diff options
Diffstat (limited to 'webrtc/modules/video_coding/main/source/rtt_filter.cc')
| -rw-r--r-- | webrtc/modules/video_coding/main/source/rtt_filter.cc | 202 |
1 files changed, 0 insertions, 202 deletions
diff --git a/webrtc/modules/video_coding/main/source/rtt_filter.cc b/webrtc/modules/video_coding/main/source/rtt_filter.cc deleted file mode 100644 index 5742e8fa89..0000000000 --- a/webrtc/modules/video_coding/main/source/rtt_filter.cc +++ /dev/null @@ -1,202 +0,0 @@ -/* - * 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. - */ - -#include "webrtc/modules/video_coding/main/source/internal_defines.h" -#include "webrtc/modules/video_coding/main/source/rtt_filter.h" - -#include <math.h> -#include <stdlib.h> -#include <string.h> - -namespace webrtc { - -VCMRttFilter::VCMRttFilter() - : _filtFactMax(35), - _jumpStdDevs(2.5), - _driftStdDevs(3.5), - _detectThreshold(kMaxDriftJumpCount) { - Reset(); -} - -VCMRttFilter& -VCMRttFilter::operator=(const VCMRttFilter& rhs) -{ - if (this != &rhs) - { - _gotNonZeroUpdate = rhs._gotNonZeroUpdate; - _avgRtt = rhs._avgRtt; - _varRtt = rhs._varRtt; - _maxRtt = rhs._maxRtt; - _filtFactCount = rhs._filtFactCount; - _jumpCount = rhs._jumpCount; - _driftCount = rhs._driftCount; - memcpy(_jumpBuf, rhs._jumpBuf, sizeof(_jumpBuf)); - memcpy(_driftBuf, rhs._driftBuf, sizeof(_driftBuf)); - } - return *this; -} - -void -VCMRttFilter::Reset() -{ - _gotNonZeroUpdate = false; - _avgRtt = 0; - _varRtt = 0; - _maxRtt = 0; - _filtFactCount = 1; - _jumpCount = 0; - _driftCount = 0; - memset(_jumpBuf, 0, kMaxDriftJumpCount); - memset(_driftBuf, 0, kMaxDriftJumpCount); -} - -void -VCMRttFilter::Update(int64_t rttMs) -{ - if (!_gotNonZeroUpdate) - { - if (rttMs == 0) - { - return; - } - _gotNonZeroUpdate = true; - } - - // Sanity check - if (rttMs > 3000) - { - rttMs = 3000; - } - - double filtFactor = 0; - if (_filtFactCount > 1) - { - filtFactor = static_cast<double>(_filtFactCount - 1) / _filtFactCount; - } - _filtFactCount++; - if (_filtFactCount > _filtFactMax) - { - // This prevents filtFactor from going above - // (_filtFactMax - 1) / _filtFactMax, - // e.g., _filtFactMax = 50 => filtFactor = 49/50 = 0.98 - _filtFactCount = _filtFactMax; - } - double oldAvg = _avgRtt; - double oldVar = _varRtt; - _avgRtt = filtFactor * _avgRtt + (1 - filtFactor) * rttMs; - _varRtt = filtFactor * _varRtt + (1 - filtFactor) * - (rttMs - _avgRtt) * (rttMs - _avgRtt); - _maxRtt = VCM_MAX(rttMs, _maxRtt); - if (!JumpDetection(rttMs) || !DriftDetection(rttMs)) - { - // In some cases we don't want to update the statistics - _avgRtt = oldAvg; - _varRtt = oldVar; - } -} - -bool -VCMRttFilter::JumpDetection(int64_t rttMs) -{ - double diffFromAvg = _avgRtt - rttMs; - if (fabs(diffFromAvg) > _jumpStdDevs * sqrt(_varRtt)) - { - int diffSign = (diffFromAvg >= 0) ? 1 : -1; - int jumpCountSign = (_jumpCount >= 0) ? 1 : -1; - if (diffSign != jumpCountSign) - { - // Since the signs differ the samples currently - // in the buffer is useless as they represent a - // jump in a different direction. - _jumpCount = 0; - } - if (abs(_jumpCount) < kMaxDriftJumpCount) - { - // Update the buffer used for the short time - // statistics. - // The sign of the diff is used for updating the counter since - // we want to use the same buffer for keeping track of when - // the RTT jumps down and up. - _jumpBuf[abs(_jumpCount)] = rttMs; - _jumpCount += diffSign; - } - if (abs(_jumpCount) >= _detectThreshold) - { - // Detected an RTT jump - ShortRttFilter(_jumpBuf, abs(_jumpCount)); - _filtFactCount = _detectThreshold + 1; - _jumpCount = 0; - } - else - { - return false; - } - } - else - { - _jumpCount = 0; - } - return true; -} - -bool -VCMRttFilter::DriftDetection(int64_t rttMs) -{ - if (_maxRtt - _avgRtt > _driftStdDevs * sqrt(_varRtt)) - { - if (_driftCount < kMaxDriftJumpCount) - { - // Update the buffer used for the short time - // statistics. - _driftBuf[_driftCount] = rttMs; - _driftCount++; - } - if (_driftCount >= _detectThreshold) - { - // Detected an RTT drift - ShortRttFilter(_driftBuf, _driftCount); - _filtFactCount = _detectThreshold + 1; - _driftCount = 0; - } - } - else - { - _driftCount = 0; - } - return true; -} - -void -VCMRttFilter::ShortRttFilter(int64_t* buf, uint32_t length) -{ - if (length == 0) - { - return; - } - _maxRtt = 0; - _avgRtt = 0; - for (uint32_t i=0; i < length; i++) - { - if (buf[i] > _maxRtt) - { - _maxRtt = buf[i]; - } - _avgRtt += buf[i]; - } - _avgRtt = _avgRtt / static_cast<double>(length); -} - -int64_t -VCMRttFilter::RttMs() const -{ - return static_cast<int64_t>(_maxRtt + 0.5); -} - -} |