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Simetria e atratividade facial / Symmetry and facial attractivenessSilva, Luciana Maria da 18 March 2005 (has links)
A simetria facial foi investigada como fator de atratividade em quatro experimentos. Fotos frontais em preto e branco de faces de homens e mulheres foram manipuladas por computação gráfica para gerar faces simétricas. No Exp. I as faces simétricas foram geradas a partir da reflexão das metades laterais, direita e esquerda, de cada face. Essas faces simétricas e suas respectivas faces naturais foram apresentadas a sujeitos para julgar o quão atrativa elas eram. Os resultados mostraram que faces assimétricas (naturais) foram julgadas como mais atrativas que as simétricas. No Exp. II utilizaram-se as mesmas faces simétricas e naturais do Exp. I, porém, excluindo-se os elementos externos da face por meio de uma moldura elíptica. Essas faces foram apresentadas aos pares e pediu-se para os participantes escolher a mais atrativa, além de julgar seu grau de atratividade. Os resultados mostraram que nenhuma foto simétrica foi julgada como mais atrativa que sua respectiva face natural, bem como as faces naturais foram mais escolhidas que as simétricas. A exclusão dos elementos externos das faces não contribuiu para aumentar o grau de atratividade das mesmas. No Exp. III as faces simétricas foram geradas por técnica de morphing a partir da imagem da face original e a sua respectiva imagem refletida. A apresentação e julgamentos das faces seguiram o modelo do Exp. II. Os resultados mostraram que nenhuma face simétrica obteve escore de atratividade maior que as naturais, mas com relação às escolhas, para faces masculinas houve maior número de escolhas para as faces simétricas. No Exp. IV foram utilizadas as mesmas faces simétricas e naturais do Exp. III, excluindo-se os elementos faciais externos. Os resultados indicaram maior escores de atratividade, bem como um maior número de escolhas das faces simétricas. Comparadas ao Exp. III houve um aumento nos escores de atratividade para as faces simétricas e uma diminuição dos escores para as faces naturais. Conclui-se que a simetria não deve ser considerada como um fator isolado na análise da atratividade facial; relações entre outros elementos podem contribuir para tornar uma face mais atrativa. / The facial symmetry was investigated as attractiveness factor in four experiments. Front pictures in black and white of men\'s and women?s faces were manipulated by graphic computation to create symmetrical faces. In Exp. I, the symmetrical faces were created starting from the lateral half right and left reflection, of each face. Those symmetrical faces and their respective natural faces were presented to people that had to judge how attractive they were. The results showed that asymmetrical faces (natural) were judged as more attractive than the symmetrical ones. In Exp. II, we used the same symmetrical and natural faces of Exp. I, however, being excluded face?s external elements through an elliptic frame. These faces were presented in pairs and we asked for the participants to choose the most attractive, besides judging the attractiveness degree. The results showed that no symmetrical picture was judged as more attractive than its respective natural face, as well as the natural faces were more chosen than the symmetrical ones. The exclusion of the external elements of the faces didn\'t contribute to increase the attractiveness degree of themselves. In Exp. III, the symmetrical faces were created by morphing technique starting from the original face image and its respective reflected image. The presentation and judgments of the faces followed the model of Exp. II. The results showed that no symmetrical face obtained score of larger attractiveness than the natural ones, but regarding the choices, for masculine faces there was larger number of choices for the symmetrical faces. In Exp. IV we used the same symmetrical and natural faces of Exp. III, being excluded the external facial elements. The results indicated larger attractiveness scores, as well as a larger number of choices fore the symmetrical faces. Comparing Exp. IV with Exp. III, we had an increase in the attractiveness scores for the symmetrical faces and a decrease of the scores for the natural faces. We concluded that the symmetry should not be considered as an isolated factor in the facial attractiveness analysis; the relationships among other elements can contribute to turn a more attractive face.
