timebase.cpp

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/* SPDX-License-Identifier: MIT */
#include "ajabase/common/common.h"
#include "ajabase/common/timebase.h"
#include "ajabase/system/systemtime.h"
 
struct AJAFrameRateEntry
{
    AJA_FrameRate ajaFrameRate;
    int64_t       frameTimeScale;
    int64_t       frameDuration;
};
const AJAFrameRateEntry AJAFrameRateTable[] =
{
    {AJA_FrameRate_1498, 15000, 1001},
    {AJA_FrameRate_1500, 15000, 1000},
    {AJA_FrameRate_1798, 18000, 1001},
    {AJA_FrameRate_1800, 18000, 1000},
    {AJA_FrameRate_1898, 19000, 1001},
    {AJA_FrameRate_1900, 19000, 1000},
    {AJA_FrameRate_2398, 24000, 1001},
    {AJA_FrameRate_2400, 24000, 1000},
    {AJA_FrameRate_2500, 25000, 1000},
    {AJA_FrameRate_2997, 30000, 1001},
    {AJA_FrameRate_3000, 30000, 1000},
    {AJA_FrameRate_4795, 48000, 1001},
    {AJA_FrameRate_4800, 48000, 1000},
    {AJA_FrameRate_5000, 50000, 1000},
    {AJA_FrameRate_5994, 60000, 1001},
    {AJA_FrameRate_6000, 60000, 1000},
    {AJA_FrameRate_10000,100000,1000},
    {AJA_FrameRate_11988,120000,1001},
    {AJA_FrameRate_12000,120000,1000}
};
const size_t AJAFrameRateTableSize = sizeof(AJAFrameRateTable) / sizeof(AJAFrameRateEntry);
 
const int64_t AJATimeBaseDefaultTimeScale = 30000;
const int64_t AJATimeBaseDefaultDuration  = 1001;
const int64_t AJATimeBaseDefaultAudioRate = 48000;
 
AJATimeBase::AJATimeBase()
{
    SetToDefault();
}
 
AJATimeBase::AJATimeBase(AJA_FrameRate ajaFrameRate)
{
    SetToDefault();
    // this will set the correct timeScale and duration
    SetAJAFrameRatePrivate(ajaFrameRate);
}
 
AJATimeBase::AJATimeBase(int64_t frameTimeScale, int64_t frameDuration)
{
    SetToDefault();
    mFrameTimeScale = frameTimeScale;
    mFrameDuration  = frameDuration;
}
 
AJATimeBase::AJATimeBase(int64_t frameTimeScale, int64_t frameDuration, int64_t audioRate)
{
    SetToDefault();
    mFrameTimeScale = frameTimeScale;
    mFrameDuration  = frameDuration;
    mAudioRate      = audioRate;
}
 
AJATimeBase::AJATimeBase(const AJATimeBase &other)
{
    mFrameTimeScale = other.mFrameTimeScale;
    mFrameDuration = other.mFrameDuration;
    mAudioRate = other.mAudioRate;
    mTickRate = other.mTickRate;
}
 
AJATimeBase::~AJATimeBase()
{
}
 
void AJATimeBase::SetToDefault(void)
{
    mFrameTimeScale = AJATimeBaseDefaultTimeScale;
    mFrameDuration  = AJATimeBaseDefaultDuration;
    mAudioRate      = AJATimeBaseDefaultAudioRate;
    mTickRate       = AJATime::GetSystemFrequency();
}
 
AJATimeBase& AJATimeBase::operator=(const AJATimeBase &t)
{
    if (this != &t)
    {
        mFrameTimeScale     = t.mFrameTimeScale;
        mFrameDuration      = t.mFrameDuration;
        mAudioRate          = t.mAudioRate;
        mTickRate           = t.mTickRate;
    }
 
    return *this;
}
 
bool AJATimeBase::operator==(const AJATimeBase &b) const 
{
    bool bIsSame = true;
 
    if (mFrameTimeScale != b.mFrameTimeScale)
        bIsSame = false;
    if (mFrameDuration  != b.mFrameDuration)
        bIsSame = false;
    if (mAudioRate      != b.mAudioRate)
        bIsSame = false;
    if (mTickRate       != b.mTickRate)
        bIsSame = false;
 
    return bIsSame;
}
 
bool AJATimeBase::operator!=(const AJATimeBase &a) const 
{
    return !(*this == a);
}
 
void AJATimeBase::SetFrameRate(int64_t frameTimeScale, int64_t frameDuration)
{
    mFrameTimeScale = frameTimeScale;
    mFrameDuration = frameDuration;
}
 
void AJATimeBase::GetFrameRate(int64_t& frameTimeScale, int64_t& frameDuration) const
{
    frameTimeScale = mFrameTimeScale;
    frameDuration = mFrameDuration;
}
 
int64_t AJATimeBase::GetFrameTimeScale(void) const
{
    return mFrameTimeScale;
}
 
