Title
Compact bag-of-words visual representation for effective linear classification
Abstract
Bag-of-words approaches have been shown to achieve state-of-the-art performance in large-scale multimedia event detection. However, the commonly used histogram representation of bag-of-words requires large codebook sizes and expensive nonlinear kernel based classifiers for optimal performance. To address these two issues, we present a two-part generative model for compact visual representation, based on the i-vector approach recently proposed for speech and audio modeling. First, we use a Gaussian mixture model (GMM) to model the joint distribution of local descriptors. Second, we use a low-dimensional factor representation that constrains the GMM parameters to a subspace that preserves most of the information. We further extend this method to incorporate overlapping spatial regions, forming a highly compact visual representation that achieves superior performance with fast linear classifiers. We evaluate the method on a large video dataset used in the TRECVID 2011 MED evaluation. With linear classifiers, the proposed representation, with one-tenth of the storage footprint, outperforms soft quantization histograms used in the top performing TRECVID 2011 MED systems.
Year
DOI
Venue
2013
10.1145/2502081.2502138
ACM Multimedia 2001
Keywords
Field
DocType
effective linear classification,two-part generative model,gmm parameter,gaussian mixture model,state-of-the-art performance,compact visual representation,compact bag-of-words,low-dimensional factor representation,histogram representation,optimal performance,superior performance,proposed representation,linear classifier,bag of words,generative model
Bag-of-words model,Kernel (linear algebra),Computer vision,Histogram,Pattern recognition,Computer science,TRECVID,Artificial intelligence,Linear classifier,Mixture model,Generative model,Codebook
Conference
Citations 
PageRank 
References 
1
0.38
11
Authors
3
Name
Order
Citations
PageRank
Xiaodan Zhuang143324.71
Shuang Wu21717.23
Pradeep Natarajan3142.14