webrtc/modules/video_coding/main/source/inter_frame_delay.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_INTER_FRAME_DELAY_H_
#define WEBRTC_MODULES_VIDEO_CODING_INTER_FRAME_DELAY_H_
#include "typedefs.h"
namespace webrtc
{
class VCMInterFrameDelay
{
public:
VCMInterFrameDelay();
// Resets the estimate. Zeros are given as parameters.
void Reset();
// Calculates the delay of a frame with the given timestamp.
// This method is called when the frame is complete.
//
// Input:
// - timestamp : RTP timestamp of a received frame
// - *delay : Pointer to memory where the result should be stored
// - currentWallClock : The current time in milliseconds.
// Should be -1 for normal operation, only used for testing.
// Return value : true if OK, false when reordered timestamps
bool CalculateDelay(WebRtc_UWord32 timestamp,
WebRtc_Word64 *delay,
WebRtc_Word64 currentWallClock = -1);
// Returns the current difference between incoming timestamps
//
// Return value : Wrap-around compensated difference between incoming
// timestamps.
WebRtc_UWord32 CurrentTimeStampDiffMs() const;
private:
// Controls if the RTP timestamp counter has had a wrap around
// between the current and the previously received frame.
//
// Input:
// - timestmap : RTP timestamp of the current frame.
void CheckForWrapArounds(WebRtc_UWord32 timestamp);
WebRtc_Word64 _zeroWallClock; // Local timestamp of the first video packet received
WebRtc_Word32 _wrapArounds; // Number of wrapArounds detected
// The previous timestamp passed to the delay estimate
WebRtc_UWord32 _prevTimestamp;
// The previous wall clock timestamp used by the delay estimate
WebRtc_Word64 _prevWallClock;
// Wrap-around compensated difference between incoming timestamps
WebRtc_Word64 _dTS;
};
} // namespace webrtc
#endif // WEBRTC_MODULES_VIDEO_CODING_INTER_FRAME_DELAY_H_