hyperion.ng/libsrc/hyperion/LinearColorSmoothing.cpp

// Qt includes
#include <QDateTime>
#include <QTimer>

#include <hyperion/LinearColorSmoothing.h>
#include <hyperion/Hyperion.h>

#include <cmath>
#include <chrono>
#include <thread>

#if defined(COMPILER_GCC)
#define ALWAYS_INLINE inline __attribute__((__always_inline__))
#elif defined(COMPILER_MSVC)
#define ALWAYS_INLINE __forceinline
#else
#define ALWAYS_INLINE inline
#endif

/// Clamps the rounded values to the byte-interval of [0, 255].
ALWAYS_INLINE long clampRounded(const floatT x) {
	return std::min(255L, std::max(0L, std::lroundf(x)));
}

// Constants
namespace {

const bool verbose = false;

/// The number of microseconds per millisecond = 1000.
const int64_t MS_PER_MICRO = 1000;

/// The number of bits that are used for shifting the fixed point values
const int FPShift = (sizeof(uint64_t)*8 - (12 + 9));

/// The number of bits that are reduce the shifting when converting from fixed to floating point. 8 bits = 256 values
const int SmallShiftBis = sizeof(uint8_t)*8;

/// The number of bits that are used for shifting the fixed point values plus SmallShiftBis
const int FPShiftSmall = (sizeof(uint64_t)*8 - (12 + 9 + SmallShiftBis));

const char* SETTINGS_KEY_SMOOTHING_TYPE = "type";

const char* SETTINGS_KEY_SETTLING_TIME = "time_ms";
const char* SETTINGS_KEY_UPDATE_FREQUENCY = "updateFrequency";
const char* SETTINGS_KEY_OUTPUT_DELAY = "updateDelay";

const char* SETTINGS_KEY_DECAY = "decay";
const char* SETTINGS_KEY_INTERPOLATION_RATE = "interpolationRate";
const char* SETTINGS_KEY_DITHERING = "dithering";

const int64_t DEFAULT_SETTLINGTIME = 200;	// in ms
const int DEFAULT_UPDATEFREQUENCY = 25;		// in Hz

constexpr std::chrono::milliseconds DEFAULT_UPDATEINTERVALL{MS_PER_MICRO/ DEFAULT_UPDATEFREQUENCY};
const unsigned DEFAULT_OUTPUTDEPLAY = 0;	// in frames
}

using namespace hyperion;

LinearColorSmoothing::LinearColorSmoothing(const QJsonDocument &config, Hyperion *hyperion)
	: QObject(hyperion)
	  , _log(nullptr)
	  , _hyperion(hyperion)
	  , _prioMuxer(_hyperion->getMuxerInstance())
	  , _updateInterval(DEFAULT_UPDATEINTERVALL.count())
	  , _settlingTime(DEFAULT_SETTLINGTIME)
	  , _timer(nullptr)
	  , _outputDelay(DEFAULT_OUTPUTDEPLAY)
	  , _pause(false)
	  , _currentConfigId(SmoothingConfigID::SYSTEM)
	  , _enabled(false)
	  , _enabledSystemCfg(false)
	  , _smoothingType(SmoothingType::Linear)
	  , tempValues(std::vector<uint64_t>(0, 0L))
{
	QString subComponent = hyperion->property("instance").toString();
	_log= Logger::getInstance("SMOOTHING", subComponent);

	// timer
	_timer = new QTimer(this);
	_timer->setTimerType(Qt::PreciseTimer);

	// init cfg (default)
	updateConfig(SmoothingConfigID::SYSTEM, DEFAULT_SETTLINGTIME, DEFAULT_UPDATEFREQUENCY, DEFAULT_OUTPUTDEPLAY);
	handleSettingsUpdate(settings::SMOOTHING, config);

	// add pause on cfg 1
	SmoothingCfg cfg {true, 0, 0};
	_cfgList.append(cfg);

