Perceptual ability with real-world nighttime scenes: Image-intensified, infrared, and fused-color imagery

We investigated human perceptual performance allowed by relatively impoveri shed information conveyed in nighttime natural scenes. We used images of ni ght time outdoor scenes rendered in image-intensified low-light visible (i( 2)) sensors, thermal infrared (ir) sensors, and an i(2)/ir fusion technique with information added. We found that nighttime imagery provides adequate low-level image information for effective perceptual organization on a clas sification task, but that performance for exemplars within a given object c ategory is dependent on the image type. Overall performance was best with t he false-color fused images. This is consistent with the suggestion in the literature that color plays a predominate role in perceptual grouping and s egmenting of objects in a scene and supports the suggestion that the additi on of color in complex achromatic scenes aids the perceptual organization r equired for visual search. In the present study, we address the issue of as sessment of perceptual performance with alternative night-vision sensors an d fusion methods and begin to characterize perceptual organization abilitie s permitted by the information in relatively impoverished images of complex scenes. Applications of this research include improving night vision, medi cal, and other devices that use alternative sensors or degraded imagery.