Bladeworks

Bladeworks renders portable Final Cut Pro XML projects (.fcpxml files and .fcpxmld bundles) to video.

Install

python -m pip install bladeworks

Bladeworks requires both ffmpeg and ffprobe on PATH to inspect source media and stream Studio preview audio. Run the prerequisite check after installation:

bladeworks doctor

Quick start

No project of your own yet? Render a packaged sample end to end:

bladeworks doctor                      # verify ffmpeg, ffprobe, and the torch device
bladeworks examples ls                 # list the packaged sample projects
bladeworks examples cp single_clip .   # copy single_clip.fcpxmld into the current directory
bladeworks render single_clip.fcpxmld --output out.mp4

Render your own project the same way:

bladeworks render path/to/project.fcpxmld --output output.mp4

Preview & edit locally

Both open one .fcpxmld bundle on 127.0.0.1, using the same render engine:

bladeworks studio path/to/project.fcpxmld   # interactive web editor (opens in a browser)
bladeworks server run path/to/project.fcpxmld   # headless HTTP API, no UI

Use studio to tweak and preview a bundle by hand; use server to drive the renderer programmatically (bladeworks server health --url <url> checks readiness).

More commands

bladeworks inspect path/to/project.fcpxml    # classify what a document uses, without rendering
bladeworks projects path/to/project.fcpxml   # list the projects a file/bundle contains
bladeworks proxy path/to/project.fcpxmld     # generate downscaled proxy media
bladeworks --help                            # all commands and options

Capabilities

Bladeworks treats real Final Cut Pro as its correctness oracle. Our fidelity goal differs by area:

• Core mechanics: spine & lanes, transform, crop, distort, conform, retiming, and compound clips. We aim for near-100% parity with Final Cut Pro, up to numeric differences in rendering arithmetic.
• Effects & transitions: we aim to cover every default-included Final Cut effect and transition template, at semantic parity, so the mechanism, timing, and endpoints match, while fine texture may differ.
• Color: we aim for 100% of Final Cut's color-adjustment functionality at strong approximate visual similarity, so a viewer shouldn't be able to tell the difference.

Where each capability stands today (✅ supported · 🟡 partial · ⛔ out of scope near-term):

Under the hood

We love tensors. As it turns out, PyTorch is a highly capable tensor-operation package that is now portable across a range of GPU-accelerated platforms such as NVIDIA graphics, Apple Silicon, and AMD. So we implemented the entire rendering system in the Python ecosystem, on PyTorch: every pixel operation is a tensor op, and the same code runs on whatever accelerator (or CPU) you have.

Core dependencies: PyTorch (rendering), PyAV (media decode / audio / mux), NumPy, Pillow, and fonttools; the local server and Studio add FastAPI, Uvicorn, and aiortc.

Contributing

At this time, while in early development, we are not accepting external source-code contributions. We do gladly welcome detailed bug reports and feature requests in the Issues section. Using your coding agent to give detailed feedback against the source will greatly increase the speed and likelihood of your request being incorporated.

Test a checkout

python -m pip install -r requirements.txt
python -m pip install -e . --no-deps
python -m pytest -q

License

Bladeworks is licensed under the GNU Affero General Public License v3.0 only. See LICENSE.