	// listen for comp changes
	connect(_hyperion, &Hyperion::compStateChangeRequest, this, &LinearColorSmoothing::componentStateChange);
	connect(_timer, &QTimer::timeout, this, &LinearColorSmoothing::updateLeds);

	connect(_prioMuxer, &PriorityMuxer::prioritiesChanged, this, [=] (int priority){
		const PriorityMuxer::InputInfo priorityInfo = _prioMuxer->getInputInfo(priority);
		int smooth_cfg = priorityInfo.smooth_cfg;
		if (smooth_cfg != _currentConfigId || smooth_cfg == SmoothingConfigID::EFFECT_DYNAMIC)
		{
			this->selectConfig(smooth_cfg, false);
		}
	});
}

LinearColorSmoothing::~LinearColorSmoothing()
{
	delete _timer;
}

void LinearColorSmoothing::handleSettingsUpdate(settings::type type, const QJsonDocument &config)
{
	if (type == settings::type::SMOOTHING)
	{
		QJsonObject obj = config.object();

		setEnable(obj["enable"].toBool(_enabled));
		_enabledSystemCfg = _enabled;

		int64_t settlingTime_ms = static_cast<int64_t>(obj[SETTINGS_KEY_SETTLING_TIME].toInt(DEFAULT_SETTLINGTIME));
		int _updateInterval_ms =static_cast<int>(MS_PER_MICRO / obj[SETTINGS_KEY_UPDATE_FREQUENCY].toDouble(DEFAULT_UPDATEFREQUENCY));

		SmoothingCfg cfg(false, settlingTime_ms, _updateInterval_ms);

		const QString typeString = obj[SETTINGS_KEY_SMOOTHING_TYPE].toString();

		if(typeString == SETTINGS_KEY_DECAY) {
			cfg._type = SmoothingType::Decay;
		}
		else {
			cfg._type = SmoothingType::Linear;
		}

		cfg._pause = false;
		cfg._outputDelay = static_cast<unsigned>(obj[SETTINGS_KEY_OUTPUT_DELAY].toInt(DEFAULT_OUTPUTDEPLAY));

		cfg._interpolationRate = obj[SETTINGS_KEY_INTERPOLATION_RATE].toDouble(DEFAULT_UPDATEFREQUENCY);
		cfg._dithering = obj[SETTINGS_KEY_DITHERING].toBool(false);
		cfg._decay = obj[SETTINGS_KEY_DECAY].toDouble(1.0);

		_cfgList[SmoothingConfigID::SYSTEM] = cfg;
		DebugIf(_enabled,_log,"%s", QSTRING_CSTR(getConfig(SmoothingConfigID::SYSTEM)));

		// if current id is 0, we need to apply the settings (forced)
		if (_currentConfigId == SmoothingConfigID::SYSTEM)
		{
			selectConfig(SmoothingConfigID::SYSTEM, true);
		}
	}
}

int LinearColorSmoothing::write(const std::vector<ColorRgb> &ledValues)
{
	_targetTime = micros() + (MS_PER_MICRO * _settlingTime);
	_targetValues = ledValues;

	rememberFrame(ledValues);

	// received a new target color
	if (_previousValues.empty())
	{
		// not initialized yet
		_previousWriteTime = micros();
		_previousValues = ledValues;
		_previousInterpolationTime = micros();

		if (!_pause)
		{
			_timer->start(_updateInterval);
		}
	}

	return 0;
}

int LinearColorSmoothing::updateLedValues(const std::vector<ColorRgb> &ledValues)
{
	int retval = 0;
	if (!_enabled)
	{
		retval = -1;
	}
	else
	{
		retval = write(ledValues);
	}
	return retval;
}

void LinearColorSmoothing::intitializeComponentVectors(const size_t ledCount)
{
	// (Re-)Initialize the color-vectors that store the Mean-Value
	if (_ledCount != ledCount)
	{
		_ledCount = ledCount;

		const size_t len = 3 * ledCount;

		meanValues = std::vector<floatT>(len, 0.0F);
		residualErrors = std::vector<floatT>(len, 0.0F);
		tempValues = std::vector<uint64_t>(len, 0L);
	}

