Design of tuneable anti-aliasing filters for multiview displays
Atanas Boev, Robert Bregović, Atanas P. Gotchev · Proceedings of SPIE, the International Society for Optical Engineering/Proceedings of SPIE · 2011
Multiview displays suffer from two common artifacts - Moiré, caused by aliasing, and ghosting artifacts caused by crosstalk. By measuring the angular brightness function of each TFT element we create so-called brightness mask, which allows us to simulate the display output for a given input image. We consider multiview display as image processing channel and model the artifacts as distortions of the input signal. We test the channel by using a set of signals with various frequency components as input, and analyzing the output in the frequency domain. We derive the so-called bandpass region of the display, where the distortions introduced to the input signals are under certain threshold. Then, we extend the simulations including input signals with varying disparity, and obtain multiple passbands - one for each disparity level. We approximate each passband with a rectangle and store the height and width of that rectangle in a table. We propose an artifact mitigation framework which can be used for realtime processing of textures with known apparent depth. The framework gives the user ability to set so-called "3D-shapness" - a parameter, which controls the trade-off between visibility of details and presence of artifacts. The "3D-sharpness parameter determines what level of distortions is allowed in the final image, regardless of its disparity. The framework uses the approximated width and height of the passband areas in order to design an optimal (for the needed disparity and desired distortion level) anti-aliasing filter. We discuss a methodology for filter design, and show example results, based on measurements of an 8-view display.