Forensic evidence is the evidence obtained by scientific methods such as ballistics, blood test, and DNA test and used in court. Forensic evidence often helps to establish the guilt or innocence of possible suspects. What are the steps required to seize forensic evidence? First, obtain authorization to search and seize; secure the area, which may be a crime scene; document the chain of custody of every item that was seized; bag, tag, and safely transport the equipment and e-evidence. Hearsay is an out-of-court statement offered to prove the truth of whatever it asserts. Hearsay evidence is often inadmissible at trial. This is because one cannot cross examine the person who is making the statement since that person is not in court. At its core, the rule against using hearsay evidence is to prevent out-of-court, second hand statements from being used as evidence at trial given their potential unreliability.
Geometric Feature Based Methods, Template Based Methods, Correlation Based Methods, Matching, Pursuit Based Methods, Singular Value Decomposition Based Methods, The Dynamic Link, Matching Methods, Illumination Invariant Processing Methods, Support Vector Machine Approach, Karhunen- Loeve Expansion Based Methods, Feature Based Methods, Neural Network Based Algorithms and Model Based Methods [25].
Later on, one of the most known methods will be discussed in a detailed way. The facial recognition methods that can be used, all have a different approach. Some are more frequently used for facial recognition algorithms than others. The use of a method also depends on the needed applications. For instance, surveillance applications may best be served by capturing face images by means of a video camera while image database investigations may require static intensity images taken by a standard camera. Some other applications, such as access to top security domains, may even necessitate the forgoing of the nonintrusive quality of face recognition by requiring the user to stand in front of a 3D scanner or an infrared sensor[15]. Consequently, there can be concluded that there can be made a division of three groups of face recognition techniques, depending on the wanted type of data results, i.e. methods that compare images, methods that look at data from video cameras and methods that deal with other sensory data, like 3D pictures or infrared imagery. All of them can be used in different ways, to prevent crime from happening or recurring.
ii. How do these technologies work?
As listed above, there exists a long list of methods and algorithms that can be used for facial recognition. Four of them are used frequently and are most known in the literature, i.e. Eigenface Method, Correlation Method, Fisherface Method and the Linear Subspaces Method. But how do these facial recognition work? Because of word limitations, only one of those four facial recognition techniques, i.e The Eigenface Method, will be discussed. Hopefully this will give an general idea of how facial recog
