OpenCut

OpenCut is an experimental desktop video tool written in Rust with GPUI. The rust workspace contains shared libraries under rust/libs and these applications under rust/apps:

• editor: a non-destructive, folder-based multi-track editor.
• player: a standalone player for a video, audio, or timeline file.
• cli: a headless tool for probing, validating, and exporting timelines; see its README.

The project is an active prototype rather than a production-ready editor.

Devlog: https://www.youtube.com/playlist?list=PLRz1nfZl0jMU

Requirements

• Latest stable Rust (edition 2024)
• Existing FFmpeg development libraries in rust/vendor/ffmpeg-8.1.2/; do not build FFmpeg locally
• On macOS: Xcode command line tools and pkg-config (brew install pkg-config)

Build and run

Run commands from rust. Each command selects a platform explicitly:

cargo editor-mac                 # Windows: cargo editor-win
cargo player-mac -- <file>       # Windows: cargo player-win -- <file>
cargo build-editor-mac
cargo build-player-mac
cargo test-mac                   # Windows: cargo test-win

Extra Cargo flags such as --release are forwarded; application arguments follow --. These are native host commands, not cross-compilation commands. Editor aliases load .cargo/macos.toml or .cargo/windows.toml; player aliases use the FFmpeg-only .cargo/cli.toml or .cargo/ffmpeg-windows.toml. Small shell runners set the runtime library paths for the vendored FFmpeg.

For other Cargo operations, pass the platform configuration:

cargo check --config .cargo/macos.toml -p editor   # Windows: .cargo/windows.toml

Editor

• Open any folder as a project. Supported media appears in a live file tree without an import step; filter it, preview media in place, or drag media onto compatible tracks.
• Timelines are JSON files named *.timeline or *.timeline.json anywhere in the project. New Timeline creates a .timeline file; click it in the Explorer to open it.
• A new timeline has no tracks. Video tracks accept video and still images; audio tracks accept audio files.
• Select clips by clicking, Command-clicking, or drawing a selection rectangle. Move, duplicate, copy, cut, paste, and delete work on multiple clips, keep their relative timing, and are single undo steps.
• The selection tool moves clips within and between compatible tracks; the blade tool splits clips at the playhead. Invalid moves show feedback.
• Drag either edge of a video, audio, image, or text clip to change its duration. Trimming respects neighboring clips, source limits, and a one-frame minimum; each drag is one undo step and saves on release.
• Tracks can be created, deleted, reordered, hidden, muted, and locked.
• Select and drag subtitles directly in the preview. With Snap on, text aligns to canvas centers and edges with visible guides. Right-click a text clip and choose Apply style to track to copy its font, size, color, and position to other text clips on the same track, preserving their words and timing.
• The frame-based timeline supports horizontal zoom (including trackpad pinch), scrolling, frame ticks at high zoom, and optional snapping to the playhead and clip edges. Click the ruler to move the playhead. Playhead, scroll, zoom, and snapping are saved per timeline.
• The timeline preview plays composited video, including clip position and scale, with mixed audio that respects track and clip mute and clip gain. It plays a snapshot of the timeline; edits made after it opens are not yet reflected, except for frame rate changes and live text properties.
• Waveforms are generated in the background and kept in memory.
• Generate SRT on an audio or video file opens a transcription window. Press Start to transcribe; the window shows stages and offers Cancel.
• The top-right Export button opens a separate window for exporting a snapshot of the active timeline to MP4. It shows progress and provides Stop export; the window cannot close while exporting.
• To remove pauses based on subtitles, use the CLI's timeline keep-text-sections command. It removes time without text clips across all tracks and closes gaps; choose a new output file or --write-inplace.

Supported file extensions:

• Video: .mp4, .mov, .m4v, .mkv, .webm, .avi
• Images: .png, .jpg, .jpeg (added as five-second still clips)
• Audio: .aac, .flac, .m4a, .mp3, .ogg, .wav

Shortcut	Action
Space	Play or pause the preview
Left / Right	Move the playhead one frame
V / B	Selection / blade tool
Command-click	Add or remove a clip from the selection
Command-A	Select all clips on unlocked tracks
]	Select clips intersecting the mouse position and all clips to its right on unlocked tracks (pointer over timeline)
Command-B	Split the selected clips at the playhead
Backspace / Delete	Delete the selected clips
Command-D	Duplicate the selected clips
Command-C / Command-X / Command-V	Copy / cut / paste clips
Command-Z / Command-Shift-Z	Undo / redo
F / Esc	Enter / exit fullscreen preview
Option-Command-I	Toggle the GPUI inspector
Option-Command-R	Reveal the selected entry in Finder
Control-Shift-Enter	Open the selected entry in its default app

Player

The player opens the file given after --: a video, an audio file, or a *.timeline / *.timeline.json file. Press Space to play or pause, and click the seek bar to jump.

Project data

Each timeline is saved automatically as its own JSON file with its settings, media metadata, tracks, clips, and view state. Media paths are relative to the directory containing the timeline file. For example, timelines/edit.timeline.json references media/clip.mp4 as ../media/clip.mp4. Move or back up timelines and media together while preserving their relative locations. Absolute media paths are also supported. Source media is never rewritten, and waveforms are not written to the project.

The last opened project is stored in ~/.opencut/editor-settings.json. On startup the editor restores the active timeline and its playhead.

Development

cargo test-mac # Windows: cargo test-win
cargo check --config .cargo/macos.toml --all-targets --all-features
cargo clippy --config .cargo/macos.toml --all-features
cargo loc

cargo loc reports the project's Rust line count. Use .cargo/windows.toml on Windows. Plain cargo test loads no platform configuration; use test-mac or test-win for the editor and its native media dependencies.