	// Zero the temp vector
	std::fill(tempValues.begin(), tempValues.end(), 0L);
}

void LinearColorSmoothing::writeDirect()
{
	const int64_t now = micros();
	_previousValues = _targetValues;
	_previousWriteTime = now;

	queueColors(_previousValues);
}


void LinearColorSmoothing::writeFrame()
{
	const int64_t now = micros();
	_previousWriteTime = now;
	queueColors(_previousValues);
}


ALWAYS_INLINE int64_t LinearColorSmoothing::micros()
{
	const auto now = std::chrono::high_resolution_clock::now();
	return (std::chrono::duration_cast<std::chrono::microseconds>(now.time_since_epoch())).count();
}

void LinearColorSmoothing::assembleAndDitherFrame()
{
	if (meanValues.empty())
	{
		return;
	}

	// The number of LEDs present in each frame
	const size_t N = _targetValues.size();

	for (size_t i = 0; i < N; ++i)
	{
		// Add residuals for error diffusion (temporal dithering)
		const floatT fr = meanValues[3 * i + 0] + residualErrors[3 * i + 0];
		const floatT fg = meanValues[3 * i + 1] + residualErrors[3 * i + 1];
		const floatT fb = meanValues[3 * i + 2] + residualErrors[3 * i + 2];

		// Convert to to 8-bit value
		const long ir = clampRounded(fr);
		const long ig = clampRounded(fg);
		const long ib = clampRounded(fb);

		// Update the colors
		ColorRgb &prev = _previousValues[i];
		prev.red = static_cast<uint8_t>(ir);
		prev.green = static_cast<uint8_t>(ig);
		prev.blue = static_cast<uint8_t>(ib);

		// Determine the component errors
		residualErrors[3 * i + 0] = fr - ir;
		residualErrors[3 * i + 1] = fg - ig;
		residualErrors[3 * i + 2] = fb - ib;
	}
}

void LinearColorSmoothing::assembleFrame()
{
	if (meanValues.empty())
	{
		return;
	}

	// The number of LEDs present in each frame
	const size_t N = _targetValues.size();

	for (size_t i = 0; i < N; ++i)
	{
		// Convert to to 8-bit value
		const long ir = clampRounded(meanValues[3 * i + 0]);
		const long ig = clampRounded(meanValues[3 * i + 1]);
		const long ib = clampRounded(meanValues[3 * i + 2]);

		// Update the colors
		ColorRgb &prev = _previousValues[i];
		prev.red = static_cast<uint8_t>(ir);
		prev.green = static_cast<uint8_t>(ig);
		prev.blue = static_cast<uint8_t>(ib);
	}
}

ALWAYS_INLINE void LinearColorSmoothing::aggregateComponents(const std::vector<ColorRgb>& colors, std::vector<uint64_t>& weighted, const floatT weight) {
	// Determine the integer-scale by converting the weight to fixed point
	const uint64_t scale = (static_cast<uint64_t>(1L)<<FPShift) * static_cast<double>(weight);

	const size_t N = colors.size();

	for (size_t i = 0; i < N; ++i)
	{
		const ColorRgb &color = colors[i];

		// Scale the colors
		const uint64_t red = scale * color.red;
		const uint64_t green = scale * color.green;
		const uint64_t blue = scale * color.blue;

		// Accumulate in the vector
		weighted[3 * i + 0] += red;
		weighted[3 * i + 1] += green;
		weighted[3 * i + 2] += blue;
	}
}

void LinearColorSmoothing::interpolateFrame()
{
	const int64_t now = micros();

