ASTM_E_2807_-_11.pdf

Designation:E280711Standard Specification for3D Imaging Data Exchange,Version 1.01This standard is issued under the fixed designation E2807;the number immediately following the designation indicates the year oforiginal adoption or,in the case of revision,the year of last revision.A number in parentheses indicates the year of last reapproval.Asuperscript epsilon()indicates an editorial change since the last revision or reapproval.1.Scope1.1 This specification describes a data file exchange formatfor three-dimensional(3D)imaging data,known as the ASTME57 3D file format,Version 1.0.The term“E57 file”will beused as shorthand for“ASTM E57 3D file format”hereafter.1.2 An E57 file is capable of storing 3D point data,such asthat produced by a 3D imaging system,attributes associatedwith 3D point data,such as color or intensity,and 2D imagery,such as digital photographs obtained by a 3D imaging system.Furthermore,the standard defines an extension mechanism toaddress future aspects of 3D imaging.1.3 This specification describes all data that will be stored inthe file.The file is a combination of binary and eXtensibleMarkup Language(XML)formats and is fully documented inthis specification.1.4 All quantities standardized in this specification areexpressed in terms of SI units.No other units of measurementare included in this standard.1.4.1 DiscussionPlanar angles are specified in radians,which are considered a supplementary SI unit.1.5 This standard does not purport to address all of thesafety concerns,if any,associated with its use.It is theresponsibility of the user of this standard to establish appro-priate safety and health practices and determine the applica-bility of regulatory limitations prior to use.1.6 This standard does not purport to address legalconcerns,if any,associated with its use.It is the responsibilityof the user of this standard to comply with appropriateregulatory limitations prior to use.2.Referenced Documents2.1 ASTM Standards:2E2544 Terminology for Three-Dimensional(3D)ImagingSystems2.2 IEEE Standard:3754-1985 IEEE Standard for Binary Floating-PointArithme-tic2.3 IETF Standard:4RFC 3720 Internet Small Computer Systems Interface(iSCSI)2.4 W3C Standard:5XML Schema Part 2:Datatypes Second Edition3.Terminology3.1 DefinitionsTerminology used in this specification con-forms to the definitions included in Terminology E2544.3.2 Definitions of Terms Specific to This Standard:3.2.1 backward compatibility,nability of a file reader tounderstand a file created by a writer of an older version of a fileformat standard.3.2.2 byte,ngrouping of 8 bits,also known as an octet.3.2.3 camel case,nnaming convention in which com-pound words are joined without spaces with each words initialletter capitalized within the component and the first letter iseither upper or lowercase.3.2.4 camera image,nregular,rectangular grid of valuesthat stores data from a 2D imaging system,such as a camera.3.2.5 camera projection model,nmathematical formulaused to convert between 3D coordinates and pixels in a cameraimage.3.2.6 file offset,nsee physical file offset.3.2.7 file-level coordinate system,ncoordinate systemcommon to all 2D and 3D data sets in a given E57 file.3.2.8 forward compatibility,nability of a file reader toread a file that conforms to a newer version of a formatspecification than it was designed to read,specifically havingthe capability to understand those aspects of the file that weredefined in the version it was designed to read,while ignoringthose portions that were defined in later versions of the formatspecification.1This specification is under the jurisdiction of ASTM Committee E57 on 3DImaging Systems and is the direct responsibility of Subcommittee E57.04 on DataInteroperability.Current edition approved Feb.1,2011.Published March 2011.2For referenced ASTM standards,visit the ASTM website,www.astm.org,orcontact ASTM Customer Service at serviceastm.org.For Annual Book of ASTMStandards volume information,refer to the standards Document Summary page onthe ASTM website.3For referenced IEEE standards,visit http:/grouper.ieee.org/groups/754.4For referenced Internet Engineering Task Force(IETF)standards,visit theIETF website,www.ietf.org.5String representations(the lexical space)of the numeric datatypes are docu-mented in the W3C standard:“XML Schema Part 2:Datatypes Second Edition”,available on the website http:/www.w3.org/TR/xmlschema-2/.Copyright ASTM International,100 Barr Harbor Drive,PO Box C700,West Conshohocken,PA 19428-2959.United States1 3.2.9 logical length,nnumber of bytes used to describesome entity in an E57 file,not including CRC checksum bytes.3.2.10 physical file offset,nnumber of bytes preceding thespecified byte location in an E57 file,counting payload bytesand checksums.3.2.10.1 DiscussionThis term is also known as the fileoffset.3.2.11 physical length,nnumber of bytes used to describesome entity in an E57 file,including CRC checksum bytes.3.2.12 record,nsingle collection in a sequence ofidentically-t