3D-3D facial superimposition between monozygotic twins: A novel morphological approach to the assessment of differences due to environmental factors (original) (raw)
Related papers
Proceedings of 3DBODY.TECH 2017 - 8th International Conference and Exhibition on 3D Body Scanning and Processing Technologies, Montreal QC, Canada, 11-12 Oct. 2017, 2017
The genetic background of the craniofacial development is a sensitive topic: in this context twin studies have had a relevant role as they allow to understand the effect of genes on the anatomical variability observed in the population. In particular, monozygotic twins (MZT) share the same DNA and allow to evaluate the genetic component of a specific morphology. In order to understand the similarities and differences on the facial morphology of MZT in different portions of the face, a thirdbased, superimposition approach was applied to the 3D facial scans of 10 couples of MZT. The experimental subjects were acquired through a stereophotogrammetric system, after the identification of a set of reference landmarks on their facial surfaces. The landmarks were used to segment facial areas of interest from the 3D reconstructions and to subdivide them into thirds, according to the territories of distribution of trigeminal branches for somatic sensitivity. The left and right upper, middle and lower facial thirds of each MZT couple were pairwise superimposed and the root mean square (RMS) point-to-point distances were automatically calculated. Data were statistically analysed through a two-way ANOVA, setting the level of significance at 5%. Post-hoc tests were performed with the necessary reductions in the degrees of freedom. Results revealed statistically significant differences among thirds (p < 0.05), while no differences were found for facial sides (p > 0.05) or for the third x side interaction (p > 0.05). Post hoc tests showed statistically significant differences between the upper and the lower facial thirds, and the middle and lower facial thirds (p < 0.05), with the middle and lower thirds being the more different between the couples. In conclusion, stereophotogrammetric techniques can be valid instruments to analyse the facial morphology of MZT. The acquisition procedure is easy to perform, fast and free from risk, being suitable to obtain multiple subsequent 3D reconstructions. These reconstructions can be superimposed and locally analysed in order to provide an anatomically-based, detailed description of the most similar and different facial areas, useful for the evaluation of the genetic components of a specific morphology.
Comparing Facial 3D Analysis With DNA Testing to Determine Zygosities of Twins
Twin research and human genetics : the official journal of the International Society for Twin Studies, 2015
The aim of this study was to compare facial 3D analysis to DNA testing in twin zygosity determinations. Facial 3D images of 106 pairs of young adult Lithuanian twins were taken with a stereophotogrammetric device (3dMD, Atlanta, Georgia) and zygosity was determined according to similarity of facial form. Statistical pattern recognition methodology was used for classification. The results showed that in 75% to 90% of the cases, zygosity determinations were similar to DNA-based results. There were 81 different classification scenarios, including 3 groups, 3 features, 3 different scaling methods, and 3 threshold levels. It appeared that coincidence with 0.5 mm tolerance is the most suitable feature for classification. Also, leaving out scaling improves results in most cases. Scaling was expected to equalize the magnitude of differences and therefore lead to better recognition performance. Still, better classification features and a more effective scaling method or classification in dif...
Three‐dimensional analysis of facial shape and symmetry in twins using laser surface scanning
Orthodontics & Craniofacial Research, 2012
Structured ObjectivesThree‐dimensional analysis of facial shape and symmetry in twins.Setting and Sample PopulationFaces of 37 twin pairs [19 monozygotic (MZ) and 18 dizygotic (DZ)] were laser scanned at the age of 15 during a follow‐up of the Avon Longitudinal Study of Parents and Children (ALSPAC), South West of England.Material and MethodsFacial shape was analysed using two methods: 1) Procrustes analysis of landmark configurations (63 x, y and z coordinates of 21 facial landmarks) and 2) three‐dimensional comparisons of facial surfaces within each twin pair. Monozygotic and DZ twins were compared using ellipsoids representing 95% of the variation in landmark configurations and surface‐based average faces. Facial symmetry was analysed by superimposing the original and mirror facial images.ResultsBoth analyses showed greater similarity of facial shape in MZ twins, with lower third being the least similar. Procrustes analysis did not reveal any significant difference in facial land...
Facial recognition of identical twins
2011 International Joint Conference on Biometrics (IJCB), 2011
Biometric identification systems must be able to distinguish between individuals even in situations where the biometric signature may be similar, such as in the case of identical twins. This paper presents experiments done in facial recognition using data from a set of images of twins. This work establishes the current state of facial recognition in regards to twins and the accuracy of current state-of-theart programs in distinguishing between identical twins using three commercial face matchers, Cognitec 8.3.2.0, Ver-iLook 4.0, and PittPatt 4.2.1 and a baseline matcher employing Local Region PCA. Overall, it was observed that Cognitec had the best performance. All matchers, however, saw degradation in performance compared to an experiment where the ability to distinguish unrelated persons was assessed. In particular, lighting and expression seemed to have affected performance the most.
