diff --git a/src/armnnSerializer/SerializerSupport.md b/src/armnnSerializer/SerializerSupport.md
index 734ae18..865cdf0 100644
--- a/src/armnnSerializer/SerializerSupport.md
+++ b/src/armnnSerializer/SerializerSupport.md
@@ -39,6 +39,7 @@
 * Rsqrt
 * Softmax
 * SpaceToBatchNd
+* SpaceToDepth
 * Splitter
 * StridedSlice
 * Subtraction
diff --git a/src/armnnSerializer/test/SerializerTests.cpp b/src/armnnSerializer/test/SerializerTests.cpp
index 752cf0c..a757e16 100644
--- a/src/armnnSerializer/test/SerializerTests.cpp
+++ b/src/armnnSerializer/test/SerializerTests.cpp
@@ -2045,6 +2045,63 @@
     deserializedNetwork->Accept(verifier);
 }
 
+BOOST_AUTO_TEST_CASE(SerializeSpaceToDepth)
+{
+    class SpaceToDepthLayerVerifier : public LayerVerifierBase
+    {
+    public:
+        SpaceToDepthLayerVerifier(const std::string& layerName,
+                                  const std::vector<armnn::TensorInfo>& inputInfos,
+                                  const std::vector<armnn::TensorInfo>& outputInfos,
+                                  const armnn::SpaceToDepthDescriptor& descriptor)
+            : LayerVerifierBase(layerName, inputInfos, outputInfos)
+            , m_Descriptor(descriptor) {}
+
+        void VisitSpaceToDepthLayer(const armnn::IConnectableLayer* layer,
+                                    const armnn::SpaceToDepthDescriptor& descriptor,
+                                    const char* name) override
+        {
+            VerifyNameAndConnections(layer, name);
+            VerifyDescriptor(descriptor);
+        }
+
+    private:
+        void VerifyDescriptor(const armnn::SpaceToDepthDescriptor& descriptor)
+        {
+            BOOST_TEST(descriptor.m_BlockSize == m_Descriptor.m_BlockSize);
+            BOOST_TEST(GetDataLayoutName(descriptor.m_DataLayout) == GetDataLayoutName(m_Descriptor.m_DataLayout));
+        }
+
+        armnn::SpaceToDepthDescriptor m_Descriptor;
+    };
+
+    const std::string layerName("spaceToDepth");
+
+    const armnn::TensorInfo inputInfo ({ 1, 16, 8,  3 }, armnn::DataType::Float32);
+    const armnn::TensorInfo outputInfo({ 1,  8, 4, 12 }, armnn::DataType::Float32);
+
+    armnn::SpaceToDepthDescriptor desc;
+    desc.m_BlockSize  = 2;
+    desc.m_DataLayout = armnn::DataLayout::NHWC;
+
+    armnn::INetworkPtr network = armnn::INetwork::Create();
+    armnn::IConnectableLayer* const inputLayer        = network->AddInputLayer(0);
+    armnn::IConnectableLayer* const spaceToDepthLayer = network->AddSpaceToDepthLayer(desc, layerName.c_str());
+    armnn::IConnectableLayer* const outputLayer       = network->AddOutputLayer(0);
+
+    inputLayer->GetOutputSlot(0).Connect(spaceToDepthLayer->GetInputSlot(0));
+    spaceToDepthLayer->GetOutputSlot(0).Connect(outputLayer->GetInputSlot(0));
+
+    inputLayer->GetOutputSlot(0).SetTensorInfo(inputInfo);
+    spaceToDepthLayer->GetOutputSlot(0).SetTensorInfo(outputInfo);
+
+    armnn::INetworkPtr deserializedNetwork = DeserializeNetwork(SerializeNetwork(*network));
+    BOOST_CHECK(deserializedNetwork);
+
+    SpaceToDepthLayerVerifier verifier(layerName, {inputInfo}, {outputInfo}, desc);
+    deserializedNetwork->Accept(verifier);
+}
+
 BOOST_AUTO_TEST_CASE(SerializeSplitter)
 {
     class SplitterLayerVerifier : public LayerVerifierBase