A “sight-speed” human-computer interaction for augmented geospatial data acquisition and processing systems

Many real-time tasks in geospatial data analysis are based on matching of visual data, i.e. finding similarity and/or disparity in geoimages either in the remotely sensed source data or in geospatial vector and raster products. When human eyes scrutinize a scene, the brain performs matching of visual streams, acquired by eyes and transmitted via all chains of human visual system. As the result the brain creates a comfortable visual model of the scene and alarms, in case some distinct disparity in visual perception is found. While observing a scene, the optical axes of both eyes are naturally directed to the same area of the object, which is particularly true for visual perception of stereoscopic images on a computer screen. If eye movements are recorded while observing the virtual stereoscopic model generated in the brain, it is possible to detect such regions of interest using fixations, identified in eye-tracking protocols. These fixations can be considered as coordinates of feature points of an object being observed (regions of interest) and can be used to reconstruct corresponding 3D geometric models by applying classical stereo photogrammetric procedures. This novel way of utilizing eye-tracking leads to establishment of “eye-grammetry” - a new approach which melds human visual abilities and the computational power of modern computers to provide “sight-speed” interaction between the human operator and the computer software in augmented geospatial data acquisition and processing systems. This paper reviews theoretical and practical aspects of eye-tracking for real-time visual data processing and outlines two particular fields of applications where the proposed technology could be useful: gaze-tracking based 3D modeling and geospatial knowledge elicitation.