Extensible 3D compressed binary encoding MIME Type

Learn what model/x3d+binary identifies, how Extensible 3D compressed binary encoding files are encoded, and how Poly supports them.

MIME type details for model/x3d+binary

In active use
MIME typemodel/x3d+binary
Extensions
.x3db
First standardizedUnknown
Created byWeb3D Consortium and ISO/IEC
Browser support
Example applicationsXj3D, InstantReality
Poly supportStorage Only. Poly recognizes this media type but does not currently import binary X3D for 3D previews.
Indexed by PolyYes. Poly indexes filenames and basic file metadata.
Preview in PolyNo. Binary X3D is recognized but is not currently imported for Poly previews.
Poly agentNo. Poly does not currently provide binary X3D scene content to the agent.

What does model/x3d+binary mean?

X3DB is X3D's compressed binary encoding. Web3D describes conversion from a canonical X3D representation into a compressed binary stream and defines .x3db with model/x3d+binary.1 It is a separate representation from XML X3D, so renaming the suffix does not convert the file.

The associated extensions are .x3db. The media type identifies the format family; it does not convert bytes or guarantee that a reader supports every entity.

Poly support

Poly recognizes this type as stored binary X3D and indexes filenames and basic file metadata. It does not currently import binary X3D for a 3D preview or agent interaction.

ConstructWhat to expect
Geometry and scene structureAvailable when import succeeds.
Materials and texturesDepends on source constructs and supported rendition features.
Lighting, cameras, and animationAvailable when present and supported.

The identifier is recognized, but binary X3D is not currently imported for Poly previews.

Opening and conversion

Use a format-aware application when preserving editability matters. Conversion to glTF or OBJ can improve interchange for 3D viewing, while CAD and BIM workflows should retain the original schema and exchange context.

Footnotes

  1. https://www.web3d.org/documents/specifications/19776-3/V3.3/Part03/concepts.html.
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