(registered 2026-10-27, last updated 2026-10-27)

Media type name: model

Media subtype name: vnd.pygrassreal.py3s

Required parameters: N/A

Optional parameters: N/A

Encoding considerations: binary

Binary container format using little-endian byte ordering with fixed 128-byte header.

Security considerations: The .py3s media type defines a binary asset container containing 3D Gaussian Splatting point data, 1:1 solid collision mesh geometry, and JSON-based spatial metadata. It does not contain active or executable code, scripts, or macros. Parsers should validate header magic ("PY3S"), version bounds, and payload offsets to prevent buffer overruns or out-of-bounds memory access.

Interoperability considerations: Designed for cross-platform 3D and Spatial Computing engines including Web (Three.js/WebGL/WebGPU), Unreal Engine 5, Unity, and Python machine learning pipelines. Standardized with little-endian byte ordering.

Published specification: https://github.com/PYGRASSREAL/pygrassreal-py3s-format/blob/main/SPECIFICATION.md

Applications which use this media: PyGrassReal AI spatial engines, Web 3D splat viewers, Unreal Engine 5 via PyGrassReal plugins, and 3D generative AI pipelines.

Fragment identifier considerations: N/A

Restrictions on usage: None

Additional information:

1. Deprecated alias names for this type: N/A
2. Magic number(s): ASCII "PY3S" (hex: 0x50 0x59 0x33 0x53) at byte offset 0
3. File extension(s): py3s
4. Macintosh file type code: N/A
5. Object Identifiers: N/A

General Comments: Standardized and maintained by PyGrassReal AI (https://pygrassreal.ai).

Person to contact for further information:

1. Name: Prachaya Buapad
2. Email: admin&pygrassreal.ai

Intended usage: COMMON

Intended for common exchange of 3D Gaussian Splats with native 1:1 physics collision in Spatial Computing and gaming ecosystems.

Author/Change controller: PyGrassReal AI (Prachaya Buapad), Founder & Chief Systems Architect. Contact: admin&pygrassreal.ai, Website: https://pygrassreal.ai