A digital photogrammetric workstation on the WEB

Abstract The main features of a WEB-based tool for digital architectural photogrammetry called Architectural Photogrammetry Network Tool for Education and Research (ARPENTEUR) are presented. The aim of this project is to propose a photogrammetric software package made freely available on the Internet as an applet through a simple browser ( http://www.arpenteur.net ). All the photogrammetric adjustment and image processing classes are written in Java™. The use of large applets in photogrammetry has not been very advanced until now but rate transfers and compatibility levels of Internet browsers will increase in the near future. Users can set up their own projects by transferring their images, camera, and control information on the ARPENTEUR servers from any place in the world connected on the Internet. Various examples of small format architectural photogrammetry projects are also accessible via WWW and can be used for teaching. This software is an extension of the Traitement d'Images et Photogrammetrie Numerique (TIPHON) software developed at ENSAIS-LERGEC. The photogrammetric model is currently computed by the traditional steps of inner, relative and absolute orientations. The measurements in the images can be performed manually or by image correlation. The measured points, lines, and geometrical primitives are recorded in text files and visualised inside a standard WEB browser. The plotting module is especially dedicated to architectural surveys and based on a formalisation of architectural and geometrical knowledge. The latest developments of the Java programming language and object-oriented systems are used in ARPENTEUR, both in the photogrammetric and in the architectural part, and ensure a high level of compatibility with any hardware platform supporting a WEB browser.