(registered 2023-01-24, last updated 2023-01-24)

Media type name: model

Media subtype name: JT

Required parameters: N/A

Optional parameters: N/A

Encoding considerations: binary

Security considerations: The JT file format utilizes compression and 
   encoding algorithms to produce compact representations of data. 
   The types of compression algorithms used vary from standard data 
   type agnostic LZMA dictionary compression to entropy coding 
   algorithms that exploit characteristics of the data types being 
   compressed. Implementation Coding algorithms for compression 
   techniques are included with the specification. Compressed storage 
   formats qualitatively vary from "lossless" to "lossy".

   A corrupted or maliciously created file might possibly be able to 
   crash a particular program that reads it in, and in the presence 
   of buffer-overrun or similar bugs it might be possible to exploit 
   these. However, short of crashing the program reading the file, 
   the format contains geometry descriptions, topological model data, 
   tessellation data and meta date with no executable or scripted 
   content and no features relating to disk or network access. As 
   such, there should be no way to use it to send viruses or similar 
   malicious code.

Interoperability considerations: The JT format is a scene graph with 
   facet information. CAD specific node data, lights, textures and 
   materials, Product and Manufacturing Information (PMI), Precise 
   Part definitions (as B-Rep) and Metadata are in scope for the 
   format.

Published specification: The JT specification is published as ISO 
   14306 and available from the ISO website for a nominal fee.

Applications which use this media: The JT format is available for 
   export, and in some cases import, from all major engineering CAD 
   applications including offerings from Siemens DISW, Dassault, PTC 
   and Autodesk. JT is also a data source for industry leading 
   visualization applications, gaming engines and marketing 
   collateral generation tools. Open source tools such as Open 
   Cascade also support JT.

Fragment identifier considerations: N/A

Restrictions on usage: N/A

Additional information:

   1. Deprecated alias names for this type: N/A
   2. Magic number(s): N/A
   3. File extension(s): .jt
   4. Macintosh file type code: N/A
   5. Object Identifiers: N/A

Person to contact for further information:

   1. Name: Michael Zink
   2. Email: mike.zink&siemens.com

Intended usage: COMMON

   JT is an industry focused, high-performance, lightweight, flexible 
   file format for capturing and repurposing 3D data that enables 
   collaboration, validation and visualization throughout a Model 
   Based Enterprise.

Author/Change controller: ISO/TC 184/SC 4 (https://www.iso.org/committee/54158.html)