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What do you do when you know that you don’t know?. Abhijit Bendale*, Terrance Boult Samsung Research America* University of Colorado of Colorado Springs. Facial Attributes.
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What do you do when you know that you don’t know? Abhijit Bendale*, Terrance Boult Samsung Research America* University of Colorado of Colorado Springs
Facial Attributes N Kumar, A Berg, P Belhumeur, S Nayar “Describable Visual Attributes for Face Verification and Image Search” IEEE TPAMI 2011 B Klare, S Klum, J Klontz, E Taborsky, T Akgul, A Jain “Suspect Identification Based on Descriptive Facial Attributes” IEEE/IAPR IJCB 2014
Facial Attributes Based Face Recognition Probe Face Recognition System Gallery Mugshots CCTV B Klare, S Klum, J Klontz, E Taborsky, T Akgul, A Jain “Suspect Identification Based on Descriptive Facial Attributes” IEEE/IAPR IJCB 2014
Unknowns in Real World N Kumar, A Berg, P Belhumeur, S Nayar “Describable Visual Attributes for Face Verification and Image Search” IEEE TPAMI 2011 M Wilber, E Rudd, B Heflin, Y Lui, T Boult “Exemplar codes for facial attributes and tattoo recognition” WACV 2014
Handling Missing Features Reduced Feature Models Model 1 Model 2 Model 3 Model 4 …. Model 5 Y. Ding and A. Ross. “A comparison of imputation methods for handling missing scores in biometric fusion”. Pattern Recognition, pages 919–933, 2012 G. Chechik, G. Heitz, G. Elidan, P. Abbeel, and D. Koller. “Max-margin classification of data with absent features”. J. of Machine Learning Research, pages 1–21, 2008.
Our Operational Scenario • Access to only stored model and operational data • No prior knowledge of nature of missing data • Storage limitation : Cannot store countless “reduced models” • Impractical for face recognition Operational Data / Support Vectors Stored Model Decision Score Test Data P(A) or P(B) Missing Data At Test Time
Support Vector Machines subject to Differentiate wrt w and b to get solution
Missing Data in Context of Linear SVMs and Imputation X1 = 0 Misclassification caused due to zero imputation X2 = 0
Run Time Bias Estimation New hyper plane obtained After optimizing the bias term • Project Operational Data • Optimize for Bias • Obtain optimal hyper plane in operational domain • Classify in the projected domain
Run Time Bias Estimation Refactored Projection Error Refactor Risk Optimal Bias : Minimize Refactor Risk
Experimental Setup USPS Dataset 0-9 Numbers, 9298 images, 7291 for training, 2007 for testing Each image represented as 256 dimensional vector Binary Classification : 1-vs-All MNIST Dataset 0-9 Numbers, 70000 images, 60000 for training, 10000 for testing Image size 28x28. Feature size 784 Binary Classification : 1-vs-All LFW Dataset Pair Matching 6000 images. 5400 Training, 600 Testing 10 fold validation Feature type: Attributes of faces. Feature vector size: 146 Binary Classification : Same pair, different Pair
Comparison with Other Methods [5] G. Chechik, G. Heitz, G. Elidan, P. Abbeel, and D. Koller. “Max-margin classification of data with absent features”. J. of Machine Learning Research, pages 1–21, 2008. [11] Z. Ghahramani and M. I. Jordan. “Supervised learning from incomplete data via an EM approach” NIPS 1994 [29] A. J. Smola, S. V. N. Vishwanathan, and T. Hofmann. Kernel methods for missing variables. In Proc. Wksp on Articial Intelligence and Statistics, 2005
Risk Estimation for Missing Data Meta-Recognition False Accept Rate Meta-Recognition Miss Detection Rate
Meta-Recognition Analysis for Missing Data Ideal Risk Estimator
Conclusion • Operational Adaptation for Biometrics Systems • Algorithm for Run Time Bias Estimation for SVMs as an effective way for handling missing features • Adaptation Risk Estimator for SVMs • Meta-Recognition Analysis for handling missing features
Future Work A Bendale, T Boult “Reliable Posterior Probability Estimation for Streaming Face Recognition” CVPR Biometrics Workshop 2014 A Bendale, T Boult “Towards Open World Recognition” CVPR 2015 A Bendale, T Boult “Towards Open Set Deep Networks” CVPR 2016 Tuesday – June 28 10:00 – 10:30 AM Short Oral 10:30 AM – 12:30 PM Poster Session
We are releasing code for this work along with libsvm wrappers…! I don’t trust you or your claims Awesome..!!