void AJATimeBase::SetFrameTimeScale(int64_t timeScale)
{
    mFrameTimeScale = timeScale;
}
 
int64_t AJATimeBase::GetFrameDuration(void) const
{
    return mFrameDuration;
}
 
void AJATimeBase::SetAudioRate(int64_t rate)
{
    mAudioRate = rate;
}
 
int64_t AJATimeBase::GetAudioRate() const
{
    return mAudioRate;
}
 
void AJATimeBase::SetAJAFrameRate(AJA_FrameRate ajaFrameRate)
{
    SetAJAFrameRatePrivate(ajaFrameRate);
}
 
void AJATimeBase::SetTickRate(int64_t rate)
{
    if (rate == 0)
    {
        // set to native rate
        mTickRate = AJATime::GetSystemFrequency();
    }
    else
    {
        mTickRate = rate;
    }
}
 
int64_t AJATimeBase::GetTickRate() const
{
    return mTickRate;
}
 
int64_t AJATimeBase::FramesToSamples(int64_t frames, bool round) const
{
    return Convert(frames, mFrameTimeScale, mFrameDuration, mAudioRate, 1, round, true);
}
 
int64_t AJATimeBase::FramesToTicks(int64_t frames, bool round) const
{
    return Convert(frames, mFrameTimeScale, mFrameDuration, mTickRate, 1, round, true);
}
 
double AJATimeBase::FramesToSeconds(int64_t frames) const
{
    return (double)frames * (double)mFrameDuration / (double)mFrameTimeScale;
}
 
double AJATimeBase::ScaleUnitsToSeconds(int64_t scaleUnits) const
{
    return (double)scaleUnits / (double)mFrameTimeScale;
}
 
float AJATimeBase::GetFramesPerSecond(void) const
{
    float val = 0.f;
    if (mFrameDuration)
        val = (float)mFrameTimeScale / (float)mFrameDuration;
    return val;
}
 
double AJATimeBase::GetFramesPerSecondDouble(void) const
{
    double val = 0.;
    if (mFrameDuration)
        val = (double)mFrameTimeScale / (double)mFrameDuration;
    return val;
}
 
int64_t AJATimeBase::FramesToMicroseconds(int64_t frames, bool round) const
{
    return Convert(frames, mFrameTimeScale, mFrameDuration, 1000000, 1, round, true);
}
 
int64_t AJATimeBase::FramesToNanoseconds100(int64_t frames, bool round) const
{
    return Convert(frames, mFrameTimeScale, mFrameDuration, 10000000, 1, round, true);
}
 
int64_t AJATimeBase::SamplesToFrames(int64_t samples, bool round) const
{
    return Convert(samples, mAudioRate, 1, mFrameTimeScale, mFrameDuration, round, true);
}
 
int64_t AJATimeBase::SamplesToTicks(int64_t samples, bool round) const
{
    return Convert(samples, mAudioRate, mTickRate, round, true);
}
 
double AJATimeBase::SamplesToSeconds(int64_t samples)
{
    return (double)samples / (double)mAudioRate;
}
 
int64_t AJATimeBase::SamplesToMicroseconds(int64_t samples, bool round)
{
    return Convert(samples, mAudioRate, 1000000, round, true);
}
 
int64_t AJATimeBase::TicksToFrames(int64_t ticks, bool round)
{
    return Convert(ticks, mTickRate, 1, mFrameTimeScale, mFrameDuration, round, true);
}
 
int64_t AJATimeBase::TicksToSamples(int64_t ticks, bool round)
{
    return Convert(ticks, mTickRate, mAudioRate, round, true);
}
 
double AJATimeBase::TicksToSeconds(int64_t ticks)
{
    return (double)ticks / (double)mTickRate;
}
 
int64_t AJATimeBase::TicksToMicroseconds(int64_t ticks, bool round)
{
    return Convert(ticks, mTickRate, 1000000, round, true);
}
 
int64_t AJATimeBase::SecondsToFrames(double seconds, bool round)
{
    return Convert((int64_t)(seconds * 1000000000.0), 1000000000, 1, mFrameTimeScale, mFrameDuration, round, true);
}
 
int64_t AJATimeBase::SecondsToSamples(double seconds, bool round)
{
    return Convert((int64_t)(seconds * 1000000000.0), 1000000000, mAudioRate, round, true);
}
 
int64_t AJATimeBase::SecondsToTicks(double seconds, bool round)
{
    return Convert((int64_t)(seconds * 1000000000.0), 1000000000, mTickRate, round, true);
}
 
int64_t AJATimeBase::MicrosecondsToFrames(int64_t microseconds, bool round)
{
    return Convert(microseconds, 1000000, 1, mFrameTimeScale, mFrameDuration, round, true);
}
 
int64_t AJATimeBase::Nanoseconds100ToFrames(int64_t nanoseconds100, bool round)
{
    return Convert(nanoseconds100, 10000000, 1, mFrameTimeScale, mFrameDuration, round, true);
}
 
