Stereo Imagery

Stereo imagery in remote sensingRemote SensingRemote sensing is the science of collecting data about Earth's surface without direct physical contact, primarily usi... comprises two or more images of the same ground area acquired from different viewpoints or angles, enabling the extraction of three-dimensional information through parallax measurement. Just as human binocular vision perceives depth from the slightly different views of each eye, stereo image pairs allow photogrammetric software to calculate the elevation and 3D position of every visible surface point. Acquisition methodsSatellite stereo pairs are collected using along-track stereo (forward and backward-looking sensors on the same platform, such as ASTER and ALOS PRISM) or cross-track stereo (images from adjacent orbits). High-resolution commercial satellites like WorldView and Pléiades can acquire multi-angle stereo triplets in a single pass. Aerial and drone stereo imagery is collected through overlapping flight lines with 60-80% forward overlap. ApplicationsStereo imagery is used to generate digital surface models (DSMs) and digital terrain models (DTMs), create 3D city models, measure building heights, produce topographic maps, and support 3D visualization for defense and planning applications. It provides elevation data in areas where LiDARLiDARLight Detection and Ranging (LiDAR) is a remote sensing technology that measures distances using laser pulses to crea... coverage is unavailable. Stereo imagery bridges the gap between 2D mapping and full 3D terrain modeling, providing a cost-effective method for deriving elevation information from optical sensors across any area covered by overlapping image acquisitions.