--- /dev/null	Thu Jan 01 00:00:00 1970 +0000
+++ b/trajectorymanagement/src/DTWMetric.h	Mon Feb 22 22:09:35 2021 -0500
@@ -0,0 +1,115 @@
+#ifndef DTWMETRIC_H_
+#define DTWMETRIC_H_
+
+#include "Metric.h"
+
+/**
+ * DTWMetric class.
+ *
+ * The Dynamic Time Warping metric measures the similarity between two trajectories.
+ */
+template<typename Tr, typename To>
+class DTWMetric: public Metric<Tr, To>
+{
+public:
+	/**
+	 * Constructor.
+	 */
+	DTWMetric()
+	{
+		maxDTWValue = (std::numeric_limits<To>::max()) / To(2);
+	}
+
+	/**
+	 * Set maximum value that occurs during the calculation process.
+	 *
+	 * @param[in] maxDTWValue maximum value
+	 */
+	bool setMaxDTWValue(To maxDTWValue)
+	{
+		if (maxDTWValue >= 0.0)
+		{
+			this->maxDTWValue = maxDTWValue;
+			return true;
+		}
+		return false;
+	}
+
+	/**
+	 * Set maximum value that occurs during the calculation process.
+	 *
+	 * @param[in] imgSize image size
+	 * @param[in] eps machine epsilon
+	 */
+	bool setMaxDTWValue(CvSize &imgSize, double eps)
+	{
+		if (imgSize.width > 0 && imgSize.height > 0 && eps > 0)
+		{
+			cv::Point_<int> p(imgSize.width, imgSize.height);
+			maxDTWValue = std::numeric_limits<To>::max() - norm(p) - eps;
+			return true;
+		}
+		return false;
+	}
+
+	/**
+	 * Compute similarity between two trajectories.
+	 *
+	 * @param[in] a input trajectory
+	 * @param[in] b input trajectory
+	 * @param[out] result distance between two trajectories.
+	 */
+	void distance(const Trajectory<Tr> *a, const Trajectory<Tr> *b, To &result, unsigned int nbOfPoints = std::numeric_limits<unsigned int>::max()) 
+	{
+		To DTW[a->size() + 1][b->size() + 1];
+
+		{ //initialization
+			for (unsigned int i = 0; i <= a->size(); ++i)
+			{
+				DTW[i][0] = maxDTWValue;
+			}
+
+			for (unsigned int j = 0; j <= b->size(); ++j)
+			{
+				DTW[0][j] = maxDTWValue;
+			}
+
+			DTW[0][0] = 0.0;
+		}
+
+		{ //algorithm
+			for (unsigned int i = 1; i <= a->size(); ++i)
+			{
+				for (unsigned int j = 1; j <= b->size(); ++j)
+				{
+					To smallest = min(DTW[i - 1][j], DTW[i][j - 1], DTW[i - 1][j - 1]);
+					cv::Point3_<typeof(static_cast<Tr>(a->getPoint(i-1)).x)> p(a->getPoint(i - 1) - b->getPoint(j - 1));
+					To distance = std::sqrt(std::pow(p.x, 2) + std::pow(p.y, 2) + std::pow(p.z, 2));
+					DTW[i][j] = std::min(smallest + distance, maxDTWValue);
+				}
+			}
+		}
+
+		result = DTW[a->size()][b->size()];
+	}
+
+private:
+	/**
+	 * Maximum value that occurs during the calculation process.
+	 */
+	To maxDTWValue;
+
+	/**
+	 * Compute the minimum of \a a, \a b and \c c.
+	 *
+	 * @param[in] a input parameter
+	 * @param[in] b input parameter
+	 * @param[in] c input parameter
+	 */
+	To min(To a, To b, To c)
+	{
+		return std::min(std::min(a, b), c);
+	}
+};
+
+#endif /* DTWMETRIC_H_ */