Index: media/base/moving_average.h |
diff --git a/media/base/moving_average.h b/media/base/moving_average.h |
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+// Copyright 2015 The Chromium Authors. All rights reserved. |
+// Use of this source code is governed by a BSD-style license that can be |
+// found in the LICENSE file. |
+ |
+#ifndef MEDIA_BASE_MOVING_AVERAGE_H_ |
+#define MEDIA_BASE_MOVING_AVERAGE_H_ |
+ |
+#include <vector> |
+ |
+#include "base/time/time.h" |
+#include "media/base/media_export.h" |
+ |
+namespace media { |
+ |
+// Simple class for calculating a moving average of fixed size. |
+class MEDIA_EXPORT MovingAverage { |
+ public: |
+ // Creates a MovingAverage instance with space for |depth| samples. |
+ explicit MovingAverage(size_t depth); |
+ ~MovingAverage(); |
+ |
+ // Adds a new sample to the average; replaces the oldest sample if |depth_| |
+ // has been exceeded. Updates |total_| to the new sum of values. |
+ void AddSample(base::TimeDelta sample); |
+ |
+ // Returns the current average of all held samples. |
+ base::TimeDelta Average() const; |
+ |
+ // Resets the state of the class to its initial post-construction state. |
+ void Reset(); |
+ |
+ private: |
+ // Maximum number of elements allowed in the average. |
+ const size_t depth_; |
+ |
+ // Number of elements seen thus far. |
+ size_t count_; |
+ |
+ std::vector<base::TimeDelta> samples_; |
+ base::TimeDelta total_; |
+ |
+ DISALLOW_COPY_AND_ASSIGN(MovingAverage); |
+}; |
+ |
+} // namespace media |
+ |
+#endif // MEDIA_BASE_MOVING_AVERAGE_H_ |