The Changes Of Portrait Features

In 1826,the French scientist Joseph Nicephorus Nieces took the first photo in the word.It opened a new chapter in the portrait fixed.With the gradually continuous development of science and technology,mobile phones,video,photography,and with the widely covered of surveillance cameras,the number of portraits which are recorded by photos or video become larger and larger.So,the cases involved image identification increase quickly,and,portraits identification have become most universal in them.In practice,the suspects often do not recognize their crimes,and the clients often require to identify whether the person recorded in the portrait and the sample portrait are the same person.Portraits identification is a scientific judgment telling about the identification of the portrait which is recorded in the audiovisual data and identified through the comparison,analysis.The first step of portrait identification is to analysis the features of portrait,and then comprehensive comparison.It includes not only the static features of the characters,the separate verification of the dynamic features,but also the comprehensive analysis of the static and dynamic features.Analysis the features ’characteristics,and build the basis of analysis and comparison.In this process,it includes not only similarity features,but also difference features.How to select features,and assess features,has always been the core of the portraits identification.The changes of portrait features play a vital role in portrait identification.Study the changes of portrait features,can fully understand and apply the value of portrait features.In practice,the features of video portraits are often more complex,and the change probability of some portrait features are higher,then the feature reference value for identification is low.On the contrary,if the stability of portrait features is strong,and difficult to change,the feature reference value for identification is relatively strong.Moreover,when portrait features is unclear,or the case is difficult to distinguish,the study of changes in the portrait features can make it easier to decide whether the features can be used as a consistent basis for the portrait,or as a basis for the inconsistency of the portrait.At the same time,the study of changes in the portrait features help us to carry out a reasonable scientific explanation of the differences in the process of identification,also help us to recognize the portrait features changes whether are part of the people essential differences,or just thanks to shooting conditions,or belong to their own physiological changes.And it can more fully demonstrate the identification of opinions,ensure opinions’ correctness.In general,the study of the changes in the portrait features is conducive to our effective,reasonable and fast analysis of portrait features,and then to obtain the correct conclusions.Therefore,it is necessary for us to study the changes of the portrait features.Based on the detailed analysis of the portrait features involved in the portrait identification,this paper analyzes the changes of the portrait features from the aspects of age,shooting distance,shooting angle,accessories,facial expression,makeup and surgical shaping.Through the way of experimental design,collecting portraits,data statistics and some other ways,we can conduct a detailed discussion and analysis the regular facial features changes in these cases.Clear the possible changes in portrait features,established the knowledge system of changes in portrait features.In response to the changes in portrait features,put forward the strategy in practice.At last,there is a case analysis in the paper.And the case analysis is according to the above methods.This paper not only enriches and consummates the knowledge system and context of the portrait features,but also lay a solid theoretical foundation for practical portrait identification,and promote the systematic and setandardization of the process of the portrait identification.