/// <summary>
/// Convert an ArousalStatistics object in JSON string.
/// </summary>
///
/// <param name="statisticObject">The target arousal statistics</param>
///
/// <returns>
/// The arousal statistic in JSON format.
/// </returns>
public string GetJSONArousalStatistics(ArousalStatistics statisticObject)
{
JavaScriptSerializer js = new JavaScriptSerializer();
string json = js.Serialize(statisticObject);
return(json);
}
/// <summary>
/// Calculate arousal statistics for the passed time window.
/// </summary>
///
/// <param name="highPassCoordinates">List of all signal values stored in the cache.</param>
/// <param name="numberOfAffectedPoints">Number of affected points.</param>
/// <param name="timeWindow">Time wondow.</param>
///
/// <returns>
/// Arousal statistics for the passed time window.
/// </returns>
private ArousalStatistics GetArousalInfoForCoordinates(List <SignalDataByTime> highPassCoordinates, int numberOfAffectedPoints, double timeWindow)
{
InflectionLine inflectionLinesHandler = new InflectionLine();
List <SignalDataByTime> highPassCoordinatesByTimeWindow = AffectedCoordinatePoints(highPassCoordinates, numberOfAffectedPoints);
List <InflectionPoint> inflectionPoints = inflectionLinesHandler.GetInflectionPoints(highPassCoordinatesByTimeWindow, "highPass");
ArousalStatistics result = new ArousalStatistics();
result = GetArousalInfoForInflectionPoints(inflectionPoints, timeWindow);
result.SCRArousalArea = GetArousalArea(highPassCoordinatesByTimeWindow, timeWindow);
result.MovingAverage = GetMovingAverage(signalValues, numberOfAffectedPoints);
result.GeneralArousalLevel = GetGeneralArousalLevel(result.MovingAverage);
result.SCRAchievedArousalLevel = GetPhasicLevel(result.SCRArousalArea);
result.LastValue = highPassCoordinates.ElementAt(highPassCoordinates.Count - 1).HighPassValue;
result.LastRawSignalValue = signalValues.ElementAt(signalValues.Length - 1).SignalValue;
return(result);
}
/// <summary>
/// Calculate SCR features after aplying median filter on the signal values.
/// </summary>
///
/// <param name="medianFilterCoordinates">List of new signal values after aplying median filter on raw signal values.</param>
/// <param name="timeWindow">The time window.</param>
/// <param name="timeMeasure">The time scale - it can be in milliseconds or in seconds.</param>
///
/// <returns>
/// The arousal statistic according to the specified time window.
/// </returns>
public ArousalStatistics GetArousalStatisticsByMedianFilter(SignalDataByTime[] medianFilterCoordinates, double timeWindow, TimeWindowMeasure timeMeasure)
{
if (timeWindow.CompareTo(0.0) <= 0)
{
timeWindow = defaultTimeWindow;
timeMeasure = TimeWindowMeasure.Seconds;
}
ArousalStatistics butterworthStatistics = GetArousalStatistics(medianFilterCoordinates.ToList(), timeWindow, timeMeasure, sampleRate);
if (butterworthStatistics != null)
{
butterworthStatistics.TonicStatistics = GetTonicStatistics(medianFilterCoordinates.ToList());
butterworthStatistics.SCLAchievedArousalLevel = GetTonicLevel(butterworthStatistics.TonicStatistics.MeanAmp);
butterworthStatistics.LowPassSignalValue = medianFilterCoordinates[medianFilterCoordinates.Count() - 1].LowPassValue;
butterworthStatistics.HighPassSignalValue = medianFilterCoordinates[medianFilterCoordinates.Count() - 1].HighPassValue;
butterworthStatistics.LastMedianFilterValue = medianFilterCoordinates[medianFilterCoordinates.Count() - 1].SignalValue;
}
return(butterworthStatistics);
}
/// <summary>
/// Calculate following arousal features:
/// - SCR Amplitude;
/// - SCR Rise
/// - SCR Recovery
/// </summary>
///
/// <param name="inflectionPoints"> List of inflection points. </param>
/// <param name="timeWindow"> Time window. </param>
///
/// <returns>
/// Arousal statistic with information for SCR Amplitude, SCR Rise, and SCR Recovery.
