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diff --git a/third_party/libwebrtc/modules/video_coding/timing/timing.h b/third_party/libwebrtc/modules/video_coding/timing/timing.h
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+/*
+ *  Copyright (c) 2011 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_TIMING_TIMING_H_
+#define MODULES_VIDEO_CODING_TIMING_TIMING_H_
+
+#include <memory>
+
+#include "absl/types/optional.h"
+#include "api/field_trials_view.h"
+#include "api/units/time_delta.h"
+#include "api/video/video_frame.h"
+#include "api/video/video_timing.h"
+#include "modules/video_coding/timing/decode_time_percentile_filter.h"
+#include "modules/video_coding/timing/timestamp_extrapolator.h"
+#include "rtc_base/experiments/field_trial_parser.h"
+#include "rtc_base/synchronization/mutex.h"
+#include "rtc_base/thread_annotations.h"
+#include "system_wrappers/include/clock.h"
+
+namespace webrtc {
+
+class VCMTiming {
+ public:
+  struct VideoDelayTimings {
+    size_t num_decoded_frames;
+    // Pre-decode delay added to smooth out frame delay variation ("jitter")
+    // caused by the network. The target delay will be no smaller than this
+    // delay, thus it is called `minimum_delay`.
+    TimeDelta minimum_delay;
+    // Estimated time needed to decode a video frame. Obtained as the 95th
+    // percentile decode time over a recent time window.
+    TimeDelta estimated_max_decode_time;
+    // Post-decode delay added to smooth out frame delay variation caused by
+    // decoding and rendering. Set to a constant.
+    TimeDelta render_delay;
+    // Minimum total delay used when determining render time for a frame.
+    // Obtained from API, `playout-delay` RTP header extension, or A/V sync.
+    TimeDelta min_playout_delay;
+    // Maximum total delay used when determining render time for a frame.
+    // Obtained from `playout-delay` RTP header extension.
+    TimeDelta max_playout_delay;
+    // Target total delay. Obtained from all the elements above.
+    TimeDelta target_delay;
+    // Current total delay. Obtained by smoothening the `target_delay`.
+    TimeDelta current_delay;
+  };
+
+  static constexpr TimeDelta kDefaultRenderDelay = TimeDelta::Millis(10);
+  static constexpr int kDelayMaxChangeMsPerS = 100;
+
+  VCMTiming(Clock* clock, const FieldTrialsView& field_trials);
+  virtual ~VCMTiming() = default;
+
+  // Resets the timing to the initial state.
+  void Reset();
+
+  // Set the amount of time needed to render an image. Defaults to 10 ms.
+  void set_render_delay(TimeDelta render_delay);
+
+  // Set the minimum time the video must be delayed on the receiver to
+  // get the desired jitter buffer level.
+  void SetJitterDelay(TimeDelta required_delay);
+
+  // Set/get the minimum playout delay from capture to render.
+  TimeDelta min_playout_delay() const;
+  void set_min_playout_delay(TimeDelta min_playout_delay);
+
+  // Set/get the maximum playout delay from capture to render in ms.
+  void set_max_playout_delay(TimeDelta max_playout_delay);
+
+  // Increases or decreases the current delay to get closer to the target delay.
+  // Calculates how long it has been since the previous call to this function,
+  // and increases/decreases the delay in proportion to the time difference.
+  void UpdateCurrentDelay(uint32_t frame_timestamp);
+
+  // Increases or decreases the current delay to get closer to the target delay.
+  // Given the actual decode time in ms and the render time in ms for a frame,
+  // this function calculates how late the frame is and increases the delay
+  // accordingly.
+  void UpdateCurrentDelay(Timestamp render_time, Timestamp actual_decode_time);
+
+  // Stops the decoder timer, should be called when the decoder returns a frame
+  // or when the decoded frame callback is called.
+  void StopDecodeTimer(TimeDelta decode_time, Timestamp now);
+
+  // Used to report that a frame is passed to decoding. Updates the timestamp
+  // filter which is used to map between timestamps and receiver system time.
+  virtual void IncomingTimestamp(uint32_t rtp_timestamp,
+                                 Timestamp last_packet_time);
+
+  // Returns the receiver system time when the frame with timestamp
+  // `frame_timestamp` should be rendered, assuming that the system time
+  // currently is `now`.
