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diff --git a/third_party/libwebrtc/modules/video_coding/timing/inter_frame_delay_variation_calculator.h b/third_party/libwebrtc/modules/video_coding/timing/inter_frame_delay_variation_calculator.h
new file mode 100644
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+++ b/third_party/libwebrtc/modules/video_coding/timing/inter_frame_delay_variation_calculator.h
@@ -0,0 +1,48 @@
+/*
+ *  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_INTER_FRAME_DELAY_VARIATION_CALCULATOR_H_
+#define MODULES_VIDEO_CODING_TIMING_INTER_FRAME_DELAY_VARIATION_CALCULATOR_H_
+
+#include <stdint.h>
+
+#include "absl/types/optional.h"
+#include "api/units/time_delta.h"
+#include "api/units/timestamp.h"
+#include "rtc_base/numerics/sequence_number_unwrapper.h"
+
+namespace webrtc {
+
+// This class calculates the inter-frame delay variation (see RFC5481) between
+// the current frame (as supplied through the current call to `Calculate`) and
+// the previous frame (as supplied through the previous call to `Calculate`).
+class InterFrameDelayVariationCalculator {
+ public:
+  InterFrameDelayVariationCalculator();
+
+  // Resets the calculator.
+  void Reset();
+
+  // Calculates the inter-frame delay variation of a frame with the given
+  // RTP timestamp. This method is called when the frame is complete.
+  absl::optional<TimeDelta> Calculate(uint32_t rtp_timestamp, Timestamp now);
+
+ private:
+  // The previous wall clock timestamp used in the calculation.
+  absl::optional<Timestamp> prev_wall_clock_;
+  // The previous RTP timestamp used in the calculation.
+  int64_t prev_rtp_timestamp_unwrapped_;
+
+  RtpTimestampUnwrapper unwrapper_;
+};
+
+}  // namespace webrtc
+
+#endif  // MODULES_VIDEO_CODING_TIMING_INTER_FRAME_DELAY_VARIATION_CALCULATOR_H_