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Multifocal Projection: A Multiprojector Technique for Increasing Focal Depth
July/August 2006 (vol. 12 no. 4)
pp. 658-667

Abstract—In this paper, we describe a novel multifocal projection concept that applies conventional video projectors and camera feedback. Multiple projectors with differently adjusted focal planes, but overlapping image areas are used. They can be either differently positioned in the environment or can be integrated into a single projection unit. The defocus created on an arbitrary surface is estimated automatically for each projector pixel. If this is known, a final image with minimal defocus can be composed in real-time from individual pixel contributions of all projectors. Our technique is independent of the surfaces' geometry, color and texture, the environment light, as well as of the projectors' position, orientation, luminance, and chrominance.

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Index Terms:
Computing methodologies, computer graphics, picture/image generation, digitizing and scanning, display algorithms, image processing and computer vision, digitization and image capture, radiometry, reflectance, sampling, scanning, enhancement, sharpening and deblurring, scene analysis, color, shape.
Oliver Bimber, Andreas Emmerling, "Multifocal Projection: A Multiprojector Technique for Increasing Focal Depth," IEEE Transactions on Visualization and Computer Graphics, vol. 12, no. 4, pp. 658-667, July-Aug. 2006, doi:10.1109/TVCG.2006.75
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