/// <summary>
/// Calculate SCR features.
/// </summary>
///
/// <param name="timeWindow">The time window.</param>
/// <param name="timeScale">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 GetArousalStatistics(double timeWindow, TimeWindowMeasure timeScale)
{
signalValues = GetSignalValues();
//The signal values receved by device are already filtered (we give the average of eight sequence values).
//Therefore it is not needed to apply other filter.
SignalDataByTime[] medianFilterCoordinates = GetMedianFilterPoints(signalValues);
if (medianFilterCoordinates != null)
{
return(GetArousalStatisticsByMedianFilter(medianFilterCoordinates, timeWindow, timeScale));
}
return(GetArousalStatisticsByMedianFilter(signalValues, timeWindow, timeScale));;
}
/// <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 number of affected signal values depending on time window.
/// </summary>
///
/// <param name="coordinates">List of all signal values stored in the cache.</param>
/// <param name="timeWindow">Time wondow.</param>
/// <param name="sampleRate">Sample rate.</param>
///
/// <returns>
/// Number of affected signal values.
/// </returns>
private int GetNumberOfAffectedPoints(List <SignalDataByTime> coordinates, double timeWindow, TimeWindowMeasure timewindowType, int sampleRate)
{
timeWindow = timewindowType.Equals(TimeWindowMeasure.Milliseconds) ? (timeWindow / 1000) : timeWindow;
int numberOfAffectedPoints = Convert.ToInt32((1000.0 / sampleRate) * timeWindow, CultureInfo.InvariantCulture);
double minAcceptableTime = timeWhenSignalValuesAreExtracted - timeWindow * 1000;
if (coordinates.Count < numberOfAffectedPoints)
{
return(coordinates.Count);
}
for (int i = (coordinates.Count - numberOfAffectedPoints - 1); i < coordinates.Count; i++)
{
if (coordinates[i].Time < minAcceptableTime)
{
numberOfAffectedPoints--;
}
else
{
break;
}
}
if ((coordinates.Count - numberOfAffectedPoints) > 1)
{
for (int i = (coordinates.Count - numberOfAffectedPoints - 2); i > -1; i--)
{
if (coordinates[i].Time >= minAcceptableTime)
{
numberOfAffectedPoints++;
}
else
{
break;
}
}
}
return(numberOfAffectedPoints);
}
/// <summary>
/// Calculate arousal statistics for the passed time window in seconds.
/// </summary>
///
/// <param name="timeWindowType">The type of time window: milliseconds or seconds.</param>
/// <param name="timeWindow">Time wondow.</param>
///
/// <returns>
/// Arousal statistics for the passed time window in seconds.
/// </returns>
public ArousalStatistics GetArousalStatistics(List <SignalDataByTime> highPassCoordinates, double timeWindow, TimeWindowMeasure timeWindowType, int sampleRate)
{
if (timeWindow.CompareTo(0) <= 0 || sampleRate <= 0 || highPassCoordinates.Count <= 0)
{
return(null);
}
int numberOfAffectedPoints = GetNumberOfAffectedPoints(highPassCoordinates, timeWindow, timeWindowType, sampleRate);
//if (coordinates.Count < numberOfAffectedPoints) return GetArousalInfoForCoordinates(coordinates, coordinates.Count, defaultTimeWindow);
double timeWindowInSeconds = timeWindowType.Equals(TimeWindowMeasure.Milliseconds) ? timeWindow / 1000 : timeWindow;
return(GetArousalInfoForCoordinates(highPassCoordinates, numberOfAffectedPoints, timeWindowInSeconds));
}
