Title
Local Naive Bayes Nearest Neighbor for image classification
Abstract
We present Local Naive Bayes Nearest Neighbor, an improvement to the NBNN image classification algorithm that increases classification accuracy and improves its ability to scale to large numbers of object classes. The key observation is that only the classes represented in the local neighborhood of a descriptor contribute significantly and reliably to their posterior probability estimates. Instead of maintaining a separate search structure for each class's training descriptors, we merge all of the reference data together into one search structure, allowing quick identification of a descriptor's local neighborhood. We show an increase in classification accuracy when we ignore adjustments to the more distant classes and show that the run time grows with the log of the number of classes rather than linearly in the number of classes as did the original. Local NBNN gives a 100 times speed-up over the original NBNN on the Caltech 256 dataset. We also provide the first head-to-head comparison of NBNN against spatial pyramid methods using a common set of input features. We show that local NBNN outperforms all previous NBNN based methods and the original spatial pyramid model. However, we find that local NBNN, while competitive with, does not beat state-of-the-art spatial pyramid methods that use local soft assignment and max-pooling.
Year
DOI
Venue
2011
10.1109/CVPR.2012.6248111
Computer Vision and Pattern Recognition
Keywords
Field
DocType
Bayes methods,image classification,maximum likelihood estimation,NBNN image classification algorithm,class training descriptors,local naive Bayes nearest neighbor,local soft assignment,max-pooling,posterior probability estimation,search structure,spatial pyramid methods
Reference data (financial markets),Kernel (linear algebra),Approximation algorithm,Pattern recognition,Computer science,Posterior probability,Naive bayes nearest neighbor,Pyramid,Artificial intelligence,Merge (version control),Contextual image classification,Machine learning
Journal
Volume
Issue
ISSN
abs/1112.0059
1
1063-6919 E-ISBN : 978-1-4673-1227-1
ISBN
Citations 
PageRank 
978-1-4673-1227-1
69
1.79
References 
Authors
12
2
Name
Order
Citations
PageRank
Sancho McCann12007.28
D. G. Lowe2157181413.60