/// </returns>
public ArousalStatistics GetArousalInfoForInflectionPoints(List <InflectionPoint> inflectionPoints, double timeWindow)
{
InflectionLine inflectionLinesHandler = new InflectionLine();
ArousalStatistics arousalStat = new ArousalStatistics();
ArousalFeature scrAmplitude = new ArousalFeature("Amplitude");
ArousalFeature scrRise = new ArousalFeature("Rise time");
ArousalFeature scrRecovery = new ArousalFeature("Recovery time");
List <double> allMaximums = new List <double>();
List <double> allRises = new List <double>();
List <double> allRecoveryTimes = new List <double>();
double sumMaximums = 0;
double sumRises = 0;
double sumRecoveryTime = 0;
int indexPreviousMinimum = -1;
int indexNextMinimum = -1;
bool passInitialization = false;
bool passInitializationRice = false;
bool isRecoveryExist = false;
for (int i = 0; i < (inflectionPoints.Count); i++)
{
if (inflectionPoints.ElementAt(i).ExtremaType.Equals(ExtremaType.Minimum))
{
indexPreviousMinimum = i;
}
if (inflectionPoints.ElementAt(i).ExtremaType.Equals(ExtremaType.Maximum))
{
//for rise statistics we have to find previous min. current maximum and next minimum
double x0 = (indexPreviousMinimum > -1) ? inflectionPoints.ElementAt(indexPreviousMinimum).CoordinateX : inflectionPoints.ElementAt(0).CoordinateX;
double x1 = inflectionPoints.ElementAt(i).CoordinateX;
double y1 = inflectionPoints.ElementAt(i).CoordinateY;
//searching for the next minimum
for (int j = (i + 1); j < inflectionPoints.Count; j++)
{
if (inflectionPoints.ElementAt(j).ExtremaType.Equals(ExtremaType.Minimum))
{
indexNextMinimum = j;
indexPreviousMinimum = indexNextMinimum;
isRecoveryExist = true;
break;
}
}
double x2 = (isRecoveryExist) ? inflectionPoints.ElementAt(indexNextMinimum).CoordinateX : 0.0;
isRecoveryExist = isRecoveryExist && (x2 - x1).CompareTo(0.1) > 0;
double currentAmplitude = y1;
double currentRise = x1 - x0;
double currentRecouvery = (isRecoveryExist) ? (x2 - x1) / 2 : 0.0;
if (!passInitialization)
{
scrAmplitude.Maximum = currentAmplitude;
scrAmplitude.Minimum = currentAmplitude;
if (isRecoveryExist && currentRecouvery.CompareTo(0.0) > 0)
{
scrRecovery.Maximum = currentRecouvery;
scrRecovery.Minimum = currentRecouvery;
}
passInitialization = true;
}
else
{
scrAmplitude.Maximum = (scrAmplitude.Maximum.CompareTo(currentAmplitude) < 0) ? currentAmplitude : scrAmplitude.Maximum;
scrAmplitude.Minimum = (scrAmplitude.Minimum.CompareTo(currentAmplitude) > 0 && currentAmplitude.CompareTo(0.0) != 0) ? currentAmplitude : scrAmplitude.Minimum;
if (isRecoveryExist && currentRecouvery.CompareTo(0.0) > 0)
{
scrRecovery.Maximum = (scrRecovery.Maximum.CompareTo(currentRecouvery) < 0) ? currentRecouvery : scrRecovery.Maximum;
scrRecovery.Minimum = (scrRecovery.Minimum.CompareTo(currentRecouvery) > 0) ? currentRecouvery : scrRecovery.Minimum;
}
}
if (i > 0 && !passInitializationRice && (currentRise.CompareTo(0.1) > 0))
{
scrRise.Maximum = currentRise;
scrRise.Minimum = currentRise;
passInitializationRice = true;
}
else if (i > 0 && passInitializationRice && (currentRise.CompareTo(0.1) > 0))
{
scrRise.Maximum = (scrRise.Maximum.CompareTo(currentRise) < 0) ? currentRise : scrRise.Maximum;
scrRise.Minimum = (scrRise.Minimum.CompareTo(currentRise) > 0) ? currentRise : scrRise.Minimum;
}
if (isRecoveryExist && currentRecouvery.CompareTo(0.0) > 0)
{
allRecoveryTimes.Add(currentRecouvery);
sumRecoveryTime += currentRecouvery;
}
allMaximums.Add(currentAmplitude);
sumMaximums += currentAmplitude;
if ((i > 0) && (currentRise.CompareTo(0.1) > 0))
{
allRises.Add(currentRise);
sumRises += currentRise;
}
if (isRecoveryExist)
{
i = indexNextMinimum;
}
}
isRecoveryExist = false;
}
scrAmplitude.Mean = (allMaximums != null && allMaximums.Count > 0) ? Convert.ToDecimal(sumMaximums / allMaximums.Count, CultureInfo.InvariantCulture) : 0;
scrAmplitude.Count = allMaximums.Count / timeWindow;
scrAmplitude.StdDeviation = GetStandardDeviation(allMaximums, scrAmplitude.Mean);
arousalStat.SCRAmplitude = scrAmplitude;
scrRise.Mean = (allRises != null && allRises.Count > 0) ? Convert.ToDecimal(sumRises / allRises.Count, CultureInfo.InvariantCulture) : 0;
scrRise.Count = allRises.Count / timeWindow;
scrRise.StdDeviation = GetStandardDeviation(allRises, scrRise.Mean);
arousalStat.SCRRise = scrRise;
scrRecovery.Mean = (allRecoveryTimes != null && allRecoveryTimes.Count > 0) ? Convert.ToDecimal(sumRecoveryTime / allRecoveryTimes.Count, CultureInfo.InvariantCulture) : 0;
scrRecovery.Count = allRecoveryTimes.Count / timeWindow;
scrRecovery.StdDeviation = GetStandardDeviation(allRecoveryTimes, scrRecovery.Mean);
arousalStat.SCRRecoveryTime = scrRecovery;
return(arousalStat);
}