stereophotogrammetrya

Stereophotogrammetry is a technique within photogrammetry that uses stereo image pairs to recover three-dimensional measurements of scenes or objects. By analyzing the parallax between two images taken from slightly different viewpoints, it yields a 3D representation from two-dimensional pictures.

Fundamental to the method are camera calibration and accurate knowledge of the relative positions of the cameras (interior and exterior orientation). With rectified stereo images or proper epipolar geometry, corresponding points can be matched along horizontal lines, and their disparities converted into depth information through triangulation.

Typical workflow: capture overlapping stereo pairs (or more generally multi-view images), perform camera calibration, estimate orientation, perform stereo matching or multi-view stereo to obtain a dense point cloud, reconstruct surfaces, and apply texture mapping. Finally, perform quality control and export standard formats for GIS or modeling software.

Equipment and software: specialized stereo rigs or two synchronized cameras, tripods or mounts, and robust photogrammetry software such as Agisoft Metashape, RealityCapture, Pix4D, or open-source toolchains like OpenMVG/OpenMVS. The method yields dense 3D geometry and color information from the imaged surfaces.

Applications: architectural surveying, cultural heritage documentation, archaeology, forensics, industrial metrology, geology and paleontology, urban planning, and film or game asset creation.

Accuracy and limitations: results depend on baseline, focal length, image resolution, overlap, and scene texture. Close-range stereo photogrammetry can reach millimeter to centimeter accuracy; aerial or drone-based stereo photogrammetry typically provides decimeter to meter-scale accuracy, depending on altitude and ground sampling distance. Challenges include occlusions, textureless materials, shiny or reflective surfaces, and variable lighting.

Terminology: the standard term is stereophotogrammetry. The form stereophotogrammetrya is not used in established literature and may be a typographical error.