+  virtual Timestamp RenderTime(uint32_t frame_timestamp, Timestamp now) const;
+
+  // Returns the maximum time in ms that we can wait for a frame to become
+  // complete before we must pass it to the decoder. render_time==0 indicates
+  // that the frames should be processed as quickly as possible, with possibly
+  // only a small delay added to make sure that the decoder is not overloaded.
+  // In this case, the parameter too_many_frames_queued is used to signal that
+  // the decode queue is full and that the frame should be decoded as soon as
+  // possible.
+  virtual TimeDelta MaxWaitingTime(Timestamp render_time,
+                                   Timestamp now,
+                                   bool too_many_frames_queued) const;
+
+  // Returns the current target delay which is required delay + decode time +
+  // render delay.
+  TimeDelta TargetVideoDelay() const;
+
+  // Return current timing information.
+  VideoDelayTimings GetTimings() const;
+
+  void SetTimingFrameInfo(const TimingFrameInfo& info);
+  absl::optional<TimingFrameInfo> GetTimingFrameInfo();
+
+  void SetMaxCompositionDelayInFrames(
+      absl::optional<int> max_composition_delay_in_frames);
+
+  VideoFrame::RenderParameters RenderParameters() const;
+
+  // Updates the last time a frame was scheduled for decoding.
+  void SetLastDecodeScheduledTimestamp(Timestamp last_decode_scheduled);
+
+ private:
+  TimeDelta EstimatedMaxDecodeTime() const RTC_EXCLUSIVE_LOCKS_REQUIRED(mutex_);
+  Timestamp RenderTimeInternal(uint32_t frame_timestamp, Timestamp now) const
+      RTC_EXCLUSIVE_LOCKS_REQUIRED(mutex_);
+  TimeDelta TargetDelayInternal() const RTC_EXCLUSIVE_LOCKS_REQUIRED(mutex_);
+  TimeDelta StatsTargetDelayInternal() const
+      RTC_EXCLUSIVE_LOCKS_REQUIRED(mutex_);
+  bool UseLowLatencyRendering() const RTC_EXCLUSIVE_LOCKS_REQUIRED(mutex_);
+
+  mutable Mutex mutex_;
+  Clock* const clock_;
+  const std::unique_ptr<TimestampExtrapolator> ts_extrapolator_
+      RTC_PT_GUARDED_BY(mutex_);
+  std::unique_ptr<DecodeTimePercentileFilter> decode_time_filter_
+      RTC_GUARDED_BY(mutex_) RTC_PT_GUARDED_BY(mutex_);
+  TimeDelta render_delay_ RTC_GUARDED_BY(mutex_);
+  // Best-effort playout delay range for frames from capture to render.
+  // The receiver tries to keep the delay between `min_playout_delay_ms_`
+  // and `max_playout_delay_ms_` taking the network jitter into account.
+  // A special case is where min_playout_delay_ms_ = max_playout_delay_ms_ = 0,
+  // in which case the receiver tries to play the frames as they arrive.
+  TimeDelta min_playout_delay_ RTC_GUARDED_BY(mutex_);
+  TimeDelta max_playout_delay_ RTC_GUARDED_BY(mutex_);
+  TimeDelta jitter_delay_ RTC_GUARDED_BY(mutex_);
+  TimeDelta current_delay_ RTC_GUARDED_BY(mutex_);
+  uint32_t prev_frame_timestamp_ RTC_GUARDED_BY(mutex_);
+  absl::optional<TimingFrameInfo> timing_frame_info_ RTC_GUARDED_BY(mutex_);
+  size_t num_decoded_frames_ RTC_GUARDED_BY(mutex_);
+  absl::optional<int> max_composition_delay_in_frames_ RTC_GUARDED_BY(mutex_);
+  // Set by the field trial WebRTC-ZeroPlayoutDelay. The parameter min_pacing
+  // determines the minimum delay between frames scheduled for decoding that is
+  // used when min playout delay=0 and max playout delay>=0.
+  FieldTrialParameter<TimeDelta> zero_playout_delay_min_pacing_
+      RTC_GUARDED_BY(mutex_);
+  // Timestamp at which the last frame was scheduled to be sent to the decoder.
+  // Used only when the RTP header extension playout delay is set to min=0 ms
+  // which is indicated by a render time set to 0.
+  Timestamp last_decode_scheduled_ RTC_GUARDED_BY(mutex_);
+};
+}  // namespace webrtc
+
+#endif  // MODULES_VIDEO_CODING_TIMING_TIMING_H_