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diff --git a/third_party/libwebrtc/modules/video_coding/utility/bandwidth_quality_scaler.h b/third_party/libwebrtc/modules/video_coding/utility/bandwidth_quality_scaler.h
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+/*
+ *  Copyright (c) 2021 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 MODULES_VIDEO_CODING_UTILITY_BANDWIDTH_QUALITY_SCALER_H_
+#define MODULES_VIDEO_CODING_UTILITY_BANDWIDTH_QUALITY_SCALER_H_
+
+#include <stddef.h>
+#include <stdint.h>
+
+#include <memory>
+#include <vector>
+
+#include "absl/types/optional.h"
+#include "api/scoped_refptr.h"
+#include "api/sequence_checker.h"
+#include "api/video_codecs/video_encoder.h"
+#include "rtc_base/experiments/encoder_info_settings.h"
+#include "rtc_base/logging.h"
+#include "rtc_base/numerics/exp_filter.h"
+#include "rtc_base/rate_statistics.h"
+#include "rtc_base/ref_count.h"
+#include "rtc_base/system/no_unique_address.h"
+#include "rtc_base/weak_ptr.h"
+
+namespace webrtc {
+
+class BandwidthQualityScalerUsageHandlerInterface {
+ public:
+  virtual ~BandwidthQualityScalerUsageHandlerInterface();
+
+  virtual void OnReportUsageBandwidthHigh() = 0;
+  virtual void OnReportUsageBandwidthLow() = 0;
+};
+
+// BandwidthQualityScaler runs asynchronously and monitors bandwidth values of
+// encoded frames. It holds a reference to a
+// BandwidthQualityScalerUsageHandlerInterface implementation to signal an
+// overuse or underuse of bandwidth (which indicate a desire to scale the video
+// stream down or up).
+class BandwidthQualityScaler {
+ public:
+  explicit BandwidthQualityScaler(
+      BandwidthQualityScalerUsageHandlerInterface* handler);
+  virtual ~BandwidthQualityScaler();
+
+  void ReportEncodeInfo(int frame_size_bytes,
+                        int64_t time_sent_in_ms,
+                        uint32_t encoded_width,
+                        uint32_t encoded_height);
+
+  // We prioritise to using the |resolution_bitrate_limits| provided by the
+  // current decoder. If not provided, we will use the default data by
+  // GetDefaultResolutionBitrateLimits().
+  void SetResolutionBitrateLimits(
+      const std::vector<VideoEncoder::ResolutionBitrateLimits>&
+          resolution_bitrate_limits);
+
+  const TimeDelta kBitrateStateUpdateInterval;
+
+ private:
+  enum class CheckBitrateResult {
+    kInsufficientSamples,
+    kNormalBitrate,
+    kHighBitRate,
+    kLowBitRate,
+  };
+
+  // We will periodically check encode bitrate, this function will make
+  // resolution up or down decisions and report the decision to the adapter.
+  void StartCheckForBitrate();
+  CheckBitrateResult CheckBitrate();
+
+  RTC_NO_UNIQUE_ADDRESS SequenceChecker task_checker_;
+  BandwidthQualityScalerUsageHandlerInterface* const handler_
+      RTC_GUARDED_BY(&task_checker_);
+
+  absl::optional<int64_t> last_time_sent_in_ms_ RTC_GUARDED_BY(&task_checker_);
+  RateStatistics encoded_bitrate_ RTC_GUARDED_BY(&task_checker_);
+  absl::optional<int> last_frame_size_pixels_ RTC_GUARDED_BY(&task_checker_);
+  rtc::WeakPtrFactory<BandwidthQualityScaler> weak_ptr_factory_;
+
+  std::vector<VideoEncoder::ResolutionBitrateLimits> resolution_bitrate_limits_;
+};
+
+}  // namespace webrtc
+#endif  // MODULES_VIDEO_CODING_UTILITY_BANDWIDTH_QUALITY_SCALER_H_