| /* |
| * 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_RTT_FILTER_H_ |
| #define WEBRTC_MODULES_VIDEO_CODING_RTT_FILTER_H_ |
| |
| #include "typedefs.h" |
| |
| namespace webrtc |
| { |
| |
| class VCMRttFilter |
| { |
| public: |
| VCMRttFilter(WebRtc_Word32 vcmId = 0, WebRtc_Word32 receiverId = 0); |
| |
| VCMRttFilter& operator=(const VCMRttFilter& rhs); |
| |
| // Resets the filter. |
| void Reset(); |
| // Updates the filter with a new sample. |
| void Update(WebRtc_UWord32 rttMs); |
| // A getter function for the current RTT level in ms. |
| WebRtc_UWord32 RttMs() const; |
| |
| private: |
| // The size of the drift and jump memory buffers |
| // and thus also the detection threshold for these |
| // detectors in number of samples. |
| enum { kMaxDriftJumpCount = 5 }; |
| // Detects RTT jumps by comparing the difference between |
| // samples and average to the standard deviation. |
| // Returns true if the long time statistics should be updated |
| // and false otherwise |
| bool JumpDetection(WebRtc_UWord32 rttMs); |
| // Detects RTT drifts by comparing the difference between |
| // max and average to the standard deviation. |
| // Returns true if the long time statistics should be updated |
| // and false otherwise |
| bool DriftDetection(WebRtc_UWord32 rttMs); |
| // Computes the short time average and maximum of the vector buf. |
| void ShortRttFilter(WebRtc_UWord32* buf, WebRtc_UWord32 length); |
| |
| WebRtc_Word32 _vcmId; |
| WebRtc_Word32 _receiverId; |
| bool _gotNonZeroUpdate; |
| double _avgRtt; |
| double _varRtt; |
| WebRtc_UWord32 _maxRtt; |
| WebRtc_UWord32 _filtFactCount; |
| const WebRtc_UWord32 _filtFactMax; |
| const double _jumpStdDevs; |
| const double _driftStdDevs; |
| WebRtc_Word32 _jumpCount; |
| WebRtc_Word32 _driftCount; |
| const WebRtc_Word32 _detectThreshold; |
| WebRtc_UWord32 _jumpBuf[kMaxDriftJumpCount]; |
| WebRtc_UWord32 _driftBuf[kMaxDriftJumpCount]; |
| }; |
| |
| } // namespace webrtc |
| |
| #endif // WEBRTC_MODULES_VIDEO_CODING_RTT_FILTER_H_ |