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Atratividade facial e cirurgia ortognática: aspectos físicos e emocionais / Facial Attractiveness and Orthognatic Surgery: Emotional and Physical AspectsSilva, Luciana Maria da 22 April 2009 (has links)
Pessoas que apresentam grandes deformidades dentofaciais podem ter prejuízos sociais, pessoais e emocionais. A cirurgia ortognática é utilizada para correções dessas deformidades, que consequentemente afeta as aparências das faces dos pacientes. Este estudo teve como objetivos: 1) Avaliar amostras de faces da população de Ribeirão Preto, SP e as faces prototípicas provenientes delas, consideradas sem deformidades; 2) Analisar atratividade facial de dez pacientes submetidos a cirurgias ortognáticas nas fases pré e pós-cirúrgicas; ao relacionar suas atratividades aos parâmetros físicos alterados pela cirurgia; e também avaliar as consequências na qualidade de vida, ansiedade e auto-estima destes pacientes. As análises faciais foram frontais e obedeceram aos critérios preconizados na literatura de meios, terços e quintos faciais. A coleta de dados com os pacientes foi feita no CEDEFACE (Centro de Pesquisa e Tratamento das Deformidades Buco-Faciais). Foram obtidas fotografias nas fases pré e pós-cirúrgicas; momentos em que também foram aplicadas escalas de qualidade de vida (WHOQOL bref), de ansiedade (IDATE e Escala Analógica de Humor) e autoestima (Escala de Autoestima de Rosenberg). Dois experimentos foram realizados. Um com as fotos das faces pré e pós-cirúrgicas a fim de avaliar a atratividade facial dos pacientes antes e depois das cirurgias e outro para comparar a atratividade facial dos pacientes com a atratividade de faces prototípicas relativas ao sexo e etnia correspondentes. Nesses experimentos os julgamentos de atratividade foram provenientes de uma amostra de 40 participantes leigos. Os resultados apontaram que: 1) As análises do banco de faces e protótipos apresentaram parâmetros físicos faciais diferentes daqueles apontados na literatura, principalmente na análise dos terços e quintos; 2) A cirurgia ortognática contribuiu para o aumento da atratividade dos pacientes, embora estes ainda considerados menos atrativos que as faces prototípicas. Também foram notadas melhoria na condição psicológica por meio do Whoqol bref e diminuição da ansiedade por meio da Escala Analógica de Humor. Tais resultados apontam para a importância de estudos sobre parâmetros físicos faciais relacionados à melhoria de sua estética e que a cirurgia ortognática para o tratamento de deformidades dentofaciais pode trazer benefícios estéticos e emocionais àqueles que a procuram. / People with salient dentofacial deformities can have social, personal and emotional injury. The orthognathic surgery is used to correct these deformities, and consequently, it affects the facial appearances of the patients. The general aims of this study were: 1) Evaluate samples of faces from a population of Ribeirão Preto, SP and their prototypical faces considered as without deformities; 2) Analyze the facial attractiveness of ten patients before and after being submitted to orthognathic surgery; searching the relationship between the attractiveness and physical parameters modified on the faces by the surgery; and also assessing the effects of this surgery on the quality of life, the anxiety and the self-esteem of these patients. The facial analyses were frontal and from the halves, the thirds and the fifths of the faces. The pictures of faces before and after the orthognathic surgery were from voluntary patients from CEDEFACE (Centro de Pesquisa e Tratamento das Deformidades Buco-Faciais) at Araraquara, SP. Before and after the surgery, these patients also had their quality of life (by WHOQOL bref scale), the anxiety (by IDATE and Escala Analógica de Humor) and the selfesteem (by Escala de Auto-Estima de Rosenberg) evaluated. There were two experiments. From an experiment, forty volunteers judged the attractiveness of the faces pictured before and after the surgery. From the other experiment, the volunteers compared the attractiveness of the patient faces with the attractiveness of the prototypical faces, respectively to their sex and race. The results showed that: 1) The facial analyses of the faces from population sample of Ribeirão Preto, SP, and their prototypical faces indicated physical parameters that differ from the literature, mainly for the facial analyses of the thirds and the fifths 2) The orthognathic surgery contributed to increase the facial attractiveness of the patients, although they were still considered less attractive than the prototypical faces. Improvement in psychological condition, assessed by the Whoqol bref, and anxiety decrement, assessed by the Escala Analógica de Humor, were noticed. These results pointed out the importance to study facial analyses related to the aesthetic improvement, and that the orthognathic surgery to treat dentofacial deformities can bring aesthetic and emotional benefits to the patients.
