[haiku-commits] r34682 - haiku/trunk/src/add-ons/media/media-add-ons/multi_audio
- From: ingo_weinhold@xxxxxx
- To: haiku-commits@xxxxxxxxxxxxx
- Date: Wed, 16 Dec 2009 21:04:58 +0100 (CET)
Author: bonefish
Date: 2009-12-16 21:04:58 +0100 (Wed, 16 Dec 2009)
New Revision: 34682
Changeset: http://dev.haiku-os.org/changeset/34682/haiku
Added:
haiku/trunk/src/add-ons/media/media-add-ons/multi_audio/TimeComputer.cpp
haiku/trunk/src/add-ons/media/media-add-ons/multi_audio/TimeComputer.h
Modified:
haiku/trunk/src/add-ons/media/media-add-ons/multi_audio/Jamfile
Log:
Added support class TimeComputer to compute smoother performance times.
Modified: haiku/trunk/src/add-ons/media/media-add-ons/multi_audio/Jamfile
===================================================================
--- haiku/trunk/src/add-ons/media/media-add-ons/multi_audio/Jamfile
2009-12-16 12:51:26 UTC (rev 34681)
+++ haiku/trunk/src/add-ons/media/media-add-ons/multi_audio/Jamfile
2009-12-16 20:04:58 UTC (rev 34682)
@@ -13,6 +13,7 @@
MultiAudioDevice.cpp
MultiAudioNode.cpp
MultiAudioUtility.cpp
+ TimeComputer.cpp
: be media $(TARGET_LIBSUPC++)
;
Added: haiku/trunk/src/add-ons/media/media-add-ons/multi_audio/TimeComputer.cpp
===================================================================
--- haiku/trunk/src/add-ons/media/media-add-ons/multi_audio/TimeComputer.cpp
(rev 0)
+++ haiku/trunk/src/add-ons/media/media-add-ons/multi_audio/TimeComputer.cpp
2009-12-16 20:04:58 UTC (rev 34682)
@@ -0,0 +1,94 @@
+/*
+ * Copyright 2009, Ingo Weinhold, ingo_weinhold@xxxxxxx
+ * Distributed under the terms of the MIT License.
+ */
+
+
+#include "TimeComputer.h"
+
+
+TimeComputer::TimeComputer()
+ :
+ fRealTime(0),
+ fPerformanceTime(0),
+ fDrift(1),
+ fFrameRate(1000000),
+ fUsecsPerFrame(1),
+ fPerformanceTimeBase(0),
+ fFrameBase(0),
+ fResetTimeBase(true),
+ fFirstEntry(0),
+ fLastEntry(0)
+{
+}
+
+
+void
+TimeComputer::Init(float frameRate, bigtime_t realBaseTime)
+{
+ fRealTime = realBaseTime;
+ fPerformanceTime = 0;
+ fDrift = 1;
+ SetFrameRate(frameRate);
+}
+
+
+void
+TimeComputer::SetFrameRate(float frameRate)
+{
+ if (frameRate == fFrameRate)
+ return;
+
+ fFrameRate = frameRate;
+ fUsecsPerFrame = (double)1000000 / fFrameRate;
+ fResetTimeBase = true;
+ fFirstEntry = 0;
+ fLastEntry = 0;
+}
+
+
+void
+TimeComputer::AddTimeStamp(bigtime_t realTime, uint64 frames)
+{
+ bigtime_t estimatedPerformanceTime = fPerformanceTime
+ + bigtime_t((realTime - fRealTime) * fDrift);
+
+ fRealTime = realTime;
+
+ if (fResetTimeBase) {
+ // use the extrapolated performance time at the given real time
+ fPerformanceTime = estimatedPerformanceTime;
+ fPerformanceTimeBase = estimatedPerformanceTime;
+ fFrameBase = frames;
+ fResetTimeBase = false;
+ _AddEntry(fRealTime, fPerformanceTime);
+ return;
+ }
+
+ // add entry
+ bigtime_t performanceTime = fPerformanceTimeBase
+ + bigtime_t((frames - fFrameBase) * fUsecsPerFrame);
+ _AddEntry(realTime, performanceTime);
+
+ // Update performance time and drift. We don't use the given
+ // performance time directly, but average it with the estimated
+ // performance time.
+ fPerformanceTime = (performanceTime + estimatedPerformanceTime) / 2;
+
+ Entry& entry = fEntries[fFirstEntry];
+ fDrift = double(fPerformanceTime - entry.performanceTime)
+ / double(fRealTime - entry.realTime);
+}
+
+
+void
+TimeComputer::_AddEntry(bigtime_t realTime, bigtime_t performanceTime)
+{
+ fLastEntry = (fLastEntry + 1) % kEntryCount;
+ Entry& entry = fEntries[fLastEntry];
+ entry.realTime = realTime;
+ entry.performanceTime = performanceTime;
+
+ if (fLastEntry == fFirstEntry)
+ fFirstEntry = (fFirstEntry + 1) % kEntryCount;
+}
Added: haiku/trunk/src/add-ons/media/media-add-ons/multi_audio/TimeComputer.h
===================================================================
--- haiku/trunk/src/add-ons/media/media-add-ons/multi_audio/TimeComputer.h
(rev 0)
+++ haiku/trunk/src/add-ons/media/media-add-ons/multi_audio/TimeComputer.h
2009-12-16 20:04:58 UTC (rev 34682)
@@ -0,0 +1,52 @@
+/*
+ * Copyright 2009, Ingo Weinhold, ingo_weinhold@xxxxxxx
+ * Distributed under the terms of the MIT License.
+ */
+#ifndef TIME_COMPUTER_H
+#define TIME_COMPUTER_H
+
+
+#include <SupportDefs.h>
+
+
+struct TimeComputer {
+ TimeComputer();
+
+ void Init(float frameRate,
bigtime_t realBaseTime);
+ void SetFrameRate(float
frameRate);
+
+ void AddTimeStamp(bigtime_t
realTime, uint64 frames);
+
+ bigtime_t RealTime() const
{ return fRealTime; }
+ bigtime_t PerformanceTime() const
+ {
return fPerformanceTime; }
+ double Drift() const
{ return fDrift; }
+
+private:
+ static const int32 kEntryCount = 32;
+
+ struct Entry {
+ bigtime_t realTime;
+ bigtime_t performanceTime;
+ };
+
+private:
+ void _AddEntry(bigtime_t
realTime,
+
bigtime_t performanceTime);
+
+private:
+ bigtime_t fRealTime;
+ bigtime_t fPerformanceTime;
+ double fDrift;
+ float fFrameRate;
+ double fUsecsPerFrame;
+ bigtime_t fPerformanceTimeBase;
+ uint64 fFrameBase;
+ bool fResetTimeBase;
+ Entry fEntries[kEntryCount];
+ int32 fFirstEntry;
+ int32 fLastEntry;
+};
+
+
+#endif // TIME_COMPUTER_H
Other related posts:
- » [haiku-commits] r34682 - haiku/trunk/src/add-ons/media/media-add-ons/multi_audio - ingo_weinhold
