Image reconstruction of static scenes from a static event camera using an LCD projector

Event cameras are promising sensors that show many advantages over frame-based cameras. Unlike conventional cameras, whose pixels share a common exposure time, event-based cameras represent a novel bio-inspired technology capable of capturing scenes with a high dynamic range and without motion blur. Due to their working principle, an event is generated when a pixel's brightness changes. Therefore, no event data is generated in a scenario where there is no relative motion between the event camera and the scene. However, in this study, we present a new method to enable event generation with a static event camera on a scene with static objects, aiming to eliminate the requirement of relative motion between event camera and the scene. By projecting custom designed grayscale pattern sequences onto static scenes, we successfully triggered a controlled event generation without requiring camera or object motion. Instead of a direct black-to-white transition, we used a sequence of contrast compatible grayscale projection pattern to regulate event rates and prevent bandwidth overload. To prevent event loss over time, we equalized all timestamps to the first timestamp. Since events in event cameras gradually lose their impact and reset over time, this adjustment prevents the decay of event information and ensures a continuous and stable event generation. Despite the absence of motion, we achieved reasonable results in image quality metrics such as MSE, LPIPS, SSIM. In this way, we aim to expand the usage areas of event cameras and make significant progress in data collection processes, especially for static camera and scenes.