int64_t AJATimeBase::MicrosecondsToSamples(int64_t microseconds, bool round)
{
    return Convert(microseconds, 1000000, mAudioRate, round, true);
}
 
int64_t AJATimeBase::MicrosecondsToTicks(int64_t microseconds, bool round)
{
    return Convert(microseconds, 1000000, mTickRate, round, true);
}
 
int64_t AJATimeBase::SecondsToMicroseconds(double seconds, bool round)
{
    return Convert((int64_t)(seconds * 1000000.0), 1000000, 1000000, round, false);
}
 
double AJATimeBase::MicrosecondsToSeconds(int64_t microseconds)
{
    return (double)microseconds / 1000000.0;
}
 
bool AJATimeBase::IsCloseTo(const AJATimeBase &timeBase) const
{
    bool bIsClose = false;
    double rate1  = FramesToSeconds(1);
    double rate2  = timeBase.FramesToSeconds(1);
    double dif    = rate1 / rate2;
 
            // this is just a guess at what is considered close enough
            // it will differentiate between 30000/1001 and 30000/1000,
            // but 2997/100 is *not* close to 30000/1001
    if ((dif >= .9999) && (dif <= 1.0001))
        bIsClose = true;
    return bIsClose;
}
 
bool AJATimeBase::IsCloseTo(int64_t frameTimeScale, int64_t frameDuration) const
{
    AJATimeBase tb(frameTimeScale,frameDuration);
    return IsCloseTo(tb);
}
 
bool AJATimeBase::IsNonIntegralRatio (void) const
{
    return ((mFrameTimeScale % mFrameDuration) != 0) ? true : false;
}
 
int64_t AJATimeBase::GetSystemTicks()
{
    int64_t ticks = AJATime::GetSystemCounter();
    int64_t rate = AJATime::GetSystemFrequency();
 
    if (rate != mTickRate)
    {
        ticks = Convert(ticks, rate, mTickRate, false, true);
    }
 
    return ticks;
}
 
int64_t AJATimeBase:: Convert(int64_t inValue, int64_t inRate, int64_t outRate, bool round, bool large)
{
    int64_t outValue = 0;
 
    if (round)
    {
        // convert half the out rate to the in rate and increase the in value
        int64_t roundValue = inRate / (outRate * 2);
        if (inValue > 0)
        {
            inValue += roundValue;
        }
        else
        {
            inValue -= roundValue;
        }
    }
 
    if (large)
    {
        // this will not overflow
        outValue = inValue / inRate * outRate;
        outValue += (inValue % inRate) * outRate / inRate;
    }
    else
    {
        // this has better performance
        outValue = inValue * outRate / inRate;
    }
 
    return outValue;
}
 
int64_t AJATimeBase::Convert(int64_t inValue, int64_t inScale, int64_t inDuration,
                             int64_t outScale, int64_t outDuration, bool round, bool large)
{
    int64_t outValue = 0;
    int64_t roundValue = 0;
    int64_t inScaleOutDuration = inScale * outDuration;
    int64_t outScaleInDuration = outScale * inDuration;
 
    if (round)
    {
        // convert half the out scale to the in duration and increase the in value
        roundValue = inScaleOutDuration / (outScaleInDuration * 2);
        if (inValue > 0)
        {
            inValue += roundValue;
        }
        else
        {
            inValue -= roundValue;
        }
    }
 
    if (large)
    {
        // this will not overflow
        outValue = inValue / inScaleOutDuration * outScaleInDuration;
        outValue += (inValue % inScaleOutDuration) * outScaleInDuration / inScaleOutDuration;
    }
    else
    {
        // this has better performance
        outValue = inValue * outScaleInDuration / inScaleOutDuration;
    }
 
    return outValue;
}
 
AJA_FrameRate AJATimeBase::GetAJAFrameRate(void) const
{
    AJA_FrameRate fr = AJA_FrameRate_Unknown;
    for (size_t i = 0; i < AJAFrameRateTableSize; i++)
    {
        if (IsCloseTo(AJAFrameRateTable[i].frameTimeScale,AJAFrameRateTable[i].frameDuration))
        {
            fr = AJAFrameRateTable[i].ajaFrameRate;
            break;
        }
    }
     
    return fr;
}
 
void AJATimeBase::SetAJAFrameRatePrivate(AJA_FrameRate ajaFrameRate)
{
    mFrameTimeScale = AJATimeBaseDefaultTimeScale;
    mFrameDuration  = AJATimeBaseDefaultDuration;
 
    for (size_t i = 0; i < AJAFrameRateTableSize; i++)
    {
        if (AJAFrameRateTable[i].ajaFrameRate == ajaFrameRate)
        {
            mFrameTimeScale = AJAFrameRateTable[i].frameTimeScale;
            mFrameDuration  = AJAFrameRateTable[i].frameDuration;
            break;
        }
    }
}