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-rw-r--r--chromium/third_party/webrtc/modules/video_coding/main/source/timestamp_extrapolator.cc248
1 files changed, 0 insertions, 248 deletions
diff --git a/chromium/third_party/webrtc/modules/video_coding/main/source/timestamp_extrapolator.cc b/chromium/third_party/webrtc/modules/video_coding/main/source/timestamp_extrapolator.cc
deleted file mode 100644
index 1d911a54e44..00000000000
--- a/chromium/third_party/webrtc/modules/video_coding/main/source/timestamp_extrapolator.cc
+++ /dev/null
@@ -1,248 +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/timestamp_extrapolator.h"
-#include "webrtc/system_wrappers/interface/clock.h"
-#include "webrtc/system_wrappers/interface/trace.h"
-
-namespace webrtc {
-
-VCMTimestampExtrapolator::VCMTimestampExtrapolator(Clock* clock,
- int32_t vcmId,
- int32_t id)
-:
-_rwLock(RWLockWrapper::CreateRWLock()),
-_vcmId(vcmId),
-_id(id),
-_clock(clock),
-_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();
-}
-
-VCMTimestampExtrapolator::~VCMTimestampExtrapolator()
-{
- delete _rwLock;
-}
-
-void
-VCMTimestampExtrapolator::Reset()
-{
- WriteLockScoped wl(*_rwLock);
- _startMs = _clock->TimeInMilliseconds();
- _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, bool trace)
-{
-
- _rwLock->AcquireLockExclusive();
- if (tMs - _prevMs > 10e3)
- {
- // Ten seconds without a complete frame.
- // Reset the extrapolator
- _rwLock->ReleaseLockExclusive();
- Reset();
- _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, trace) &&
- _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++;
- }
- if (trace)
- {
- WEBRTC_TRACE(webrtc::kTraceDebug, webrtc::kTraceVideoCoding, VCMId(_vcmId, _id), "w[0]=%f w[1]=%f ts=%u tMs=%u", _w[0], _w[1], ts90khz, tMs);
- }
- _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, bool trace)
-{
- // CUSUM detection of sudden delay changes
- error = (error > 0) ? VCM_MIN(error, _accMaxError) : VCM_MAX(error, -_accMaxError);
- _detectorAccumulatorPos = VCM_MAX(_detectorAccumulatorPos + error - _accDrift, (double)0);
- _detectorAccumulatorNeg = VCM_MIN(_detectorAccumulatorNeg + error + _accDrift, (double)0);
- if (_detectorAccumulatorPos > _alarmThreshold || _detectorAccumulatorNeg < -_alarmThreshold)
- {
- // Alarm
- if (trace)
- {
- WEBRTC_TRACE(webrtc::kTraceDebug, webrtc::kTraceVideoCoding, VCMId(_vcmId, _id), "g1=%f g2=%f alarm=1", _detectorAccumulatorPos, _detectorAccumulatorNeg);
- }
- _detectorAccumulatorPos = _detectorAccumulatorNeg = 0;
- return true;
- }
- if (trace)
- {
- WEBRTC_TRACE(webrtc::kTraceDebug, webrtc::kTraceVideoCoding, VCMId(_vcmId, _id), "g1=%f g2=%f alarm=0", _detectorAccumulatorPos, _detectorAccumulatorNeg);
- }
- return false;
-}
-
-}
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