Move timestamp_extrapolator and rtp_to_ntp to system wrapper so that it can be shared by both audio and video engine.

BUG=3111
TEST=try bots
R=mflodman@webrtc.org

Review URL: https://webrtc-codereview.appspot.com/13459004

git-svn-id: http://webrtc.googlecode.com/svn/trunk@6074 4adac7df-926f-26a2-2b94-8c16560cd09d
diff --git a/webrtc/modules/video_coding/main/source/Android.mk b/webrtc/modules/video_coding/main/source/Android.mk
index 9ebdbed..a8cf2d0 100644
--- a/webrtc/modules/video_coding/main/source/Android.mk
+++ b/webrtc/modules/video_coding/main/source/Android.mk
@@ -37,7 +37,6 @@
     receiver.cc \
     rtt_filter.cc \
     session_info.cc \
-    timestamp_extrapolator.cc \
     timestamp_map.cc \
     timing.cc \
     video_coding_impl.cc
@@ -56,7 +55,7 @@
     $(LOCAL_PATH)/../../../../common_video/vplib/main/interface \
     $(LOCAL_PATH)/../../../../common_video/interface \
     $(LOCAL_PATH)/../../utility/include \
-    $(LOCAL_PATH)/../../../../system_wrappers/interface 
+    $(LOCAL_PATH)/../../../../system_wrappers/interface
 
