Fable created novel 4D splat format
Points and comments are a snapshot, not live.
New .splat4d format compresses 4D gaussian splat sequences 16-58x using H.265-style GOPs and error-bounded quantization.
The .splat4d format stores dynamic gaussian splat scenes as a single streamable file. It splits static and dynamic splats (background stored once), uses deadband "hold" tracks to avoid quantization flicker, and H.265-style closed GOPs with keyframes and integer deltas for independent seeking. Entropy coding uses Morton ordering, zigzag deltas, byte-plane shuffle, and zstd. A 2-second demo scene (427 MB raw) compresses to 7.4 MB. Benchmarks across eight sequences show 16-58x compression vs raw, 14-20x vs per-frame gzip. Default error bounds: ±2mm position, ±4/255 color, exact rotation, ±2% scale. Designed for HTTP Range requests against object stores. Rust and JavaScript decoders produce bit-identical values. Code under MIT license.
What commenters are saying
Some commenters found the demo didn't work on their browsers (iOS Safari, Chrome without WebGPU flags), though others reported success. Several questioned the "novel" claim, noting all techniques are well-established in other codecs. The author clarified this is a specific application of H.265-like compression to 4D gaussian splats. One commenter pointed to their own related project (4splat) which is lossless. A brief subthread debated whether calling animated splats "4D" is justified, with consensus being that time earns the label since you can seek through it. Overall sentiment was positive about the engineering, with skepticism about originality.