If you shoot long takes on action cams or phones, LosslessCut is the fastest way to carve out selects without re‑encoding. This article gives you a quick mental model, a copy‑paste workflow, and a keyboard‑first cheat sheet for macOS.
Why LosslessCut?
- Speed: “Normal (keyframe) cut” copies the exact video/audio packets—no transcode—so exports are instant.
- Quality: zero generational loss (no added compression).
- Focus: perfect for building selects folders before editing in DaVinci Resolve, Premiere, or Final Cut.
⚡️ Lossless rule of thumb: Put In/Out on keyframes and export with Normal (keyframe) cut. If you need frame‑accurate edges, use Smart cut (only tiny re‑encode around the cuts).
Quick Start (3 steps)
- Open a clip → jump to a keyframe (
⌥→/⌥←) → press I. - Move to the end keyframe → press O.
- Press + (Add segment). Repeat for more segments → press E (Export) → choose Normal / keyframe cut.
Set the output folder (e.g., 01_SELECTS/OSMO or 01_SELECTS/PHONE) once and reuse it.
Keyboard Cheat Sheet (macOS)
Mark & Segments
| Shortcut | Action |
|---|---|
| I | Set In |
| O | Set Out |
| + | Add segment (keeps I→O) |
| B | Split segment at playhead |
| ↵ Enter | Label segment |
| ⌫ Backspace | Remove cut/segment |
Export (Lossless)
| Shortcut | Action |
|---|---|
| E | Export dialog |
| Choose Normal (keyframe) cut for truly lossless; Smart cut only when you must cut off‑keyframe | |
| Options: Include segments (export only marked parts), Merge segments (single file) |
Seek & Playback
| Shortcut | Action |
|---|---|
| , / . | Step 1 frame back / forward |
| ⌥← / ⌥→ | Jump to prev/next keyframe (best for lossless cuts) |
| ← / → | Small seek |
| J / K / L | Play backward / pause / play forward (tap L to speed up) |
| Space | Play / pause |
| ⌘← / ⌘→ | Jump ~1% of clip duration |
Segment Navigation & Batch
| Shortcut | Action |
|---|---|
| ↑ / ↓ | Previous / next segment |
| ⇧⌥↑ / ⇧⌥↓ | Jump and seek to prev/next segment |
| ⇧↓ / ⇧↑ | Next / previous file |
| ⌃⇧↓ / ⌃⇧↑ | Open next / previous file |
Shortcut behavior can vary slightly by version; adjust in Settings if needed.
One‑Time Settings
- Default export mode: Normal / keyframe cut
- Output folder: a dedicated
01_SELECTS/…per device (e.g.,PHONE,OSMO) - Container: keep same as source unless you have a reason to change
- Time format: HMS (
00h00m05s) for readable segment names - Show keyframes: helpful to land cuts precisely
Filename Pattern (traceable)
Use source name + time ranges for instant provenance:
DJI_0123_00m10s-00m21s.mp4
iPhone_4567_02m05s-02m17s.mov
Resolve‑Friendly Mini‑Workflow
- Triage in Finder: tag Green (keeper), Red (reject), Blue (B‑roll). Avoid deleting originals yet.
- LosslessCut: carve selects on keyframes; export with Normal cut into
01_SELECTS/.... - Import to DaVinci Resolve: edit on your vertical 4K master timeline (e.g., 2160×3840 @ 25 fps).
- Deliver: archive ProRes 422 + PCM master; upload H.264 1080×1920 for socials.
Tip: For mixed frame rates (e.g., 50 fps action cam + 24 fps phone), a 25 fps timeline is a neat compromise (50→25 gives perfect 50% slow‑mo; 24→25 only needs a +4.17% speed change).
“Why is it re‑encoding?” (Troubleshooting)
- Cuts not on keyframes: switch to Smart cut or re‑mark on keyframes.
- Codec/container changed: keep the original container/streams when possible.
- Filters applied: LosslessCut is designed for copy operations—avoid processing filters.
- Rotation confusion: some phones store rotation in metadata. Use a rotation‑aware sort when organizing (ExifTool/ffprobe) or verify orientation in your NLE.
FAQ
Is “Smart cut” still lossless?
Mostly—the untouched parts remain bit‑for‑bit, but LosslessCut re‑encodes small ranges near the cut to achieve frame accuracy.
Can I join multiple selects into one file?
Yes—toggle Merge segments in the Export dialog.
Which formats are supported?
Anything ffmpeg can demux: MP4/MOV (H.264/HEVC), MPEG‑TS, MKV, etc. Stability varies by source—test with a short clip first.
How does this compare to doing trims in Resolve?
NLE trims re‑encode on export unless you enable smart‑render workflows. LosslessCut gives you instant, identical‑quality selects before you ever open your NLE.
Download a one‑page cheat sheet
If you prefer a condensed version for your notes app or to print, copy the “Keyboard Cheat Sheet” table above as Markdown, or export this page as PDF from your browser.
If this guide helped, feel free to link it—credit appreciated.