	// The number of leds present in each frame
	const size_t N = _targetValues.size();

	intitializeComponentVectors(N);

	/// Time where the frame has been shown
	int64_t frameStart;

	/// Time where the frame display would have ended
	int64_t frameEnd = now;

	/// Time where the current window has started
	const int64_t windowStart = now - (MS_PER_MICRO * _settlingTime);

	/// The total weight of the frames that were included in our window; sum of the individual weights
	floatT fs = 0.0F;

	// To calculate the mean component we iterate over all relevant frames;
	// from the most recent to the oldest frame that still clips our moving-average window given by time (now)
	for (auto it = _frameQueue.rbegin(); it != _frameQueue.rend() && frameEnd > windowStart; ++it)
	{
		// Starting time of a frame in the window is clipped to the window start
		frameStart = std::max(windowStart, it->time);

		// Weight the current frame relative to the overall window based on start and end times
		const floatT weight = _weightFrame(frameStart, frameEnd, windowStart);
		fs += weight;

		// Aggregate the RGB components of this frame's LED colors using the individual weighting
		aggregateComponents(it->colors, tempValues, weight);

		// The previous (earlier) frame display has ended when the current frame stared to show,
		// so we can use this as the frame-end time for next iteration
		frameEnd = frameStart;
	}

	/// The inverse scaling factor for the color components, clamped to (0, 1.0]; 1.0 for fs < 1, 1 : fs otherwise
	const floatT inv_fs = ((fs < 1.0F) ? 1.0F : 1.0F / fs) / (1 << SmallShiftBis);

	// Normalize the mean component values for the window (fs)
	for (size_t i = 0; i < 3 * N; ++i)
	{
		meanValues[i] = (tempValues[i] >> FPShiftSmall) * inv_fs;
	}

	_previousInterpolationTime = now;
}

void LinearColorSmoothing::performDecay(const int64_t now) {
	/// The target time when next frame interpolation should be performed
	const int64_t interpolationTarget = _previousInterpolationTime + _interpolationIntervalMicros;

	/// The target time when next write operation should be performed
	const int64_t writeTarget = _previousWriteTime + _outputIntervalMicros;

	/// Whether a frame interpolation is pending
	const bool interpolatePending = now > interpolationTarget;

	/// Whether a write is pending
	const bool writePending = now > writeTarget;

	// Check whether a new interpolation frame is due
	if (interpolatePending)
	{
		interpolateFrame();
		++_interpolationCounter;

		// Assemble the frame now when no dithering is applied
		if(!_dithering) {
			assembleFrame();
		}
	}

	// Check whether to frame output is due
	if (writePending)
	{
		// Dither the frame to diffuse rounding errors
		if(_dithering) {
			assembleAndDitherFrame();
		}

		writeFrame();
		++_renderedCounter;
	}

	// Check for sleep when no operation is pending.
	// As our QTimer is not capable of sub 1ms timing but instead performs spinning -
	// we have to do µsec-sleep to free CPU time; otherwise the thread would consume 100% CPU time.
	if(_updateInterval <= 0 && !(interpolatePending || writePending)) {
		const int64_t nextActionExpected = std::min(interpolationTarget, writeTarget);
		const int64_t microsTillNextAction = nextActionExpected - now;
		const int64_t SLEEP_MAX_MICROS = 1000L; // We want to use usleep for up to 1ms
		const int64_t SLEEP_RES_MICROS = 100L; // Expected resolution is >= 100µs on stock linux

		if(microsTillNextAction > SLEEP_RES_MICROS) {
			const int64_t wait = std::min(microsTillNextAction - SLEEP_RES_MICROS, SLEEP_MAX_MICROS);
			std::this_thread::sleep_for(std::chrono::microseconds(wait));
		}
	}

