Format

Wavefront OBJ File

Summary

Name: Wavefront OBJ File
Identifiers: PUID: fmt/1210
Format type: Model
Description: OBJ is an ASCII format for representing 3D geometry. The OBJ format supports both polygonal objects and free-form objects. Polygonal geometry uses points, lines, and faces to define objects while free-form geometry uses curves and surfaces.
File extensions: obj
Submitted by: Archaeology Data Service / Archaeology Data Service

Description: BOF:0-1024 (can be unlimited preamble, but we want to anchor near the beginning of the file for most cases). Must have vertices: v <space> 3 x space separated floating point values that can have a negative value or not representing x, y, z. w is optional, line ending. Later, the vertices must have a face: f <space> 3+ integer values, can be negative, separated by space. Faces count from 1. PRONOM uses this minimally viable set, however each face can have values for ‘vertex textures’ and ‘vertex normals’ - if present, these values are separated by /. Each row ends in new line character
Provenance: Based extensively on http://paulbourke.net/dataformats/obj/ 08/2023- Modified BOF signature to increase two of the byte ranges. Submitted by Preservica.

Min Frag Length: Absolute from BOF
Offset: 0
Max offset: 1024
Byte Sequence: 7620{0-8}[30:39]2E[30:39]{0-32}20{0-8}[30:39]2E[30:39]{0-32}20{0-8}[30:39]2E[30:39]{0-64}0A*6620{0-1}[31:39]{0-20}20{0-1}[31:39]{0-20}20{0-1}[31:39]{0-40}0A
Endianness: None