Watermarking 3D scenes past the 77-bit ceiling that CLIP's token limit imposed
AspireAI community · arXiv
Embedding ownership and provenance data in 3D Gaussian Splatting assets needs more capacity than current methods can carry. Bit-to-token watermarking schemes built on a pre-trained text encoder top out at 77 bits, because CLIP's fixed 77-token context length will not accept tokens beyond that, and positional embeddings do not extend. BitC-3DGS encodes multiple message bits per token instead, compressing several bits into one semantic token, with a dual-branch architecture that jointly decompresses chunks and decodes bits and a hard-message sampling strategy to improve combinatorial coverage during decoder training. On the Blender and LLFF datasets the method reaches 128-bit capacity with recovery accuracy comparable to recent 64-bit state of the art, alongside rendering fidelity. It matters for anyone shipping 3D assets through a pipeline where provenance has to survive the asset format.
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