	// Write stats every 30 sec
	if ((now > (_renderedStatTime + 30 * 1000000)) && (_renderedCounter > _renderedStatCounter))
	{
		Debug(_log, "decay - rendered frames [%d] (%f/s), interpolated frames [%d] (%f/s) in [%f ms]"
			   , _renderedCounter - _renderedStatCounter
			   , (1.0F * (_renderedCounter - _renderedStatCounter) / ((now - _renderedStatTime) / 1000000.0F))
			   , _interpolationCounter - _interpolationStatCounter
			   , (1.0F * (_interpolationCounter - _interpolationStatCounter) / ((now - _renderedStatTime) / 1000000.0F))
			   , (now - _renderedStatTime) / 1000.0F
			   );
		_renderedStatTime = now;
		_renderedStatCounter = _renderedCounter;
		_interpolationStatCounter = _interpolationCounter;
	}
}

void LinearColorSmoothing::performLinear(const int64_t now) {
	const int64_t deltaTime = _targetTime - now;
	const float k = 1.0F - 1.0F * deltaTime / (_targetTime - _previousWriteTime);
	const size_t N = _previousValues.size();

	for (size_t i = 0; i < N; ++i)
	{
		const ColorRgb &target = _targetValues[i];
		ColorRgb &prev         = _previousValues[i];

		const int reddif   = target.red   - prev.red;
		const int greendif = target.green - prev.green;
		const int bluedif  = target.blue  - prev.blue;

		prev.red   += (reddif   < 0 ? -1:1) * std::ceil(k * std::abs(reddif));
		prev.green += (greendif < 0 ? -1:1) * std::ceil(k * std::abs(greendif));
		prev.blue  += (bluedif  < 0 ? -1:1) * std::ceil(k * std::abs(bluedif));
	}

	writeFrame();
}

void LinearColorSmoothing::updateLeds()
{
	const int64_t now = micros();
	const int64_t deltaTime = _targetTime - now;

	if (deltaTime < 0)
	{
		writeDirect();
		return;
	}

	switch (_smoothingType)
	{
	case SmoothingType::Decay:
		performDecay(now);
		break;

	case SmoothingType::Linear:
	default:
		performLinear(now);
		break;
	}
}

void LinearColorSmoothing::rememberFrame(const std::vector<ColorRgb> &ledColors)
{
	const int64_t now = micros();

	// Maintain the queue by removing outdated frames
	const int64_t windowStart = now - (MS_PER_MICRO * _settlingTime);

	int p = -1; // Start with -1 instead of 0, so we keep the last frame at least partially clipping the window

	// As the frames are ordered chronologically we scan from the front (oldest) till we find the first fresh frame
	for (auto it = _frameQueue.begin(); it != _frameQueue.end() && it->time < windowStart; ++it)
	{
		++p;
	}

	if (p > 0)
	{
		_frameQueue.erase(_frameQueue.begin(), _frameQueue.begin() + p);
	}

	// Append the latest frame at back of the queue
	const REMEMBERED_FRAME frame = REMEMBERED_FRAME(now, ledColors);
	_frameQueue.push_back(frame);
}


void LinearColorSmoothing::clearRememberedFrames()
{
	_frameQueue.clear();

	_ledCount = 0;
	meanValues.clear();
	residualErrors.clear();
	tempValues.clear();
}

void LinearColorSmoothing::queueColors(const std::vector<ColorRgb> &ledColors)
{
	assert (ledColors.size() > 0);

	if (_outputDelay == 0)
	{
		// No output delay => immediate write
		if (!_pause)
		{
			emit _hyperion->ledDeviceData(ledColors);
		}
	}
	else
	{
		// Push new colors in the delay-buffer
		_outputQueue.push_back(ledColors);

		// If the delay-buffer is filled pop the front and write to device
		if (!_outputQueue.empty())
		{
			if (_outputQueue.size() > _outputDelay)
			{
				if (!_pause)
				{
					emit _hyperion->ledDeviceData(_outputQueue.front());
				}
				_outputQueue.pop_front();
			}
		}
	}
}

void LinearColorSmoothing::clearQueuedColors()
{
	_timer->stop();
	_previousValues.clear();

