Fable has created a streamable 4D Gaussian splat format that achieves up to 58x compression over raw data while maintaining exact error bounds. The format uses a static/dynamic split where unchanging background splats are stored once, while dynamic elements use H.265-style GOP encoding with keyframes and delta frames. This enables 640 MB/s encoding speeds and HTTP Range-native streaming for web browsers.

The format achieves dramatic size reductions by classifying splats as static or dynamic based on user-defined bounds (e.g., ±2mm position tolerance). Static splats store base values once, while dynamic splats use deadband tracking to emit deltas only when values exceed the bound. 14–20x smaller than gzip, the approach guarantees pointwise accuracy rather than average compression, with each GOP chunk decoding independently for seamless seeking.

Designed for plain HTTP Range requests against object stores like S3 or GCS, the format requires no server logic or manifests. A small header carries bounds and chunk indexes, followed by a static section for initial rendering and GOP chunks for playback. The Rust and JavaScript decoders reconstruct bit-identical values using integer math, avoiding temporal drift.

Benchmarks across CMU Panoptic and Neu3D datasets show the format shrinks 427MB raw sequences to 7.4MB files while supporting 60fps playback at 336k splats. The viewer renders directly in browsers with WebGPU (Chrome 113+, Safari 26+, Firefox 141+), making dynamic 3D scenes accessible without plugins or specialized hardware.