/// <summary>
/// Compares one signature to all signatures of a template
/// </summary>
/// <param name="aTemplate"></param>
/// <param name="aSignature"></param>
/// <param name="aDTWConfig"></param>
/// <returns></returns>
public static double CompareSignatureDTW(List <Signature> aTemplate, Signature aSignature, DTWConfiguration aDTWConfig)
{
int lCounter = 0;
double lScore = 0;
foreach (Signature refSig in aTemplate)
{
lScore += ConfigurableDTW.DTWDistance(refSig, aSignature, aDTWConfig);
++lCounter;
}
lScore /= lCounter;
return(lScore);
}
/// <summary>
/// Removes the worst aNrOfSamplesToRemove samples from the template
/// </summary>
/// <param name="aDirectory"></param>
/// <param name="aNrOfSamplesToRemove"></param>
/// <param name="aDTWConfig"></param>
/// <param name="aTolerance"></param>
public static void RemoveWorstSamples(string aDirectory, int aNrOfSamplesToRemove, DTWConfiguration aDTWConfig, double aTolerance = 0.05)
{
List <Signature> lSignaturesOfUser = SignatureFileUtils.GetAllSignaturesFromFolder(aDirectory, true);
List <double> lListOfAverageOfScores = new List <double>();
List <List <double> > lListOfScores = new List <List <double> >();
//Compare all signatures to the rest, one by one and save the scores in a matrix
for (int i = 0; i < lSignaturesOfUser.Count; ++i)
{
var lSigToCompare = lSignaturesOfUser.ElementAt(i);
List <double> lResults = new List <double>();
for (int j = 0; j < lSignaturesOfUser.Count; ++j)
{
var lSig = lSignaturesOfUser.ElementAt(j);
lResults.Add(ConfigurableDTW.DTWDistance(lSigToCompare, lSig, aDTWConfig));
}
lListOfScores.Add(lResults);
}
//Calculate the average of the scores
for (int i = 0; i < lListOfScores.Count; ++i)
{
for (int j = 0; j < lListOfScores.ElementAt(i).Count; ++i)
{
if (i == 0)
{
lListOfAverageOfScores.Add(lListOfScores[i][j]);
}
else
{
lListOfAverageOfScores[j] += lListOfScores[i][j];
}
}
}
for (int i = 0; i < lListOfAverageOfScores.Count; ++i)
{
lListOfAverageOfScores[i] /= lListOfAverageOfScores.Count;
}
//Remove the worst samples
for (int i = 0; i < aNrOfSamplesToRemove; ++i)
{
//delete the signature files from disk
var lIndexToRemove = lListOfAverageOfScores.IndexOf(lListOfAverageOfScores.Max());
File.Delete(lSignaturesOfUser.ElementAt(lIndexToRemove).Filename);
}
}
/// <summary>
/// Compares each element of the aSignatures parameter to each element of aTemplate.
/// One signature gets compared to all elements of the template, then an average will be calcutated
/// </summary>
/// <param name="aTemplate"></param>
/// <param name="aSignatures"></param>
/// <param name="aDTWConfig"></param>
public static List <double> CompareSignaturesDTW(List <Signature> aTemplate, List <Signature> aSignatures, DTWConfiguration aDTWConfig)
{
List <double> lScores = new List <double>();
foreach (Signature sig in aSignatures)
{
int lCounter = 0;
double lScore = 0;
foreach (Signature refSig in aTemplate)
{
lScore += ConfigurableDTW.DTWDistance(refSig, sig, aDTWConfig);
++lCounter;
}
lScore /= lCounter;
lScores.Add(lScore);
}
return(lScores);
}
/// <summary>
/// Checks the quality of the signature
/// Can be used at taking samples, ot at validating a signature
/// </summary>
/// <param name="aDirectory"></param>
/// <param name="aSignature"></param>
/// <returns></returns>
public static bool CheckQuality(string aDirectory, Signature aSignature, DTWConfiguration aDTWConfig, double aTolerance = 0.05)
{
int lNumberOfRegisteredSamples = SignatureFileUtils.GetNumberOfSignaturesFromFolder(aDirectory);
if (lNumberOfRegisteredSamples > 1)
{
List <Signature> lSignaturesOfUser = SignatureFileUtils.GetAllSignaturesFromFolder(aDirectory, true);
List <double> lListOfScores = new List <double>();
//Take the first element from the registered samples
Signature lSignatureToCompare = lSignaturesOfUser.ElementAt(0);
List <double> lListOfScoresRegisteredSig = new List <double>();
//Compare the first element of the registered signature to the rest of the template and save the scores
for (int i = 1; i < lSignaturesOfUser.Count; i++)
{
var lSig = lSignaturesOfUser.ElementAt(i);
lListOfScoresRegisteredSig.Add(ConfigurableDTW.DTWDistance(lSignatureToCompare, lSig, aDTWConfig));
}
//Compare the aSignature sample to the template and save the scores
foreach (Signature lSig in lSignaturesOfUser)
{
lListOfScores.Add(ConfigurableDTW.DTWDistance(aSignature, lSig, aDTWConfig));
}
//Compare the average of the two score lists, accept of reject the signature
if (lListOfScores.Average() > lListOfScoresRegisteredSig.Average() + aTolerance)
{
return(false);
}
else
{
return(true);
}
}
else
{
return(true);
}
}
public static bool Authenticate(string aDirectory, Signature aSignature, DTWConfiguration aDTWConfig, double aTolerance = 0.05)
{
List <Signature> lSignaturesOfUser = SignatureFileUtils.GetAllSignaturesFromFolder(aDirectory, true);
List <double> lListOfScores = new List <double>();
//Check for NAN in the signature sample
//If an attribute is NAN, but is checked for usage by the DTWConfig, uncheck it
SignatureUtils.CheckForNaN(lSignaturesOfUser.ElementAt(0), ref aDTWConfig);
//Take the first element from the registered samples
Signature lSignatureToCompare = lSignaturesOfUser.ElementAt(0);
List <double> lListOfScoresRegisteredSig = new List <double>();
//Compare the first element of the registered signature to the rest of the template and save the scores
for (int i = 1; i < lSignaturesOfUser.Count; i++)
{
var lSig = lSignaturesOfUser.ElementAt(i);
lListOfScoresRegisteredSig.Add(ConfigurableDTW.DTWDistance(lSignatureToCompare, lSig, aDTWConfig));
}
//Compare the aSignature sample to the template and save the scores
foreach (Signature lSig in lSignaturesOfUser)
{
lListOfScores.Add(ConfigurableDTW.DTWDistance(aSignature, lSig, aDTWConfig));
}
//Compare the average of the two score lists, accept of reject the signature
if (lListOfScores.Average() > lListOfScoresRegisteredSig.Average() + aTolerance)
{
return(false);
}
else
{
return(true);
}
}
