Repo created

TMessagesProj/jni/voip/webrtc/rtc_base/bitrate_tracker.h

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+/*
+ *  Copyright (c) 2023 The WebRTC project authors. All Rights Reserved.
+ *
+ *  Use of this source code is governed by a BSD-style license
+ *  that can be found in the LICENSE file in the root of the source
+ *  tree. An additional intellectual property rights grant can be found
+ *  in the file PATENTS.  All contributing project authors may
+ *  be found in the AUTHORS file in the root of the source tree.
+ */
+
+#ifndef RTC_BASE_BITRATE_TRACKER_H_
+#define RTC_BASE_BITRATE_TRACKER_H_
+
+#include <stddef.h>
+#include <stdint.h>
+
+#include "absl/types/optional.h"
+#include "api/units/data_rate.h"
+#include "api/units/data_size.h"
+#include "api/units/time_delta.h"
+#include "api/units/timestamp.h"
+#include "rtc_base/rate_statistics.h"
+#include "rtc_base/system/rtc_export.h"
+
+namespace webrtc {
+// Class to estimate bitrates over running window.
+// Timestamps used in Update(), Rate() and SetWindowSize() must never
+// decrease for two consecutive calls.
+// This class is thread unsafe.
+class RTC_EXPORT BitrateTracker {
+ public:
+  // max_window_sizes = Maximum window size for the rate estimation.
+  //                    Initial window size is set to this, but may be changed
+  //                    to something lower by calling SetWindowSize().
+  explicit BitrateTracker(TimeDelta max_window_size);
+
+  BitrateTracker(const BitrateTracker&) = default;
+  BitrateTracker(BitrateTracker&&) = default;
+  BitrateTracker& operator=(const BitrateTracker&) = delete;
+  BitrateTracker& operator=(BitrateTracker&&) = delete;
+
+  ~BitrateTracker() = default;
+
+  // Resets instance to original state.
+  void Reset() { impl_.Reset(); }
+
+  // Updates bitrate with a new data point, moving averaging window as needed.
+  void Update(int64_t bytes, Timestamp now);
+  void Update(DataSize size, Timestamp now) { Update(size.bytes(), now); }
+
+  // Returns bitrate, moving averaging window as needed.
+  // Returns nullopt when bitrate can't be measured.
+  absl::optional<DataRate> Rate(Timestamp now) const;
+
+  // Update the size of the averaging window. The maximum allowed value for
+  // `window_size` is `max_window_size` as supplied in the constructor.
+  bool SetWindowSize(TimeDelta window_size, Timestamp now);
+
+ private:
+  RateStatistics impl_;
+};
+}  // namespace webrtc
+
+#endif  // RTC_BASE_BITRATE_TRACKER_H_