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Julgamento de atratividade facial por mulheres durante o ciclo menstrual / Judgment of facial attractiveness by women during the menstrual cyclePerin, Cristina 11 August 2014 (has links)
Este projeto teve por objetivo investigar se existem diferenças nos julgamentos de atratividade de faces masculinizadas e feminilizadas entre mulheres durante a etapa folicular tardia e na etapa luteal (fases do ciclo menstrual) e se estas se correlacionam às alterações dos níveis hormonais. Foram incluídas 30 mulheres voluntárias, na faixa etária de 18 a 42 anos com ciclos menstruais regulares, com duração entre 24 e 33 dias, sem uso de anticoncepcional hormonal (AH). Foram utilizados para a avaliação da atratividade facial dois protótipos faciais: um de uma face feminina e outro de face masculina. De cada um desses protótipos foram confeccionadas mais quatro faces, cujos traços de duas foram masculinizados e das outras duas foram feminilizados em diferentes graus. Foram realizadas duas sessões experimentais para cada participante. A primeira sessão foi na etapa folicular tardia do ciclo menstrual e a segunda na etapa luteal do ciclo. Em cada sessão, a participante era instruída a ordenar decrescentemente as faces conforme o quão atraente cada uma lhe parecerá. Em seguida a participante classificava as faces em três grupos: Amigo, Inimigo e Amante. Posteriormente foi colhida a amostra de sangue para posteriores análises dos níveis hormonais. Ou seja, tanto na etapa folicular tardia quanto na luteal, as participantes avaliaram as imagens das faces e doaram uma amostra de sangue. As frequências foram comparadas e verificou-se que para as faces masculinas masculinizadas e a face neutra foram consideradas as mais atraentes na fase folicular tardia e na fase lútea. Na fase folicular tardia, para as faces masculinas, quanto mais masculinizadas elas forem, maior sua pontuação no grupo Amante. Na fase lútea, a face original masculina e todas as faces masculinas masculinizadas foram mais frequentemente classificadas ao grupo Amante, mas a face 50% masculinizada teve um aumento na qualificação de Inimigo. E finalmente, não foi verificada uma correlação entre os níveis hormonais e a preferência por faces mais masculinizadas ou feminilizada. Não foi evidenciada uma mudança significativa na preferência do julgamento das faces; observando-se que existe sempre uma preferência por faces mais masculinizadas para faces masculinas, e preferência por faces mais feminilizadas para faces femininas, independente das fases do ciclo menstrual. / This project aimed to investigate whether there are differences in attractiveness judgments of masculinized and feminized faces by women during the late follicular and the luteal phases (phases of the menstrual cycle) and whether these judgments correlate with hormonal level changes. Thirty women with age between 18 and 42 years old, with regular menstrual cycles lasting between 24 and 33 days, and without use of hormonal contraceptive (AH) were volunteers in this study. Stimuli were images of a female and a male prototypical faces that by computer morphing technique generated other faces with exaggeration of the gender traits by 25% and 50%. Two experimental sessions, the first in the late follicular phase and the second in the luteal phase, were conducted for each participant to judge the attractiveness of the faces, sorting them from the highest to lowest attractive. Finishing this task, the participant classified the faces into three groups: \"Friend\", \"Enemy\" or \"Lover.\" After each session in both menstrual phases blood sample of the participant was collected for further hormone level analysis. The masculinized male face and the original male face were chosen as more attractive in the follicular phase and the late luteal phase. Besides, in the late follicular phase, the more masculinized are the male faces, the higher is their score into the \"Lover\" group. In the luteal phase, also all masculinized and the original male faces were classified more frequently into the Lover group, but also the 50% masculinized male face was more frequently classified into the Enemy group. And finally, there was no correlation between hormone levels and preference for more masculinized or more feminized faces. Then, there is no evidence that hormonal levels change the face preferences. There was always a preference for masculinized faces to male faces, and preference for feminized faces for female faces, regardless of the menstrual cycle phases.
