Development of 3D image measurement system and stereo‐matching method, and its archaeological measurement

Three-dimensional measurement and modeling systems with digital cameras on PCs are now making progress and increasingly felt to be desirable in terrestrial (close-range) photogrammetry for such sectors as cultural heritage preservation, architecture, civil engineering, manufacturing, measurement, etc. Therefore, we have developed a system to improve the accuracy of stereo-matching, which is the very core of 3D measurement. As a stereo-matching method, in order to minimize mismatch and to be robust in geometric distortions, occlusion, as well as brightness change, we invented the Coarse-to-Fine Strategy Method by integrating OCM (orientation code matching) with LSM (least squares matching). This system could attain an accuracy of 0.26 mm in experiments on a mannequin. In real-world experiments on archaeological ruins in Greece and Turkey, the accuracy was within 1 cm, compared with their blueprint plan. Formerly, workers required at least 1.5 months for this kind of survey operation with existing methods, but now only 3 or 4 days is needed. This confirmed the practicality and efficiency of the new method. Herein we demonstrate our new system of 3D measurement and stereo-matching and present some concrete examples of its practical application. © 2013 Wiley Periodicals, Inc. Electron Comm Jpn, 96(6): 9–21, 2013; Published online in Wiley Online Library (wileyonlinelibrary.com). DOI 10.1002/ecj.11459