Omniverse Gaussian Splat Converter

A pip-installable Python package for converting 3D Gaussian Splat data (PLY and SPZ formats) to USD using the ParticleField3DGaussianSplat schema.

Installation

pip install gsplat2USD

For USD support (if not already installed):

pip install gsplat2USD[usd]

Building From Source

The converter package lives in source/python and builds with standard Python packaging tools.

Use Python 3.11 or 3.12. Python 3.10 is not compatible with the pinned numpy==2.3.1 dependency.

cd source/python
python -m pip install --upgrade pip build
python -m build

The build writes both source and wheel distributions to dist/:

dist/gsplat2usd-<version>.tar.gz
dist/gsplat2usd-<version>-py3-none-any.whl

Replace <version> with the package version generated by your build.

To install and smoke test the local source tree:

python -m venv .venv
source .venv/bin/activate  # Windows PowerShell: .\.venv\Scripts\Activate.ps1
python -m pip install ".[usd]"
python -m gsplat2USD --help
python -m gsplat2USD -i input.ply -o output.usda

You can also test the built wheel directly:

python -m pip install "dist/gsplat2usd-<version>-py3-none-any.whl[usd]"
gsplat2USD -i input.ply -o output.usda

Usage

Command Line

# Convert a PLY file to USDZ
gsplat2USD -i input.ply -o output.usdz

# Convert an SPZ file to USDA with Z-up axis
gsplat2USD -i input.spz -o output.usda --up-axis Z

# Generate spherical harmonics and scales from raw PLY
gsplat2USD -i input.ply -o output.usdz --generateSh --generateScales

You can also run via python -m:

python -m gsplat2USD -i input.ply -o output.usdz

Python API

from gsplat2USD import read_ply, read_spz, write_gaussian_splat_usd

# Read a PLY file
splat_data = read_ply("scene.ply")

# Write to USD
write_gaussian_splat_usd(splat_data, "scene.usdz", source_file="scene.ply")

# Read an SPZ file
splat_data = read_spz("scene.spz")

# Write to USD with options
write_gaussian_splat_usd(
    splat_data,
    "scene.usda",
    source_file="scene.spz",
    up_axis="Z",
    rotation_degrees=(90.0, 0.0, 0.0),
)