The ASTM E57 file format for 3D imaging data exchange

There is currently no general-purpose, open standard for storing data produced by three dimensional (3D) imaging systems, such as laser scanners. As a result, producers and consumers of such data rely on proprietary or ad-hoc formats to store and exchange data. There is a critical need in the 3D imaging industry for open standards that promote data interoperability among 3D imaging hardware and software systems. For the past three years, a group of volunteers has been working within the ASTM E57 Committee on 3D Imaging Systems to develop an open standard for 3D imaging system data exchange to meet this need. The E57 File Format for 3D Imaging Data Exchange (E57 format hereafter) is capable of storing point cloud data from laser scanners and other 3D imaging systems, as well as associated 2D imagery and core meta-data. This paper describes the motivation, requirements, design, and implementation of the E57 format, and highlights the technical concepts developed for the standard. We also compare the format with other proprietary or special purpose 3D imaging formats, such as the LAS format, and we discuss the open source library implementation designed to read, write, and validate E57 files.