utils: tuning: libtuning: Implement math helpers

Implement math helpers for libtuning. This includes:
- Average, a wrapper class for numpy averaging functions
- Gradient, a class that represents gradients, for distributing and
  mapping
- Smoothing, a wrapper class for cv2 smoothing functions

Signed-off-by: Paul Elder <paul.elder@ideasonboard.com>
Reviewed-by: Laurent Pinchart <laurent.pinchart@ideasonboard.com>

utils/tuning/libtuning/average.py

@@ -0,0 +1,21 @@
+# SPDX-License-Identifier: GPL-2.0-or-later
+#
+# Copyright (C) 2022, Paul Elder <paul.elder@ideasonboard.com>
+#
+# average.py - Wrapper for numpy averaging functions to enable duck-typing
+
+import numpy as np
+
+
+# @brief Wrapper for np averaging functions so that they can be duck-typed
+class Average(object):
+    def __init__(self):
+        pass
+
+    def average(self, np_array):
+        raise NotImplementedError
+
+
+class Mean(Average):
+    def average(self, np_array):
+        return np.mean(np_array)