An Intelligent Model for Visual Scene Analysis and Compression
Amjad Rehman and Tanzila Saba
Faculty of Computer Science and Information Systems, University Teknologi Malaysia, Malaysia
Faculty of Computer Science and Information Systems, University Teknologi Malaysia, Malaysia
Abstract: This paper presents an improved approach for indicating visually salient regions of an image based upon a known visual search task. The proposed approach employs a robust model of instantaneous visual attention (i.e. “bottom-up”) combined with a pixel probability map derived from the automatic detection of a previously-seen object (task-dependent i.e. (“top-down”). The objects to be recognized are parameterized quickly in advance by a viewpoint-invariant spatial distribution of Speeded Up Robust Features (SURF) interest-points. The bottom-up and top-down object probability images are fused to produce a task-dependent saliency map. The proposed approach is validated using observer eye-tracker data collected under object search-and-count tasking. Proposed approach shows 13% higher overlap with true attention areas under task compared to bottom-up saliency alone. The new combined saliency map is further used to develop a new intelligent compression technique which is an extension of Discrete Cosine Transform (DCT) encoding. The proposed approach is demonstrated on surveillance-style footage throughout.
Keywords: Visualization, discrete cosine transform, image compression, scene analysis.
Received May 27, 2010; accepted January 3, 2011