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A matching algorithm for facial memory recall in forensic applications.January 2000 (has links)
by Lau Kwok Kin. / Thesis (M.Phil.)--Chinese University of Hong Kong, 2000. / Includes bibliographical references (leaves 82-87). / Abstracts in English and Chinese. / List of Figures --- p.vi / List of Tables --- p.vii / Chapter 1 --- Introduction --- p.1 / Chapter 1.1 --- Objective of This Thesis --- p.3 / Chapter 1.2 --- Organization of This Thesis --- p.3 / Chapter 2 --- Literature Review --- p.4 / Chapter 2.1 --- Facial Memory Recall --- p.4 / Chapter 2.2 --- Facial Recognition --- p.6 / Chapter 2.2.1 --- Earlier Approaches --- p.7 / Chapter 2.2.2 --- Feature and Template Matching --- p.8 / Chapter 2.2.3 --- Neural Network --- p.10 / Chapter 2.2.4 --- Statistical Approach --- p.14 / Chapter 3 --- A Forensic Application of Facial Recall --- p.19 / Chapter 3.1 --- Motivation --- p.20 / Chapter 3.2 --- AICAMS-FIT --- p.20 / Chapter 3.2.1 --- The Facial Component Library --- p.21 / Chapter 3.2.2 --- The Feature Selection Module --- p.24 / Chapter 3.2.3 --- The Facial Construction Module --- p.24 / Chapter 3.3 --- The Interaction Between The Three Main Components --- p.29 / Chapter 3.4 --- Summary --- p.30 / Chapter 4 --- Sketch-to-Sketch Matching --- p.31 / Chapter 4.1 --- The Representation of A Composite Face --- p.31 / Chapter 4.2 --- The Component-based Encoding Scheme --- p.32 / Chapter 4.2.1 --- Local Feature Analysis --- p.34 / Chapter 4.2.2 --- Similarity Matrix --- p.36 / Chapter 4.3 --- Experimental Results and Evaluation --- p.41 / Chapter 4.4 --- Shortcomings of the encoding scheme --- p.44 / Chapter 4.4.1 --- Size Variation --- p.45 / Chapter 4.5 --- Summary --- p.51 / Chapter 5 --- Sketch-to-Photo/Photo-to-Sketch Matching --- p.52 / Chapter 5.1 --- Principal Component Analysis --- p.53 / Chapter 5.2 --- Experimental Setup --- p.56 / Chapter 5.3 --- Experimental Results --- p.59 / Chapter 5.3.1 --- Sketch-to-Photo Matching --- p.59 / Chapter 5.3.2 --- Photo-to-Sketch Matching --- p.62 / Chapter 5.4 --- Summary --- p.66 / Chapter 6 --- Future Work --- p.67 / Chapter 7 --- Conclusions --- p.70 / Chapter A --- Image Library I --- p.72 / Chapter A.1 --- The Database for Searching --- p.72 / Chapter A.2 --- The Database for Testing --- p.74 / Chapter B --- Image Library II --- p.75 / Chapter B.1 --- The Photographic Database --- p.75 / Chapter B.2 --- The Sketch Database --- p.77 / Chapter C --- The Eigenfaces --- p.78 / Chapter C.1 --- Eigenfaces of Photographic Database (N = 20) --- p.78 / Chapter C.2 --- Eigenfaces of Photographic Database (N = 100) --- p.79 / Chapter C.3 --- The Eigenfaces of Sketch Database --- p.81 / Bibliography --- p.82
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Rotation-invariant face detection in grayscale images.January 2005 (has links)
Zhang Wei. / Thesis (M.Phil.)--Chinese University of Hong Kong, 2005. / Includes bibliographical references (leaves 73-78). / Abstracts in English and Chinese. / Abstract --- p.i / Acknowledgement --- p.ii / List of Figures --- p.viii / List of Tables --- p.ix / Chapter 1 --- Introduction --- p.1 / Chapter 1.1 --- Previous work --- p.2 / Chapter 1.1.1 --- Learning-based approaches --- p.3 / Chapter 1.1.2 --- Feature-based approaches --- p.7 / Chapter 1.2 --- Thesis objective --- p.12 / Chapter 1.3 --- The proposed detector --- p.13 / Chapter 1.4 --- Thesis outline --- p.14 / Chapter 2 --- The Edge Merging Algorithm --- p.16 / Chapter 2.1 --- Edge detection --- p.16 / Chapter 2.2 --- Edge breaking --- p.18 / Chapter 2.2.1 --- Cross detection --- p.20 / Chapter 2.2.2 --- Corner detection --- p.20 / Chapter 2.3 --- Curve merging --- p.23 / Chapter 2.3.1 --- The search region --- p.25 / Chapter 2.3.2 --- The merging cost function --- p.27 / Chapter 2.4 --- Ellipse fitting --- p.30 / Chapter 2.5 --- Discussion --- p.33 / Chapter 3 --- The Face Verifier --- p.35 / Chapter 3.1 --- The face box --- p.35 / Chapter 3.1.1 --- Face box localization --- p.36 / Chapter 3.1.2 --- Conditioning the face box --- p.42 / Chapter 3.2 --- Eye-mouth triangle search --- p.45 / Chapter 3.3 --- Face model matching --- p.48 / Chapter 3.3.1 --- Face model construction --- p.48 / Chapter 3.3.2 --- Confidence of detection --- p.51 / Chapter 3.4 --- Dealing with overlapped detections --- p.51 / Chapter 3.5 --- Discussion --- p.53 / Chapter 4 --- Experiments --- p.55 / Chapter 4.1 --- The test sets --- p.55 / Chapter 4.2 --- Experimental results --- p.56 / Chapter 4.2.1 --- The ROC curves --- p.56 / Chapter 4.3 --- Discussions --- p.61 / Chapter 5 --- Conclusions --- p.69 / Chapter 5.1 --- Conclusions --- p.69 / Chapter 5.2 --- Suggestions for future work --- p.70 / List of Original Contributions --- p.72 / Bibliography --- p.73
