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+// Copyright 2016 The Draco Authors.
+//
+// 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.
+//
+// A set of classes for quantizing and dequantizing of floating point values
+// into integers.
+// The quantization works on all floating point numbers within (-range, +range)
+// interval producing integers in range
+// (-max_quantized_value, +max_quantized_value).
+
+#ifndef DRACO_CORE_QUANTIZATION_UTILS_H_
+#define DRACO_CORE_QUANTIZATION_UTILS_H_
+
+#include <stdint.h>
+
+#include <cmath>
+
+#include "draco/core/macros.h"
+
+namespace draco {
+
+// Class for quantizing single precision floating point values. The values
+// should be centered around zero and be within interval (-range, +range), where
+// the range is specified in the Init() method. Alternatively, the quantization
+// can be defined by |delta| that specifies the distance between two quantized
+// values. Note that the quantizer always snaps the values to the nearest
+// integer value. E.g. for |delta| == 1.f, values -0.4f and 0.4f would be
+// both quantized to 0 while value 0.6f would be quantized to 1. If a value
+// lies exactly between two quantized states, it is always rounded up. E.g.,
+// for |delta| == 1.f, value -0.5f would be quantized to 0 while 0.5f would be
+// quantized to 1.
+class Quantizer {
+ public:
+  Quantizer();
+  void Init(float range, int32_t max_quantized_value);
+  void Init(float delta);
+  inline int32_t QuantizeFloat(float val) const {
+    val *= inverse_delta_;
+    return static_cast<int32_t>(floor(val + 0.5f));
+  }
+  inline int32_t operator()(float val) const { return QuantizeFloat(val); }
+
+ private:
+  float inverse_delta_;
+};
+
+// Class for dequantizing values that were previously quantized using the
+// Quantizer class.
+class Dequantizer {
+ public:
+  Dequantizer();
+
+  // Initializes the dequantizer. Both parameters must correspond to the values
+  // provided to the initializer of the Quantizer class.
+  // Returns false when the initialization fails.
+  bool Init(float range, int32_t max_quantized_value);
+
+  // Initializes the dequantizer using the |delta| between two quantized values.
+  bool Init(float delta);
+
+  inline float DequantizeFloat(int32_t val) const {
+    return static_cast<float>(val) * delta_;
+  }
+  inline float operator()(int32_t val) const { return DequantizeFloat(val); }
+
+ private:
+  float delta_;
+};
+
+}  // namespace draco
+
+#endif  // DRACO_CORE_QUANTIZATION_UTILS_H_