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diff --git a/media/webrtc/trunk/webrtc/modules/video_coding/utility/include/frame_dropper.h b/media/webrtc/trunk/webrtc/modules/video_coding/utility/include/frame_dropper.h
new file mode 100644
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+++ b/media/webrtc/trunk/webrtc/modules/video_coding/utility/include/frame_dropper.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 WEBRTC_MODULES_VIDEO_CODING_UTILITY_INCLUDE_FRAME_DROPPER_H_
+#define WEBRTC_MODULES_VIDEO_CODING_UTILITY_INCLUDE_FRAME_DROPPER_H_
+
+#include <cstddef>
+
+#include "webrtc/base/exp_filter.h"
+#include "webrtc/typedefs.h"
+
+namespace webrtc
+{
+
+// The Frame Dropper implements a variant of the leaky bucket algorithm
+// for keeping track of when to drop frames to avoid bit rate
+// over use when the encoder can't keep its bit rate.
+class FrameDropper
+{
+public:
+    FrameDropper();
+    explicit FrameDropper(float max_time_drops);
+    virtual ~FrameDropper() {}
+
+    // Resets the FrameDropper to its initial state.
+    // This means that the frameRateWeight is set to its
+    // default value as well.
+    virtual void Reset();
+
+    virtual void Enable(bool enable);
+    // Answers the question if it's time to drop a frame
+    // if we want to reach a given frame rate. Must be
+    // called for every frame.
+    //
+    // Return value     : True if we should drop the current frame
+    virtual bool DropFrame();
+    // Updates the FrameDropper with the size of the latest encoded
+    // frame. The FrameDropper calculates a new drop ratio (can be
+    // seen as the probability to drop a frame) and updates its
+    // internal statistics.
+    //
+    // Input:
+    //          - frameSizeBytes    : The size of the latest frame
+    //                                returned from the encoder.
+    //          - deltaFrame        : True if the encoder returned
+    //                                a key frame.
+    virtual void Fill(size_t frameSizeBytes, bool deltaFrame);
+
+    virtual void Leak(uint32_t inputFrameRate);
+
+    void UpdateNack(uint32_t nackBytes);
+
+    // Sets the target bit rate and the frame rate produced by
+    // the camera.
+    //
+    // Input:
+    //          - bitRate       : The target bit rate
+    virtual void SetRates(float bitRate, float incoming_frame_rate);
+
+    // Return value     : The current average frame rate produced
+    //                    if the DropFrame() function is used as
+    //                    instruction of when to drop frames.
+    virtual float ActualFrameRate(uint32_t inputFrameRate) const;
+
+private:
+    void FillBucket(float inKbits, float outKbits);
+    void UpdateRatio();
+    void CapAccumulator();
+
+    rtc::ExpFilter _keyFrameSizeAvgKbits;
+    rtc::ExpFilter _keyFrameRatio;
+    float _keyFrameSpreadFrames;
+    int32_t _keyFrameCount;
+    float _accumulator;
+    float _accumulatorMax;
+    float _targetBitRate;
+    bool _dropNext;
+    rtc::ExpFilter _dropRatio;
+    int32_t _dropCount;
+    float _windowSize;
+    float _incoming_frame_rate;
+    bool _wasBelowMax;
+    bool _enabled;
+    bool _fastMode;
+    float _cap_buffer_size;
+    float _max_time_drops;
+}; // end of VCMFrameDropper class
+
+}  // namespace webrtc
+
+#endif // WEBRTC_MODULES_VIDEO_CODING_UTILITY_INCLUDE_FRAME_DROPPER_H_