/*
* Created by: Miguel Angel Medina P�rez (miguel.medina.perez@gmail.com)
* Created: Thursday, December 21, 2007
* Comments by: Miguel Angel Medina P�rez (miguel.medina.perez@gmail.com)
*/
using System;
namespace PatternRecognition.FingerprintRecognition.Core
{
/// <summary>
/// Represents the type of the minutia.
/// </summary>
public enum MinutiaType
{
/// <summary>
/// Represents a minutia which type could not be identified.
/// </summary>
Unknown,
/// <summary>
/// Represents a ridge ending.
/// </summary>
End,
/// <summary>
/// Represents a ridge bifurcation.
/// </summary>
Bifurcation,
} ;
/// <summary>
/// Represents a minutia.
/// </summary>
/// <remarks>
/// <para>
/// This minutia representation assumes that the angle is represented in radians.
/// </para>
/// <para>
/// The hash code of these objects uses four bytes per minutia: <see cref="Minutia.X"/> in the left most 11 bits; <see cref="Minutia.Y"/> in the next 11 bits; <see cref="Minutia.Angle"/> in the next eight bits; and <see cref="Minutia.MinutiaType"/> in the last two bits. Therefore, this method is ineffective for values of <see cref="Minutia.X"/> or <see cref="Minutia.Y"/> greater than 2047.
/// </para>
/// </remarks>
[Serializable]
public class Minutia
{
/// <summary>
/// Initializes a new instance of the <see cref="Minutia"/> class using the specified location and angle.
/// </summary>
/// <remarks>
/// The default value of <see cref="MinutiaType"/> is <see cref="Core.MinutiaType.Unknown"/>.
/// </remarks>
/// <param name="x">
/// The horizontal position of the minutia.
/// </param>
/// <param name="y">
/// The vertical position of the minutia.
/// </param>
/// <param name="angle">
/// The angle of the minutia.
/// </param>
public Minutia(Int16 x, Int16 y, double angle)
{
X = x;
Y = y;
Angle = angle;
MinutiaType = MinutiaType.Unknown;
Flag = false;
}
public Minutia()
{
X = 0;
Y = 0;
Angle = 0;
MinutiaType = MinutiaType.Unknown;
Flag = false;
}
/// <summary>
/// Returns a hash code for the current minutia.
/// </summary>
/// <remarks>
/// When building hash code, this method stores value X in the left most 11 bits; value Y, in the next 11 bits; value Angle, in the next 8 bits; and value MinutiaType, in the last 2 bits. Therefore, this method could be ineffective for values of X or Y greater than 2047.
/// </remarks>
/// <returns>
/// A hash code for the current minutia.
/// </returns>
public override int GetHashCode()
{
// Storing value X in the left most 11 bits.
int blockX = (2047 & X) << 21;
// Storing value Y in the next 11 bits.
int blockY = (2047 & Y) << 10;
// Storing value Angle in the next 8 bits.
int blockAngle = Convert.ToByte(Math.Round(Angle * 255 / (2 * Math.PI))) << 2;
// Storing value MinutiaType in the last 2 bits.
int blockType = MinutiaType == MinutiaType.Unknown ? 0 : (MinutiaType == MinutiaType.End ? 1 : 2);
return blockX | blockY | blockAngle | blockType;
}
/// <summary>
/// Determines whether two specified minutiae have the same property values.
/// </summary>
/// <param name="m1">A minutia.</param>
/// <param name="m2">A minutia.</param>
/// <returns>
/// True if every property value of <paramref name="m1"/> is equal to the respective property value of <paramref name="m2"/>; otherwise, false.
/// </returns>
public static bool operator ==(Minutia m1, Minutia m2)
{
return m1.X == m2.X && m1.Y == m2.Y && m1.Angle == m2.Angle;
}
/// <summary>
/// Determines whether two specified minutiae have different property values.
/// </summary>
/// <param name="m1">A minutia.</param>
/// <param name="m2">A minutia.</param>
/// <returns>
/// True if every property value of <paramref name="m1"/> is different from the respective property value of <paramref name="m2"/>; otherwise, false.
/// </returns>
public static bool operator !=(Minutia m1, Minutia m2)
{
return !Equals(m1, m2);
}
/// <summary>
/// Gets or sets the horizontal position of the minutia.
/// </summary>
public Int16 X { set; get; }
/// <summary>
/// Gets or sets the vertical position of the minutia.
/// </summary>
public Int16 Y { set; get; }
/// <summary>
/// Gets or sets the angle of the minutia in radians.
/// </summary>
public double Angle { set; get; }
/// <summary>
/// Gets or sets the minutia type.
