Author :
Rosebrock, Adrian ; Oates, Tim ; Caban, Jesus
Abstract :
Constructing an image classification system using strong, local invariant descriptors is both time consuming and tedious, requiring many experimentations and parameter tunings to obtain an adequately performing model. Furthermore training a system in a given domain and then migrating the model to a separate domain will likely yield poor performance. As the recent Boston Marathon attacks demonstrated, large, unstructured image databases from traffic cameras, security systems, law enforcement officials, and citizens can be quickly amassed for authorities to review, however, reviewing each and every image is a expensive undertaking, in terms of both time and human intervention. Inherently, reviewing crime scene images is a classification task. For example, authorities may want to know if a given image contains a suspect, a suspicious package, or if there are injured people in the photo. Given an emergency situation, these classifications will be needed as quickly and accurately as possible. In this work we present a rapidly deployable image classification system using "feature-views", which each view consists of a set of weak, global features. These weak global descriptors are computationally simple to extract, intuitive to understand, and require substantially less parameter tuning than their local invariant counterparts. We demonstrate that by combining weak features with ensemble methods we are able to outperform current state-of-the-art methods or achieve comparable accuracy with much less effort and domain knowledge. Finally we provide both theoretical and empirical justification for our ensemble framework that can be used to construct rapidly deployable image classification systems called "Ecosembles".
Keywords :
Bayes methods; feature extraction; image classification; statistical distributions; visual databases; ecosembles; ensemble methods; feature extraction; feature-views; image classification system; image databases; parameter tuning; Accuracy; Birds; Feature extraction; Histograms; Probability distribution; Training; Vectors; ensemble methods; feature extraction and selection; supervised learning;