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Learning Specific-Class Segmentation from Diverse Data. M. Pawan Kuma r, Haitherm Turki , Dan Preston and Daphne Koller at ICCV 2011. VGG reading group, 29 Nov 2011, presented by Varun Gulshan. Semantic image segmentation. Main idea.
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Learning Specific-Class Segmentation from Diverse Data M. Pawan Kumar, HaithermTurki, Dan Preston and Daphne Koller at ICCV 2011 VGG reading group, 29 Nov 2011, presented by VarunGulshan
Main idea • High level: Getting fully labelled data for training is expensive, use other easily available ‘diverse’ data for learning (bounding boxes, classification labels for image). Tags: Car, people Person bounding box
Implementing the idea • The bounding box/image classification data is incomplete for segmentation, fill in the missing information using latent variables. • Setup the training cost function using latent variables. Use their self-paced learning algorithm for Latent-SVM’s [NIPS2010] to optimise the training cost function. • While inferring latent variables, make sure latent variable estimation is consistent with the weak annotation. Setting up the inference problems to ensure this condition.
Energy function without latent variables Notation: Joint feature vector (essentially the terms of a CRF) Image Parameters to be trained
Structured output training Ground truth labels Loss function
Introducing latent variables But we don’t know what hk is (its latent), so maximise it out.
Self-paced optimisation Indicator variable to switch off the harder cases.
Second idea: Latent variable estimation The algorithm involves estimating annotation consistent latent variables in the following equation: More precisely
Move to white-board Me Beware of Equations You