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Diffstat (limited to 'libs/appleutility/CoreAudio/AudioUnits/AUPublic/Utility/AUTimestampGenerator.h')
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diff --git a/libs/appleutility/CoreAudio/AudioUnits/AUPublic/Utility/AUTimestampGenerator.h b/libs/appleutility/CoreAudio/AudioUnits/AUPublic/Utility/AUTimestampGenerator.h new file mode 100644 index 0000000000..cfd8456dfb --- /dev/null +++ b/libs/appleutility/CoreAudio/AudioUnits/AUPublic/Utility/AUTimestampGenerator.h @@ -0,0 +1,163 @@ +/* + File: AUTimestampGenerator.h + Abstract: Part of CoreAudio Utility Classes + Version: 1.1 + + Disclaimer: IMPORTANT: This Apple software is supplied to you by Apple + Inc. ("Apple") in consideration of your agreement to the following + terms, and your use, installation, modification or redistribution of + this Apple software constitutes acceptance of these terms. If you do + not agree with these terms, please do not use, install, modify or + redistribute this Apple software. + + In consideration of your agreement to abide by the following terms, and + subject to these terms, Apple grants you a personal, non-exclusive + license, under Apple's copyrights in this original Apple software (the + "Apple Software"), to use, reproduce, modify and redistribute the Apple + Software, with or without modifications, in source and/or binary forms; + provided that if you redistribute the Apple Software in its entirety and + without modifications, you must retain this notice and the following + text and disclaimers in all such redistributions of the Apple Software. + Neither the name, trademarks, service marks or logos of Apple Inc. may + be used to endorse or promote products derived from the Apple Software + without specific prior written permission from Apple. Except as + expressly stated in this notice, no other rights or licenses, express or + implied, are granted by Apple herein, including but not limited to any + patent rights that may be infringed by your derivative works or by other + works in which the Apple Software may be incorporated. + + The Apple Software is provided by Apple on an "AS IS" basis. APPLE + MAKES NO WARRANTIES, EXPRESS OR IMPLIED, INCLUDING WITHOUT LIMITATION + THE IMPLIED WARRANTIES OF NON-INFRINGEMENT, MERCHANTABILITY AND FITNESS + FOR A PARTICULAR PURPOSE, REGARDING THE APPLE SOFTWARE OR ITS USE AND + OPERATION ALONE OR IN COMBINATION WITH YOUR PRODUCTS. + + IN NO EVENT SHALL APPLE BE LIABLE FOR ANY SPECIAL, INDIRECT, INCIDENTAL + OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF + SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS + INTERRUPTION) ARISING IN ANY WAY OUT OF THE USE, REPRODUCTION, + MODIFICATION AND/OR DISTRIBUTION OF THE APPLE SOFTWARE, HOWEVER CAUSED + AND WHETHER UNDER THEORY OF CONTRACT, TORT (INCLUDING NEGLIGENCE), + STRICT LIABILITY OR OTHERWISE, EVEN IF APPLE HAS BEEN ADVISED OF THE + POSSIBILITY OF SUCH DAMAGE. + + Copyright (C) 2014 Apple Inc. All Rights Reserved. + +*/ +#ifndef __AUTimestampGenerator_h__ +#define __AUTimestampGenerator_h__ + +#include <math.h> +#include "CAHostTimeBase.h" +#include <stdio.h> + +#define TSGFMT "0x%10qx" +//#define TSGFMT "%10qd" + +// This class generates a continuously increasing series of timestamps based +// on a series of potentially discontinuous timestamps (as can be delivered from +// CoreAudio in the event of an overload or major engine change). +// N.B.: "output" = downstream (source) timestamp +// "input" = upstream (derived) timestamp +class AUTimestampGenerator { +public: + AUTimestampGenerator(bool hostTimeDiscontinuityCorrection = false) + { + mState.mStartInputAtZero = true; + mState.mBypassed = false; + mState.mHostTimeDiscontinuityCorrection = hostTimeDiscontinuityCorrection; +#if DEBUG + mVerbosity = 0; + snprintf(mDebugName, sizeof(mDebugName), "tsg @ %p", this); +#endif + // CAHostTimeBase should be used instead of the calls in <CoreAudio/HostTime.h> + // we make this call here to ensure that this is initialized, otherwise the first time + // you do actually call CAHostTimeBase to do work, can be on the render thread, and lead to unwanted VM faults + CAHostTimeBase::GetFrequency(); + Reset(); + } + + void SetStartInputAtZero(bool b) { mState.mStartInputAtZero = b; } + bool GetStartInputAtZero() const { return mState.mStartInputAtZero; } + + // bypassing is intended for a narrow special case. the upstream sample time will always be the same as the downstream time. + void SetBypassed(bool b) { mState.mBypassed = b; } + bool GetBypassed() const { return mState.mBypassed; } + + // Call this to reset the timeline. + void Reset() + { + mState.mCurrentInputTime.mSampleTime = 0.; + mState.mNextInputSampleTime = 0.; + mState.mCurrentOutputTime.mSampleTime = 0.; + mState.mNextOutputSampleTime = 0.; + mState.mLastOutputTime.mFlags = 0; + mState.mRateScalarAdj = 1.; + + mFirstTime = true; +#if DEBUG + if (mVerbosity) + printf("%-20.20s: Reset\n", mDebugName); +#endif + } + + // Call this once per render cycle with the downstream timestamp. + // expectedDeltaFrames is the expected difference between the current and NEXT + // downstream timestamps. + // sampleRate is the OUTPUT sample rate. + void AddOutputTime(const AudioTimeStamp &inTimeStamp, Float64 expectedDeltaFrames, double outputSampleRate, double rateScalarAdj=1.0); + + // Call this once per render cycle to obtain the upstream timestamp. + // framesToAdvance is the number of frames the input timeline is to be + // advanced during this render cycle. + // sampleRate is the INPUT sample rate. + const AudioTimeStamp & GenerateInputTime(Float64 framesToAdvance, double inputSampleRate, bool advanceHostTime = false); + + // this can be called to override the setting of the next input sample time in GenerateInputTime + void Advance(Float64 framesToAdvance) + { +#if DEBUG + if (mVerbosity > 1) + printf("%-20.20s: ADVANCE in = " TSGFMT " advance = " TSGFMT "\n", mDebugName, (SInt64)mState.mCurrentInputTime.mSampleTime, (SInt64)framesToAdvance); +#endif + mState.mNextInputSampleTime = mState.mCurrentInputTime.mSampleTime + framesToAdvance; + } + + struct State { + AudioTimeStamp mCurrentInputTime; + Float64 mNextInputSampleTime; + Float64 mNextOutputSampleTime; + Float64 mInputSampleTimeForOutputPull; + + AudioTimeStamp mLastOutputTime; + AudioTimeStamp mCurrentOutputTime; + + bool mStartInputAtZero; // if true, input timeline starts at 0, else it starts + // synced with the output timeline + bool mDiscontinuous; + bool mBypassed; + Float64 mDiscontinuityDeltaSamples; + + double mRateScalarAdj; + + bool mHostTimeDiscontinuityCorrection; // If true, propagate timestamp discontinuities using host time. + }; + + void GetState(State& outState) const { outState = mState; } + void SetState(State const& inState) { mState = inState; mFirstTime = false; } + +private: + + struct State mState; + + bool mFirstTime; + +#if DEBUG +public: + int mVerbosity; + char mDebugName[64]; +#endif +}; + + +#endif // __AUTimestampGenerator_h__ |