modules/video_coding refactorings

webrtc/modules/video_coding/main/source/rtt_filter.cc

Index: webrtc/modules/video_coding/main/source/rtt_filter.cc
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 5742e8fa89cc8e44230ccc0be3746e7cef971631..0000000000000000000000000000000000000000
--- 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);
-}
-
-}