Contextual Face Recognition with a Nested-Hierarchical Nonparametric Identity Model

Current face recognition systems typically operate via classification into known identities obtained from supervised identity annotations. There are two problems with this paradigm: (1) current systems are unable to benefit from often abundant unlabelled data; and (2) they equate successful recognition with labelling a given input image. Humans, on the other hand, regularly perform identification of individuals completely unsupervised, recognising the identity of someone they have seen before even without being able to name that individual. How can we go beyond the current classification paradigm towards a more human understanding of identities? In previous work, we proposed an integrated Bayesian model that coherently reasons about the observed images, identities, partial knowledge about names, and the situational context of each observation. Here, we propose extensions of the contextual component of this model, enabling unsupervised discovery of an unbounded number of contexts for improved face recognition.

[1]  Bernhard Schölkopf,et al.  Introduction to Semi-Supervised Learning , 2006, Semi-Supervised Learning.

[2]  J. Pitman,et al.  The two-parameter Poisson-Dirichlet distribution derived from a stable subordinator , 1997 .

[3]  J. Pitman Combinatorial Stochastic Processes , 2006 .

[4]  A. Gelfand,et al.  The Nested Dirichlet Process , 2008 .

[5]  Mahadev Satyanarayanan,et al.  OpenFace: A general-purpose face recognition library with mobile applications , 2016 .

[6]  Thomas L. Griffiths,et al.  The nested chinese restaurant process and bayesian nonparametric inference of topic hierarchies , 2007, JACM.

[7]  T. Ferguson A Bayesian Analysis of Some Nonparametric Problems , 1973 .

[8]  D. Cox Some Statistical Methods Connected with Series of Events , 1955 .

[9]  W. Eric L. Grimson,et al.  Unsupervised Activity Perception in Crowded and Complicated Scenes Using Hierarchical Bayesian Models , 2008, IEEE Transactions on Pattern Analysis and Machine Intelligence.

[10]  Indrajit Bhattacharya,et al.  Nested Hierarchical Dirichlet Process for Nonparametric Entity-Topic Analysis , 2013, ECML/PKDD.

[11]  Yee Whye Teh,et al.  Dirichlet Process , 2017, Encyclopedia of Machine Learning and Data Mining.

[12]  C. Antoniak Mixtures of Dirichlet Processes with Applications to Bayesian Nonparametric Problems , 1974 .

[13]  J. Sethuraman A CONSTRUCTIVE DEFINITION OF DIRICHLET PRIORS , 1991 .

[14]  John W. Fisher,et al.  A Dirichlet Process Mixture Model for Spherical Data , 2015, AISTATS.

[15]  M. Escobar,et al.  Markov Chain Sampling Methods for Dirichlet Process Mixture Models , 2000 .

[16]  Sebastian Nowozin,et al.  From Face Recognition to Models of Identity: A Bayesian Approach to Learning about Unknown Identities from Unsupervised Data , 2018, ECCV.

[17]  Michael I. Jordan,et al.  Hierarchical Dirichlet Processes , 2006 .