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Symmetry for face analysis.January 2005 (has links)
Yuan Tianqiang. / Thesis (M.Phil.)--Chinese University of Hong Kong, 2005. / Includes bibliographical references (leaves 51-55). / Abstracts in English and Chinese. / abstract --- p.i / acknowledgments --- p.iv / table of contents --- p.v / list of figures --- p.vii / list of tables --- p.ix / Chapter Chapter 1 --- Introduction --- p.1 / Chapter 1.1 --- Reflectional Symmetry Detection --- p.1 / Chapter 1.2 --- Research Progress on Face Analysis --- p.2 / Chapter 1.2.1 --- Face Detection --- p.3 / Chapter 1.2.2 --- Face Alignment --- p.4 / Chapter 1.2.3 --- Face Recognition --- p.6 / Chapter 1.3 --- Organization of this thesis --- p.8 / Chapter Chapter 2 --- Local reflectional symmetry detection --- p.9 / Chapter 2.1 --- Proposed Method --- p.9 / Chapter 2.1.1 --- Symmetry measurement operator --- p.9 / Chapter 2.1.2 --- Potential regions selection --- p.10 / Chapter 2.1.3 --- Detection of symmetry axes --- p.11 / Chapter 2.2 --- Experiments --- p.13 / Chapter 2.2.1 --- Parameter setting and analysis --- p.13 / Chapter 2.2.2 --- Experimental Results --- p.14 / Chapter Chapter 3 --- Global perspective reflectional symmetry detection --- p.16 / Chapter 3.1 --- Introduction of camera models --- p.16 / Chapter 3.2 --- Property of Symmetric Point-Pair --- p.18 / Chapter 3.3 --- analysis and Experiment --- p.20 / Chapter 3.3.1 --- Confirmative Experiments --- p.20 / Chapter 3.3.2 --- Face shape generation with PSI --- p.22 / Chapter 3.3.3 --- Error Analysis --- p.24 / Chapter 3.3.4 --- Experiments of Pose Estimation --- p.25 / Chapter 3.4 --- Summary --- p.28 / Chapter Chapter 4 --- Pre-processing of face analysis --- p.30 / Chapter 4.1 --- Introduction of Hough Transform --- p.30 / Chapter 4.2 --- Eye Detection --- p.31 / Chapter 4.2.1 --- Coarse Detection --- p.32 / Chapter 4.2.2 --- Refine the eyes positions --- p.34 / Chapter 4.2.3 --- Experiments and Analysis --- p.35 / Chapter 4.3 --- Face Components Detection with GHT --- p.37 / Chapter 4.3.1 --- Parameter Analyses --- p.38 / Chapter 4 3.2 --- R-table Construction --- p.38 / Chapter 4.3.3 --- Detection Procedure and Voting Strategy --- p.39 / Chapter 4.3.4 --- Experiments and Analysis --- p.41 / Chapter Chapter 5 --- Pose estimation with face symmetry --- p.45 / Chapter 5.1 --- Key points selection --- p.45 / Chapter 5.2 --- Face Pose Estimation --- p.46 / Chapter 5.2.1 --- Locating eye corners --- p.46 / Chapter 5.2.2 --- Analysis and Summary --- p.47 / Chapter Chapter 6 --- Conclusions and future work --- p.49 / bibliography --- p.51
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Deformable 3D face tracking in real world scenarios. / CUHK electronic theses & dissertations collection / Digital dissertation consortiumJanuary 2010 (has links)
Finally, a performance driven face animation system is introduced. The proposed system consists of two key components: a robust non-rigid 3D tracking module and a MPEG4 compliant facial animation module. Firstly, the facial motion is tracked from source videos which contain both the rigid 3D head motion (6 DOF) and the non-rigid expression variation. Afterward, the tracked facial motion is parameterized via estimating a set of MPEG4 facial animation parameters (FAP) and applied to drive the animation of the target avatar. / In the first part of the thesis, the problem of tracking a non-rigid 3D face is studied. A novel framework for non-rigid 3D face tracking is proposed for applications in live scenarios. In order to extract more information of feature correspondences, the proposed framework integrates three types of features which discriminate face deformation across different views. The integration of these complementary features is important for robust estimation of the 3D parameters. In order to estimate the high dimensional 3D deformation parameters, we develop a hierarchical parameter estimation algorithm to robustly estimate both rigid and non-rigid 3D parameters. We show the importance of both features fusion and hierarchical parameter estimation for reliable tracking 3D face deformation. Experiments demonstrate the robustness and accuracy of the proposed algorithm especially in the cases of agile head motion, drastic illumination change, and large pose change up to profile view. / The video based face recognition is studied in the second part of the thesis. Compared to the still image based recognition methods, the video based methods share