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Single Exposure High Dynamic Range Imaging with a Conventional Camera Using Cross-Screen Filters

Masters Thesis, October 2009, University of British Columbia (Vancouver)

Without specialized sensor technology or custom, multi-chip cameras, high dynamic range imaging typically involves time-sequential capture of multiple photographs. The obvious downside to this approach is that it cannot easily be applied to images with moving objects, especially if the motions are complex.
We propose a novel technique that captures HDR images in a single exposure, using a conventional camera sensors and with minimal impact on the image quality. Our method spreads energy from bright regions into the neighboring unsaturated pixels using a cross-screen, or star filter. Bright pixels still get clipped, but information about the energy of these clipped pixels gets encoded in the form of superimposed glare in discrete directions. Such glare can be separated from the original image with the help of natural image priors, while the glare itself can then be used to reconstruct saturated pixels using 2D tomographic methods.
[pdf] [cIRcle link]

Realtime Soft Shadow Volume

Masters Thesis, August 2007, Bangladesh University of Engineering and Technology

[BUET Library page]

Incremental Convex Hull Algorithm for Admission Control

Undergraduate Thesis, June 2005, Bangladesh University of Engineering and Technology

Developed an incremental admission control heuristic. Admission control and resource allocation problem can be modelled as a Multidimension Multiple Choice Knapsack (MMKP) problem. The algorithm proposed in this thesis is based on a previous heuristic, Convex Hull Heuristic (CHEU). Since computing convex hull very expensive, it was shown that the incremental version works nearly as good as the regular counterpart, but requires a very small amount of computation for each request.

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