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diff --git a/compiler/luci/pass/src/helpers/SparsityFormatConverter.h b/compiler/luci/pass/src/helpers/SparsityFormatConverter.h
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+/*
+ * Copyright (c) 2022 Samsung Electronics Co., Ltd. All Rights Reserved
+ * Copyright 2020 The TensorFlow Authors. All Rights Reserved.
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ *    http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+
+#ifndef __LUCI_PASS_HELPERS_SPARSITY_FORMAT_CONVERTER_H__
+#define __LUCI_PASS_HELPERS_SPARSITY_FORMAT_CONVERTER_H__
+
+#include <cstdint>
+#include <vector>
+
+// codes under namespace sparsity referenced from
+// https://github.com/tensorflow/tensorflow/blob/3f878cff5b698b82eea85db2b60d65a2e320850e/
+//       tensorflow/lite/kernels/internal/utils/sparsity_format_converter.h
+//       tensorflow/lite/kernels/internal/utils/sparsity_format_converter.cc
+
+namespace sparsity
+{
+
+// Storage format of each dimension in a sparse tensor.
+typedef enum TfLiteDimensionType
+{
+  kTfLiteDimDense = 0,
+  kTfLiteDimSparseCSR,
+} TfLiteDimensionType;
+
+// Fixed size list of integers. Used for dimensions and inputs/outputs tensor
+// indices
+typedef struct TfLiteIntArray
+{
+  int size;
+  int data[];
+} TfLiteIntArray;
+
+// Metadata to encode each dimension in a sparse tensor.
+typedef struct TfLiteDimensionMetadata
+{
+  TfLiteDimensionType format;
+  int dense_size;
+  TfLiteIntArray *array_segments;
+  TfLiteIntArray *array_indices;
+} TfLiteDimensionMetadata;
+
+// Parameters used to encode a sparse tensor. For detailed explanation of each
+// field please refer to lite/schema/schema.fbs.
+typedef struct TfLiteSparsity
+{
+  TfLiteIntArray *traversal_order;
+  TfLiteIntArray *block_map;
+  TfLiteDimensionMetadata *dim_metadata;
+  int dim_metadata_size;
+} TfLiteSparsity;
+
+// A converter that keeps an internal representation of sparse tensor parameters
+// and converts tensors between dense and sparse formats.
+template <typename T> class FormatConverter
+{
+public:
+  /* Creates a sparse to dense converter.
+   * @param shape      Shape of the target dense tensor.
+   * @param sparsity   Sparsity parameter of the sparse TfLiteTensor.
+   */
+  FormatConverter(const std::vector<int> &shape, const TfLiteSparsity &sparsity);
+
+  const std::vector<T> &GetData() { return data_; }
+  const std::vector<std::vector<int>> &GetDimMetadata() { return dim_metadata_; }
+
+  bool SparseToDense(const T *src_data);
+
+private:
+  // Helper function for initializing this converter for sparse to dense
+  // conversion.
+  void InitSparseToDenseConverter(std::vector<int> shape, std::vector<int> traversal_order,
+                                  std::vector<TfLiteDimensionType> format,
+                                  std::vector<int> dense_size,
+                                  std::vector<std::vector<int>> segments,
+                                  std::vector<std::vector<int>> indices,
+                                  std::vector<int> block_map);
+
+  void Populate(const T *src_data, std::vector<int> indices, int level, int prev_idx,
+                int *src_data_ptr, T *dest_data);
+
+private:
+  std::vector<int> dense_shape_;
+  std::vector<int> blocked_shape_;
+  size_t dense_size_;
+  std::vector<int> traversal_order_;
+  std::vector<TfLiteDimensionType> format_;
+  std::vector<int> block_size_;
+  std::vector<int> block_map_;
+  std::vector<std::vector<int>> dim_metadata_;
+  std::vector<T> data_;
+};
+
+extern template class FormatConverter<float>;
+extern template class FormatConverter<uint16_t>;
+
+} // namespace sparsity
+
+#include <luci/IR/SparsityParam.h>
+
+namespace luci
+{
+
+sparsity::TfLiteDimensionType to_tflite_sparsity(luci::DimensionType dt);
+sparsity::TfLiteIntArray *to_tflite_sparsity(const luci::SparseIndexVector &data);
+sparsity::TfLiteSparsity to_tflite_sparsity(const luci::SparsityParam *sp);
+
+template <typename T> sparsity::TfLiteIntArray *makeTfLiteArray(const std::vector<T> &data);
+sparsity::TfLiteDimensionMetadata *
+makeTfLiteDimensionMetadata(const std::vector<luci::DimMetaData> &data);
+
+void freeTfLiteSparsity(sparsity::TfLiteSparsity &tflsp);
+
+} // namespace luci
+
+#endif // __LUCI_PASS_HELPERS_SPARSITY_FORMAT_CONVERTER_H__