the merits of spatial temporal coherence among image sequences and overcomplete training samples. We propose a framework for the task of face recognition in real-world noisy videos based on 3D deformable face tracking, which can directly estimate face pose for a view-based face recognition scheme. Meanwhile, the precise non-rigid tracking provides well-aligned face samples for the subsequent recognizer. At the recognition stage, three types of feature descriptors, including Regularized LDA, LE and sparse representation, are exploited. Extensive experiments conducted on the real world videos demonstrate that the proposed recognition framework can achieve the state-of-the art recognition results, even with the usage of a simple classifier. / Three dimensional face tracking is a crucial task for many applications in computer vision. Problem like face recognition, facial expression analysis and animation, are more likely to be solved by if the geometry and appearance properties are available through a 3D face tracker. / Zhang, Wei. / Adviser: Xiaoon Tang. / Source: Dissertation Abstracts International, Volume: 72-04, Section: B, page: . / Thesis (Ph.D.)--Chinese University of Hong Kong, 2010. / Includes bibliographical references (leaves 102-113). / Electronic reproduction. Hong Kong : Chinese University of Hong Kong, [2012] System requirements: Adobe Acrobat Reader. Available via World Wide Web. / Electronic reproduction. Ann Arbor, MI : ProQuest Information and Learning Company, [200-] System requirements: Adobe Acrobat Reader. Available via World Wide Web. / Electronic reproduction. Ann Arbor, MI : ProQuest Information and Learning Company, [200-] System requirements: Adobe Acrobat Reader. Available via World Wide Web. / Abstract also in Chinese.
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Modeling and rendering from multiple views. / CUHK electronic theses & dissertations collectionJanuary 2006 (has links)
The first approach, described in the first part of this thesis, studies 3D face modeling from multi-views. Today human face modeling and animation techniques are widely used to generate virtual characters and models. Such characters and models are used in movies, computer games, advertising, news broadcasting and other activities. We propose an efficient method to estimate the poses, the global shape and the local structures of a human head recorded in multiple face images or a video sequence by using a generic wireframe face model. Based on this newly proposed method, we have successfully developed a pose invariant face recognition system and a pose invariant face contour extraction method. / The objective of this thesis is to model and render complex scenes or objects from multiple images taken from different viewpoints. Two approaches to achieve this objective were investigated in this thesis. The first one is for known objects with prior geometrical models, which can be deformed to match the objects recorded in multiple input images. The second one is for general scenes or objects without prior geometrical models. / The proposed algorithms in this thesis were tested on many real and synthetic data. The experimental results illustrate their efficiency and limitations. / The second approach, described in the second part of this thesis, investigates 3D modeling and rendering for general complex scenes. The entertainment industry touches hundreds of millions of people every day, and synthetic pictures and 3D reconstruction of real scenes, often mixed with actual film footage, are now common place in computer games, sports broadcasting, TV advertising and feature films. A series of techniques has been developed to complete this task. First, a new view-ordering algorithm was proposed to organize and order an unorganized image database. Second, a novel and efficient multiview feature matching approach was developed to calibrate and track all views. Finally, both match propagation based and Bayesian based methods were developed to produce 3D scene models for rendering. / Yao Jian. / "September 2006." / Adviser: Wai-Kuen Chan. / Source: Dissertation Abstracts International, Volume: 68-03, Section: B, page: 1849. / Thesis (Ph.D.)--Chinese University of Hong Kong, 2006. / Includes bibliographical references (p. 170-181). / Electronic reproduction. Hong Kong : Chinese University of Hong Kong, [2012] System requirements: Adobe Acrobat Reader. Available via World Wide Web. / Electronic reproduction. [Ann Arbor, MI] : ProQuest Information and Learning, [200-] System requirements: Adobe Acrobat Reader. Available via World Wide Web. / Abstracts in English and Chinese. / School code: 1307.