/// </summary>
public MinutiaType MinutiaType { set; get; }
/// <summary>
/// Allows flagging the minutia;
/// </summary>
public bool Flag { set; get; }
}
/// <summary>
/// Utility class used to store two minutiae and its matching value.
/// </summary>
public class MinutiaPair
{
/// <summary>
/// Gets or sets a minutia from the query fingerprint.
/// </summary>
public Minutia QueryMtia { set; get; }
/// <summary>
/// Gets or sets a minutia from the template fingerprint.
/// </summary>
public Minutia TemplateMtia { set; get; }
/// <summary>
/// Gets or sets the matching value of the two minutiae.
/// </summary>
public double MatchingValue { set; get; }
/// <summary>
/// Returns a hash code for the current <see cref="MinutiaPair"/>.
/// </summary>
/// <returns></returns>
public override int GetHashCode()
{
unchecked
{
return (QueryMtia.GetHashCode() * 397) ^ TemplateMtia.GetHashCode();
}
}
public override string ToString()
{
return GetHashCode().ToString();
}
/// <summary>
/// Determines whether two specified pairs have the same minutiae.
/// </summary>
/// <param name="mp1">A minutia pair.</param>
/// <param name="mp2">A minutia pair.</param>
/// <returns>
/// True if the <see cref="QueryMtia"/> objects of the specified pairs have equal values and the <see cref="TemplateMtia"/> objects have equal values.
/// </returns>
public static bool operator ==(MinutiaPair mp1, MinutiaPair mp2)
{
if (!ReferenceEquals(null, mp1))
return mp1.Equals(mp2);
if (ReferenceEquals(null, mp1) && ReferenceEquals(null, mp2))
return true;
return false;
}
/// <summary>
/// Determines whether two specified pairs have different minutiae.
/// </summary>
/// <param name="mp1">A minutia pair.</param>
/// <param name="mp2">A minutia pair.</param>
/// <returns>
/// True if the <see cref="QueryMtia"/> objects of the specified pairs have different values or the <see cref="TemplateMtia"/> objects have different values.
/// </returns>
public static bool operator !=(MinutiaPair mp1, MinutiaPair mp2)
{
if (!ReferenceEquals(null, mp1))
return !mp1.Equals(mp2);
if (ReferenceEquals(null, mp1) && ReferenceEquals(null, mp2))
return false;
return true;
}
/// <summary>
/// Determines wheter the specified <see cref="MinutiaPair"/> and the current object have the same minutiae.
/// </summary>
/// <param name="obj">
/// The <see cref="MinutiaPair"/> to compare with the current object.
/// </param>
/// <returns>
/// True if the <see cref="QueryMtia"/> and <see cref="TemplateMtia"/> objects of the specified pair have the same values as the <see cref="QueryMtia"/> and <see cref="TemplateMtia"/> objects of the current object respectively.
/// </returns>
public bool Equals(MinutiaPair obj)
{
if (ReferenceEquals(null, obj)) return false;
return obj.QueryMtia.Equals(QueryMtia) && obj.TemplateMtia.Equals(TemplateMtia);
}
/// <summary>
/// Determines wheter the specified object and the current <see cref="MinutiaPair"/> have the same minutiae.
/// </summary>
/// <param name="obj">
/// The object to compare with the current <see cref="MinutiaPair"/>.
/// </param>
/// <returns>
/// True if the <see cref="QueryMtia"/> and <see cref="TemplateMtia"/> objects of the specified pair have the same values as the <see cref="QueryMtia"/> and <see cref="TemplateMtia"/> objects of the current object respectively.
/// </returns>
public override bool Equals(object obj)
{
MinutiaPair mp = obj as MinutiaPair;
return Equals(mp);
}
}
public class MtiaMapper
{
public MtiaMapper(Minutia query, Minutia template)
{
dAngle = template.Angle - query.Angle;
this.template = template;
this.query = query;
}
public Minutia Map(Minutia m)
{
double newAngle = m.Angle + dAngle;
double sin = Math.Sin(dAngle);
double cos = Math.Cos(dAngle);
return new Minutia
{
Angle = (newAngle > 2 * Math.PI) ? newAngle - 2 * Math.PI : (newAngle < 0) ? newAngle + 2 * Math.PI : newAngle,
X = Convert.ToInt16(Math.Round((m.X - query.X) * cos - (m.Y - query.Y) * sin + template.X)),
Y = Convert.ToInt16(Math.Round((m.X - query.X) * sin + (m.Y - query.Y) * cos + template.Y))
};
}
private double dAngle;
private Minutia template;
private Minutia query;
}
}
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