	_targetValues.clear();

	clearRememberedFrames();
}

void LinearColorSmoothing::componentStateChange(hyperion::Components component, bool state)
{
	if (component == hyperion::COMP_SMOOTHING)
	{
		setEnable(state);
	}
}

void LinearColorSmoothing::setEnable(bool enable)
{
	if ( _enabled != enable)
	{
		_enabled = enable;
		if (!_enabled)
		{
			clearQueuedColors();
		}
		// update comp register
		_hyperion->setNewComponentState(hyperion::COMP_SMOOTHING, enable);
	}
}

void LinearColorSmoothing::setPause(bool pause)
{
	_pause = pause;
}

unsigned LinearColorSmoothing::addConfig(int settlingTime_ms, double ledUpdateFrequency_hz, unsigned updateDelay)
{
	SmoothingCfg cfg {
		false,
		settlingTime_ms,
		static_cast<int>(MS_PER_MICRO / ledUpdateFrequency_hz),
		SmoothingType::Linear,
		ledUpdateFrequency_hz,
		updateDelay
	};
	_cfgList.append(cfg);

	DebugIf(verbose && _enabled, _log,"%s", QSTRING_CSTR(getConfig(_cfgList.count()-1)));

	return _cfgList.count() - 1;
}

unsigned LinearColorSmoothing::updateConfig(int cfgID, int settlingTime_ms, double ledUpdateFrequency_hz, unsigned updateDelay)
{
	int updatedCfgID = cfgID;
	if (cfgID < _cfgList.count())
	{
		SmoothingCfg cfg {
			false,
			settlingTime_ms,
			static_cast<int>(MS_PER_MICRO / ledUpdateFrequency_hz),
			SmoothingType::Linear,
			ledUpdateFrequency_hz,
			updateDelay
		};
		_cfgList[updatedCfgID] = cfg;
		Debug(_log,"%s", QSTRING_CSTR(getConfig(updatedCfgID)));
	}
	else
	{
		updatedCfgID = addConfig(settlingTime_ms, ledUpdateFrequency_hz, updateDelay);
	}
	return updatedCfgID;
}

bool LinearColorSmoothing::selectConfig(int cfgID, bool force)
{
	if (_currentConfigId == cfgID && !force)
	{
		return true;
	}

	if (cfgID < _cfgList.count() )
	{
		_smoothingType = _cfgList[cfgID]._type;
		_settlingTime = _cfgList[cfgID]._settlingTime;
		_outputDelay = _cfgList[cfgID]._outputDelay;
		_pause = _cfgList[cfgID]._pause;
		_outputIntervalMicros = int64_t(1000000.0 / _updateInterval); // 1s = 1e6 µs
		_interpolationRate = _cfgList[cfgID]._interpolationRate;
		_interpolationIntervalMicros = int64_t(1000000.0 / _interpolationRate);
		_dithering = _cfgList[cfgID]._dithering;
		_decay = _cfgList[cfgID]._decay;
		_invWindow = 1.0F / (MS_PER_MICRO * _settlingTime);

		// Set _weightFrame based on the given decay
		const float decay = _decay;
		const floatT inv_window = _invWindow;

		// For decay != 1 use power-based approach for calculating the moving average values
		if(std::abs(decay - 1.0F) > std::numeric_limits<float>::epsilon()) {
			// Exponential Decay
			_weightFrame = [inv_window,decay](const int64_t fs, const int64_t fe, const int64_t ws) {
				const floatT s = (fs - ws) * inv_window;
				const floatT t = (fe - ws) * inv_window;

				return (decay + 1) * (std::pow(t, decay) - std::pow(s, decay));
			};
		} else {
			// For decay == 1 use linear interpolation of the moving average values
			// Linear Decay
			_weightFrame = [inv_window](const int64_t fs, const int64_t fe, const int64_t /*ws*/) {
				// Linear weighting = (end - start) * scale
				return static_cast<floatT>((fe - fs) * inv_window);
			};
		}