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Mental-state and emotion understanding across childhood : individual differences and relations with social competenceMartin, Natasha, n/a January 2009 (has links)
Mental-state and emotion understanding are important constructs for successful interpretation of behaviour and interaction with others. While false-belief understanding has been the main focus of investigations into children�s mentalising over the past 30 years, we now have tasks available that allow assessment of a broader range and more advanced set of mentalising skills amongst older age groups of typically developing young people (Baron-Cohen, Jolliffe, Mortimore, & Robertson, 1997a; Baron-Cohen, O�Riordan, Stone, Jones, & Plaisted, 1999; Happé, 1994). A recent trend has seen a shift away from investigating when children attain these skills towards examining individual differences in their performance. This has included consideration of both the factors that contribute to (Carlson & Moses, 2001; Hughes & Dunn, 1997; Meins et al., 2002; Milligan, Astington, & Dack, 2007; Ruffman, Slade, & Crowe, 2002), and the factors that are influenced by (Astington & Jenkins, 2000; Cassidy, Werner, Rourke, Zubernis, & Balaraman, 2003; Diesendruck & Ben-Eliyahu, Repacholi, Slaughter, Pritchard, & Gibbs, 2003) individual differences in mental-state understanding. One of the interesting questions in this area is what are the subsequent benefits or harm that individual differences in mentalising and emotion skills hold for children�s social competence?
The current study investigates young people�s growing socioemotional understanding and how it is related to their social abilities, both prosocial and antisocial. The aims were to provide information on the relations amongst advanced mental-state skills, to investigate how these skills were related to emotion understanding, and, further, to investigate how socioemotional skills were related to social competence. The current study also extended the literature by addressing these aims amongst older children. Two studies were conducted, involving children (4- to 7-years) seen on four occasions in a three-year longitudinal study, and adolescents (13- to 17-years) in a cross-sectional study. There were a number of key findings. Individual differences in children�s advanced mental-state understanding are relatively stable across time, and the relations which they show with emotion skills are more consistent when examining tasks that shared skill sets. Language plays an important mediating role in the relation between socioemotional skills, although this influence appears to decrease with age. Mental-state and emotion understanding are both important for children and adolescents� social competence. It seems that greater socioemotional abilities influence prosocial behaviours, and poorer socioemotional abilities influence antisocial behaviours. Overall, the current study provides evidence that socioemotional skills are overlapping but distinct constructs, that they show varied interactions in social settings, and that future investigations of how children come to understand and interact with others will be best served by careful consideration of appropriate measures and by including multiple aspects of children�s social cognition.
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Localization Facial Symmetry Perception Through FmriYildirim, Funda 01 October 2012 (has links) (PDF)
Humans are extremely sensitive and accurate about detecting the amount of symmetry that a face possesses. However perception of facial symmetry has not been investigated in terms of its neural correlates yet. In this thesis, we investigated localization of facial symmetry perception in the brain through the use of the fMR-adaptation method. In this method, marginally active neuronal populations can be detected by presenting faces with varying symmetry. By standardizing all aspects of the faces such as illumination, pose and contrast, we manipulated only the amount of fluctuating asymmetry in the face images. Previous studies have shown that a specific area, lateral occipital complex (LOC) exhibits sensitivity to orientation and position changes to faces and other objects. We observed that facial symmetry activation is specifically localized within the LOC boundaries. Within the LOC, we found that previously defined areas namely LO1 and LO2 are both responsive to manipulations of facial symmetry. We also tested our fMR-adaptation paradigm on non-face images, generated by scrambling the face stimuli used in our experiments. We replicated earlier results which demonstrated that LO1 and LO2 are activated in detecting differences between symmetric versus asymmetric patches. This suggests that although facial symmetry perception is not processed by a function specific area of the LOC, it uses main resources allocated for the object recognition system in an efficient manner. To the best of our knowledge, our study is the first to investigate face symmetry perception through fMR-adaptation.
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