[MedFilter] implemented median filter with generics over window size

src/shared/algorithms/Filters/MedFilter.h

+/* Copyright (c) 2023 Skyward Experimental Rocketry
+ * Author: Federico Lolli
+ *
+ * Permission is hereby granted, free of charge, to any person obtaining a copy
+ * of this software and associated documentation files (the "Software"), to deal
+ * in the Software without restriction, including without limitation the rights
+ * to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
+ * copies of the Software, and to permit persons to whom the Software is
+ * furnished to do so, subject to the following conditions:
+ *
+ * The above copyright notice and this permission notice shall be included in
+ * all copies or substantial portions of the Software.
+ *
+ * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
+ * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
+ * FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
+ * AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
+ * LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
+ * OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN
+ * THE SOFTWARE.
+ */
+
+#pragma once
+
+#include <array>
+
+namespace Boardcore
+{
+
+/**
+ * @brief Implementation of a Median Filter
+ *
+ * @tparam windowSize The size of the window
+ * @note WARNING: should be noted that the first windowSize - 1 outputs will be
+ * wrong because the window is not full yet (consider using a Shadow Mode)
+ */
+template <size_t windowSize>
+class MedFilter
+{
+    // windowSize must be odd
+    static_assert(windowSize % 2 == 1, "windowSize must be odd");
+
+public:
+    /**
+     * @brief Construct a new Median Filter object
+     *
+     * @note WARNING: Initialize output at 0 at first
+     */
+    explicit MedFilter() : window({}) {}
+
+    /**
+     * @brief Filter the input
+     *
+     * @param input The input to filter
+     * @note WARNING: should be noted that the first windowSize - 1 outputs will
+     * be wrong because the window is not full yet (consider using a Shadow
+     * Mode)
+     */
+    float filter(float input)
+    {
+        slideWindow(input);
+        return median();
+    }
+
+private:
+    /**
+     * @brief Slide the window by one position to the left and add the new input
+     * to the right
+     *
+     * @param input The input to add to the window
+     */
+    void slideWindow(float input)
+    {
+        for (size_t i = 0; i < windowSize - 1; i++)
+        {
+            window[i] = window[i + 1];
+        }
+        window[windowSize - 1] = input;
+    }
+
+    /**
+     * @brief Calculate the median of the window
+     */
+    float median()
+    {
+        std::array<float, windowSize> sortedWindow = window;
+        std::sort(sortedWindow.begin(), sortedWindow.end());
+        return sortedWindow[windowSize / 2];
+    }
+
+    std::array<float, windowSize> window;
+};
+
+}  // namespace Boardcore