		_renderedStatTime = micros();
		_renderedCounter = 0;
		_renderedStatCounter = 0;
		_interpolationCounter = 0;
		_interpolationStatCounter = 0;

		//Enable smoothing for effects with smoothing
		if (cfgID >= SmoothingConfigID::EFFECT_DYNAMIC)
		{
			Debug(_log,"Run Effect with Smoothing enabled");
			_enabledSystemCfg = _enabled;
			setEnable(true);
		}
		else
		{
			// Restore enabled state after running an effect with smoothing
			setEnable(_enabledSystemCfg);
		}

		if (_cfgList[cfgID]._updateInterval != _updateInterval)
		{

			_timer->stop();
			_updateInterval = _cfgList[cfgID]._updateInterval;
			if (this->enabled())
			{
				if (!_pause && !_targetValues.empty())
				{
					_timer->start(_updateInterval);
				}
			}
		}
		_currentConfigId = cfgID;
		DebugIf(_enabled, _log,"%s", QSTRING_CSTR(getConfig(_currentConfigId)));

		return true;
	}

	// reset to default
	_currentConfigId = SmoothingConfigID::SYSTEM;
	return false;
}

QString LinearColorSmoothing::getConfig(int cfgID)
{
	QString configText;

	if (cfgID < _cfgList.count())
	{
		SmoothingCfg cfg = _cfgList[cfgID];

		configText = QString ("[%1] - Type: %2, Pause: %3")
					 .arg(cfgID)
					 .arg(SmoothingCfg::EnumToString(cfg._type),(cfg._pause) ? "true" : "false") ;

		switch (cfg._type) {
		case SmoothingType::Decay:
		{
			const double thalf = (1.0-std::pow(1.0/2, 1.0/_decay))*_settlingTime;
			configText += QString (", Interpolation rate: %1Hz, Dithering: %2, decay: %3 -> Halftime: %4ms")
						  .arg(cfg._interpolationRate,0,'f',2)
						  .arg((cfg._dithering) ? "true" : "false")
						  .arg(cfg._decay,0,'f',2)
						  .arg(thalf,0,'f',2);
			[[fallthrough]];
		}

		case SmoothingType::Linear:
		{
			configText += QString (", Settling time: %1ms, Interval: %2ms (%3Hz)")
						  .arg(cfg._settlingTime)
						  .arg(cfg._updateInterval)
						  .arg(int(MS_PER_MICRO/cfg._updateInterval));
			break;
		}
		}

		configText += QString (", delay: %1 frames")
					  .arg(cfg._outputDelay);
	}

	return configText;
}

LinearColorSmoothing::SmoothingCfg::SmoothingCfg() :
	  _pause(false),
	  _settlingTime(DEFAULT_SETTLINGTIME),
	  _updateInterval(DEFAULT_UPDATEFREQUENCY),
	  _type(SmoothingType::Linear)
{
}

LinearColorSmoothing::SmoothingCfg::SmoothingCfg(bool pause, int64_t settlingTime, int updateInterval, SmoothingType type, double interpolationRate, unsigned outputDelay, bool dithering, double decay) :
	  _pause(pause),
	  _settlingTime(settlingTime),
	  _updateInterval(updateInterval),
	  _type(type),
	  _interpolationRate(interpolationRate),
	  _outputDelay(outputDelay),
	  _dithering(dithering),
	  _decay(decay)
{
}

QString LinearColorSmoothing::SmoothingCfg::EnumToString(SmoothingType type)
{
	if (type == SmoothingType::Linear) {
		return QString("Linear");
	}

	if (type == SmoothingType::Decay)
	{
		return QString("Decay");
	}

	return QString("Unknown");
}