 LOCAL_SHARED_LIBRARIES := \
     libcutils \
diff --git a/webrtc/modules/video_coding/main/source/timestamp_extrapolator.cc b/webrtc/modules/video_coding/main/source/timestamp_extrapolator.cc
deleted file mode 100644
index bde2f0a..0000000
--- a/webrtc/modules/video_coding/main/source/timestamp_extrapolator.cc
+++ /dev/null
@@ -1,231 +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/timestamp_extrapolator.h"
-
-#include <algorithm>
-
-namespace webrtc {
-
-VCMTimestampExtrapolator::VCMTimestampExtrapolator(int64_t start_ms)
-    : _rwLock(RWLockWrapper::CreateRWLock()),
-      _startMs(0),
-      _firstTimestamp(0),
-      _wrapArounds(0),
-      _prevUnwrappedTimestamp(-1),
-      _prevWrapTimestamp(-1),
-      _lambda(1),
-      _firstAfterReset(true),
-      _packetCount(0),
-      _startUpFilterDelayInPackets(2),
-      _detectorAccumulatorPos(0),
-      _detectorAccumulatorNeg(0),
-      _alarmThreshold(60e3),
-      _accDrift(6600),  // in timestamp ticks, i.e. 15 ms
-      _accMaxError(7000),
-      _P11(1e10) {
-    Reset(start_ms);
-}
-
-VCMTimestampExtrapolator::~VCMTimestampExtrapolator()
-{
-    delete _rwLock;
-}
-
-void
-VCMTimestampExtrapolator::Reset(int64_t start_ms)
-{
-    WriteLockScoped wl(*_rwLock);
-    _startMs = start_ms;
-    _prevMs = _startMs;
-    _firstTimestamp = 0;
-    _w[0] = 90.0;
-    _w[1] = 0;
-    _P[0][0] = 1;
-    _P[1][1] = _P11;
-    _P[0][1] = _P[1][0] = 0;
-    _firstAfterReset = true;
-    _prevUnwrappedTimestamp = -1;
-    _prevWrapTimestamp = -1;
-    _wrapArounds = 0;
-    _packetCount = 0;
-    _detectorAccumulatorPos = 0;
-    _detectorAccumulatorNeg = 0;
-}
-
-void
-VCMTimestampExtrapolator::Update(int64_t tMs, uint32_t ts90khz)
-{
-
-    _rwLock->AcquireLockExclusive();
-    if (tMs - _prevMs > 10e3)
-    {
-        // Ten seconds without a complete frame.
-        // Reset the extrapolator
-        _rwLock->ReleaseLockExclusive();
-        Reset(tMs);
-        _rwLock->AcquireLockExclusive();
-    }
-    else
-    {
-        _prevMs = tMs;
-    }
-
-    // Remove offset to prevent badly scaled matrices
-    tMs -= _startMs;
-
-    CheckForWrapArounds(ts90khz);
-
-    int64_t unwrapped_ts90khz = static_cast<int64_t>(ts90khz) +
-        _wrapArounds * ((static_cast<int64_t>(1) << 32) - 1);
-
-    if (_prevUnwrappedTimestamp >= 0 &&
-        unwrapped_ts90khz < _prevUnwrappedTimestamp)
-    {
-        // Drop reordered frames.
-        _rwLock->ReleaseLockExclusive();
-        return;
-    }
-
-    if (_firstAfterReset)
-    {
-        // Make an initial guess of the offset,
-        // should be almost correct since tMs - _startMs
-        // should about zero at this time.
-        _w[1] = -_w[0] * tMs;
-        _firstTimestamp = unwrapped_ts90khz;
-        _firstAfterReset = false;
-    }
-
-    double residual =
-        (static_cast<double>(unwrapped_ts90khz) - _firstTimestamp) -
-        static_cast<double>(tMs) * _w[0] - _w[1];
-    if (DelayChangeDetection(residual) &&
-        _packetCount >= _startUpFilterDelayInPackets)
-    {
-        // A sudden change of average network delay has been detected.
-        // Force the filter to adjust its offset parameter by changing
-        // the offset uncertainty. Don't do this during startup.
-        _P[1][1] = _P11;
-    }
-    //T = [t(k) 1]';
-    //that = T'*w;
-    //K = P*T/(lambda + T'*P*T);
-    double K[2];
-    K[0] = _P[0][0] * tMs + _P[0][1];
-    K[1] = _P[1][0] * tMs + _P[1][1];
-    double TPT = _lambda + tMs * K[0] + K[1];
-    K[0] /= TPT;
-    K[1] /= TPT;
-    //w = w + K*(ts(k) - that);
-    _w[0] = _w[0] + K[0] * residual;
-    _w[1] = _w[1] + K[1] * residual;
-    //P = 1/lambda*(P - K*T'*P);
-    double p00 = 1 / _lambda * (_P[0][0] - (K[0] * tMs * _P[0][0] + K[0] * _P[1][0]));
-    double p01 = 1 / _lambda * (_P[0][1] - (K[0] * tMs * _P[0][1] + K[0] * _P[1][1]));
-    _P[1][0] = 1 / _lambda * (_P[1][0] - (K[1] * tMs * _P[0][0] + K[1] * _P[1][0]));
-    _P[1][1] = 1 / _lambda * (_P[1][1] - (K[1] * tMs * _P[0][1] + K[1] * _P[1][1]));
-    _P[0][0] = p00;
-    _P[0][1] = p01;
-    _prevUnwrappedTimestamp = unwrapped_ts90khz;
-    if (_packetCount < _startUpFilterDelayInPackets)
-    {
-        _packetCount++;
-    }
-    _rwLock->ReleaseLockExclusive();
-}
-
-int64_t
-VCMTimestampExtrapolator::ExtrapolateLocalTime(uint32_t timestamp90khz)
-{
-    ReadLockScoped rl(*_rwLock);
-    int64_t localTimeMs = 0;
-    CheckForWrapArounds(timestamp90khz);
-    double unwrapped_ts90khz = static_cast<double>(timestamp90khz) +
-        _wrapArounds * ((static_cast<int64_t>(1) << 32) - 1);
-    if (_packetCount == 0)
