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Gazihan Alankus gazihan@cse.wustl.edu. Vision-Realistic Rendering: Simulation of the Scanned Foveal Image from Wavefront Data of Human Subjects, Brian A. Barsky, 2004. Introduction. A new concept: vision-realistic rendering Rendering scenes as someone really sees them
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Gazihan Alankus gazihan@cse.wustl.edu Vision-Realistic Rendering: Simulation of the Scanned Foveal Image from Wavefront Data of Human Subjects, Brian A. Barsky, 2004
Introduction • A new concept: vision-realistic rendering • Rendering scenes as someone really sees them • Simulating the optical properties of the eye to get the retinal image • Applications • Creating more realistic renderings • Educating eye doctors and patients
Ideal Way • Trace rays from every photoreceptor in retina • Not feasible with current technology • Approximation using wavefront aberromery • A technology used for laser surgeries such as LASIK • Measures only one point in retina with a laser beam
Wavefront Aberrometry • 1mm laser beam is sent to the fovea using the half-silvered mirror • Fovea acts as a point light source and sends light out of the eye • The light is focused on the sensor using a lenslet array
Wavefront Aberrometry Actual Image
Object Space Point Spread Function • The vectors computed using the displacements of spots are converted to a surface using Zernkie polynomials • A continuous blurring function in object space is necessary • A discrete approximated version is used for a number of depth levels (Depth point spread functions) • Each surface normal is traced and counters in grids of given depth levels are incremented, and normalized at the end
Rendering • In order to see the whole image, people scan the image by moving their eyes • All the image is rendered using the simulation for the fovea • Looks realistic since people will move their eyes to see the whole image
Rendering • For each chosen depth, an image is rendered • Each depth image is convolved with its corresponding grid (DPSF) • A composite image is created using alpha blending from far to near
Results Patient with keratoconus
Conclusion • The image on the fovea is simulated to have a much better perceptually realistic image • How patients with certain eye conditions see is made available for education and better treatment • Whole image is rendered using the same distortion • If we have the technology to get information about more than one spot on retina, eye tracking can be used to show different renderings at different eye directions