Facial marks as biometric signatures to distinguish between identical twins
CVPR 2011 WORKSHOPS, 2011
There exists a high degree of similarity in facial appearance between identical twins that makes it difficult for even the state of the art face matching systems to distinguish between them. Given the consistent increase in the number of twin births in recent decades, there is a need to develop alternate approaches to characterize facial appearance that can address this challenging task that has eluded even humans. In this paper, we investigate the usefulness of facial marks as biometric signatures with focus on the task of distinguishing between identical twins. We define and characterize a set of facial marks that are manually annotated by multiple observers. The geometric distribution of annotated facial marks along with their respective categories is used to characterize twin face images. The analysis is conducted on 295 twin face images acquired at the Twins Days Festival at Twinsburg, Ohio, in 2009. The results of our analysis signify the usefulness of distribution of facial marks as a biometric signature. In addition, contrary to prior research, our results indicate the existence of some degree of correlation between positions of facial marks belonging to identical twins.
Texture Analysis has been an active area of research over the past twenty five years. Today, texture analysis plays an important role in many tasks ranging from remote sensing to bio-medical image analysis. Textures, the repeated patterns, have different frequency components along different orientations. Texture analysis is important in many applications like image database retrieval, industrial, agricultural and bio-medical applications. Texture analysis and classification are based on three different approaches; statistical, spectral and structural. We have proposed statistical approaches for analyzing the faces of twins and the components on the faces. Keywords: texture, remote sensing, orientations, retrieval bio-medical , faces of the twins etc. I. INTRODUCTION Identical twins are also known as monozygotic twins. They result from the fertilization of a single egg that splits into two. Identical twins share all of their genes and are always of the same sex. In contrast, fraternal or dizygotic twins result from the fertilization of two separate eggs during the same pregnancy. They share half of their genes, just like any other siblings. Fraternal twins can be of the same or different sexes. Identical twins are natural clones. Because they start out with the same genes, they can be used to investigate how much heredity contributes to individual people. This is the Nature vs. nurture question. Studies with twins have been quite interesting. If we make a list of characteristic traits, we find that they vary in how much they owe to heredity. For example: Eye colour: entirely inherited. Weight, height: partly inherited, partly environmental. Which language do they speak: entirely environmental. The insight we gain from studying the twins helps us to better understand how nature and nurture works together. Today technologies are well-studied, but research shows they have many drawbacks which decrease the success of the methods applied. The frequently used and most common biological traits in the field of biometrics are face, finger, and iris. Identifying identical twins is crucial for all biometric systems. The systems that cannot handle identical twins have a serious security hole. The present work is first of its kind in the literature and the result is found to be very fruitful. II. TEXTURE ANALYSIS Texture analysis refers to a class of mathematical procedures and models that characterize the spatial variations within imagery as a means of extracting information. Texture is an aerial construct that defines local spatial organization of spatially varying spectral values that is repeated in a region of larger spatial scale. Thus, the perception of texture is a function of spatial and radiometric scales. Descriptors providing measures of properties such as smoothness, coarseness and regularity are used to quantify the texture content of an object. Since an image is made up of pixels, texture can be defined as an entity consisting of mutually related pixels and group of pixels. This group of pixels is called as texture primitives or texture elements (texels). Here, we provide a brief description of a number of texture analysis techniques and some examples.
A group of facial normal descriptors for recognizing 3D identical twins
2012 IEEE Fifth International Conference on Biometrics: Theory, Applications and Systems (BTAS), 2012
In this paper, to characterize and distinguish identical twins, three popular texture descriptors: i.e. local binary patterns (LBPs), gabor filters (GFs) and local gabor binary patterns (LGBPs) are employed to encode the normal components (x, y and z) of the 3D facial surfaces of identical twins respectively. A group of facial normal descriptors are thus achieved, including Normal Local Binary Patterns descriptor (N-LBPs), Normal Gabor Filters descriptor (N-GFs) and Normal Local Gabor Binary Patterns descriptor (N-LGBPs). All these normal encoding based descriptors are further fed into sparse representation classifier (SR-C) for identification. Experimental results on the 3D TEC database demonstrate that these proposed normal encoding based descriptors are very discriminative and efficient, achieving comparable performance to the best of state-ofthe-art algorithms.
Twins 3D face recognition challenge
2011 International Joint Conference on Biometrics (IJCB), 2011
Existing 3D face recognition algorithms have achieved high enough performances against public datasets like FRGC v2, that it is difficult to achieve further significant increases in recognition performance. However, the 3D TEC dataset is a more challenging dataset which consists of 3D scans of 107 pairs of twins that were acquired in a single session, with each subject having a scan of a neutral expression and a smiling expression. The combination of factors related to the facial similarity of identical twins and the variation in facial expression makes this a challenging dataset. We conduct experiments using state of the art face recognition algorithms and present the results. Our results indicate that 3D face recognition of identical twins in the presence of varying facial expressions is far from a solved problem, but that good performance is possible.