-    {
-        localTimeMs = -1;
-    }
-    else if (_packetCount < _startUpFilterDelayInPackets)
-    {
-        localTimeMs = _prevMs + static_cast<int64_t>(
-            static_cast<double>(unwrapped_ts90khz - _prevUnwrappedTimestamp) /
-            90.0 + 0.5);
-    }
-    else
-    {
-        if (_w[0] < 1e-3)
-        {
-            localTimeMs = _startMs;
-        }
-        else
-        {
-            double timestampDiff = unwrapped_ts90khz -
-                static_cast<double>(_firstTimestamp);
-            localTimeMs = static_cast<int64_t>(
-                static_cast<double>(_startMs) + (timestampDiff - _w[1]) /
-                _w[0] + 0.5);
-        }
-    }
-    return localTimeMs;
-}
-
-// Investigates if the timestamp clock has overflowed since the last timestamp and
-// keeps track of the number of wrap arounds since reset.
-void
-VCMTimestampExtrapolator::CheckForWrapArounds(uint32_t ts90khz)
-{
-    if (_prevWrapTimestamp == -1)
-    {
-        _prevWrapTimestamp = ts90khz;
-        return;
-    }
-    if (ts90khz < _prevWrapTimestamp)
-    {
-        // This difference will probably be less than -2^31 if we have had a wrap around
-        // (e.g. timestamp = 1, _previousTimestamp = 2^32 - 1). Since it is casted to a Word32,
-        // it should be positive.
-        if (static_cast<int32_t>(ts90khz - _prevWrapTimestamp) > 0)
-        {
-            // Forward wrap around
-            _wrapArounds++;
-        }
-    }
-    // This difference will probably be less than -2^31 if we have had a backward wrap around.
-    // Since it is casted to a Word32, it should be positive.
-    else if (static_cast<int32_t>(_prevWrapTimestamp - ts90khz) > 0)
-    {
-        // Backward wrap around
-        _wrapArounds--;
-    }
-    _prevWrapTimestamp = ts90khz;
-}
-
-bool
-VCMTimestampExtrapolator::DelayChangeDetection(double error)
-{
-    // CUSUM detection of sudden delay changes
-    error = (error > 0) ? std::min(error, _accMaxError) :
-                          std::max(error, -_accMaxError);
-    _detectorAccumulatorPos =
-        std::max(_detectorAccumulatorPos + error - _accDrift, (double)0);
-    _detectorAccumulatorNeg =
-        std::min(_detectorAccumulatorNeg + error + _accDrift, (double)0);
-    if (_detectorAccumulatorPos > _alarmThreshold || _detectorAccumulatorNeg < -_alarmThreshold)
-    {
-        // Alarm
-        _detectorAccumulatorPos = _detectorAccumulatorNeg = 0;
-        return true;
-    }
-    return false;
-}
-
-}
diff --git a/webrtc/modules/video_coding/main/source/timestamp_extrapolator.h b/webrtc/modules/video_coding/main/source/timestamp_extrapolator.h
deleted file mode 100644
index 151e4de..0000000
--- a/webrtc/modules/video_coding/main/source/timestamp_extrapolator.h
+++ /dev/null
@@ -1,56 +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.
- */
-
-#ifndef WEBRTC_MODULES_VIDEO_CODING_TIMESTAMP_EXTRAPOLATOR_H_
-#define WEBRTC_MODULES_VIDEO_CODING_TIMESTAMP_EXTRAPOLATOR_H_
-
-#include "webrtc/system_wrappers/interface/rw_lock_wrapper.h"
-#include "webrtc/typedefs.h"
-
-namespace webrtc
-{
-
-class VCMTimestampExtrapolator
-{
-public:
-    explicit VCMTimestampExtrapolator(int64_t start_ms);
-    ~VCMTimestampExtrapolator();
-    void Update(int64_t tMs, uint32_t ts90khz);
-    int64_t ExtrapolateLocalTime(uint32_t timestamp90khz);
-    void Reset(int64_t start_ms);
-
-private:
-    void CheckForWrapArounds(uint32_t ts90khz);
-    bool DelayChangeDetection(double error);
-    RWLockWrapper*        _rwLock;
-    double                _w[2];
-    double                _P[2][2];
-    int64_t         _startMs;
-    int64_t         _prevMs;
-    uint32_t        _firstTimestamp;
-    int32_t         _wrapArounds;
-    int64_t         _prevUnwrappedTimestamp;
-    int64_t         _prevWrapTimestamp;
-    const double          _lambda;
-    bool                  _firstAfterReset;
-    uint32_t        _packetCount;
-    const uint32_t  _startUpFilterDelayInPackets;
-
-    double              _detectorAccumulatorPos;
-    double              _detectorAccumulatorNeg;
-    const double        _alarmThreshold;
-    const double        _accDrift;
-    const double        _accMaxError;
-    const double        _P11;
-};
-
-}  // namespace webrtc
-
-#endif // WEBRTC_MODULES_VIDEO_CODING_TIMESTAMP_EXTRAPOLATOR_H_
diff --git a/webrtc/modules/video_coding/main/source/timing.cc b/webrtc/modules/video_coding/main/source/timing.cc
index dd82187..af0e35c 100644
--- a/webrtc/modules/video_coding/main/source/timing.cc
+++ b/webrtc/modules/video_coding/main/source/timing.cc
@@ -10,12 +10,10 @@
 
