protected override float PerPixelOperation(Matrix input, int row, int column)
{
float signalMean;
float signalVariance;
float trimmedMean;
//calculate signal mean 1 and signal variance 1
SignalMeanInfo signalMeanInfo = new SignalMeanInfo();
DoWindowPass(input, row, column, CalculateSignalMean, signalMeanInfo);
signalMean = signalMeanInfo.sum / signalMeanInfo.count;
SignalVarianceInfo signalVarianceInfo = new SignalVarianceInfo();
signalVarianceInfo.signalMean = signalMean;
DoWindowPass(input, row, column, CalculateSignalVariance, signalVarianceInfo);
signalVariance = signalVarianceInfo.sum / (signalVarianceInfo.count - 1);
//calculate z and eta and trimmed mean
ZtmInfo ztmInfo = new ZtmInfo(WindowSize);
ztmInfo.mean = signalMean;
ztmInfo.stdev = (float)Math.Sqrt(signalVariance);
DoWindowPass(input, row, column, CalcTrimmedMean, ztmInfo);
trimmedMean = ztmInfo.sum / ztmInfo.eta;
return(trimmedMean);
}
protected virtual void CalcTrimmedMean(float value, int row, int column, int rowWithinWindow, int columnWithinWindow, ZtmInfo info)
{
float z = Math.Abs((value - info.mean) / info.stdev);
info.z[rowWithinWindow, columnWithinWindow] = z;
if (z <= _zeta)
{
info.eta++;
info.sum += value;
}
}