Method for Increasing Apparent Amplitude Resolution, and Correcting Luminance Nonuniformity in Projected Displays
نویسنده
چکیده
Projectors suffer from nonuniformity across the display, as well as spurious contours due to insufficient levels. This work offers an efficient and accurate solution to both problems. A camera-based calibration scheme both measures the spatial luminance nonuniformity and detects the projected levels that are unique. Using this data, an attenuation array is built using reverse-3D-table lookup. The method provides an accurate correction without needing to know or measure the camera-toprojector response (gamma). Knowing the unique levels that the projector can display, the system can work with the actual reduced number of levels. Spurious contouring or banding distortion is corrected by a mean-preserving multilevel spatial dither system.
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