 #include "webrtc/modules/video_coding/main/source/timing.h"
 
-
 #include "webrtc/modules/video_coding/main/source/internal_defines.h"
 #include "webrtc/modules/video_coding/main/source/jitter_buffer_common.h"
-#include "webrtc/modules/video_coding/main/source/timestamp_extrapolator.h"
 #include "webrtc/system_wrappers/interface/clock.h"
-
+#include "webrtc/system_wrappers/interface/timestamp_extrapolator.h"
 
 
 namespace webrtc {
@@ -35,8 +33,7 @@
       prev_frame_timestamp_(0) {
   if (master_timing == NULL) {
     master_ = true;
-    ts_extrapolator_ =
-        new VCMTimestampExtrapolator(clock_->TimeInMilliseconds());
+    ts_extrapolator_ = new TimestampExtrapolator(clock_->TimeInMilliseconds());
   } else {
     ts_extrapolator_ = master_timing->ts_extrapolator_;
   }
diff --git a/webrtc/modules/video_coding/main/source/timing.h b/webrtc/modules/video_coding/main/source/timing.h
index fcb0402..1dca5e6 100644
--- a/webrtc/modules/video_coding/main/source/timing.h
+++ b/webrtc/modules/video_coding/main/source/timing.h
@@ -18,7 +18,7 @@
 namespace webrtc {
 
 class Clock;
-class VCMTimestampExtrapolator;
+class TimestampExtrapolator;
 
 class VCMTiming {
  public:
@@ -101,7 +101,7 @@
   CriticalSectionWrapper* crit_sect_;
   Clock* clock_;
   bool master_;
-  VCMTimestampExtrapolator* ts_extrapolator_;
+  TimestampExtrapolator* ts_extrapolator_;
   VCMCodecTimer codec_timer_;
   uint32_t render_delay_ms_;
   uint32_t min_playout_delay_ms_;
diff --git a/webrtc/modules/video_coding/main/source/video_coding.gypi b/webrtc/modules/video_coding/main/source/video_coding.gypi
index b4f6cb7..f19a585 100644
--- a/webrtc/modules/video_coding/main/source/video_coding.gypi
+++ b/webrtc/modules/video_coding/main/source/video_coding.gypi
@@ -48,7 +48,6 @@
         'receiver.h',
         'rtt_filter.h',
         'session_info.h',
-        'timestamp_extrapolator.h',
         'timestamp_map.h',
         'timing.h',
         'video_coding_impl.h',
@@ -72,7 +71,6 @@
         'receiver.cc',
         'rtt_filter.cc',
         'session_info.cc',
-        'timestamp_extrapolator.cc',
         'timestamp_map.cc',
         'timing.cc',
         'video_coding_impl.cc',